But after repeatedly opening and closing the latches, flight controllers managed to lock the wing and Discovery was cleared to dock.

BBC: Discovery docks with space station

When rolled into position inside an aircraft, containers lock into place to avoid moving about in flight.

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The replacement fish are being driven up from part of the Kennet and Avon Canal, while lock repairs are being carried out on the Bath Flight.

BBC: Fire-hit Erewash canal set to be restocked with fish

Without a crew, however, the antennae would quickly lose lock with Mission Control, and the ISS computers would not receive commands from the flight controllers.

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