What happened
On 1 November 2009, a DHC-8-402 Dash 8, registration G-ECOZ, was performing a commercial passenger flight from Newcastle to London Gatwick. During the approach to Runway 08R, the crew encountered significant turbulence and airspeed fluctuations, likely due to windshear. At approximately 40 ft altitude, the commander reduced power to 8% torque in response to a speed increase. Although the pilot subsequently initiated a flare to increase the pitch to 7.5°, this maneuver failed to arrest the aircraft's rate of descent. Consequently, the aircraft experienced a heavy touchdown, resulting in the tail striking the runway.
Following the event, the 'touched runway' caution light illuminated. The crew followed emergency procedures, which involved contacting engineering after parking the aircraft. There were no fatalities and no injuries to the 42 passengers or 4 crew members on board. The impact caused significant damage to the aircraft's lower skin and fuselage frames, as well as damage to the runway surface.
The investigation
The AAIB investigation examined flight data recorder (FDR) and cockpit voice recorder (CVR) information, alongside meteorological data. Investigators found that the aircraft's descent rate was not sufficiently arrested during the flare. The investigation also reviewed the operator's standard operating procedures (SOPs) regarding flap selection and pitch monitoring. It was noted that the aircraft was using Flap 15, a setting that provides less pitch maneuver margin during landing compared to Flap 35. Additionally, the investigation looked into the effectiveness of the operator's 'Pitch 6' warning call and the manufacturer's guidance on power management.
Findings
- The primary cause of the tailstrike was the failure to arrest the rate of descent during the landing flare.
- A reduction in power to 8% torque at 40 ft altitude led to a loss of lift, which the subsequent flare could not compensate for.
- Windshear-induced turbulence caused significant airspeed variations during the final stages of the approach.
- The use of Flap 15 configuration limited the available pitch margin to counter the increasing sink rate.
- The crew's reliance on pitch adjustments rather than power management to control the descent rate contributed to the heavy landing.
Safety action
- The operator intends to update the 'Touched Runway' emergency checklist to include an instruction to advise Air Traffic Control (ATC) of the event.
- A safety recommendation was made for Bombardier Aerospace to modify the DHC 8-Q-400 Aeroplane Operating Manual to include an instruction to advise ATC in the 'Touched Runway' emergency checklist.