https://web.archive.org/web/20000305...s/740422-0.htm
An accident report worth re-visiting. In 1974 a PANAM Boeing 707 was en-route Hong Kong to Bali at night. There was no DME or ATC radar at Bali in those days. The crew of the 707 planned on an NDB instrument approach on arrival. Forecast was fine but it was a black moonless night for arrival.
Approximately 30 miles north of Bali one of the two ADF's on the 707 swung and the crew misinterpreted this as an indication that the aircraft was overhead the real Bali NDB. They commenced the instrument approach as per the NDB chart. The aircraft crashed into a mountain.
Today blessed with highly accurate GPS position fixing this type of accident would be unlikely. But there are airports around SE Asia and in Australia still with an NDB as the let down aid. The PANAM 707 crash 43 years ago should remind pilots that ADF false overheads can still remain a trap to an unwary crew.