Passengers are asked to check in earlier today, 30 July.
Guernsey Electricity says that a high voltage power fault cut supply to many properties in the Forest parish at around 5pm yesterday, 29 July.
As a result, Guernsey Airport's hold baggage screening system was taken offline.
It meant there was no twilight check in availability for Aurigny passengers.
This morning, 30th July, passengers with hold baggage are asked to check in earlier and to expect queues.
A spokesman for Guernsey Airport says there is a contingency for this situation, which it has put in place, so that hold baggage can be security screened, pre flight, but this will take longer than usual.
Guernsey Electricity says its engineers took around four hours to fix the fault.

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