The alarm was raised at around 2.20am when a chemical tanker and a cargo ship collided around 30 miles north-west of Guernsey.
RAF Search and Rescue teams and coastguards joined their French counterparts in successfully airlifting 22 crew members of both vessels to safety.
The crews abandoned their boats after the incident and donned lifejackets as they waited for assistance.
Flight Sergeant Tim Dickinson, of the RAF Aeronautical Rescue Co-ordination Centre based at RAF Kinloss, said all crew members were rescued by helicopter and lifeboats.
It is understood they have been taken to hospital in Guernsey.
He told the BBC: "It was a textbook rescue operation but we were very fortunate because the sea conditions were benign.
"The rescue helicopter picked up 12 casualties while the lifeboat attended to the other 10.
"As far am I aware no-one has been seriously injured."
It is understood that the chemical tanker was carrying phosphoric acid, which has sparked pollution fears.Reuse content