History of the Flight
On 17 August 2003, a private pilot flying a Europa, registration G-IGII, conducted an air test approximately 10 miles north of Nottingham Airport. The pre-flight checks, takeoff, departure, and climb to 3,000 feet were uneventful. After slowing below the published manoeuvring speed, the pilot completed 45-degree banked turns through 360 degrees. A loud bang was heard, and air rushed into the cockpit. The pilot realized the port door was open, the perspex was broken, and much of it was missing. He managed to close the door. Descending to 1,500 feet, he transmitted a distress call to Nottingham Airport but was able to fly a normal visual approach and landing to Runway 09.
Door Closure
The Europa door is hinged at the top and opens upwards, with a gas-strut at its rear edge to restrain the door when open. Past problems had occurred when doors twisted slightly during rapid closure, causing the forward latch to engage while the aft latch rested against the fuselage skin. The pilot was convinced the door was secure before takeoff, having experience with similar top-hinged doors and being aware of the need to check both latches. An associate who watched the aircraft taxi out believed she would have noticed incorrect closure. Another associate noted that the interior trim obstructed a clear view of the latches, suggesting it could contribute to failing to detect a latch not correctly engaged.
Bonding of the Transparencies
The damaged door was examined by the kit manufacturer. The remaining transparency appeared securely bonded and proved difficult to remove. The bond line where the transparency was missing was identical in appearance to the attached areas, indicating consistent and adequate bond strength. The door was supplied without the transparency, which was bonded by the builder using a specified adhesive. The pilot and an associate with composite manufacturing experience expressed concerns about the adhesive material and the bonding process applied to G-IGII.
Airflow Through the Cockpit
The manufacturer's Technical Manager reported conversations with the pilot about the hinged fuel selector access flap on the central tunnel. The pilot noted he had to rest his elbow on the flap to keep it shut. The Technical Manager recalled that when the aircraft was flown with doors off, the access flap lifted due to a pressure difference. He suggested that air flowing from the cockpit during the flight could indicate the rear latch was not engaged, allowing the door to flex and creating a gap. This could cause airflow into the cockpit via the access flap and potentially lead to forward latch disengagement and door opening. However, after repair, the pilot noted some airflow still emanated from the flap area.
Summary
The door structure's stiffness would not permit gross deflection under normal aerodynamic loads if both latches were engaged. Any deflection would be insufficient for latches to disengage, even if bond separation occurred at the forward edge of the transparency. Disengagement of one or both latches would be required for the door to open in flight without occupant operation.