Accident Overview
On 30 August 2008, a Beech 1900D aircraft operating as flight TWD8300 crashed in a dense wooded area near Bushi Village, Nigeria. The aircraft was destroyed by impact and fire. The wreckage was located by hunters later that day. Three occupants were fatally injured.
Flight Details
The aircraft departed Murtala Muhammed Airport (MMA) Lagos at 0736 hrs for a positioning flight to Bebi airstrip, Obudu, under Instrument Flight Rules (IFR). The filed route was LAG – UA609 – POTGO – DCT – ENU – DCT - OBUDU, but the actual flown route was LAG – UA609 – POTGO – LIPAR – LUNDO – IKROP – BUDU. The aircraft climbed to FL250 and was transferred to Port Harcourt at 0845 hrs. The crew requested descent, cleared to FL110, then further descent to FL050 by Enugu. The aircraft deviated from the flight plan, flying on airway UA609 direct to IKROP from POTGO.
Final Moments
During the approach, the crew input coordinates into the GPS that gave different distances to Bebi. They agreed on a coordinate and then focused on visually locating the airstrip. The Ground Proximity Warning System (GPWS) activated with "Terrain, terrain… pull up" warnings multiple times, but neither pilot responded. The aircraft struck terrain at approximately 0920:15 hrs at an altitude of about 3,400 ft. The flight duration was 103.75 minutes. At 0923 hrs, the Bebi radio operator called the aircraft without reply, and later contacted Calabar, which also had no contact.
Probable Cause
The official investigation determined the probable cause: "The flight crew conducted an approach into a VFR airfield in an instrument meteorological condition and did not maintain terrain clearance and minimum safe altitude which led to Controlled Flight Into Terrain. The crew did not respond promptly to GPWS warning." Contributory factors included crew unfamiliarity with the route, ATC failure to detect route deviations, improper change from IFR to VFR, failure to use approved Jeppesen charts, and Lagos ACC not questioning waypoint discrepancies.