Perdida de Potencia
Por lo que estuve leyendo en diversos foros, Pprune/Airliners.net/Flight International, al parecer de el Flight Data Recorder y del Voice Data Recorder ya sacaron la informacion y habria un reporte preliminar.
Se dice que tuvieron una "perdida de empuje" en uno de los motores seguido de un fuerte "bang". Este hecho sucedio justo o muy cercano a la V1.
A su vez el Torrero, a mi parecer cometio un gran error, les informo que veia fuego del motor.
Pasada la V1, 2 segundos despues de recibido el aviso de la TWR, abortan el despegue con el resultado consiguiente.
Se aplico reversa en dos motores, usualmente por procedimiento en mi empresa solo se accionan reversas SIMETRICAMENTE.
La carga fue encontrada correctamente estivada y en su lugar.
Calculos de Pista fueron correctamente introducidos en el FMC del avion.
No se encontro ningun danio catastrofico en el motor que tuvo la reduccion de potencia, este se ve en que no se encontraron partes daniadas ni el capot del mismo agujereado.
Aca les copio el informe de Flight International,
From Flight International magazine's web-site.
Overrun Kalitta 747 suffered power loss but no engine damage
By David Kaminski-Morrow
Investigators in Brussels have found no evidence of engine damage on the Kalitta Air Boeing 747-200 freighter destroyed in a take-off overrun on 25 May, but confirm that one engine suffered a loss of power at a critical speed threshold.
The Belgian inquiry has also determined that the correct aircraft parameters, runway selection and weather data were uploaded to the 747’s computer before departure, and that use of runway 20 would not have posed any problems.
Two pilots, two engineers and a passenger accompanying diplomatic cargo escaped after the jet broke into three sections during the overrun. There was no prior structural failure; the break-up was caused by impact forces as the jet went over a 4m (13ft) drop.
“At this stage there is no reason to make urgent recommendations,” says the Service Public Federal Mobilite et Transports, which is heading the probe.
Analysis of the flight recorders, it says, shows the initial part of the take-off roll was normal, with constant acceleration until one of the Pratt & Whitney JT9D engines suffered a “momentary” loss of power.
This power loss, which was accompanied by a “detonation”, occurred as the aircraft reached the V1 speed – the threshold beyond which a crew normally must commit to becoming airborne, because the aircraft cannot be stopped safely on the runway.
The crew heard the noise and air traffic controllers witnessed flames from the right side of the aircraft.
Two seconds later the engine thrust was reduced to idle and the aircraft decelerated, but failed to stop before the runway end. Thrust reversers were not deployed, although a rejected take-off calculation does not take reverser use into account.
All four engines were operating as the 747 overran and, upon inspection, showed no sign of catastrophic failure. The engine cowlings were not punctured.
Following the indications of a possible problem with one of the right-hand engines, these were subjected to an initial endoscopic inspection of the high-pressure turbine and compressor.
“This inspection, although incomplete, failed to reveal any internal damage,” say the investigators. The fan-blades and low-pressure turbine remained in place and were similarly undamaged.
Specialists are to carry out a more thorough teardown and examination of the engine components.
None of the cargo pallets had shifted significantly during the accident, but the investigators are to check the loading distribution as part of the inquiry. The jet had stopped over in Brussels as part of a service between New York JFK and Bahrain.
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Preliminary report of the Air Accidents Investigation Unit of the Belgian Federal Ministery of Transport at:
in Dutch
http://www.mobilit.fgov.be/data/pbs/p080604an.pdf
in French:
http://www.mobilit.fgov.be/data/pbs/p080604af.pdf
- no apparent problem as regards the use of RW 20/02 for this flight - all flight data correctly entered in flight computer
- brief loss of power on one engine at about (sic) V1 associated with loud bang and flames, as confirmed by crew cq witnesses/controller.
- 2 sec after the bang, thrust was reduced to idle - no reverse thrust commanded - vigourous braking started and maintained until final stop
- preliminary on site endoscopic inspection of engines 3 and 4 - although very incomplete - didn t show any damange in the HP or LP compressor, HP turbine nor of the fan blades
- cargo found correctly stowed after impact - actual cargo on board being compared with load sheet data
- no catastrophic structural damage before final impact (4m drop)
- L1 door blocked due to structural damage on impact, 'service' door used to evacuate
FDR and CVR will now be analysed further , and engines will be recovered from the wreckage and further investigated upon.
