Caspian Airlines Flight 7908 was a scheduled commercial flight from Tehran, Iran, to Yerevan, Armenia, that crashed near the village of Jannatabad, outside the city of Qazvin in north-western Iran, on 15 July 2009. All 153 passengers and 15 crew members on board died.

The subsequent crash investigation found that the incident had been caused by fatigue failure and consequent disintegration of a rotor disc in the left hand engine (engine No. 1). Fragments of the disc severed two of the three hydraulic control systems and damaged fuel lines for the center engine (engine No. 2). Fuel leaking from these damaged lines ignited, causing a large fire. The engine failure also severed the control rods on the tail of the plane, resulting in the pilots losing control of the aircraft.

Aircraft The aircraft was a Tupolev Tu-154M built in 1987 and operated by Iran's Caspian Airlines. The aircraft had registration EP-CPG, an aircraft which entered service on 20 April 1987 as YA-TAR for Bakhtar Afghan Airlines and was sold to Ariana Afghan Airlines in 1988. YA-TAR served with Ariana Afghan until sold to Caspian Airlines on 15 March 1998, 11 years after it was built. It was re-registered as EP-CPG in 1999.

At the time of the accident, the aircraft had accumulated 27,510 flight hours and 16,813 cycles. Its last major overhaul had been performed on 18 March 2005. Following the overhaul, it had completed 9,888 hours and 6,581 cycles up to one day before the accident. The aircraft was checked for safety in June 2009 and was given a flight license until 2010. According to an Armenian aviation official, the plane had gone through technical controls in Mineralnye Vody Airport in southern Russia in June.

Engine history The aircraft was equipped with three Soloviev D-30KU-154-II twin-shaft, low-bypass turbofan engines. The engines were configured in the standard Tu-154M arrangement: engine no.1 on a pylon on the left rear of the fuselage, engine no.3 on a pylon on the right rear, and engine no.2 mounted in the tail.

No. 1 engine was manufactured in 1992 and had been used for a total of 17,726 flight hours and 9,117 cycles. It was installed on the aircraft in September 2008. Its last overhaul was conducted in November 2007. According to official calculations, the engine had been used for 3,911 hours and 1,843 cycles since its last overhaul. Engine no. 2 was manufactured in 1993 and had accumulated a total of 16,060 flight hours and had undergone a total of 6,669 cycles. It was last overhauled in February 2008. No. 3 engine was considerably the youngest, as it was manufactured in 1994 and had a total of 9,507 flight hours and a total of 3,718 flight cycles. It was overhauled in September 2008, the latest among the other two.

Passengers and crew Passengers NationalityTotalIran157Armenia5Georgia2Canada2Australia2Total168

The aircraft was carrying 168 people on board, consisted of 153 passengers and 15 crew members. Officials stated that majority of those on board were Iranians, however the exact number were not announced. Reports stated that there were 40 Armenians on board. Iranian state-news agency FARS stated that there were 47 Armenians on board, without specifying the exact number of Armenian citizens. The Government of Armenia later confirmed that while there were at least 40 ethnic Armenians, only five of them were Armenian citizens, consisting of three passengers and two crew members. The remainder were Armenians of Iranian citizenship.

The Georgian embassy in Yerevan confirmed that two of its staff were on board. Canadian authorities confirmed that two Canadians who held dual nationality were on the flight. Meanwhile, the Australian government stated that at least two Iranians with dual Iranian-Australian nationality were on board the aircraft. Beside the listed foreigners, the deputy chairman of Armenia's civil aviation authority, Arsen Pogosian, stated that the rest were Iranian citizens.

Among the passengers were Levon Davidian, a former member of Iranian parliament and a prominent figure for the Armenians in Iran, and Iranian composer , who was going to a concert held by Ebi in Yerevan. Also on board were 10 members of Iran's national junior judo team, consisting of eight athletes and two coaches. The team was heading to a training camp in Yerevan in preparation for the upcoming judo competition in Budapest, Hungary.

Crew There were discrepancies regarding the official number of the crew. The Iranian government-owned news agency FARS and Armenian press stated that there were 15 crew members, with the following being listed as the cockpit crew members:

Captain Ali Asghar Shir Akbari (53), who was also acting as the instructor pilot during the flight. He had accumulated 10,700 total flight hours. He was type-rated on the Fokker F-28 and Tupolev Tu-154M and had passed his most recent simulator check on 26 June 2009. In Flight 7908, Akbari was originally not supposed to be on the flight; however, he was called in as a substitute for another instructor pilot. Pilot Mahdi Firouse Souheil (55), who was the pilot flying and was under supervision of Akbari. He had accrued a total flying experience of 6,700 total flight hours. Graduated from a piloting college in the United States in 1976, he was type-rated on the Boeing 707 and Tupolev Tu-154M. His license recorded that he had completed 240 of his required 250 supervised flight hours, meaning he had only 10 hours of supervised flight remaining before he could be released to unsupervised captain duties. He was seated on the left side during the flight. First Officer Javad Masoumi Hesari (33), who was acting as the pilot non-flying and co-pilot for Souheil, seated on the right side. He had a total of 1,850 total flight hours, but only 250 of those were on the Tupolev Tu-154M. Flight Engineer Nima Salehie Rezve (28), who had a total of 320 flight engineer hours.

The Armenian government stated that there were also two flight engineers from Armenia, identified as Gregory Barseghyan and Suren Soghomonyan. The Russian embassy in Iran stated that preliminary reports indicated that there were no Russians on board the flight. The final investigation report stated that there was a Russian-speaking flight engineer in the cockpit, whose voice was recorded by the aircraft's CVR. The identity of the crew, however, was not disclosed in detail, nor could it be confirmed that the person was of Russian nationality.

Accident Flight history

Flight 7908 was an international scheduled passenger flight from Imam Khomeini International Airport in Tehran to Zvartnots International Airport in the Armenian capital of Yerevan. The flight was a regularly scheduled flight and was frequented by Iranian Armenians; many were visiting relatives in Armenia. The flight was supposed to take about 1 hour and 20 minutes with a cruise altitude of at . On 15 July 2009, the aircraft was boarded with 158 passengers and 10 crew members, piloted by Mahdi Firouse Souheil as the pilot flying and his co-pilot Javad Masoumi Hesari. Souheil was supervised by an instructor pilot, Captain Ali Asghar Shir Akbari, who was seated on the back.

The aircraft had been delayed for 1 hour and 30 minutes due to poor pre-flight preparation. At 11:39 a.m, the aircraft took off from Tehran's Runway 11 and climbed. The autopilot was then engaged and the aircraft proceeded to climb to before starting its turn towards its first waypoint "PAROT". Flight 7908 was then handed off to Tehran's area control center and was eventually told to proceed to an altitude of 34,000 feet.

00:34:09 Tehran Approach "CPN7908, Contact control 119.3" 00:34:09 First Officer Hesari "Contact 119.3 CPN7908, have a nice day" 00:34:19 First Officer Hesari "Tehran radar, CPN7908 squawk 1523" 00:34:26 Tehran ACC "CPN7908 good morning, radar contact climb FL340" 00:34:33 First Officer Hesari "Climbing 340, CPN7908" 00:34:36 Unidentified crew Don't get tired! 00:34:38 First Officer Hesari Same to you, Sir.

This was the last transmission from Flight 7908 to Tehran ATC. At 11:51 a.m, approximately 16 minutes into the flight, the aircraft reached its cruising altitude. Pilot Soheil could be heard in the recording saying "Take it, take it", meaning that he was giving the flight control duties to First Officer Hesari, which was responded with "I have it". After a while, he ordered the crew to gather information regarding the flight parameters and other data.

11:51:37Pilot SoheilTake it, take it.11:51:42First Officer HesariI have it.11:51:51Pilot SoheilOk, gather information. Accident At 11:52 a.m, at , the aircraft was on a cruise climb when a thump was heard from behind the aircraft, with a sound consistent of an object impacting the aircraft that could be heard in the cockpit recording. The aircraft suddenly tilted to the left, however the crew didn't react to it. Few seconds later, the parameters for engine No.1 suddenly became abnormal. The rotor speed of the low pressure compressor had increased from 84% to 99.3%. Few seconds later, the rotor speed jumped to 120%, and the fuel flow of the engine dropped fast. A loud bang was then heard from the rear fuselage, shaking the aircraft and causing it to roll slightly to the left. Then, it started losing altitude.

11:52:12 Unidentified crew Он может гореть! (It's catching fire!) 11:52:15 First Officer Hesari This [person] says to shut [the engine] down 11:52:19 Pilot Soheil Shut it down 11:52:22 First Officer Hesari Shut it down, sir

Meanwhile, the aircraft continued to turn to the left, reaching an angle of 64°. The pilots tried to counteract it by making a right bank input through the rudder pedal; however, the aircraft didn't budge. The aircraft kept banking at such an angle, and the pilots pressed the pedals even harder. Their attempts seemed to have no effect. Even after fully applying the pedals, the aircraft kept turning towards the left. As it was in a nose-down attitude, the aircraft kept losing its height and started to gain more speed.

Soheil desperately tried to turn the aircraft to the right, saying "Turn! Turn!" while struggling. Realizing the gravity of the situation, First Officer Hesari asked Soheil on whether he should declare an emergency, to which Soheil responded firmly "no". Seconds later, the "engine fire" alarm blared. The Russian-speaking crew informed the rest that the engine was on fire. The pilots were still preoccupied with the control of the aircraft as it kept diving towards the ground.

11:52:47 Pilot Soheil Turn! Turn! 11:52:52 First Officer Hesari Should I declare [emergency], Captain? 11:52:53 Pilot Soheil No 11:52:59 Unidentified crew Звуковой сигнал! (engine fire signal!)

While the aircraft plummeted towards the ground, Tehran ATC suddenly sent a transmission for a routine check-in on the flight. Taking his own initiative, flight engineer Rezve, without authorization from the pilots, quickly said, "Mayday, Mayday, Mayday, engine failure!" This message, however, didn't reach the ATC for an unknown reason. The ATC worker remained unaware of the situation on board the flight. As the ground drew nearer and the aircraft undoubtedly could not be controlled, First Officer Hesari said, "Oh no!". This would be the last words recorded from the cockpit.

11:53:03 Tehran ACC CPN7908, Tehran 11:53:19 Flight Engineer Rezve Mayday Mayday Mayday! Engine failure! 11:53:24 First Officer Hesari Oh no! 11:53:26 Tehran ACC CPN7908, do you read? Commmentary End of recording