An injured fisherman was airlifted from his vessel during the early hours of Tuesday morning.
The Sumburgh-based rescue helicopter was summoned after an initial call at 4am.
The vessel, which has not been named by Shetland Coastguard, was 150 miles north east of Unst when the incident happened.
The crewman was taken to the emergency landing site at Clickimin.
Shetland Coastguard say the helicopter arrived at the emergency landing site at 8.30am, following a refueling operation on a rig.