The Air Accident Investigation Unit (AAIU) of Belgium’s Service public f�d�ral Mobilit� et Transports have released their final report concluding, that the accident was caused by the decision to reject the takeoff 12 knots after passing V1 speed. Contributing factors were: - Engine Nr 3 experienced a bird strike, causing it to stall. This phenomenon was accompanied by a loud bang, noticed by the crew. - The aircraft line up at the B1 intersection although the take-off parameters were computed with the full length of the runway. - The situational awareness of the crew, - Less than maximum use of deceleration devices. - Although the RESA conforms to the minimum ICAO requirement, it does not conform to the ICAO recommendation for length. The crew had briefed a departure from runway 20. The crew determined, that they needed the full length of the runway for takeoff. The briefing included procedures to reject takeoff before V1 as well as rejecting takeoff after V1 if the airplane was unable to fly. The decision speed V1 was computed at 138 KIAS and the speed to rotate at 157 KIAS. After a normal pre-flight check and departure preparation the airplane taxied towards runway 20 at the B1 intersection leaving 312 meters (1023 feet) less available distance for takeoff than the full length (2987 meters/9797 feet). The airplane was cleared to takeoff from B1 intersection. The crew was not aware, that they were not using the full length of the runway and their takeoff distance had been reduced by 312 meters and thought, they’d still have their takeoff margin of 300 meters. A few seconds after reaching V1 (138 KIAS) engine #3 (inner right, JT9D-7Q) ingested a bird. 5 seconds after V1 the engine stalled and produced a loud bang as well as a vibration noticed by the crew. The captain felt, that the airplane was no longer accelerating and decided to reject takeoff about 2 seconds later (7 seconds after V1). The thrust levers were brought to idle and braking action was initiated, the thrust reversers were not deployed. The first officer called tower they were going into the overrun. The captain turned the airplane a few degrees to the right to avoid the approach lights. The airplane left the runway at a speed of 72 knots, went over a first embankment, dropped 4 meters (13 feet), broke into three parts and stopped just above the railway embankment. The crew exited through the L1 door. The report states, that the crew received minor injuries, the airplane was totally destroyed. The bird ingested was identified to be a European Kestrel (”Falco Tinnunculus”, see picture at the top). Its organic remains were recovered from each stage of the low pressure compressor, fan blades, bleed valve linkage support and sound absorbing segments of engine #3. Engine #4 was inspected as well though to a lesser extent, after two fan blades showed indications of organic debris. Sound analysis of the cockpit voice recorder showed, that engine #3 was recovering following the bird strike until the moment, when the captain closed the throttle levers. The flight data recorder recorded the engine parameters only every 4 seconds. The flight data recorder stored an EPR value of about 0.1 less than the other engines for engine #3 just prior to the onset of the braking action. The engine stalled at about mid length of the runway at a point, where the downslope of the runway increased from 0.62% to 0.93%. This might have contributed to the impression of the crew, that the airplane did no longer accelerate. N704CK had experienced 27 engine related incidents since January 2004, well above average of the Kalitta fleet. Engine #3 had been replaced one month before the accident after a fire warning. Engine #4 had been recently replaced without an incident related reason. The captain had experienced an engine failure associated with a loud bang during takeoff from Incheon Airport (Seoul, South Korea) a few years earlier, which was a genuine engine failure. The captain was aware of 12 engine related incidents during takeoffs in the entire Kalitta fleet since 2004, 4 of them on N704CK. The bang heard in Brussels was as loud, if not louder, than the one the crew heard in Incheon, giving the impression that the event may be worse than the event in Incheon. Each of the engine related incidents on N704CK happened with a different engine, the high rate of incidents seems coincidental. The inflight shut down rate of the JT9D engines in the Kalitta fleet is higher than the world average, mostly due to Kalitta policy of precautionary shut downs. The Runway End Safety Area (RESA) is required to extend for 90 meters past the runway end at a width of 90 meters according to ICAO regulations. The actual RESA of runway 20 complies with that regulation, however does not fulfill the recommendation of the same regulation to extend the RESA to 240 meters in length. Had runway 20 been equipped with an Engineered Material Arrestor System (EMAS), a specifically designed surface to stop airplanes during an overrun, and had N704CK not turned right, the airplane would have been stopped before the first ditch using an EMAS, computations by the accident investigators showed.

Overview of runway and overrun area :

Track of aircraft:

According to the draft a bird (kestrel) has been found in engine #3. The thrust of the engine was therefore reduced by about 40 percent. The bird was ingested about 4 seconds after V1 had been exceeded.

The report concludes, that the takeoff could and should have been continued as the airplane was already above V1.

Due to the poor reputation of the engine (the first series of the engine did have problems) and the commander’s experience with engine problems 15 days earlier the commander decided to reject the takeoff, however, the crew did not deploy thrust reversers.

The report also mentions, that the crew was not sufficiently concentrated during the takeoff and especially after the decision to abort takeoff.

The full accident investigation report has not yet been published.

The report could not be verified by The Aviation Herald, no such recent incident is known – the article sounds like the news of May 25th needed three months to reach Interfax.

The Google Translation of the original Russian Article reads:

August 12, 2008 20:26

Brussels. August 12. INTERFAX.RU – In Brussels airport serious incident occurred – transport plane during take-off to drive out beyond the runway and collapsed into two parts, on Tuesday reported a representative aeroporta.Po him, four out of five people on board crashed plane victim , Received minor injuries.

Although aircraft fuel tanks were full, he did not fire. The reason for the disaster has not yet been determined.

Reportedly, the victim aircraft – Boeing-747 “in the cargo version – belonged to the American freight company” Kalitta “and sent to Bahrain.

According to the data derived from the FDR, the airplane initially accelerated normally down runway 20 under a constant acceleration until a momentary loss of power by one engine, which was accompanied by an explosion witnessed both by the crew and air traffic controllers at the tower of Brussels. The loss of power and bang occured at around V1 speed (maximum speed, at which decision to reject takeoff can be safely taken).

Two seconds after the bang all four engines were brought to idle and the airplane decelerated “vigorously”, the slow down continuing until the final position 300 meters past the runway end. According to FDR thrust reversers were not used in the deceleration.

All four engines were inspected. All engines were running at the time of full stop, no catastrophic damage had occured to either of the engines, no casings were punctured, all 4 engines remained attached to the wings. The outer engines (#1 and #4) turn freely, whereas the inner engines (#2 and #3) are blocked. All thrust reversers were found in the stowed position.

Especially engines #3 and #4, the right hand engines, were inspected with an endoscope, though very incomplete at this stage. The inspections however failed to reveal any damage, all compressor and turbine blades are in position and show no damage in both low pressure and high pressure compressors and turbines. The engines will be torn down in an appropriate workshop for further examination at the table under the presence of the Belgian AAIU.

The examination of the airframe and structures did not reveal any catastrophic damage prior to the final impact, when the airplane fell about 4 meters before coming to full stop just before the railway tracks. The airframe broke up in three parts upon that impact.

The cargo pallets did not move significantly. The cargo will be weighed to determine exact takeoff and stopping distance.

The investation team is also interviewing first responders like fire fighters and policemen. The Belgian AAIU expects, that the investigation will last 6 to 12 months before a final report will become available.

The airport reopened the runway by June 13th, however initially without ILS. Several antennas of the instrument landing system for runway 20 as well as approach lighting for runway 02 have been destroyed by the impact of the Kalitta Boeing 747, the repairs are estimated to take eight to twelve weeks including calibration.

The fuel has been pumped off the airplane on Tuesday, the site has been declared safe Wednesday.

No damage on the surface of the runway was found, possible damages to runway and approach lightings as well as the ILS are yet to be evaluated. The runway is thought to be reopened within 5 to 8 days.

The chief of Belgocontrol, responsible for Air Traffic Control at Brussels Airport, said, that one of the controllers on duty saw a flame out of a starboard (right hand) engine. The observation was immediately relayed to the crew and the fire brigades activated at the same time.

A Kalitta Airways B747-200, registration N704CK performing freight flight K4-207 from Brussels to Bahrain with 5 crew, overran runway 20 at Brussels Zaventem Airport while rejecting takeoff. The fuselage broke up in three parts, but no fire erupted. 4 minor injuries are being reported.

A witness (”plane spotter”) reported to have heard some “slight knock” while the airplane attempted takeoff, then saw the plane coming towards him and started to run for cover.

Runways 02/20 and 07R/25L were closed. The railway lines to and from the airport were shut down as a precaution as the airplane came to rest close, but before the railway lines with fuel spilling. Fire brigades stopped the fuel spillage in the meantime. As of Monday morning (May 26th) the train traffic is gradually resuming. Runway 07R/25L has been reopened while runway 02/20 is still closed.

The Belgian TV reported in their Sunday evening news edition, that the airplane carried diplomatic cargo including a diplomatic car plus additional cargo, described by Belgian Authorities as not dangerous for environment or people. The airplane carried 77 tons of cargo, about half of which was the diplomatic cargo. Police has been deployed to protect the airplane and cargo.

DHL have confirmed, that they had leased the airplane to carry DHL cargo from Brussels to Bahrain. A spokeswoman for DHL said, that they are not sure whether items to be delivered, which include post, will be affected.

The National Transportation Safety Board of the USA (NTSB), led by NTSB investigator Joe Sedor, is going to join the Belgian Government for the investigation. The NTSB reports in the press release, that a loud bang was reported during the takeoff, continuing, that there were 4 people on board of the airplane with no injuries being reported.

Post Impact Video available at: http://www.deredactie.be/cm/de.redactie/mediatheek/1.311709