On 18 June 2021, a British Airways 787 being loaded for a cargo-only flight at London’s Heathrow Airport suffered an unintended nose gear retraction. This week, the UK AAIB issued a special bulletin detailing what went wrong and warning 787 operators to remain vigilant when performing ground maintenance operations.

What happened to G-ZBJB?

The British Airways Boeing 787-8 (MSN 38610) was being prepared for a cargo-only flight from London to Frankfurt. During cargo loading, engineers were performing maintenance actions to clear messages in the aircraft’s systems. One of the required actions included performing a cycle of the landing gear with hydraulic power applied to the aircraft. To prevent the landing gear from retracting pins are inserted into the main and nose gear downlocks.

UK AAIB photo of British Airways 787 G-ZBJB’s nose gear retraction
British Airways 787 G-ZBJB after suffering a nose gear collapse in London. Photo courtesy UK AAIB

In this instance, the pin that should have been inserted into the nose gear downlock was actually inserted into the nose gear apex pin bore, which is right next to the correct downlock hole.

Image showing correct and incorrect positions of downlock pin
Figure from the UK AAIB special bulletin showing the correct and incorrect insertion of the NLG downlock pin.

Fixing the problem

After a similar incident in 2018, Boeing issued a service bulletin requiring the installation of a cover over the apex bore hole to prevent the insertion of the pin in the wrong hole. The US FAA then issued an airworthiness directive in 2020 mandating the installation of the covers within 36 months. British Airways had not yet completed the installation of the covers, but it has since said it will expedite the process on its 787s.

The UK AAIB investigation continues and a final report is forthcoming.