Inspectors from the Department of Transport's Marine Accident Investigation Branch will carry out an inquiry.
Fifty people were hurt as the 307 passengers abandoned her in a heavy swell. Last night 30 were in Jersey General Hospital, many suffering from broken legs and ankles.
The drama began at 10am, about 15 minutes after the French-owned St Malo, which operates between the port of that name and the Channel Islands, left St Helier. The ferry was holed as it passed Corbiere point off south- west Jersey.
As water poured into one of the aluminium hulls, the ferry began to list and the captain sent a mayday signal. Some of the passengers - 185 Germans, 40 French and the rest presumed British - stepped on to a flotilla of rescue boats, others were winched into helicopters and more than 100 leapt into life-rafts amid waves up to 4ft high.
Frederic Avierinos, chairman of Channiland, the St Malo's owners, last night confirmed that the craft had struck a rock but said the cause was unknown.
However, Dave Turner, watching from the shore, said the ferry was too close to rocks. "I saw her come around the back of the lighthouse, which they use as a short cut on the high tide."
Last night the St Malo, built two years ago, was beached in St Aubin's Bay, south Jersey, where divers will examine her.
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