AAIB Report Highlights Brake Seizure Incident on Beech 400A at Newquay Airport

Image Credit:AAIB

In a detailed investigation report released by the Air Accidents Investigation Branch (AAIB), a serious incident involving a Beech 400A aircraft, registered as N709EL, at Newquay Airport in Cornwall on 7 October 2023, has been brought to light.

The report elucidates the sequence of events that led to the aircraft’s brakes seizing and its mainwheel tyres deflating during landing, underscoring potential safety improvements.

Unusual Deceleration Upon Touchdown

The incident unfolded immediately after the aircraft made touchdown at Newquay Airport. The flight crew experienced an unexpected deceleration surpassing normal parameters. In response, reverse thrust and speed brakes were promptly deployed. However, as the aircraft’s speed diminished below approximately 50 knots, it began drifting towards the runway’s right edge.

A skilful combination of weathercocking—pivoting into the wind—and the application of left pedal manoeuvres enabled the crew to steer the aircraft back to the centreline of the runway. The Beech 400A eventually came to a halt, albeit angled about 45 degrees to the left of the runway’s centreline, with its mainwheel tyres deflated and brakes seized.

Cause of the Incident

The AAIB’s investigation pinpointed the immediate cause of the rapid deceleration upon touchdown. It was determined that this could be attributed to either the tyres having deflated due to the melting of fuse plugs, brake seizure, or a combination of both factors. Notably, it was discovered that the incident’s root cause lay in the inadvertent heating of the brakes during the takeoff run, attributed to the parking brake being left engaged with partial pressure.

A contributing factor to the occurrence was identified as the lack of adequate warning systems. Specifically, the aircraft was found to lack a light or caption signalling that the parking brake was engaged, as well as missing an auditory or visual alert for when the parking brake remained on upon the application of takeoff power. Additionally, the absence of a ‘release parking brake’ item on the ‘Before Takeoff’ checklist was highlighted as a significant oversight.

Safety Recommendations and Conclusion

In light of the findings, the AAIB has issued a safety recommendation to the aircraft manufacturer concerning the incorporation of a ‘release parking brake’ item in the ‘Before Takeoff’ checklist. This recommendation aims at enhancing the safety protocols and ensuring such incidents can be averted in the future.

This incident serves as a reminder of the importance of rigorous pre-flight checks and the need for comprehensive safety features on aircraft to prevent similar occurrences. The AAIB’s thorough investigation and subsequent recommendations underscore the commitment to aviation safety and the continuous improvement of safety protocols in the aviation industry.

View the full report here.