Air Traffic Control at Birmingham International Airport notified this serious incident to the Air Accidents Investigation Branch (AAIB) at 1240 hrs on 23 February 2006. The following Inspectors participated in the investigation:
Mr R J Tydeman Investigator in Charge
Mr P Hannant Operations
Mr S J Hawkins Engineering
Mr M W Ford Flight Recorders
The aircraft was on a scheduled flight from Tehran, Iran, to Birmingham International Airport in the United Kingdom (UK). Following an uneventful flight, the aircraft was radar vectored for a Localiser/DME approach to Runway 33. The aircraft commenced a descent from 2,000 ft to the published minimum descent altitude of 740 ft whilst still 11 nm from the runway threshold. At a point 6 nm from the runway the aircraft had descended to an altitude of 660 ft, which was 164 ft agl. The radar controller noted this descent profile and, through the tower controller, issued an immediate climb instruction. However, the crew had already commenced a missed approach, which they initiated when they received a GPWS alert. The aircraft was radar vectored for a second approach during which the flight crew again initiated an early descent. On this occasion, the radar controller instructed the crew to maintain their altitude and the crew successfully completed the approach. The aircraft landed safely from the second approach.
The investigation identified the following contributory factors:
The primary cause of the incident was the use by the crew of the incorrect DME for the approach at Birmingham International Airport.
There was also a substantial breakdown in CRM, which was partly due to the presence of a third flight crew member on the flight deck. He was not present during the approach briefing nor when the navigation information displayed was selected. He attempted to support the crew in their efforts to fly the approach but inadvertently re-enforced the commander’s misinterpretation of the DME indications. This occurred despite the first officer initially recognising the discrepancy between the distance to the threshold and the distance displayed on the VOR/DME, and attempting to communicate this to the other members of the flight crew.
Three Safety Recommendations have been made.
Download full report:
7-2007 F-OJHI.pdf (2,713.57 kb)