Incident Overview
On 1 August 1999 at 1107 hours UTC, a Piper PA-22-150 (registration G-ARAX) was conducting a local private flight from Old Sarum Airfield, Wiltshire. The aircraft, manufactured in 1956 and powered by a Lycoming O-320-A2B piston engine, was descending in a tight turn from 3,000 feet when the pilot leveled off at 2,500 feet in turbulence. At that moment, the windscreen suddenly shattered.
Immediate Actions
The pilot responded by pulling back on the control yoke to reduce airspeed. The passenger, reacting instinctively, assisted with the yoke movement. The pilot then flew the aircraft back to Old Sarum Airfield and executed a normal landing without further incident.
Pilot and Aircraft Details
The pilot, aged 52, held a Private Pilot's Licence with Instrument Meteorological Conditions (IMC) and Night Ratings. His total flying experience was 900 hours, with 700 hours on the Piper PA-22-150 type. In the preceding 90 days he had flown 50 hours, and in the last 28 days, 10 hours.
Post-Incident Findings
The pilot theorized that the windscreen failure may have resulted from unusual stress on the airframe caused by the tight turn combined with turbulence. The maintenance organization responsible for the aircraft examined the airframe and found no permanent deformation. By reassembling the shattered windscreen fragments, they determined that no foreign object had struck the windscreen. During the aircraft's most recent Annual Inspection, a small crack in the windscreen had been repaired using a 'stop-drill' method in accordance with accepted practice. However, the investigation reportedly established that the windscreen failure did not originate from that repair.
Conclusion
The aircraft sustained a shattered windscreen but no other damage. Both occupants were uninjured. The incident was reported via the Aircraft Accident Report Form submitted by the pilot.