What happened
On 1 August 2004, a Boeing A75N1 Stearman, registration G-BAVO, was performing a private flight from Old Bucken andham Airfield in Norfolk. After completing all necessary pre-flight inspections, the pilot initiated a takeoff from the grass runway. While the initial acceleration and power levels appeared normal, the aircraft failed to achieve a satisfactory climb after becoming airborne.
As the aircraft struggled to gain altitude, the pilot attempted an emergency landing in a nearby field. This field was covered in dry straw and featured furrows running across the aircraft's flight path. Upon impact with the uneven ground, the aircraft lost its undercarriage and flipped onto its back. The impact caused severe damage, including a broken undercarriage, damage to the engine frame, and a fire that spread to the upper wing and forward fuselage. The pilot and one passenger managed to exit the aircraft without assistance before the fire was extinguished by emergency responders.
The investigation
The investigation examined the flight conditions, the aircraft's performance, and witness observations. Witnesses noted that the aircraft lifted off in a three-point attitude and appeared to be flying near a stall, with the wings dropping repeatedly. Despite the engine sounding as though it was at full power, the aircraft could not maintain altitude and descended from approximately 100 feet.
The investigators also considered environmental factors, such as the potential for reflected heat from the dry straw to affect air density or the presence of thermal activity. While a local gliding club confirmed the day was thermic, the investigation looked at whether a sudden, slight tailwind caused by thermal movement might have contributed to the takeoff performance.
Findings
- The aircraft was operating below its maximum takeoff weight.
- The aircraft entered a high-drag takeoff attitude that prevented it from gaining sufficient altitude.
- The uneven, furrowed surface of the landing field caused the aircraft to nose over and sustain structural damage and fire.