What happened
On 29 November 2004, a DHC-8-311 Dash 8, registration G-JEDE, was performing a scheduled passenger flight from the Isle of Man to London City Airport. The flight involved 32 passengers and 3 crew members. During the final stages of the 5.5-degree precision approach to Runway 10, the first officer handed control of the aircraft to the commander at the decision height of 430 feet.
Upon taking control, the commander significantly reduced engine power to decrease the aircraft's speed. As the aircraft entered the flare, the pilot reported a heavy sink rate. In an attempt to arrest the descent, the pilot applied a large nose-up elevator deflection. This rapid increase in pitch, combined with insufficient engine torque, caused the rear of the aircraft to strike the runway. The impact abraded the tail-scrape detector and caused minor damage to the fuselage skin. No injuries were reported among the passengers or crew.
The investigation
The AAIB examined the aircraft's flight data recorder (FDR) and cockpit voice recorder (CVR) to reconstruct the approach. The data revealed that at the time of control handover, the aircraft was traveling 12 knots faster than company procedures required. The investigation established that the commander reduced engine torque to an unusually low level, reaching as low as 2% on one engine, which destabilized the approach.
While the pilot attempted to increase power ten seconds before the strike, the engines did not reach the torque levels typically seen during standard London City landings. The investigation also noted that the aircraft's airspeed had dropped to VREF at the moment of impact. The crew's report of potential turbulence from nearby buildings was considered unlikely given the low wind speeds recorded at the time.
Findings
- The primary cause of the tail strike was the unusually low engine power setting maintained during the final stages of the approach.
- The reduction in power, combined with the need to decelerate, left the aircraft with insufficient energy to manage the descent rate.
- A rapid and large nose-up pitch input was required to compensate for the sink rate, directly resulting in the tail hitting the runway.
- The approach was unstable, as the aircraft was flying faster than specified in company standard operating procedures at the point of handover.