What happened
On 1 February 1998, a Jodel D140B, registration G-AROW, was performing a private flight departing from Runway 08R at Redhill Aerodrome. Shortly after the aircraft became airborne, personnel at the Control Tower observed that the left-hand baggage hatch had opened. The tower staff alerted the pilot and suggested an immediate return to land on the reciprocal runway, 26L.
As wind conditions were calm, the pilot performed a 180-degree teardrop turn and successfully landed the aircraft. No handling difficulties were reported during the landing. The detached hatch was subsequently located in a field near the airfield. The incident resulted in damage to the aircraft, specifically a split in the upper fuselage skin behind the cockpit and the tearing of the hatch from the airframe, though there were no injuries to the pilot.
The investigation
Investigators examined the mechanism of the baggage hatch to determine why it had failed. Although the pilot had confirmed the key-lock was in the 'locked-closed' position during his pre-flight checks, a physical inspection revealed a mechanical discrepancy. While the locking bolt had been moved into position, the bolt ends had not actually engaged with the sleeve plates attached to the fuselage upper longeron.
Findings
- The primary cause of the incident was that the locking bolt failed to properly engage the sleeve plates despite the key-lock being in the locked position.
- The hatch design lacks dowel pins to ensure the precise alignment of the locking pin with the holes in the sleeve plates.
- Consequently, the hatch can appear securely locked when the key is turned, even if the bolt is not correctly seated in the receiving plates.