What happened
On 24 March 2009, a BN2A Mk.III-2 Trislander, registration G-RLON, was performing a commercial passenger flight departing from Runway 27 at Jersey Airport. As the aircraft rotated for take-off, the pilot observed the nose baggage bay door open warning light illuminate. The commander elected to continue the take-off sequence, but at an altitude of approximately 200 feet, the nose baggage bay door physically separated from the aircraft.
Following the separation, the pilot initiated a turnback procedure. While the aircraft was over the sea, the detached door struck the left windscreen, causing scratches, and subsequently impacted the left propeller spinner, causing a dent, before finally striking a propeller blade and its de-ice boot. The pilot successfully executed a 'teardrop' approach and landed the aircraft safely on Runway 04. There were no injuries to the single crew member or the 15 passengers on board.
The investigation
The investigation focused on the mechanism of the door's separation. Because the door and its latching hardware fell into the sea, physical evidence from the components themselves was unavailable. However, the operator's initial internal review suggested the door was likely correctly latched prior to departure.
An inspection of the operator's remaining six aircraft revealed that the door hinges remained attached to the airframe, but the complete door assembly—including the handle mechanism and shoot bolts—had detached. A detailed visual examination of these components showed movement between the eccentric lock and the lever assembly. Specifically, the square drive on the lever showed signs of 'rounding off,' which led to the loosening of the lock nut and the eventual detachment of the handle.
Findings
- The forward baggage bay door separated from the BN2A Mk.III-2 Trislander during the initial climb phase.
- The separation caused the door to strike the aircraft's windscreen, propeller spinner, and propeller blades.
- Wear in the latching mechanism caused the lock nut to loosen, leading to the detachment of the handle and the subsequent failure of the door to remain secured.