IFR AIRCRAFT- An aircraft conducting flight in accordance with instrument flight rules. 

IFR CONDITIONS- Weather conditions below the minimum for flight under visual flight rules. 

(See INSTRUMENT METEOROLOGICAL CONDITIONS.) 

IFR DEPARTURE PROCEDURE- (See IFR TAKEOFF MINIMUMS AND DEPARTURE PROCEDURES.) 

(Refer to AIM.) 

IFR FLIGHT- (See IFR AIRCRAFT.) 

IFR LANDING MINIMUMS- (See LANDING MINIMUMS.) 

IFR MILITARY TRAINING ROUTES (IR)- Routes used by the Department of Defense and associated Reserve and Air Guard units for the purpose of conducting low-altitude navigation and tactical training in both IFR and VFR weather conditions below 10,000 feet MSL at airspeeds in excess of 250 knots IAS. 

IFR TAKEOFF MINIMUMS AND DEPARTURE PROCEDURES- Title 14 Code of Federal Regulations Part 91, prescribes standard takeoff rules for certain civil users. At some airports, obstructions or other factors require the establishment of nonstandard takeoff minimums, departure proce- dures, or both to assist pilots in avoiding obstacles during climb to the minimum en route altitude. Those airports are listed in FAA/DOD Instrument Approach Procedures (IAPs) Charts under a section entitled “IFR Takeoff Minimums and Departure Procedures.” The FAA/DOD IAP chart legend illustrates the symbol used to alert the pilot to nonstandard takeoff minimums and departure procedures. When depart- ing IFR from such airports or from any airports where there are no departure procedures, DPs, or ATC facilities available, pilots should advise ATC of any departure limitations. Controllers may query a pilot to determine acceptable departure directions, turns, or headings after takeoff. Pilots should be familiar with the departure procedures and must assure that their aircraft can meet or exceed any specified climb gradients. 

IF/IAWP- Intermediate Fix/Initial Approach Way- point. The waypoint where the final approach course of a T approach meets the crossbar of the T. When 

designated (in conjunction with a TAA) this waypoint will be used as an IAWP when approaching the airport from certain directions, and as an IFWP when beginning the approach from another IAWP. 

IFWP- Intermediate Fix Waypoint 

ILS- (See INSTRUMENT LANDING SYSTEM.) 

ILS CATEGORIES- 1. Category I. An ILS approach procedure which provides for approach to a height above touchdown of not less than 200 feet and with runway visual range of not less than 1,800 feet.- 2. Special Authorization Category I. An ILS approach procedure which provides for approach to a height above touchdown of not less than 150 feet and with runway visual range of not less than 1,400 feet, HUD to DH. 3. Category II. An ILS approach procedure which provides for approach to a height above touchdown of not less than 100 feet and with runway visual range of not less than 1,200 feet (with autoland or HUD to touchdown and noted on authorization, RVR 1,000 feet).- 4. Special Authorization Category II with Reduced Lighting. An ILS approach procedure which provides for approach to a height above touchdown of not less than 100 feet and with runway visual range of not less than 1,200 feet with autoland or HUD to touchdown and noted on authorization (no touchdown zone and centerline lighting are required).- 5. Category III: 

a. IIIA.-An ILS approach procedure which provides for approach without a decision height minimum and with runway visual range of not less than 700 feet. 

b. IIIB.-An ILS approach procedure which provides for approach without a decision height minimum and with runway visual range of not less than 150 feet. 

c. IIIC.-An ILS approach procedure which provides for approach without a decision height minimum and without runway visual range minimum. 

IM- (See INNER MARKER. ) 

IMC- (See INSTRUMENT METEOROLOGICAL CONDITIONS.) 

IMMEDIATELY- Used by ATC or pilots when such action compliance is required to avoid an imminent situation. 

