Serious Injury During Aircraft Maintenance

The Royal Canadian Air Force (RCAF) have reported on an serious injury that occurred during maintenance of an Airbus A310 (known as a CC-150 Polaris).

RCAF A310 CC-150 Polaris at Trenton (Credit: RCAF)

RCAF A310 CC-150 Polaris at Trenton (Credit: RCAF)

The RCAF have 5 CC-150 Polaris aircraft at 8 Wing at CFB Trenton, Ontario.  During maintenance at Trenton:

A contractor technician was lockwiring the drainplug of the left no. 4 flap screwjack gearbox while another technician, who was concurrently working on the right main landing gear brake system, applied hydraulic power to the aircraft.

When the hydraulic system was activated, the left no. 6 wing spoiler closed onto the lockwiring technician, seriously injuring him.

RCAF A310 CC-150 Polaris  Spoiler System (Credit: RCAF)

RCAF A310 CC-150 Polaris Spoiler System (Credit: RCAF)

The preliminary investigation revealed deficiencies in aircraft maintenance safety procedures and equipment.

These concerns were immediately brought to the attention of both the RCAF technical authority and the contracted air maintenance organization, which undertook numerous rectifying and prevent actions to ensure this accident would not reoccur.

The investigation then focussed on supervision and organizational factors that preceded the accident.

The investigators identified “numerous organizational safety stressors” including:

  • contract, facilities, organization and personnel disruptions;
  • training and supervision of apprentices with too few supervisors; and
  • a mismatch between contractor resources and operational demands which cumulatively increased the safety risk being incurred to meet these demands.

Additionally, the investigation determined that the contracting and accreditation mechanisms were insufficient to detect this situation and reliance on the contractor to self-identify the risk could create a potential conflict of interest within an incentivized performance contract.

This highlights a safety assurance gap for contracted maintenance that should be addressed by the RCAF.

RCAF A310 CC-150 Polaris (Credit: RCAF)

UPDATE 15 March 2017: Inflite Engineering Services were fined £160,000 in court after an incident at Stansted Airport on 10 June 2015.  Two workers were injured when the mobile elevated work platforms they were using were knocked over when another employee closed the wrong circuit breaker, inadvertently operating the air brake.

The Health and Safety Executive (HSE) commented:

Aircraft maintenance companies are reminded that not all risks are covered by the Aircraft Maintenance Manual and additional measures need to be introduced.

The HSE investigation found: ” no suitable risk assessment was in place and there was a lack of effective monitoring.”

UPDATE 6 July 2017: We discuss one possible solution to occurrences such as this in Deliberate Action: A Mindful Method from the Nuclear Navy


Aerossurance is pleased to be supporting the annual Chartered Institute of Ergonomics & Human Factors’ (CIEHFHuman Factors in Aviation Safety Conference for the third year running.  This year the conference takes place 13 to 14 November 2017 at the Hilton London Gatwick Airport, UK with the theme: How do we improve human performance in today’s aviation business?ciehf 2017

Aerossurance has extensive air safety, maintenance, human factors and safety analysis experience.  For aviation advice you can trust, contact us at: enquiries@aerossurance.com