Thai Airways Flight 311Friday July 31, 1992
After experiencing difficulty in deploying the flaps while approaching Katmandu, the landing was aborted. The ATC did not have radar service. After some confusing exchanges between the tower and the aircraft, the crew headed north instead of south to begin its second approach. The aircraft flew into a near vertical mountain wall at 240 knots. In the final seconds, the captain assessed the Ground Proximity Warning System warning as false. The accident was caused by a combination of occurrences, errors and actions by both the crew and ATC. The initial problem with the flaps, the lack of radar service, a misread chart by the captain causing him to turn the plane in the wrong direction and the use of non-standard phraseology among other items led to the accident.