What happened
On 20 October 1998, a Slingsboy T67C Firefly, registration G-BOXK, was returning to its base at Woodford following a series of performance-based spinning exercises. The flight, conducted as part of a training programme, was operated by a flight school. After successfully completing the planned manoeuvres in the vicinity of Gamston, the aircraft began its return journey, descending to altitudes significantly lower than usual.
As the aircraft approached the area of Mow Cop, Staffordshire, it was observed by several witnesses flying at a very low altitude. Some observers noted the aircraft performing manoeuvres near a local school, while others described the aircraft flying straight and level at approximately 300 feet. Near the site of the accident, witnesses observed the aircraft performing a sudden, rapid movement described by some as a loop or a flick. The aircraft subsequently impacted the south-facing slope of a ridge, which was parted by an upward 20-degree gradient. The impact was followed by an intense post-impact fire that destroyed the aircraft. Both the instructor and the student pilot sustained fatal injuries.
The investigation
The investigation examined the aircraft's flight path using radar and radio transmissions, which confirmed the aircraft had been flying at altitudes as low as 100 to 500 feet above the terrain during its final approach. Examination of the wreckage revealed that the engine was operating under power at the time of impact and that the flight controls were intact, with no evidence of mechanical failure or pre-impact malfunctions. The cockpit controls indicated the throttle was set to nearly full power.
Investigators also reviewed the school's operations manual, which prohibited flying below 1,000 feet above ground level unless specifically authorised. While the instructor had the authority to permit such low-level flight, no written authorisation for this specific deviation was recorded. Additionally, the investigation considered the impact of local weather, noting that a strengthening south-westerly wind could have introduced turbulence in the area.
Findings
- The aircraft was flying at a much lower altitude than the 1,000-foot minimum specified in the school's operations manual.
- The aircraft's final manoeuvre was consistent with a flick roll, likely induced by aggressive pitch control inputs.
- There were no mechanical or system failures identified that contributed to the crash.
- The flight path took the aircraft directly towards rising ground at a low altitude.