A Ryanair flight to Ibiza was delayed at Stansted for 90 minutes after an airport worker crashed a set of steps into the plane.
The aircraft was taken out of service as a precaution after the wing was inspected, according to the BBC.
The incident happened as baggage handlers and ground staff members of the GMB and Unite unions employed by Swissport are on strike at the airport over the Diamond Jubilee weekend.
Swissport said the incident did not involve anyone brought into cover, but that a "local worker" was involved.
Union members said the strike occurred as new rosters threaten pay cuts and could mean working extra days for free.
The strike will end at 5.30 BST on Wednesday.
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