for the modern Australian business.
Let's face it, we know that growing and sustaining a business is one of the hardest things you've ever done.
There's never enough hours in the day, money or resources.
After helping over 2,000 growing small businesses over the past 4 years, we quickly realised that legal advice and protection ends up at the bottom of your pile, until it's too late.
Most people would prefer to go to the dentist than see a lawyer.
We're changing that for you!
Progressive Legal provides an amazing, cost effective service for entrepreneurs, at a time when they need it most. Too often entrepreneurs and small business owners are going without legal advice, or opting for below par, template based services. The Progressive Legal team are highly competent, dedicated to supporting their clients, fabulous to deal with and - most importantly - I know my business is safe in their hands.
I have utilised Ian's legal services right from the beginning of my ventures. Ian provides exceptional legal counsel and responds quickly and sharply to eliminate legal issues which arise and potential legal issues in the future. I highly recommend Ian to anyone seeking not just a legal expert, but someone who goes that extra step further to ensure that you and your business are legally compliant.
Getting the contract today, working through it and seeing how solid it was, was amazing. I'm very happy with your service. I can see that you have really seen a lack in how startups and independent business are taken care of, and provided an excellent and very heartfelt solution.
Fabulous customer service, responding promptly to my queries and ensuring I understood everything clearly.
Great service, awesome working with the team on a quick turnaround – that was exactly what I needed before launch.
Thank you so much to Progressive Legal and Legal Shield. Our business is going through some contractual issues and unfortunately we were very much working without proper legal cover. Legal Shield has provided Emirias with the support, documentation and advice that we very much needed to underpin and sustain our growth.
Progressive Legal has designed a fantastic program for Entrepreneurs and SME's. A no non-sense, straight forward approach, and very affordable!
I'm all about following the rules, and as a new business owner, I was a bit sketchy on what those rules and limitations were. Thankfully I found Progressive Legal, they know ALL the rules and help me follow them to a 'T'. I can now confidently go into the marketplace with a Client Services Agreement that I know is right for both me and my clients.
One of the most switched on Small Businessman I have ever had the pleasure of spending time with. He has been an asset to my business and going forward I know his help and advice will be invaluable.
Ian is very detail oriented who quickly and proficiently provided detailed legal advice regarding contracts, confidentiality agreements, trademarking, government grants and all round great counsel. In summary, I have never met such an incredibly precise lawyer who is also personable and become a friend to Cherrii, my social network, and to me.
Ian is like an unknown treasure to those who don't know him and pearl to those who do. It's important to have a good lawyer on your team when you start up to avoid falling into ditches you can't see (and aren't expected to see). I recommend any entrepreneur get in touch with Ian, especially also now that he helps entrepreneurs get SMB grants!
Whether it be company structure set up, intellectual property protection, commercial disputes or general commercial legal advice – I have no hesitation in recommending Ian as a great legal advisor for small business owners.
Ian and his team helped me sort out a trademark for a sub-brand of my core business in an efficient, uncomplicated fashion. As someone with a relatively young business and limited budget, I found their service and advice to be truly awesome – especially the fixed price for their element of the cost. Highly recommend Ian to anyone looking for legal counsel that keeps it simple and gets done what has to be done!
Ian is my go to person for anything legal!. I'm an entrepreneur and my time is precious! It's comforting knowing Ian has knowledge on everything legal for startu ups & it's great to know he will give real advice and affordable rates. He's very business minded and savvy - so I know I have all areas covered! Cannot thank him enough for the help received so far! Will be recommending to all my entrepreneur network.
Carla's advice was clear and practical, very thorough understanding of all the applicable legislation and was able to very quickly understand our situation and recommend a course of action. Gave me a lot of confidence. Highly recommend you contact her!
With my speaking, my book, my workshops, meetups, blog and personal brand all tied into my "Design You®" processes and terminology, I wanted to make sure I got it right. The team at Progressive Legal have been invaluable as I negotiated the legal quagmire of trademarking my brand; what's more – they made it easy for me and fun. I wasn't expecting that!
We're pretty darn lucky to work with some amazing clients throughout Australia, and the always inspiring Grace Lever is no exception! Over the past 12 months, we've loved working alongside Grace to get all her legal elements in order for her business.
Check out what she has to say in this video!


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Gig Review: Mac DeMarco
Canadian Indie Artist Mac Demarco played the O2 Academy in Birmingham this week.
On Wednesday 27th November, Canadian indie artist Mac DeMarco, graced the O2 Academy with an incredible display of music and artistry. Armed with his fourth album, DeMarco pleased the crowd with fan favourites, older album tracks and some rock 'n' roll covers, providing the perfect mix of slow and upbeat letting the crowd switch between gentle sways to boogying.
Mac launched the show with 'On the Level', not an obvious choice but it was clear the crowd were ready for his set as the opening chords played. Followed by the ever-popular 'Salad Days', it was clear that DeMarco was in his element.
Throughout the show, fans were treated to the perfect mix of chat and music, with the guitarist even offering up an anecdote of how Mac taught him to play. In between his own tracks, he led the band in fun instrumentals, returning to the music of 'Freaking Out the Neighbourhood' after the incredible crowd reaction. The funky riffs and sweet beats of these jams provided the perfect soundtrack to get dancing in the crowded academy.
Known for his quirkiness and on-stage antics, the show seemed much tamer compared to previous sets, he did not fail to entertain the crowd with his peculiar noises, quirky dance moves and camera zooming into their bums. His style of baggy jeans and a fisherman's hat, reassured fans he was still the same incredible artist they couldn't wait to see and his artistry throughout the set stood to this testament.
An audience made up of many students, Mac was in the perfect company for his tunes and fashion choices treating them to a double encore. Nearing the end of the set, DeMarco announced that they were nearing the end only to continue blasting hit covers in his own unique style. DeMarco's supporting act, Los Bitchos, decided to join the band and the man himself in the encore with an eccentric rendition of The Champs 'Tequila', which of course consisted of lots of tequila swigs and crowd roars. After saying goodbye, fans hadn't had enough and chanted him back on stage where no one was then left disappointed. DeMarco rocked out to a Metallica cover closing with a moshing crowd who clearly couldn't get enough.
An evening with DeMarco and his talented band ensures a night for an unforgettable musical performance and it will be over before you're ready to stop dancing. There is no doubt that Mac lives up to and beyond expectations.
Mac's latest album 'Here Comes The Cowboy' is out now. Stream it on Spotify:
Image by: Mona Maruyama
ICC Champions Trophy Preview
The BBC Good Food Show: Top Picks for Students
Never mind run out, England were washed out of Australia

redpajama_set_name: RedPajamaCommonCrawl


In the United States alone, about 4 million babies are born each year. The vast majority of babies grow to be happy and healthy. However, the number of birth injuries that take place in hospitals around the country remains alarmingly high.
Out of every 1,000 deliveries, 6 to 8 babies are born with a birth injury. That means there are roughly 30,000 birth injuries a year.
The consequences of a birth injury can be catastrophic to parents and children. Not only can a birth injury lead to permanent impairment, such as paralysis or disfigurement, but it can also lead to neonatal death.
Victims around the country have filed medical malpractice lawsuits against healthcare personnel or institutions to receive the compensation they deserve. Find out more about birth injuries and how a birth injury lawyer can help.
Sometimes called birth trauma, a birth injury is a physical injury suffered during the birthing process. The injury can occur before, during, or after the birth itself.
Birth defects are often described separately from birth injuries. A birth defect is a problem that develops while the fetus is still in the womb. This can be something genetic like a heart murmur, Down syndrome, and sickle-cell anemia or something else like the age of the parents.
Birth injuries are sometimes defined more broadly by the legal community as an injury a baby suffers that was preventable. This could be preventable injuries caused while the mother is still pregnant. For example, a pregnant woman might be accidentally prescribed unsafe medication or a doctor may fail to notice or treat gestational diabetes. Both of these could lead to injuries, defects, or premature birth.
Depending on the type of birth injury, symptoms may manifest themselves in different ways. Some birth injuries are not noticeable while at the hospital. It may take years for some children to develop symptoms.
In either case, it is important to identify any birth injuries as soon as possible. Some birth injuries can increase in severity if left untreated. Symptoms are sometimes broken down by type. There are action symptoms, health symptoms, and physical symptoms. When many of these symptoms are observed together, it could indicate a problem.
The types of birth injuries vary greatly. These are among the most common types of birth injuries.
Some children may suffer from facial paralysis that results in the loss of muscle movement in the face. The most frequent cause is from a difficult delivery. The use of forceps during delivery is also a risk factor. Facial nerves can be temporarily or permanently damaged.
This is when there is bleeding beneath the cranial bones. According to Stanford Children's Health, it can appear as a raised lump in the baby's head several hours after birth.4 It will usually disappear on its own but will sometimes require a blood transfusion.
Fractures are also common birth injuries. The collarbone is most susceptible to fracture during breech deliveries as the baby may be in an awkward position. The legs, arms, and skull also have the potential to fracture.
Caput Succedaneum describes swelling under the scalp of a baby shortly after birth. The condition usually resolves itself in a few days but can increase the likelihood of developing jaundice.
A birth injury can change lives forever, but the injuries suffered by babies are often preventable. When that's the case, a parent may be able to file a lawsuit against a doctor or institution for medical malpractice.
A qualified attorney will be able to tell you whether you were the victim of negligence from a medical professional. Examples can include improper use of forceps or vacuum, failing to conduct specialized tests, failing to monitor the mother or baby, delaying the order of a C-section, and more.
Birth injury lawsuits can be long and complex, which is why it's important to walk through the process with a lawyer.
When a baby suffers a birth injury that affects their life and everyone around them, the family may be eligible to receive monetary compensation from the negligent party. Damages cannot turn back time, but they can go toward covering medical expenses, lost wages, pain and suffering, and more.
Along with monetary compensation, filing a lawsuit helps prevent similar injuries from happening again by holding those who were negligent accountable.
Contact a birth injury attorney today to find out how to get the compensation you deserve and help stop preventable injuries.
Nirupama Laroia, MBBS, MD. "Birth Trauma", Medscape, https://emedicine.medscape.com/article/980112-overview#a1. Accessed April 17th, 2018.
What to Expect. "BABY & TODDLER MILESTONES", What to Expect, https://www.whattoexpect.com/milestones/. Accessed April 17th, 2018.
UCP. "Fact Sheet", United Cerebral Palsy, https://ucp.org/wp-content/uploads/2013/02/cp-fact-sheet.pdf. Accessed April 17th, 2018.
Stanford Children's Health. "Birth Injury", Stanford Children's Health, http://www.stanfordchildrens.org/en/topic/default?id=birth-injury-90-P02340. Accessed April 17th, 2018.


Although it is not made clear in MFC documentation and such, the typical way to subclass a control is by simply using the ClassWizard to generate the code to subclass the control. Many of us are not aware that the code ClassWizard generates for "Control" category variables does this.
I will use an edit control as an example but the following applies to all common controls. For an edit control you have at least two categories to choose from. If you choose "Value" for "Category" then the member variable type can be a "CString" and the control is not subclassed for it. If you choose "Control" for "Category" then the member variable type can be "CEdit" and the control is subclassed using the object created with that class. If you create a class derived from CEdit then your derived class gets added to the list of classes that a "Control" category member variable can use for member variables. If you create a "Control Category" member variable using your derived class as the Variable type then ClassWizard generates code that subclasses the edit control using your derived class.


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Home > Learning > Departments > School of People, Environment and Planning > Collaborations
BackSchool of People, Environment and Planning
School of People, Environment and Planning
The School of People, Environment and Planning collaborates with external organisations on research activities of mutual benefit.
Living Lab grew out of three fruitful partnerships with local government, developed through the university's Challenging Sustainability project. It proved that innovative solutions emerge when designers and social scientists get together with city planners and community members to look at complicated issues afresh.
Visit Living Lab website
Devnet (Development Studies Network of Aotearoa New Zealand) organises a national conference every two years to bring together academics, students, development practitioners and policy makers. Its website provides links to international development research conducted in New Zealand.
Regina Scheyvens from the School of People, Environment and Planning is the current chair of the DevNet Steering Committee.
Visit DevNet website
EUCN
EUCN (New Zealand European Union Centres Network) is a network of New Zealand's universities that aims to combine research, teaching and outreach on the impact, role and understanding of the European Union within New Zealand and the Pacific region. It is multidisciplinary and involves economics, politics, security, innovation, development, democratic values and people and cultures.
Jeff McNeill is Massey University's representative on the EUCN Board.
Visit EUCN website
NZADDs
NZADDs (New Zealand Aid and Development Dialogues) works to promote dialogue and critical thinking about New Zealand's role in international development. Its website contains press releases and working papers relating to changes in the New Zealand aid programme, as well as links to international websites reporting on effective aid delivery.
Visit NZADDs website
NZIRI
The New Zealand India Research Institute (NZIRI) is the national centre for India Studies in New Zealand. It comprises a consortium of scholars based at New Zealand universities focused on research in and on India.
Visit NZIRI website
Page authorised by Head of School
Last updated on Wednesday 17 April 2019


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Wilhelmsdorf er en kommune i den mittelfrankiske Landkreis Neustadt an der Aisch-Bad Windsheim i den tyske delstat Bayern. Den er hjemsted for Verwaltungsgemeinschaft Hagenbüchach-Wilhelmsdorf. Wilhelmsdorf må ikke forveksles med Wilhermsdorf i Landkreis Fürth, der ligger 15 km væk.

Geografi
Nabokommuner er Emskirchen og Oberreichenbach.

Inddeling
Ud over Wilhelmsdorf, ligger i kommunen landsbyerne:
 Ebersbach
 Oberalbach
 Stadelhof
 Trabelshof
 Unteralbachermühle

Historie
Wilhelmsdorf blev grundlagt af Hugenoterne, og indtil begyndelsen af det 20. århundrede var den protestantiske landsbykirke fransk præget.

Wilhelmsdorf var i det 19. århundrede kendt for strømpefabrikation; Omkring år 1900 grundlagde købmanden Edmund Boden og teknikeren Johann Christian Lotter en fabrik for passere og tegneredskaber som i det 20. århundrede gav Wilhelmsdorf en betydningsfuld rolle. I byens Zirkelmuseum fortælles mere om historien.

Eksterne henvisninger

 Zirkelmuseum des Heimatvereins "Eintracht"

redpajama_set_name: RedPajamaWikipedia


In our fourth episode of this series Bethan asks Dr. Antonis Kousoulis the BIG questions about mental health, the whats, the whys and how we can prevent mental ill health.
In this podcast we discuss the benefits of sleep and green space on your mental health. Guest Julie Dunn, a Research Scientist from the University of Liverpool features on the show and talks about how mental health and wellbeing inspired her 'Sleep Well' garden.
Ben Bidwell (The Naked Professors) on how learning to love himself on the inside made him proud of the person he saw in the mirror.
How can we improve the mental health of students? Our panel discuss.


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Aircraft Systems for Pilots
by Dale De Remer
1,045 pages10 hours
This book is a single source, concise presentation of what pilots should know about basic aircraft systems. The content reflects the author's more than thirty-five years experience of flying and fourteen years of teaching Aircraft Systems to university students.
Aircraft Systems for Pilots includes a brief study of the fundamentals of physical matter (from which airplanes are made) and mechanics (how airplane parts act and react). The author provides sufficient study of each type of system to allow the professional pilot to stay abreast of the critical learning which must occur as the pilot advances into management of more complex aircraft.
Subject covered include physics, aircraft engine types and construction, reciprocating engine theory of operation, engine lubrication and cooling, propellers and governors, fuels and fuel systems, power management, supercharging and turbocharging, pressurization and high altitude operations, electrical principles, electrical components, aircraft electrical systems, hydraulic systems and landing gear, pneumatic and deicing systems, aircraft structures and flight controls, weight and balance, inspections, pilot maintenance, and aircraft instrument systems. Illustrated throughout, study questions conclude each chapter and includes index.
In print for more than 30 years and continually updated through the years, this 4th Edition continues to serve as the comprehensive college textbook for pilots learning aircraft systems.
Publisher: Aviation Supplies & Academics, Inc.Released: May 25, 2018ISBN: 9781619546288Format: book
A Pilot's Guide to Aircraft and Their Systems
Author Dale Crane
Flying IFR: The Practical Information You Need to Fly Actual IFR Flights
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An Aviator's Field Guide to Middle-Altitude Flying: Practical skills and tips for flying between 10,000 and 25,000 feet MSL
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The Advanced Pilot's Flight Manual
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The Pilot's Manual: Instrument Flying: All the aeronautical knowledge required to pass the FAA exams, IFR checkride, and operate as an Instrument-Rated pilot
Author The Pilot's Manual Editorial Board
Tips to Fly By: Thousands of PIC hours' worth of tips and tricks of the trade
Mental Math for Pilots: A Study Guide
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Airline Pilot Technical Interviews: A Study Guide
Aerodynamics for Aviators
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Flying the Weather Map
Managing Risk: Best Practices for Pilots
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The Pilot's Manual: Multi-Engine Flying: All the aeronautical knowledge required to earn a multi-engine rating on your pilot certificate
The Complete Multi-Engine Pilot
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Airline Transport Pilot Oral Exam Guide: The comprehensive guide to prepare you for the FAA checkride
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Air Carrier Operations
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Guide to the Flight Review For Pilots & Instructors: Complete preparation for issuing or taking a flight review including both the ground and flight requirements
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The Flight Instructor's Survival Guide: true, witty, insightful stories illustrating the fundamentals of instructing
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The Pilot's Manual: Access to Flight: Integrated Private and Instrument Curriculum
Aviation Weather: FAA Advisory Circular (AC) 00-6B
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Pilots in Command: Your Best Trip, Every Trip
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The Student Pilot's Flight Manual: From First Flight to Pilot Certificate
737 Performance Reference Handbook - EASA Edition
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Severe Weather Flying: Increase your knowledge and skill to avoid thunderstorms, icing and severe weather
Author Dennis Newton
Train Like You Fly: A Flight Instructor's Guide to Scenario-based Training
Confident Flying: A Pilot Upgrade: A guide to better risk management, decision making and judgement, to get the most out of your flying.
Flying The Big Jets (4th Edition)
Author Stanley Stewart
The Pilot's Guide to The Airline Cockpit
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Lesson Plans to Train Like You Fly: A flight instructor's reference for scenario-based training
Checklist for Success: A Pilot's Guide to the Successful Airline Interview
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Col. John "Skip" Rawson on Princeton Flying School Podcast 5: aviator, businessman, flying in Cubs at the age of 14, later flew B 47's and Constellations in the Air Force, charter pilot, member of the Tora! Tora! Confederate Air Force flight demonstration team flying Japanese Zero replicas
Author Princeton Flying School Podcast
043 USAF Maj Gen Carl Schneider: Interview with Major General Carl Schneider, USAF (Retired) and author of "Jet Pioneer: A Fighter Pilot's Memoir." www.jetpioneer.com THANKS to our sponsors! Nashville Flight Training Bose A20 Aviation Headset T-shirts & other...
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Prepping For Spring: With Spring fast approaching, and I know most of us are ready to be done with this Winter stuff, we discuss some things you might want to do to get your fleet ready for the upcoming flying season! In this 247th episode, we also discuss the...
Author TheCrashCast
044 High School Aviation: Talking with my buddy Derek Rowe who is an Aviation teacher in a local high school. That's right - Aviation as a high school subject! We discuss what Derek's students are learning about aviation, how they are earning college credits towards an...
APG 175 – Solar Impulse 2 Reaches Hawaii, United Down Due to Computer Glitch, Fool in a Balloon and Lawn Chair: Captain Jeff is joined by Miami Rick (@Miami_Rick) and Dr. Steph (@Plumdiggity). - Intro by Evan Schoo. - News in this episode: Bonanza B36 crashes in Massachusetts Air New Zealand B772 at Rarotonga blew over plane spotters
Author Airline Pilot Guy - Aviation Podcast
AviatorCast Episode 18: Hangar Talk w/ Rick Durden: The Pilots Lounge Author | Aviation Lawyer | The Thinking Pilot's Flight Manual Author | FAAST Team: What does over 7000 hours in 200 types of airplanes get you? Rick Durden, highly experienced aviator, author and aviation lawyer, talking airplanes!
Author AviatorCast: Flight Training & Aviation Podcast
025 My Discovery Flight: I'm always encouraging potential pilots to go take a discovery flight, so this episode I tell the story of how I got interested in flying and my discovery flight, which was my first time in a small airplane. T-shirts & other merchandise...
Plane Talking UK Podcast Episode 183: Plane Talking UK Podcast Episode 183 Aviation News Radio Show featuring A320 Podcast
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005 Social Side of Being a Pilot: The surprisingly social aspects of being a pilot. Clubs, chapters, flying to breakfast, etc. Keywords: Aviation, General Aviation, Plane, Planes, Airplane, Airplanes, Fly, Flying, Flight, Pilot, Pilots
Safety at 40,000 Feet: This week, endoscopies for jet engines, how the aviation industry could have us cruising for an infectious bruising, the workings of radar, and whether cheap flights actually cost the Earth. Plus, in the news, why doctors could soon be culturing your...
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Are Windowless Airplanes the Future of Flight?
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Airspeed - Aircraft Icing and the Researchers of the Icing Branch at NASA Glenn Research Center: It's the season for icing here in the midwest. As some instrument-rated and other pilots can tell you, few things have higher pucker factor than looking out at your wings while you're in the clouds and seeing ice begin to form. Most general aviation...
Author Airspeed
RFT 267: Airline Pilot Beth Powell: Beth Powell was recently featured in Essence magazine as one of the few female African-American airline pilots operating in the United States. Beth's interest in flying began when she was 15 years old and took an introductory airplane flight in her...
Author Ready For Takeoff - Turn Your Aviation Passion Into A Career
062 Allyssa VanMeter: Interview with Allyssa VanMeter, a fairly new pilot and airplane owner. Allyssa has a ton of passion for flying, and has already had some great experiences including flying her newly purchased plane to Oshkosh and flying in Alaska. THANKS...
RFT 001: Getting An Airline Job: We give you an overview of the series and walk you through the process of becoming an airline pilot. Ready For Takeoff - Aviation and Commercial Airline Podcast - Your source for thoughts from the flight deck and beyond for Airplane Geeks looking for...
Episode 4. Avionics Technology Today compared to Legacy Aircraft.: In this Episode, we discuss innovative Avionic Technologies from the maintainer point of iew. Ou Guest, Chapper Mike is an expert in the industry and has supported the Commercial, Corprate and Military industries regarding engineering,...
Author The Hangardeck Podcast
RFT 095: Career Counselor Karen Kahn: Karen Kahn has been actively involved in the aviation industry for 30+ years. She is one of the nation's first female commercial pilots hired and one of few pioneers still working. Prior to starting her airline career in 1977, she instructed at the...
ACP095 What is Ab Initio Flight Training?: We recently received a number of listener questions asking "what is Ab Initio flight training?" Ab Initio is normally used by carriers outside the United States, but with the current shortage of qualified pilots some airlines are considering their own...
Author Aviation Careers Podcast
Go / No Go Part Deux, December 13, 2015: SimpleFlight Radio - Defining Your Aviation Lifestyle
Author SimpleFlight Radio
75 Mental Health and Stress in Pilots, Seattle Stolen Plane, Blackfly and Sun Flyer 2 Electric Aircraft: 75 Max talks about depression among pilots, two recent pilot suicide accidents, and two incidents in which stress from the death of a friend or family member caused accidents.
Author Aviation News Talk podcast
001 Intro: First episode and introduction to the new Why We Fly podcast and host, Mike Harris. Keywords: Aviation, General Aviation, Plane, Planes, Airplane, Airplanes, Fly, Flying, Flight, Pilot, Pilots
041 Total Eclipse by Airplane: My buddy Brett Leslie put an airplane to good use to go see the total solar eclipse. Hear his total eclipse story as well as some other highlights from his experiences as a pilot & Flight Instructor. THANKS to our sponsors! Nashville Flight...
026 Announcements & What You Can Do with a Pilot's License: Several announcements of developments with the podcast as we start our second year. Also a discussion of some of the things you can do with a pilot's license that in my experience are surprising to people who are not (yet) pilots. ...
RFT 063: AOPA Senior Vice President Katie Pribyl: Katie leads AOPA's Communications division and is responsible for its You Can Fly programs. Under the You Can Fly umbrella, Katie and her team are building programs designed to get lapsed pilots back in the air, provide more affordable access to...
006 First Flights: 006 First Flights 9:14 A flight path over dowtown Nashville that I've taken a couple of friends on for their first flight. Keywords: Aviation, General Aviation, Plane, Planes, Airplane, Airplanes, Fly, Flying, Flight, Pilot, Pilots
APG 208.5 – Feedback Extra!: The crew for this week's episode: Captain Jeff, Dr. Steph, and Captain Nick. Airline Pilot Guy App - Android Airline Pilot Guy App - iPhone/iPad 32R Aviation Apparel Promo code APG gets you 10 percent off! FEEDBACK -
How does an upside down airplane's engine get fuel?: Airplanes rely on gravity to disperse fuel to the engine, but what happens when the plane is flying upside down? Tune in to this podcast from HowStuffWorks.com to discover ways that acrobatic planes fly upside down without crashing.
PJP 026 | Meticulous Aircraft Appearance Care w/ Jim Mathiasch of Jet Clean 360: In this episode, we're on site in sunny Scottsdale, AZ to cover a common question: "How important is aircraft appearance to private jet owners and operators?" Jim Mathiasch of Jet Clean 360 talks today about how vital aircraft appearance is to protecti...
Author Private Jet Podcast
004 My Son's First Flight: The story of taking my son on his first flight when he was 2 1/2 weeks old. Keywords: Aviation, General Aviation, Plane, Planes, Airplane, Airplanes, Fly, Flying, Flight, Pilot, Pilots
Are robots taking over pilots' jobs?: Self flying planes are coming - Are you ready to fly without a human pilot?
Author Komando On Demand
Where the 737 Max Went Off Course
Changes to Boeing's training regimen may have left pilots unprepared to handle the jet's flawed controls
Aero Magazine International
Eight Trends In Private Aviation
A sentence of Heraclitus has defined its work: "Nobody enters twice in the same river, since, when this occurs, the person is not the same, as well as the waters are already other ones". The same may be said about business aviation. It is a market wi
Where Airplanes Go to Die—and Be Reborn
An excavator crunches up the airframe of a Boeing 727-200. Jet Yard A typical plane flies for 25 years or so before it starts to wear out. When a plane is finally grounded, though, it doesn't have to be the end of the line. Storing retired airplanes
Living The High Life
Private jets are no longer the preserve of rock stars and billionaire businessman, as T3 found when flying to the Isle of Islay with Stratajet (stratajet.com), a platform focused on making private jet travel more affordable. After arriving at a small
Buyer Guide 's 2018
For making a safe decision, the aircraft buyer uses to get involved in a wide and complex choice process, including studies and analyses that can reduce the risks of such a necessary and heavy investment. A mistaken choice would make the acquisition
Text by JARED PAUL STERN Bell & Ross watches have a distinct visceral appeal: Wearing one makes you feel like a fighter pilot. Founded in Paris in 1992 and inspired by aircraft instrumentation, the brand has defied the conventions of centuries of wat
The FAA Rigorously Tested the Boeing 737's Software
Two Boeing 737 Max 8 airplanes have crashed under similar circumstances in the past six months, one in October in Indonesia and the other in Ethiopia last week. These were new planes, and both had a control system installed that has been implicated i
Myanmar Military Plane Carrying More Than 100 People Goes Missing
The plane reportedly lost contact about 30 minutes after it took off from the coastal town of Myeik, bound for Yangon. No trace of the aircraft or its passengers has been found so far.
A One-of-a-kind Electric Racing Plane Just Debuted In Dubai
The White Lightning's engineers say the acceleration of its motors will outperform that of traditional combustion engines.
Getting On A Plane? Here's How They're Inspected To Keep You Safe
Southwest planes The April 14 incident aboard Southwest flight 1380 was the first death aboard a U.S.-based airliner in nearly a decade. Stan Horaczek Aviation has had a great run in recent years. Until the fatal Southwest Airlines accident on April
From Cockpit To Controller: Former Pilot Finds A New Way To Fly
When former helicopter pilot Tony Zimlich retired from a 20-year military career, he worried about his civilian job prospects. Then he discovered the burgeoning world of commercial drone work.
ENGINE DESIGNATION: D8-600 CYLINDERS: In-line six INDUCTION: four-stroke, direct-injected, turbocharged diesel engine with aftercooler BORE/STROKE: 110/135 mm (4.33/5.31 in.) DISPLACEMENT: 7.7 liters (469.7 cu. in.) COMPRESSION RATIO: 16.5:1 DRY WEIG
WITH NEARLY 2 million lines of code and a host of futuristic technologies, the F-35 Joint Strike Fighter isn't the kind of product one designs with only a pencil and paper. But Bob Ruszkowski, a longtime aircraft engineer for Lockheed Martin and its
Electric Aircraft Could Soon Become An Industry Standard
Siemens Magnus featured a clear cowling for a look under the hood. Rob Mark This story was originally published by Flying Magazine. As part of Siemens Innovation Day held recently in Chicago—created, in part, to highlight the company's progress to da
After Boeing Crashes, More People Want Help Taming Fear Of Flying
If you're scared of flying, the news of two recent airline crashes might have you in jitters. Instructors who help people overcome that fear say enrollments have doubled since the incidents.
Apple Magazine
Airbus Is Ready For Pilotless Jets
The chief salesman for Airbus says his company already has the technology to fly passenger planes without pilots at all — and is working on winning over regulators and travelers to the idea. Christian Scherer also said in an interview with Media this
Fast Bikes
Project Leader Hiroyuki Watanabe
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General Characteristics of Matter
Physics is the term applied to that area of knowledge regarding the basic and fundamental nature of matter and energy. It does not attempt to determine why matter and energy behave as they do in their relation to physical phenomena, but rather how they behave.
The persons who fly, maintain, and repair aircraft should have a knowledge of basic physics in order to be able to understand the interactions of matter and energy.
This may be a review for those who have a background in physics. I suggest you read it anyway. You may find the aircraft applications interesting!
Although matter is the most basic of all things related to the field of physics and the material world, it is the hardest to define. Since it cannot be rigidly defined, this chapter will point out those characteristics which are easily recognizable.
Matter itself cannot be destroyed, but it can be changed from one state into another state by chemical or physical means. Matter is often considered in terms of the energy it contains, absorbs, or gives off. Under certain controlled conditions, it can be made to aid man in the process of flight.
Matter is any substance that occupies space and has mass. There are four states of matter: (1) Solids, (2) liquids, (3) gases, and (4) plasma. Solids have a definite volume and a definite shape; liquids have a definite volume, but they take the shape of the containing vessel; gases have neither a definite volume nor a definite shape. Gases not only take the shape of the containing vessel, but they expand and fill the vessel, no matter what its volume. Plasma is made up of very hot, ionized gases. The gases are so hot that thermal collisions dissociate all of the atoms into positive ions and electrons. Most of the matter in the universe is plasma. The sun and all the stars are giant balls of plasma. About 99% of the total mass of the universe is in this plasma state.
Water is a good example of matter changing from one state to another. At high temperature it is in the gaseous state known as steam. At moderate temperatures it is a liquid, and at low temperatures it becomes ice, a solid state. In this example, the temperature is the dominant factor in determining the state that the substance assumes. Pressure is another important factor that will effect changes in the state of matter. At pressures lower than atmospheric, water will boil and thus change into steam at temperatures lower than 212° F (100° C). For example, the vapor pressure of water at 98.6° F (37° C) is equal to atmospheric pressure at about 63,000 feet. This means that blood will boil at that pressure altitude! Pressure is a critical factor in changing some gases to liquids or solids. Normally, when pressure and chilling are both applied to a gas, it assumes a liquid state. Liquid air, which is a mixture of oxygen and nitrogen, is produced in this manner.
All matter has certain characteristics or general properties. These properties are defined elementally and broadly at this point, and more specifically in applications throughout the text. Among these properties and relationships are:
Volume—meaning to occupy space; having some measurements such as length, width, and height. It may be measured in cubic inches, cubic centimeters, liters, or the like.
Inertia is the characteristic of matter that resists change in motion (velocity and direction). Newton's first law is sometimes called the law of inertia: A body at rest will remain at rest and a body in motion will continue in motion with a constant speed along a straight-line path (constant velocity) unless acted upon by some net force .
Mass is a measure of the inertia of a body, and therefore is a measure of the quantity of matter associated with the body. Units for measuring mass are usually considered fundamental units for a measurement system. The gram and kilogram are units for measuring mass in the metric system of measurement, and the corresponding English unit for measuring mass is the less familiar unit called the slug.
Gravitation, sometimes called mass attraction, is a force that results from the characteristic of particles of matter that causes attraction or pull on other particles of matter. This mutual attraction of the mass of particles can be described in terms of gravitational forces with Newton's law of universal gravitation. Gravitational forces, like all other forces (pulls and pushes), are measured with the English unit of the pound or the metric unit of the Newton.
Weight is the name commonly used for the gravitational force of attraction between the Earth and a body (mass) near the Earth. Weight is a force and is described with force units such as the pound or Newton. Since the weight of a body (gravitational force acting on the mass of the body) is proportional to the mass of the body, these different physical quantities, weight and mass, are sometimes confused.
Density is a quantity which is useful when describing matter, especially when in the liquid or gaseous state. Depending upon the application, density can be defined as either weight density (weight per unit volume) or as mass density (mass per unit volume).
Figure 1-1. Comparison of metric and English systems of measurement.
Systems of Measurement
The two most commonly used systems of measurement are the English system, which is still in general use in the United States, and the metric system, used in most European countries and now adopted by the Armed Forces of the United States. The metric system is normally used in all scientific applications.
The metric system is sometimes called the cgs system because it uses as basic measuring units, the centimeter (c) to measure length, the gram (g) to measure mass, and the second (s) to measure time. The metric system is also referred to as the mks system (meter, kilogram, second).
The English system uses different units for the measurement of mass and length. The pound is the unit of weight; the foot and inch are used to measure length. The second is used to measure time as in the metric system.
The units of one system can be converted to units in the other system by using a conversion factor or by referring to a chart similar to that shown in figure 1-1. In this figure the English and the metric systems are compared; in addition, a column of equivalents is included which can be used to convert units from one system to the other.
Because both liquids and gases flow freely, they are called fluids, from the Latin word fluidus, meaning to flow. A fluid is defined as a substance that changes its shape easily and takes the shape of its container. This applies to both liquids and gases. The characteristics of liquids and gases may be grouped under similarities and differences.
Similar characteristics are as follows:
Each has no definite shape but conforms to the shape of the container.
Both readily transmit pressures.
Differential characteristics are as follows:
Gases fill their containers completely, but liquids may not.
Gases are lighter than equal volumes of liquids.
Gases are highly compressible, but liquids are essentially not compressible.
These differences are described in the appropriate areas of the following discussion concerning the properties and characteristics of fluids at rest. Also included are some of the factors which affect fluids in different situations.
Ordinarily, a machine is thought of as a complex device, such as an internal-combustion engine or a typewriter. These are machines, but so is a hammer, a screwdriver, or a wheel. A machine is any device with which work may be accomplished. Machines are used to transform energy, as in the case of a generator transforming mechanical energy into electrical energy. Machines are used to transfer energy from one place to another, as in the examples of the connecting rods, crankshaft, and reduction gears transferring energy from an aircraft's cylinder to its propeller.
A main purpose of machines is to multiply force; for example, a system of pulleys may be used to lift a heavy load. The pulley system enables the load to be raised by exerting a force which is smaller than the weight of the load.
Machines are also used to multiply speed. A good example is the bicycle, by which speed can be gained by exerting a greater force.
Finally, machines can be used to change the direction of a force. An example of this use is the flag hoist. A downward force on one side of the rope exerts an upward force on the other side, raising the flag toward the top of the pole.
There are only six simple machines. They are the lever, the pulley, the wheel and axle, the inclined plane, the screw, and the gear. However, physicists recognize only two basic principles in machines; namely, the lever and the inclined plane. The wheel and axle, the block and tackle, and gears may be considered levers. The wedge and the screw use the principle of the inclined plane.
An understanding of the principles of simple machines provides a necessary foundation for the study of compound machines, which are combinations of two or more simple machines.
The Lever
The simplest machine, and perhaps the most familiar one, is the lever. A seesaw is a familiar example of a lever in which one weight balances the other.
There are three basic parts in all levers; namely, the fulcrum F, a force or effort E, and a resistance R. Shown in figure 1-2 are the pivotal point F (fulcrum); the effort E, which is applied at a distance A from the fulcrum; and a resistance R, which acts at a distance a from the fulcrum. Distances A and a are the lever arms.
Figure 1-2. A simple lever.
Classes of Levers
The three classes of levers are illustrated in figure 1-3. The location of the fulcrum (the fixed or pivot point) with relation to the resistance (or weight) and the effort determines the lever class.
Figure 1-3. Three classes of levers.
First-Class Levers
In the first-class lever (A of figure 1-3), the fulcrum is located between the effort and the resistance. As mentioned earlier, the seesaw is a good example of the first-class lever. The amount of weight and the distance from the fulcrum can be varied to suit the need.
Second-Class Levers
The second-class lever (B of figure 1-3) has the fulcrum at one end; the effort is applied at the other end. The resistance is somewhere between these points. The wheelbarrow is a good example of a second-class lever.
Both first- and second-class levers are commonly used to help in overcoming big resistances with a relatively small effort.
Third-Class Levers
There are occasions when it is desirable to speed up the movement of the resistance even though a large amount of effort must be used. Levers that help accomplish this are third-class levers. As shown in C of figure 1-3, the fulcrum is at one end of the lever and the weight or resistance to be overcome is at the other end, with the effort applied at some point between. Third-class levers are easily recognized because the effort is applied between the fulcrum and the resistance.
This relationship can be stated in general terms: The length of the effort arm is the same number of times greater than the length of the resistance arm as the resistance to be overcome is greater than the effort that must be applied.
The mathematical equation for this relationship is:
A ÷ a = R ÷ E
A = Length of effort arm.
a = Length of resistance arm.
R = Resistance weight or force.
E = Effort force.
Remember that all distances must be in the same units, and all forces must also be in the same units.
Mechanical Advantage of Levers
Levers may provide mechanical advantages, since they can be applied in such manner that they can magnify an applied force. This is true of first and second-class levers. The third-class lever provides what is called a fractional disadvantage, i.e., one in which a greater force is required than the force of the load lifted.
Mechanical advantage machines are used throughout the aircraft to help the pilot or a motor or hydraulic or pneumatic system to accomplish a task where work is involved.
The study of machines, both simple and complex, is in one sense a study of the energy of mechanical work. This is true because all machines transfer input energy, or the work done on the machine to output energy, or the work done by the machine.
Work is done when a resistance is overcome by a force acting through a measurable distance. Two factors are involved: (1) Force and (2) movement through a distance. As an example, suppose a small aircraft is stuck in the snow. Two men push against it for a period of time, but the aircraft does not move. According to the technical definition, no work was done in pushing against the aircraft. By definition, work is accomplished only when an object is displaced some distance against a resistive force.
In equation form, this relationship is:
Work = Force (F) × distance (d).
The physicist defines work as work is force times displacement. Work done by a force acting on a body is equal to the magnitude of the force multiplied by the distance through which the force acts.
In the metric system, the unit of work is the joule, where one joule is the amount of work done by a force of one newton when it acts through a distance of one meter. That is,
1 joule = 1 newton-m
Hence we can write the definition in the form:
W (joules) = F (newtons) × d (meters)
If we push a box for 8 m across a floor with a force of 100 newtons, the work we perform is
W = Fd = 100 newtons × 8 m = 800 joules
How much work is done in raising a 500-kg (kilogram) elevator cab from the ground floor of a building to its tenth floor, 30 m (meters) higher? We note that the force needed is equal to the weight of the cab.
In the metric system, mass rather than weight is normally specified. To find the weight in newtons (the metric unit of force) of something whose mass in kilograms is known, the weight or gravitational force F = mg is used with g = 9.8 m/sec².
F (newtons) = m (kilograms) × g (9.8 m/sec²)
W (joules) = m (kilograms) × g (9.8 m/sec²) × d (meters)
W = Fd = mgd = 500 kg × 9.8 m/sec² × 30m
W = 147,000 joules
W = 1.47 10⁵ joules
Force Parallel to Displacement
If force is expressed in pounds and distances in feet, work will be expressed in foot-pounds (ft-lbs).
How much work is accomplished in lifting a 40-pound weight to a vertical height of 25 feet?
W = Fd
W = 40 lb × 25 ft
W = 1,000 ft-lb
How much work is accomplished in pushing a small aircraft into a hangar a distance of 115 feet if a force of 75 pounds is required to keep it moving?
W = 75 lb × 115 ft
Figure 1-4. Direction of work.
Force Not Parallel to Displacement
In the equation above, F is assumed to be in the same direction as d. If it is not, for example the case of a body pulling a wagon with a rope not parallel to the ground, we must use F for the component of the applied force that acts in the direction of the motion, figure l-4(B).
The component of a force in the direction of a displacement d is:
F cos Ѳ
where Ѳ is the angle between F and d. Hence the most general equation for work is:
W = Fd cos Ѳ
When F and d are parallel, Ѳ = 0° and cos Ѳ = 1, so that Fd cos Ѳ reduces to just Fd. When F and d are perpendicular, Ѳ = 90° and cos Ѳ = 0. so that no work is done. A force that is perpendicular to the motion of an object can do no work upon it. Thus gravity, which results in a downward force on everything near the earth, does no work on objects moving horizontally along the earth's surface. However, if we drop an object, as it falls to the ground, work is definitely done upon it.
In the case of an aircraft in level slow-flight at 60 KTS true airspeed, F must be used for the component of the force (thrust) that acts in the direction of motion. See figure 1-5.
Figure 1-5. Direction of work in level flight.
Friction is one of the most important aspects of life. Without friction it would be impossible to walk. One would have to shove oneself from place to place, and would have to bump against some obstacle to stop at a destination. Yet friction is a liability as well as an asset, and requires consideration when dealing with any moving mechanism.
In experiments relating to friction, measurement of the applied forces reveals that there are three kinds of friction. One force is required to start a body moving, while another is required to keep the body moving at constant speed. Also, after a body is once in motion, a definitely larger force is required to keep it sliding than to keep it rolling. Thus, the three kinds of friction may be classified as: (1) starting (static) friction, (2) sliding friction, and (3) rolling friction.
When an attempt is made to slide a heavy object along a surface, the object must first be broken loose or started. Once in motion, it slides more easily. The breaking loose force is proportional to the weight of the body. The force necessary to start the body moving slowly is designated F, and F is the force pressing the body against the surface (usually its weight). Since the nature of the surfaces rubbing against each other is important, they must be considered. The nature of the surfaces is indicated by the coefficient of starting friction, which is designated by the letter k. This coefficient can be established for various materials and is often published in tabular form.
Thus, when the load (weight of the object) is known, starting friction can be calculated by using the equation:
F = kF′
For example, if the coefficient of static friction of a smooth iron block on a smooth, horizontal surface is 0.3, the force required to start a 10-pound block would be 3 pounds; a 40-pound block, 12 pounds.
Starting friction for objects equipped with wheels and roller bearings is much smaller than that for sliding objects. Nevertheless. a locomotive would have difficulty getting a long train of cars in motion all at one time. Therefore, the couples between the cars are purposely made to have a few inches of play. When the engineer is about to start the train, he backs the engine until all the cars are pushed together. Then, with a quick start forward the first car is set in motion. This technique is employed to overcome the static friction of each wheel (as well as the inertia of each car). It would be impossible for the engine to start all of the cars at the same instant, for static friction, which is the resistance of being set in motion, would be greater than the force exerted by the engine. Once the cars are in motion, however, static friction is greatly reduced and a smaller force is required to keep the train in motion than was required to start it.
Dynamic or Sliding Friction
Sliding friction, sometimes called kinetic friction or dynamic friction, is the resistance to motion offered by an object sliding over a surface. It pertains to friction produced after the object has once been set into motion and is always less than starting friction. The amount of sliding resistance is dependent on the nature of the surface of the object, the surface over which it slides, and the normal force between the object and the surface. This resistive force may be computed by the formula:
F = µN
where: F is the resistive force due to friction expressed in pounds; N is the force exerted on or by the object perpendicular (normal) to the surface over which it slides; and µ (mu) is the coefficient of dynamic friction. (On a horizontal surface, N is equal to the weight of the object in pounds.) The area of the sliding object exposed to the sliding surface has no effect on the results. A block of wood, for example, will not slide any easier on one of the broad sides than it will on a narrow side, (assuming all sides have the same smoothness). Therefore, area does not enter into the equation above.
The coefficient of static friction will always be significantly higher than the coefficient of dynamic friction if other factors don't change. What application does this knowledge have for the pilot? Consider this: During landing deceleration, will there be more braking (stopping) ability with the brakes locked or with maximum braking but wheels turning? That's why anti-skid brake systems have been developed!
Rolling Friction
Resistance to motion is greatly reduced if an object is mounted on wheels or rollers. The force of friction for objects mounted on wheels or rollers is called rolling friction. This force may be computed by the same equation used in computing sliding friction, but the values of µ will be much smaller. For example, µ for rubber tires on concrete or macadam is about .02. The value of µ for roller bearings is very small, usually ranging from .001 to .003 and is often disregarded.
An aircraft with a gross weight of 79,600 lb is towed over a level concrete ramp. What force must be exerted by the towing vehicle to keep the airplane rolling after once set in motion?
F= µN
F = .02 × 79,600 = 1,592 lb
Power is a badly abused term. In speaking of power-driven equipment, people often confuse the term power with the ability to move heavy loads. This is not the meaning of power. A sewing machine motor is powerful enough to rotate an aircraft engine propeller providing it is connected to the crankshaft through a suitable mechanism. It could not rotate the propeller at 2,000 RPM, however, for it is not powerful enough to move a large load at a high speed. Power, thus, means rate of doing work. It is measured in terms of work accomplished per unit of time. In equation form, it reads:
Power = Work ÷ Time
Power = (Force × Distance) ÷ Time
P = Fd ÷ t
If force is expressed in pounds, distance in feet, and time in seconds, then power is given in ft–lbs/sec (foot-pounds per second). Time may also be given in minutes. If time in minutes is used in this equation, then power will be expressed in ft-lbs/min.
Power = (pounds × feet) ÷ seconds = ft-lbs/sec
Power = (pounds × feet) ÷ minutes = ft-lbs/min
An aircraft engine weighing 3,500 pounds was hoisted a vertical height of 7 feet in order to install it on an aircraft. The hoist was hand-powered and required 3 minutes of cranking to raise the engine. How much power was developed by the man cranking the hoist? (Neglect friction in the hoist.)
Power = Fd ÷ t
P = (3,500 pounds × 7 feet) ÷ 3 minutes
P = 8,167 ft-lbs/min.
Power is often expressed in units of horsepower. One horsepower is equal to 550 ft-lbs/sec or 33,000 ft-lbs/min.
1 HP = 550 ft-lbs/sec
In the hoist example above, calculate the horsepower developed by the man.
Power is rate of doing work:
P = W ÷ t
In the metric system the unit of power is the watt, where
1 watt = 1 joule/sec
The watt is the metric unit of power; thus a motor with a power output of 5,000 watts is capable of doing 5,000 joules of work per second.
A kilowatt (kw) is equal to 1,000 watts. Hence the above motor has a power output of 5 kw. For conversion, one HP is equal to 746 watts.
1 hp = 746 watts
How much time does the elevator cab weighing 500 kg need to ascend 30 meters if it is being lifted by a 5 kw motor? We rewrite P = W/ t in the form
t = W ÷ P
and then substitute W = 1.47 × 10⁵ joules and P = 5 × 10³ watts to find that
t = W ÷ P = (1.41 × 10⁵ joules) ÷ (5 × 10³ watts) = 29.4 sec
In many cases when work is done on an object, something is given to the object which it retains and which later enables it to do work. When a weight is lifted to a certain height, such as in the case of a trip-hammer or when a clock spring is wound, the object acquires, through having work done on it, the ability to do work itself. In storage batteries and gasoline, energy is stored which can be used later to do work. Energy stored in coal or food can be used to do work. Thus, energy can be defined as the ability to do work. The same units, ft-lbs or joules, are used to describe both work and energy.
In general, a change in energy is equal to the work done; the loss in energy of a body may be measured by the work it does, or the gain in energy of a body may be measured by the amount of work done on it. Energy which bodies possess is classified into two categories: (1) potential and (2) kinetic.
Potential energy may be classified into three groups: (1) that due to position, (2) that due to distortion of an elastic body, and (3) that which produces work through chemical action. Water in an elevated reservoir, and the lifted weight of a pile-driver are examples of the first group; a stretched rubber band or compressed spring are examples of the second group; and energy in coal, food, and batteries are examples of the third group.
Bodies in motion required work to put them in motion. Thus, they possess energy of motion. Energy due to motion is known as kinetic energy. A moving vehicle, a rotating flywheel, and a hammer in motion are examples of kinetic energy.
Energy is expressed in the same units as those used to express work. The quantity of potential energy possessed by an elevated weight may be computed by the equation:
Potential Energy = Weight × Height
If weight is given in pounds and height in feet, the final unit of energy will be ft-lbs (foot-pounds).
Example: An aircraft with a gross weight of 110,000 pounds is flying at an altitude of 15,000 feet above the surface of the earth. How much potential energy does the airplane possess with respect to the earth?
PE = 110,000 × 15,000
PE = 1,650,000,000 ft-lbs
The most common forms of energy are heat (thermal), mechanical, electrical, and chemical. The various forms of energy can be changed, or transformed, into another form in many different ways. For example, in the case of mechanical energy, the energy of work done against friction is always converted into heat energy, and the mechanical energy that turns an electric generator develops electrical energy at the output of the generator.
Force And Motion Of Bodies
The study of the relationship between the motion of bodies or objects and the forces acting on them is often called the study of force and motion or dynamics. In a more specific sense, the relationship between velocity, acceleration, and distance is known as kinematics.
Uniform Motion
Motion may be defined as a continuing change of position or place, or as the process in which a body undergoes displacement. When an object is at different points in space at different times, that object is said to be in motion, and if the distance the object moves remains the same for a given period of time, the motion may be described as uniform. Thus, an object in uniform motion always has a constant speed.
Speed and Velocity
In everyday usage, speed and velocity often mean the same thing. In physics they have definite and distinct meanings. Speed refers to how fast an object is moving, or how far the object will travel in a specific time. The speed of an object tells nothing about the direction an object is moving. For example, if the information is supplied that an airplane leaves New York City and travels 8 hours at a speed of 150 MPH, this information tells nothing about the direction in which the airplane is moving. At the end of 8 hours, it might be in Kansas City, or if it traveled in a circular route, it could be back in New York City.
Velocity is that quantity in physics which denotes both the speed of an object and the direction in which the object moves. Velocity can be defined as the rate of motion in a particular direction, which is a vector quantity.
Acceleration is defined by the physicist as the rate of change of velocity. If the velocity of an object is increased from 20 MPH to 30 MPH, the object has been accelerated. If the increase in velocity is 10 MPH in 5 seconds, the rate of change in velocity is 10 MPH in 5 seconds, or 2 MPH/sec.
Expressed as an equation,
a = ∆V ÷ ∆t
a = (Vf − Vi ) ÷ ∆t
a = acceleration
Vf = the final velocity (30 MPH)
Vi = the initial velocity (20 MPH)
∆t = change in time or the elapsed time
∆V = change in velocity
The example used can be expressed as follows:
A = (30 MPH − 20 MPH) ÷ 5 sec
A = 2 MPH/sec
If the object accelerated to 22 MPH in the first second, 24 MPH in the next second, and 26 MPH in the third second, the change in velocity each second is 2 MPH. The acceleration is said to be constant, and the motion is described as uniformly accelerated motion. Since velocity denotes both speed and direction, a change in direction of a mass is considered to be an acceleration. An aircraft executing a standard rate turn (3 degrees per second) is considered to be in uniformly accelerated motion.
If a body has a velocity of 3 MPH at the end of the first second of its motion, 5 MPH at the end of the next second, and 8 MPH at the end of the third second, its motion is described as acceleration, but it is variable accelerated motion.
When a magician snatches a tablecloth from a table and leaves a full setting of dishes undisturbed, he is not displaying a mystic art; he is demonstrating the principle of inertia.
Inertia is responsible for the discomfort felt when a car is brought to a sudden halt in the parking area and the passengers are thrown forward in their seats, and inertia provides the feeling of being pushed back into the seat felt by occupants of a rapidly accelerating aircraft during takeoff. Inertia is a property of matter. This property of matter is described by Newton's first law of motion, which states:
Objects at rest tend to remain at rest; objects in motion tend to remain in motion at the same speed and in the same direction.
Bodies in motion have the property called momentum. A body that has great momentum has a strong tendency to remain in motion and is therefore hard to stop. For example, a train moving at even low velocity is difficult to stop because of its large mass. Newton's second law applies to this property. It states:
When forces act upon a body, the momentum of the body can be changed. The rate of change of momentum of the body is proportional to the vector sum of the forces (net force) applied to the body. The momentum (p) of a body is defined as the product of its mass times its velocity.
Momentum = mass × velocity or,
p = mV
Now if a force is applied, the momentum changes at a rate equal to the vector sum of the forces applied or the new force (∑F):
∑F = rate of change of momentum
∑F = (Mf − Mi) ÷ Δt
Substituting mV for M:
∑F = (mfVf − miVi) ÷ Δt
Since the mass does not usually change, mf = mi = m. Then
∑F = (mVf − mVi) ÷ Δt
∑F = m × [(Vf − Vi) ÷ Δt]
From the previous section the second term is recognized as acceleration. Then the second law becomes:
F = ma
If the only force acting upon a body near the earth is the gravitational force (its weight), then the body will experience an acceleration which is called the acceleration due to gravity, usually designated as g, and is equal in English units to 32 ft/SEC² , directed toward the center of the earth. The weight W of a body is the commonly used name for the force due to gravity acting upon that body, and if this is the only force acting upon the body of mass, m, that body accelerates toward the center of the earth at 32 feet per second per second. If these ideas are used along with Newton's second law:
F = ma becomes W = mg, which can be rearranged as
m = W ÷ g
If the mass m of a body is known, then the weight W of that body near the earth is given by:
W = mg
If the weight W of a body near the surface of the earth is known, then the mass m of that body is given by:
Distance between the bodies being attracted to each other affects the strength of the attracting force (mass attraction). For example, an airplane that weighs 3,000 pounds at sea level will weigh about 3/4 pound less at 10,000' ASL, but its mass remains the same.
The following examples illustrate the use of this formula.
A train weighs 32,000 lbs. and is traveling at 10 ft/sec. What force is required to bring it to rest in 10 seconds?
F = (W ÷ g) × a
= (W ÷ g) × [(Vf − Vi) ÷ t]
= (32,000 ÷ 32) × [(0 − 10) ÷ 10]
= [32,000 × (-10)] ÷ (32 × 10)
= -1,000 lbs
The negative sign means that the force must be applied against the train's motion.
An aircraft weighs 6,400 pounds. How much force is needed to give it an acceleration of 6 ft/sec² (neglecting drag)?
= (6,400 × 6) ÷ 32 = 1,200 lb
Newton's third law of motion is often called the law of action and reaction. It states that for every action there is an equal and opposite reaction. This means that if a force is applied to an object, the object will supply a resistive force exactly equally to and in the opposite direction of the force applied. It is easy to see how this might apply to objects at rest. For example, as a man stands on the floor, the floor exerts a force against his feet exactly equal to his weight. But this law is also applicable when a force is applied to an object in motion.
When an aircraft propeller pushes a stream of air backward with a force of 500 pounds, the air pushes the blades forward with a force of 500 pounds. This forward force causes the aircraft to move forward. In like manner, the discharge of exhaust gases from the tailpipe of a turbine engine is the action which causes the aircraft to move forward.
The three laws of motion which have been discussed here are closely related. In many cases, all three laws may be operating on a body at the same time.
In order to keep straight in one's mind the relationships between Newton's three laws of motion, it is well to remember that Newton's third law involves interactions between two or more bodies. The action and reaction forces act on the different bodies which are also producing forces which are interacting with the bodies. Thus, when considering the resulting effect on the bodies, the net force, or vector sum of all the forces must be considered. Newton's second law describes the effect of all the forces which act on one body (mass). Newton's first law describes the action of a body when there is no net force acting upon it.
The term vibration indicates periodic, continuing motion, usually of a solid object, but may also apply to a liquid (wave) or a gas (sound). The motion may be in the form of a pulse (a motion that comes along once-in-a-while) or waveforms, where any part of the vibrating mass is continuously moving.
If we give one end of a stretched string a quick shake, a kink or pulse travels down the string at some velocity v (figure 1-6). If the string is uniform and completely flexible, the pulse keeps the same shape and velocity. The velocity of the pulse depends on the properties of the string, its density and flexibility, and on how tightly it is stretched rather than on the shape of the pulse or how it is produced.
Figure 1-6. A pulse moves along a stretched string with a constant velocity v.
The energy content of a moving pulse is partly kinetic and partly potential. As the pulse travels, its forward part is moving upward and its rear part is moving downward (figure 1-7). Because the string has mass, there is kinetic energy associated with these up-and-down motions. Because the stretched string had to be stretched further to deform it (by pulling against the tension), work was done to form the pulse and the string, accordingly, possesses potential energy.
Figure 1-7. The forward part of a traveling pulse is moving upward and the rear part Is moving downward.
When the pulse reaches the end of the string, some or all of the pulse's energy may be reflected, causing all or a portion of the pulse to travel back toward its starting point. Depending on how the string is held in place, the reflected pulse may be inverted (upside-down) or erect (right-side-up). Or, the energy of the pulse may all be absorbed by the support, in which case the pulse will disappear but the support will have to deal with the energy it has absorbed.
A good example of pulsing vibration is that produced by the internal combustion engine. As each cylinder fires, a pulse of motion is delivered to the crankshaft and to the propeller. Because of Newton's third law, an equal and opposite pulse is delivered via the engine mount to the fuselage.
In a periodic wave, one pulse follows another in regular succession, so a certain waveform (the shape of the individual waves) is repeated at regular intervals. Periodic waves usually have sinusoidal waveforms (the same appearance as a graph of sin x (or cos x) versus the angle x (figure 1-8).
Figure 1-8. Most periodic waves have sinusoidal waveforms.
Sinusoidal waveforms are common in matter because the particles of matter undergo simple harmonic motion when displaced by the passage of a wave. Because the link between two particles of matter is not totally rigid, the movement of one particle causes the next particle to move a moment later (like a row of toppling dominoes).
Some related terms are used to describe periodic waves: wave velocity describes the distance each wave moves per second, wavelength (symbolized by the Greek letter lambda) is the distance between adjacent crests or troughs, frequency is the number of waves that pass a given point per second (cycles per second, or Hertz, Hz), period is the time it takes for one complete cycle to pass a given point (the reciprocal of the frequency), amplitude is the maximum displacement of the particle from its normal position. The amplitude of a wave in a stretched string is the height of the crests above or the troughs below the original line of the string.
Standing Waves
When a string whose ends are fixed in place is plucked, the string will vibrate in one or more loops (figure 1-9). These standing waves may be thought of as being the result of waves that travel down the string in both directions, are reflected at the ends, proceed across the string to the opposite ends and are again reflected, and so on.
Figure 1-9. Standing waves in a stretched string.
Pilots should attempt to visualize how the types of vibrations being described here can travel through the various parts of the aircraft.
Principle of Superposition
Standing waves in a mass interact with each other according to the principle of superposition: When two or more waves of the same nature travel past a point at the same time, the displacement at that point is the sum of the instantaneous displacements of the individual waves.
The principle of superposition holds for all types of waves. What it means is that every wave train proceeds independently of any other that may also be present, but the effect of waves present at any point is the additive result of all waves present. For example, should two waves with the same wavelength come together in such a way that crest aligns with crest and trough aligns with trough, the resulting composite wave will have an amplitude greater (the sum of the two amplitudes) than that of either of the original waves. The waves are said to interfere constructively with each other. But if the waves come together so that one wave's crest aligns with the other's trough, the effect is cancelling and the amplitude will be decreased (to zero, if the amplitudes of the individual waves are equal). In this condition, the waves interfere destructively with each other. See figure 1-10.
Figure 1-10 (A). Constructive interference. (B) Destructive interference.
Consider for a moment a string where nodes occur at each end of the string, as in figure 1-9. The lowest possible frequency of oscillation corresponds to the longest wavelength, λ = 2L, as depicted by the top waveform in figure 1-9. Higher frequencies correspond to the shorter wavelengths. The lowest frequency is called the fundamental frequency. The higher frequencies are 2, 3, 4, etc. times higher (always whole numbers) and are called overtones.
The fundamental frequency and overtones of a mass are its natural frequencies of vibration. Pulsing a mass will cause it to vibrate at one or more of these frequencies. Eventually, internal friction in the mass will cause the various vibrations to die out.
However, the vibration can be caused to continue by applying to the mass a periodic force whose frequency is exactly the same as that of one of the mass's natural frequencies. If the force applied at the correct frequency is greater than that needed to overcome internal friction, the amplitude of the standing wave will increase until the mass ruptures (a column of soldiers can destroy a flimsy bridge by marching across it in step with one of the bridge's natural frequencies although the bridge is capable of holding up the static load of the soldiers' weight). This phenomenon is called resonance and is based upon the concept of superposition of waves.
When periodic impulses are given to a mass at frequencies other than its natural ones, hardly any response occurs. The pilot must keep in mind that each structural part of the aircraft has its own natural frequencies of oscillation, at which a small amount of excitation can cause large amplitudes of oscillation. It is possible that an aircraft structure (as large as the fuselage itself or as small as the hat-rack structure) will have a resonant frequency the same as certain vibrations from the engine, propeller or even the air in the intake duct. For this reason, aircraft undergo extensive flight and vibration testing to minimize the chances of resonance excitation. For example, a propeller should never be used on an aircraft without first determining that it has been tested and certified for use with that particular engine and airframe combination.
Anti-skid/Autobrake Systems—Boeing 757 Wild, T.; Transport Category Aircraft Systems; IAP, Inc. 1990, pages 167-170.
Unit conversions—There are many sources, such as: Handbook of Chemistry and Physics, any edition.
Gravity effects and further study of physical properties of matter.
− Any high school or beginning college physics textbook.
− Airframe and Powerplant Mechanics General Handbook, Chapter 7; IAP, Inc., Publ.
Study Questions and Problems
Neglecting drag, how much power is needed to cause a 2500 pound airplane to climb at 1000 ft/min? Express your answer in ft-lbs/ min, watts, and HP.
Three minutes after takeoff, how much potential energy will the aircraft of Question #1 possess (neglect remaining fuel in the tanks)?
What kind of energy does the aircraft of Question #2 possess?
What are the states of matter? Define or describe each.
What distinguishes a liquid from a gas and what is a fluid?
Show the value of pressure of the standard day atmosphere at sea level in five different units of measure.
Show the value of temperature of the standard day atmosphere at sea level in four different units of measure.
What kind of a lever is your forearm?
What kind of a lever is the aircraft control yoke, with respect to aileron movement?
What kind of a lever is a hydraulic wobble pump handle?
If you fell from an airplane at a high altitude where the air was so thin that there was negligible drag, how fast would you be falling after 5 seconds, in ft/sec, MPH, KTS, and km/hr?
What are the differences between inertia and momentum?
Aircraft Engine Types and Construction
The Heat Engine
For an aircraft to remain in level unaccelerated flight, a thrust must be provided that is equal to and opposite in direction to the aircraft drag. This thrust, or propulsive force, is provided by a suitable type of heat engine.
All heat engines have in common the ability to convert fuel (chemical energy) into heat energy, then into mechanical energy, by the flow of some fluid mass through the engine. In all cases, the heat energy is released at a point in the cycle where the pressure is high, relative to atmospheric.
These engines are customarily divided into groups or types depending upon:
The working fluid used in the engine cycle.
The means by which the mechanical energy is transmitted into a propulsive force.
The method of compressing the engine working fluid.
The types of engines are illustrated in figure 2-1.
Figure 2-1. Types of engines.
The propulsive force is obtained by the displacement of a working fluid (not necessarily the same fluid used within the engine) in a direction opposite to that in which the airplane is propelled. This is an application of Newton's third law of motion. Air is the principal fluid used for propulsion in every type of powerplant except the rocket, in which only the by-products of combustion are accelerated and displaced.
The propellers of aircraft powered by reciprocating or turboprop engines accelerate a large mass of air through a small velocity change. The fluid (air) used for the propulsive force is a different quantity than that used within the engine to produce the mechanical energy. Turbojets, ramjets, and pulse-jets accelerate a smaller quantity of air through a large velocity change. They use the same working fluid for propulsive force that is used within the engine. A rocket carries its own oxidizer rather than using ambient air for combustion. It discharges the gaseous by-products of combustion through the exhaust nozzle at an extremely high velocity.
Engines are further characterized by the means of compressing the working fluid before the addition of heat. The basic methods of compression are:
The turbine-driven compressor (turbine engine).
The positive displacement, piston-type compressor (reciprocating engine).
Ram compression due to forward flight speed (ramjet).
Pressure rise due to combustion (pulse-jet and rocket).
A more specific description of the major engine types used in commercial aviation is given later in this chapter.
Comparison of Aircraft Powerplants
In addition to the differences in the methods employed by the various types of powerplants for producing thrust, there are differences in their suitability for different types of aircraft. The following discussion points out some of the important characteristics that determine their suitability.
All engines must meet certain general requirements of efficiency, economy, and reliability. Besides being economical in fuel consumption, an aircraft engine must be economical (the cost of original procurement and the cost of maintenance) and it must meet exacting requirements of efficiency and low weight per horsepower ratio. It must be capable of sustained high-power output with no sacrifice in reliability; it must also have the durability to operate for long periods of time between overhauls. It needs to be as compact as possible, yet have easy accessibility for maintenance. It is required to be as vibration free as possible and be able to cover a wide range of power output at various speeds and altitudes.
These requirements dictate the use of ignition systems that will deliver the firing impulse to the spark plugs or igniter plugs at the proper time in all kinds of weather and under other adverse conditions. Fuel-metering devices are needed that will deliver fuel in the correct proportion to the air ingested by the engine regardless of the attitude, altitude, or type of weather in which the engine is operated. The engine needs a type of oil system that delivers oil under the proper pressure to all of the operating parts of the engine when it is running. Also, it must have a system of damping units to damp out the vibrations of the engine when it is operating.
Power and Weight
The useful output of all aircraft powerplants is the force thrust, the force which propels the aircraft. Since the reciprocating engine is rated in BHP (brake horsepower) and the gas turbine engine is rated in pounds of thrust, no direct comparison can be made. However, since the reciprocating engine/propeller combination receives its thrust from the propeller, a comparison can be made by converting the horsepower developed by the reciprocating engine to thrust.
If desired, the thrust of a gas turbine engine can be converted into THP (thrust horsepower). But it is necessary to consider the speed of the aircraft. This conversion can be accomplished by using the formula:
THP = [thrust × aircraft speed (MPH]) ÷ 375 mile-pounds per hour
The value 375 mile-pounds per hour is derived from the basic horsepower formula as follows:
1 HP = 33,000 ft-lb per minute
33,000 ft-lb/min × 60 min/1hr = 1,980,000 ft-lb per hour
1,980,000 ft-lb/hr ÷ 5,280 ft/mi = 375 mile-pounds per hour
One horsepower equals 33,000 ft-lb per minute or 375 mile-pounds per hour. Under static conditions, thrust is figured as equivalent to approximately 2.6 pounds per hour.
If a gas turbine is producing 4,000 pounds of thrust and the aircraft in which the engine is installed is traveling at 500 MPH, the THP will be:
(4,000 × 500) ÷ 375 = 5,333.33 THP
It is necessary to calculate the horsepower for each speed of an aircraft, since the horsepower varies with speed. Therefore, it is not practical to try to rate or compare the output of a turbine engine on a horsepower basis.
The aircraft engine operates at a relatively high percentage of its maximum power output throughout its service life. The aircraft engine is at full power output whenever a takeoff is made. It may hold this power for a period of time up to the limits set by the manufacturer. The engine is seldom held at a maximum power for more than 2 minutes, and usually not that long. Within a few seconds after lift-off, the power is reduced to a power that is used for climbing and that can be maintained for longer periods of time. After the aircraft has climbed to cruising altitude, the power of the engine(s) is further reduced to a cruise power that can be maintained for the duration of the flight.
If the weight of an engine per brake horsepower (called the specific weight of the engine) is decreased, the useful load that an aircraft can carry and/or the performance of the aircraft obviously are increased. Every excess pound of weight carried by an aircraft engine reduces its performance. Tremendous gains in reducing the weight of the aircraft engine through improvement in design and metallurgy have resulted in reciprocating engines now producing approximately 1 HP for each pound of weight.
The basic parameter for describing the fuel economy of aircraft engines is usually specific fuel consumption. Specific fuel consumption for turbojets and ramjets is the fuel flow (lbs/hr) divided by thrust (lbs), and for reciprocating engines the fuel flow (lbs/ hr) divided by brake horsepower. These are called thrust specific fuel consumption and brake specific fuel consumption, respectively. Equivalent specific fuel consumption is used for the turboprop engine and is the fuel flow in pounds per hour divided by a turboprop's equivalent shaft horsepower. Comparisons of efficiency can be made between the various engines on a specific fuel consumption basis.
At low speed, the reciprocating and turbopropeller engines have better economy than the turbojet engines. However, at high speed, because of losses in propeller efficiency, the reciprocating or turbopropeller engine's efficiency becomes less than that of the turbojet. Figure 2-2 shows a comparison of average thrust specific fuel consumption of three types of engines at rated power at sea level.
Figure 2-2. Comparison of fuel consumption for three types of engines at rated power at sea level.
Durability and Reliability
Durability and reliability are usually considered identical factors since it is difficult to mention one without including the other. An aircraft engine is reliable when it can perform at the specified ratings in widely varying flight attitudes and in extreme weather conditions. Standards of powerplant reliability are agreed upon by the FAA, the engine manufacturer, and the airframe manufacturer. The engine manufacturer ensures


The main JMeter frame, containing the menu bar, test tree, and an area for JMeter component GUIs.
Create a new JMeter frame.
Close the currently selected menu.
Specify whether or not the Edit|Add menu item should be enabled.
Set the menu that should be used for the Edit|Add menu.
Specify whether or not the Edit menu item should be enabled.
Set the menu that should be used for the Edit menu.
Specify whether or not the File|Load menu item should be enabled.
Specify whether or not the File|Revert item should be enabled.
Specify whether or not the File|Save menu item should be enabled.
Show a dialog indicating that JMeter threads are stopping on a particular host.
Called when a test is ended on the local system.
Called when a test is ended on the remote system.
Called when a test is started on the local system.
Called when a test is started on a specific host.
Default constructor for the JMeter frame. This constructor will not properly initialize the tree, so don't use it.
Called when a test is started on the local system. This implementation sets the running indicator and ensures that the menubar is enabled and in the running state.
Called when a test is started on a specific host. This implementation sets the running indicator and ensures that the menubar is in the running state.
Called when a test is ended on the local system. This implementation disables the menubar, stops the running indicator, and closes the stopping message dialog.
Called when a test is ended on the remote system. This implementation stops the running indicator and closes the stopping message dialog.


Springtime in DC. Nats losing, allergy-inducing cherry blossoms and hordes of elevator-standing tourists.
What is my personal sign of spring? Jazz Appreciation Month. That's right. Appreciate me. There are so many great events going on this month it's overwhelming. Check out some examples on my new favorite blog http://dcjazzshows.blogspot.com/.
My dear Diev and I were out today at legendary Bucky Pizzarelli's masterclass and were thrilled to get to meet him in person after the show. What an amazing guitarist, and a cheerful guy to be around. I think he smiled through the whole set with bassist Tommy Cecil.
As for my own contributions to appreciating jazz this month, I will be performing tonight with the Howard University Jazz Ensemble at Westminster Church in SW DC. We will also be performing Sunday at the Anacostia Community Museum.
I am thrilled that my composition and arrangement "Lightning" will be performed by HU's (Downbeat Award-Winning!) Afro-Blue, together with the Smithsonian Jazz Masterworks Orchestra on April 24th at 5pm in the Sylvan Theatre on the National Mall for the closing weekend of JAM activities. Many thanks to fabulous arranger and donut-bringer Scott Silbert for his tips on the arrangement!
Please, if you can, appreciate some real live jazz this month.


text:
Q2 Music's 'Become Ocean' Listening Party with John Luther Adams
Thursday January 26 2023 • 5:18pm - 5:18pm ET
Q2 Music's Helga Davis and composer John Luther Adams in The Greene Space
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John Luther Adams's 2014 Pulitzer Prize-winning Become Ocean "may be the loveliest apocalypse in musical history," according to Alex Ross of The New Yorker.
To celebrate the Seattle Symphony Orchestra's recording of the work, set to be released September 30, Q2 Music hosted an exclusive event to experience Become Ocean in engulfing 5.1 surround-sound, just as the composer says it was meant to be heard. Divided evenly by three cresting, crashing crescendos, Become Ocean presents Adams's unique synthesis of surface lushness with roiling, subterranean might.
The evening began with a conversation between Adams and Q2's Helga Davis about the inspiration behind the piece and its ambitious new recording by the Seattle Symphony, under the direction of Ludovic Morlot.
Watch on-demand video of the entire event below:
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Aizuri Quartet: Song Emerging
WQXR's Artist Propulsion Lab Concert Series


text:
Q: Not returning any row from table I am fetching data from database there are 6 rows in table but it is not showing any output in program. What may be the problem my code is below.
It is not showin any error in console.
public class smsDAO {

Session session = HibernateUtil.getSessionFactory().openSession();
public List<SmsGateway> fetchAll() {
        System.out.println("Calling fetchA b");
        Transaction tx = session.beginTransaction();
        List<SmsGateway> sms = null;
        try {
            sms = session.createQuery("FROM sms_gateway").list();
            tx.commit();
            for (SmsGateway s : sms) {
                System.out.println(s.getDescription() + " " + s.getUrl1());
            }
        } catch (HibernateException e) {
            if (tx != null) {
                tx.rollback();
            }
        } finally {
            session.close();
        }
        System.out.println("Calling fetchA re  ");
        return sms;
    }
}

A: The console is not shwing any error because you deliberatey chose to ignore the exceptions thrown. Replace
    catch (HibernateException e) {
        if (tx != null) {
            tx.rollback();
        }
    }

by
    catch (HibernateException e) {
        e.printStackTrace();
        if (tx != null) {
            tx.rollback();
        }
        throw e;
    }

And re-read the chapter about HQL in the documentation. HQL always uses names of entities and their mapped field. It never uses table names. So the query should be
select s from SmsGateway s

Also, respect the Java naming conventions: Classes start with an uppercase letter.

redpajama_set_name: RedPajamaStackExchange


JOE PUBLIC held on desperately to a Marley Quamina goal to edge arch- rivals Carib FC 1-0 and move into the final of the Emerald Apartments & Plaza-sponsored Eastern Football Association's FA Trophy series.
BON AIR FC took revenge for their loss to Parliament FC in last season's final with a 1-0 win over the league champions to take home the Community Shield at the opening of the 43rd edition of the Eddie Hart Football League (EHFL) at the Eddie Hart Savannah (EHS) last Sunday.
Clint Marcelle Football Academy, Defence Force and Trendsetter Hawks were among those taking the top honours as the 14th edition of the Republic Bank RightStart Cup Youth Football Tournament came to an interesting and entertaining conclusion on Sunday at the Queen's Park Savannah.
A double strike by "bound-to-score" striker Carlon Hughes propelled frontrunners Mayaro Spurs to a 2-0 victory over fellow contenders Mafeking United last Sunday as action continued in the Senior Division of the 2009 bpTT Mayaro Football League.
Over forty of the best teams from every point in Trinidad and Tobago will come together for the finale of the Republic Bank Right Start Cup Youth Football Tournament, which takes place on Sunday 9th August 2009 at the Casuals Corner, Queen's Park Savannah. After seven preliminary rounds, the top ten teams from each age group were qualified to play in the finals.
This was announced by president of the EHFL, Eddie Hart when he addressed clubs on Thursday night at the Bally Street Community Centre in Tacarigua on the 2009 season. According to Hart, he and the Chief Defence of Staff Brigadier Edmund Dillon, a past player in the EHFL, will complete the party that will be taking the salute at the EHS this afternoon.
KEVON CORNWALL scored a hat-trick of goals to lead Joe Public on their triumphant march in the FA Trophy series in the Emerald Apartments and Plaza-sponsored Eastern Football Association.
THE 43rd edition of the popular Eddie Hart League opens on Sunday at the Eddie Hart Grounds, Tacarigua at 2 pm with a parade of teams. Eighty teams have registered to participate in the league which consists of six divisions — Under-13, Under-15, Under-19, Under-21, Premier and women's.
VALTRIN scored a shock 1-0 victory over Carib FC in the Premiership Division of the Emerald Apartments & Plaza-sponsored Eastern Football Association for the Arthur "Jap" Brown Memorial Trophy.


text:
Shaitan elchini  è un ragno appartenente alla famiglia Gnaphosidae.

È l'unica specie nota del genere Shaitan.

Etimologia
Il nome del genere deriva dal termine arabo Shaitan, che significa demone, diavolo, e da cui in italiano deriva Satana.

Il nome proprio della specie è in onore dell'aracnologo azero Elchin Fizuli Huseinov, per i suoi contributi alla tassonomia e all'etologia dei ragni del Caucaso.

Distribuzione
L'unica specie oggi nota di questo genere è stata rinvenuta nel Kazakistan meridionale (20 km a nord di Taraz, nella catena montuosa dei monti Karatau) e in Azerbaigian (nel distretto di Abşeron).

Tassonomia
Dal 2013 non sono stati esaminati altri esemplari, né sono state descritte sottospecie al 2015.

Note

Bibliografia
 Kovblyuk, M.M., Kastrygina, Z.A. & Marusik, Y.M., 2013 - A new genus Shaitan elchini gen. et sp.n. (Aranei: Gnaphosidae) from Azerbaijan and Kazakhstan. Arthropoda Selecta vol.22, pp. 145–151. PDF

Altri progetti

Collegamenti esterni

Gnaphosidae
Taxa classificati da Jurij Marusik