Two landing gear pins that were not removed from a Qantas aircraft resulted in the inability to retract landing gear after takeoff, an investigation by the Australian Transport Safety Bureau (ATSB) has revealed.
The incident, which took place on 21 June, involved a Boeing 787-9, registered VH-ZNH, bound for Perth from Sydney.
After taking off, the flight crew received a warning signal indicating that the main landing gear had not retracted, even after they toggled the gear lever to ‘up’.
“Despite consulting the aircraft’s electronic checklist, the flight crew were unable to resolve the retraction issue,” states the ATSB.
The crew elected to return to Sydney, where the aircraft, which was carrying 106 passengers and 13 crew, landed safety.
A post-landing inspection revealed that two downlock pins in the main landing gear had not been removed after the jet was towed to the gate before the flight. A 787 has five landing gear pin locations — one in the nose gear, and two on each side of the main landing gear.
“In addition, subsequent preflight inspections by the flight and dispatch crew did not identify that the pins remained in place prior to departure,” says ATSB transport safety director Stuart Macleod.
The ‘Remove Before Flight’ streamers attached to the two pins were also missed, with the ATSB noting it could have been stuck on the landing gear, “from a combination of grime and the recent wet and windy conditions”.
This prompted the bureau to call for awareness of where the ‘Remove Before Flight’ streamers are, especially given “varying environmental conditions that can reduce their visibility”.
“‘Remove before flight’ streamers are visual reminders to remove covers and lockout devices prior to flight, but can be subject to varying environmental conditions that can reduce their visibility,” says Macleod.
“Expectation can also affect your ability to identify these warning devices. If you are not expecting to see a ‘remove before flight’ streamer, you are significantly less likely to detect one that is present. The same principle can also prevent the discovery of damaged and/or missing components,” he adds.
The ATSB also notes that two members of the tow crew which removed the gear pins had never towed a 787 prior to the occurrence. Other Qantas aircraft, such as the Airbus A330 and 737, have only three landing gear pin locations — one in the nose gear, and one in each of the main landing gear.
“Moreover, once removed, on the A330 and 737 the gear pins are stored on the flight deck, whereas on the 787 they are stored in the aircraft’s electrical equipment centre, just aft of the nose gear,” states the ATSB.
Since the incident, Qantas has worked on storing the 787 gear pins in the flight deck after removal, “to bring them in line with other aircraft in its fleet, and to enable ease of access to verify pin stowage”.
The carrier has also highlighted to engineering, ramp and flight staff on the number of gear pins on the 787, as well as their locations.
Cirium fleets data shows that the aircraft was delivered to Qantas in November 2018 and was briefly parked in March and June 2020.