Air services between the mainland and Barra have been cancelled after one of the aircraft was damaged by a de-icing vehicle at Glasgow Airport.
The second plane used has also been out of action because it has been undergoing a routine overhaul.
Loganair said because Barra's runway is a beach it has been unable to source a replacement aircraft at short notice.
Passengers have been flying to Benbecula and making a two hour journey by road and ferry to reach Barra.
Loganair said the Twin Otter planes were the only aircraft capable of landing on Barra's beach runway.
A company spokesman said: "We recognise that such disruption will be extremely unwelcome for its customers at any time of year, but especially so in days prior to Christmas.
"Loganair wishes to offer its most sincere apologies to those customers whose journeys will be affected by this situation."
Comhairle nan Eilean Siar transportation committee chairman, Donald Manford, said the Barra-Glasgow was a lifeline service for the Western Isles.