The man on board the Brixham-based scalloper Danielle became trapped by a rope and sustained arm and chest injuries on 6 June 2006 off Falmouth.

The Marine Accident Investigation Branch said it took 30 minutes longer to rescue him than it could have.

Rescue services said they were acting on the report's recommendations.

Arm amputated

The Danielle was about 17 miles (27km) off Falmouth when the deckhand got caught in a winch rope. He ruptured a lung and nearly severed his arm. The arm was later amputated.

He was evacuated from the vessel by lifeboat in an operation involving coastguards and ambulance crews. He arrived at the Royal Cornwall Hospital two hours and 40 minutes after the trawler captain's first emergency call.

Marine Accident Investigation Branch (MAIB) investigators said there were avoidable delays.

They found that ambulance control staff did not obtain full medical details and therefore did not prioritise their initial ambulance response. That led to one ambulance being diverted to a higher priority call, resulting in a delay before another one arrived.

As well as this, Falmouth Coastguards were not aware that the lifeboat with a medical adviser on board was deployed at 20.5 knots rather than 25, a faster speed reserved for life-threatening cases.

Arm amputated

The MAIB called for all rescue services to know exactly how each other operates, and what their rescue policies are.

It admitted that the delay would have made little difference to the casualty, but said there should be closer cooperation.

The RNLI has told the coastguard about its use of different cruising speeds.

The Maritime and Coastguard Agency said it was looking at how decisions were made about evacuating casualties.