The team at RNLI Lerwick rushed to the aid of a 26-metre trawler in the early hours of Saturday morning.
They received a call from the British-registered trawler at around 2.30am.
The boat was around eight nautical miles east of Dunrossness and had a fouled propeller.
There were seven members of crew onboard the vessel.
A lifeboat was launched from Lerwick which reached the trawler at around 3.15am.
It was decided that the boat should be towed back to shore, where it arrived at Victoria Pier at around 6.30am.
Harbour pilot vessel The Knab was there to assist in the operation.
“Did the right thing”
Tommy Goudie, deputy second coxswain, said the team aboard the vessel were right to call for the coastguard when they realised their propeller was fouled.
He said: “The trawler skipper did the right thing by contacting the coastguard when he realised that his propeller was fouled and he had no propulsion.
“Our volunteer crew responded quickly to the request to launch in the early hours of morning. We were pleased to be able to help vessel reached a safe harbour for repairs.”
Luckily, the seas were calm for the rescue, with only light winds.