20_SIA Accident

1. The aircraft attempted to take off under typhoon conditions

    Wind speed of 144 kph(~78knots), visibility of below 500-600 metres, at night. This                            would make keeping on the center line of the runway difficult, and the visibility meant that it       would be difficult to see the lights of the runway.

1. It was taking off from a runway that had been closed for repair. The runway was thus occupied by construction machines, being obstacles for the accelerating plane.
2. The intended runway was near the runway under repair and the two had almost the same identification numbers. The disused strip was not blocked off because it was used for taxiing aircraft. This would create much confusion as the pilots would not be sure if it was the correct runway, which may also be deadly under normal circumstances if the runway was also used by another aircraft.
3. The control tower was not equipped with ground radar and, due to the poor visibility, could not see if the aircraft was on the correct runway. Thus did not allow the control tower to warn them if they were on the wrong runway.
4. The pilots were also under pressure from their airline to avoid costly delays. This may gave influenced the pilot's decision to continue the flight.

Opinion:

I think that the pilots shoulder some responsibility for the accident, but part of the blame also goes to the airport staff. If the flight crew had been provided with the correct information about the weather, the flight would have been cancelled. The control tower staff should really have warned the pilots about the disused runway because of its close proximity to the intended one, and if the correct runway was used the plane would have taken off safely, as this particular crash was caused by it hitting the concrete blocks and construction equipment. Since other carriers cancelled their flights, it can be taken that it was the pilot's decision to continue, since the airport authorities did not intervene. 

Note: Yes, it is possible to take a 747-400 off the ground under these conditions(Tried in X-plane 9 Demo.) You might want to get an airsick bag ready though, and be thankful you weren't flying an landing into the airport.