2004 aviation accident
Kish Air Flight 7170 was a scheduled international passenger flight from Kish Island in Iran to Sharjah, United Arab Emirates, operated by Iranian airline Kish Air. On February 10, 2004, the aircraft serving the route, a Fokker 50, lost control and crashed onto terrain while on approach to Sharjah International Airport. A total of 43 out of 46 people on board were killed in the crash, making it the deadliest air disaster involving the Fokker 50.
The Emirati General Civil Aviation Authority concluded that the accident was mainly caused by pilot error. The captain of the flight suddenly asked the first officer to conduct the approach. This took the unprepared first officer by surprise, causing him to be nervous and eventually led to the aircraft being high on approach. Realizing this, the captain took over the control and decided to pull the thrust until it reached the ground range to quickly decrease their altitude. However, the captain accidentally caused the thrust to enter the reverse range, deploying the reverser in mid-air and ultimately caused the aircraft to crash.
Flight 7170 crashed in a similar manner with Luxair Flight 9642, another accident involving the Fokker F50 which had crashed just two years prior in Luxembourg. The crash of Flight 9642 had resulted in the mandatory recommendation for every Fokker F50 operators to send their aircraft back to the manufacturer for modification. The striking resemblances between both disasters caused authorities to urge non-compliant operators to immediately transport their Fokker F50 for the updated design.
Aircraft.
The aircraft involved was a Fokker 50, registered EP-LCA. It first flew on 25 January 1993 with Lufthansa CityLine as D-AFFJ, then to Air Nostrum for Iberia as EC-GKU prior to being delivered to Kish Air on 1 March 2002. The aircraft had followed an "A" check on 24 December 2003 and was due to another check on 31 April 2004. The aircraft was equipped with two Pratt &amp; Whitney Canada engines and two Dowty Propellers.
Flight.
Flight 7170 was a scheduled international passenger flight from the Iranian resort island of Kish to Sharjah International Airport in United Arab Emirates. On 10 February, the aircraft was scheduled to take off from Kish with 42 passengers and 6 crew members on board. The commander of the flight was Captain Ahmed Hosseini and his co-pilot was First Officer Nemat Panahian. The weather and visibility at Sharjah were in good condition. The flight was supposed to take about 35 minutes. It eventually took off from Kish at early noon. The take-off phase was uneventful.
During the enroute phase, shortly before the aircraft started its descent to Sharjah, Captain Hosseini asked First Officer Panahian to switch roles, making Panahian the pilot who was responsible for the controls. First Officer Panahian was surprised by this decision as this was not what the pilots had planned earlier, eventually declining the captain's order stating that he was not confident enough on his ability to conduct the approach to the airport. Captain Hosseini, however, refused to accept his answer and insisted Panahian be the pilot flying, stating that he would provide assistance during the approach. First Officer Panahian reluctantly accepted this and became the pilot flying for the approach phase.
Approach.
As the aircraft approached the airport, the crew initiated the approach briefing and read the checklist. During the approach, Captain Hosseini kept giving advice to First Officer Panahian regarding the aircraft's track.
Around 11:20 a.m, the crew's request for descent to the airport was granted by air traffic controller. They were then cleared for a VOR/DME approach to the airport and then were cleared for landing at runway 12. Captain Hosseini asked First Officer Panahian to set the altitude to , a bit lower than the airport's minimum descent altitude of . First Officer Panahian then tried to position the aircraft for the final approach. The aircraft was flying with its autopilot on and was slightly higher than the normal approach profile. It was still not configured for landing as the flaps were still at 0 and the aircraft was faster than the usual speed for approach.
The aircraft rapidly approached the minimum descent altitude for Sharjah. The crew managed to decrease the airspeed by a bit and deployed the flaps to 10. Captain Hosseini later set the flaps to 25. The landing gear began to be extended. The aircraft, however, was still too high and too fast. With a remaining distance of less than between the aircraft and the airport, Captain Hosseini tried to take over the control from First Officer Panahian. He intended to give the control back to Panahian once the aircraft was on the correct approach profile. First Officer Panahian accepted Hosseini's request and gave the control to him.
Crash.
Keen to decrease their altitude, Captain Hosseini tried to cause the thrust setting to enter the ground range by pulling the thrust lever's ground range selector. Immediately afterwards, the propeller speed jumped and caused a noisy sound loud enough to startle both pilots. The aircraft pitched down and gradually rolled to the left at an angle of more than 30 degree. Captain Hosseini exclaimed "Why!" and eventually realised that the reverser had been deployed in mid-air. Shortly after, he instructed First Officer Panahian to move the lever fully forward. They successfully decreased the roll and raised the nose, but not enough to keep the aircraft from falling.
Another aircraft on the ground was on its way to line up with the runway when the crew saw Flight 7170 pitching down and starting to roll again. It entered a steep left bank dive and went into a spiral. The aircraft continued to plunge in a heavy left bank angle until it struck the ground, narrowly missing a residential area, crossed a road and exploded on impact, bursting into flames. It crashed about from the end of the runway. The front portion was destroyed, but the main fuselage was still intact.
A nearby witness was the first to arrive at the crash site. According to him, cries for help could still be heard from inside the aircraft. He tried to open one of the doors but failed as the door was already crushed by the impact forces. While some parts of the fuselage wall had been broken during the crash, fires prevented the passengers from escaping. As there were no fire fighting vehicles for several minutes, the fire rapidly spread and quickly engulfed the fuselage. Just 10 minutes after the crash, the whole cabin section was already engulfed in flames. Rescue services eventually arrived at the scene approximately 25 minutes after the accident, but by then it was already too late as the aircraft had been completely destroyed by the fire.
The rescue operation was further hampered by rubbernecking, where local residents had crowded the scene of the crash. The fire was extinguished about 30 minutes after the accident. At least 4 survivors were found within the crash site, but one succumbed to their injuries as they were being transported to hospital. One of the survivors was found in stable condition, while the other two were unconscious and were in critical condition.
A total of 43 people perished in the accident. Bodies of the victims were lined up and were taken to Dubai for identification.
Passengers and crew.
There were 40 passengers on board, including one infant. Most of the passengers were migrant workers. Many on board were going to renew their work visas, as the permit regulations in UAE at the time required workers to renew their visas outside the country. The flight was frequented by migrant workers from UAE who were intending to renew their visas in the Iranian resort island of Kish as Kish Island was designated by Iranian authorities as a free trade zone and no visa was required prior to arrival. The tickets were also cheap and the island was also a popular tourist destination with abundant affordable accommodation.
Reports indicated that there were people of at least 12 nationalities, in which the majority were Iranians.
Officials stated that the three survivors of the crash consisted of one Egyptian, one Filipino and one Iranian. The Filipino survivor was found to be conscious and stable, while the other two were in serious condition. The survivors were reportedly seated in the middle section of the aircraft.
There were 6 crew members on board, consisting of 2 cockpit crew, 2 cabin crew and 2 security personnel. The commander of the flight was 48-year-old Captain Ahmed Hosseini. He had a total flying experience of 6,440 hours, of which more than 1,500 hours were on the Fokker 50. He was a former military pilot. The co-pilot was 50-year-old First Officer Nemat Panahian. He had accumulated a total flying experience of nearly 4,000 hours, of which 517 hours were on the Fokker 50.
Investigation.
The investigation was conducted by Emirates General Civil Aviation Authority, as well as several investigation team from the outside, including the Iran Civil Aviation Organization (CAO), representing as the State of Operator and the Dutch Transport Safety Board, representing as the manufacturer of the aircraft.
Based on the aircraft's logbook, there were no recorded defects or unscheduled maintenance since overhaul. The aircraft technical logbooks indicated that there had been no scheduled or unscheduled maintenance conducted on the aircraft propeller components.
The Cockpit Voice Recorder and the Digital Flight Data Recorder were retrieved from the relatively undamaged tail section of the aircraft in very good condition. They were presented to the Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA) in Le Bourget, France on 16 February 2004 for extraction of the DFDR data and CVR transcription.
Conduct of approach.
The approach was initially planned to be conducted by Captain Hosseini as the pilot flying, but it ended up being switched during the enroute phase. The sudden role switch caught First Officer Panahian off guard as it had not been agreed by both pilots prior to the flight. First Officer Panahian had refused on conducting the approach as he was not confident on his ability to land, but Captain Hosseini pushed him and insisted him to do it. Either for cultural or professional reasons, Panahian eventually accepted this, albeit reluctantly.
Due to the unprepared nature of the approach, Panahian caused the aircraft to fly at an altitude that was too high for an approach and an airspeed that was faster than the normal airspeed value of . The aircraft was not configured appropriately for the landing. The flaps and the landing gear were eventually deployed while the aircraft was flying at about . Dissatisfied with their current approach profile, Captain Hosseini eventually took over the control from Panahian, adding that he would delegate the controls back to Panahian once they had stabilised the aircraft for the intended approach profile.
As the aircraft became nearer to the airport, the crew had to quickly decrease their altitude, or they would have overshot the runway. Captain Hosseini tried to do this by attempting to cause the engine thrust to enter the ground range by pulling the ground range selector. The thrust, however, moved even further from the ground range and entered the reverse value. The reverse setting was prohibited to be deployed while the aircraft was still in mid-air. As the engine started to produce reverse thrust, massive drag forces began to appear, crippling the aircraft's ability to fly.
As the crew realized that the reverser had been deployed in the air, the thrust levers were quickly moved forward. Their action on moving the throttle, however, was too quick, giving the hydraulics no time to compensate. The counterweights eventually caused the blade pitch of the left propeller to fully decrease. Instead of increasing the airspeed, the engines put the propellers into maximum reverse, producing large amount of drag. The aircraft then dived with a heavy left bank angle and crashed onto the residential area.
Reverse angle.
The thrust range in Fokker F50 was consisted of two control ranges. The first one was the flight control range, which was used for virtually nearly all phases of flight other than landing. The other was the ground range, which also included the reverse range. Both thrust ranges were typically used during landing due to its deceleration effect. As both were used for landing, pilots were generally banned from applying this thrust setting while their aircraft was still in mid-air as the resultant drag forces would have threatened the controllability of the aircraft.
To prevent the