The preliminary report on the accident involving a Marathon Airlines Embraer E195 aircraft operating on behalf of Air Serbia on flight JU324 on Sunday February 18 has concluded that “one of the most probable causes of the accident was the inadequate assessment of the take-off parameters during the preflight preparation of the crew and after the decision to take-off with a shorter runway length compared to the initially planned one”, following interviews with the key parties involved. A full investigation, which will likely take up to three months, but can last up to twelve months, is now under way. The preliminary report compiled by the Center for Investigation of Accidents in Transport of the Republic of Serbia (CINS) also found there were no technical issues with the aircraft or engines.
The preliminary report also includes the full correspondence between Air Traffic Control (ATC) and the pilots, which is not fully audible in the recordings which have been published online. It further shows the crew on the flightdeck of JU324 were warned numerous times they were departing from the wrong intersection which was not assigned to them. During pre-flight preparations, the crew planned to take-off from the position on the runway at intersection D6, for which, the pilots stated, they performed a “double check of the calculation of the take-off parameters”. They received clearance from ATC to taxi to intersection D6, which they confirmed. The crew then reported to ATC they were approaching the D6 intersection, to which they received a response to prepare for take-off from D6, exit and line up on the runway. Then came the message from a second air traffic controller if the crew was aware they exited the D5 intersection instead of D6. The preliminary report states the controller then told the crew the take-off run available (TORA) was 1.273 meters. The crew asked ATC for a minute to make checks. According to the statement of the crew, they then calculated the parameters for take-off using a hand-held flight computer in the form of a hand-held tablet of the co-pilot. During this time, the controller informs the crew to perform the calculations and also report if they want to backtrack down the runway to position D6. Thirty seconds later, the crew announced they were able to take off from D5 . ATC then asked again whether they were able to take-off, to which the crew immediately confirmed, after which they received final approval to take-off.
The preliminary report states the plane took-off leaving behind a cloud of dust and climbing slowly. It damaged the approach lights of Belgrade Airport’s runway 12R, while the monitoring antenna of the ILS system hit the left wing.
According to the statements given, the crew estimated the plane had normal acceleration upon take-off. The flight crew made changes in the thrust of the engine in order to get as high a speed as possible. At eighty knots, the crew stated that everything was fine, while at 100 knots, they noticed there was inadequate runway length. Considering the available length of the runway, and the speed at which the plane was accelerating, the crew decided it was safer to continue taking off because they estimated the plane would become airborne. According to the crew, the plane then started to shake and they felt the impact of an unknown object. After the E195 took off, the crew then heard an unknown noise from the left side and noted the lights on the left wing had stopped working. The crew then began to receive information about problems with a number of systems, the most significant of which were the flaps and non-functioning of the engine’s Bleed Air Systems. They then proceeded to go through the appropriate emergency checklists .
The crew eventually performed a low pass over the runway for ground staff to determine if the landing gear was extended. During that time, they reported increased vibrations and problems with the flaps. They decided to land at a higher speed due to problems with the flaps, however, as they noted, within the prescribed limits. Apart from the occurrence of vibrations, they did not have any other problems during landing.
After touching down, ATC instructed them to park at gate C2 after they were informed by the crew they had no issues with the aircraft. After pulling into the gate, ground staff noticed that fuel was leaking from the left wing of the Embraer and told the crew to quickly shut down the engine and all other systems. The full investigation will determine as to why the crew was instructed to proceed to the gate at Terminal 2 with an aircraft in such a state.
The pilot of the aircraft was a 58-year-old Italian national who had type-ratings on the A320 and Embraer 170 family while the co-pilot was Polish with E170 type-rating. The crew had previously operated a return flight to Vienna, after which they were to operate the Dusseldorf service.
