Emergency rescue work on the Cutty Sark is already under way, but its long-term success will hinge on the extent of the damage to the clipper’s wrought-iron hull. In the aftermath of the blaze on Monday the immediate concern was whether it had buckled irreparably in the 1,000C (1,832F) heat. Structural engineers will report in a month on the damage to the sleekly curved hull, which expanded and then contracted in the fire.

Dr Eric Kentley, the curatorial consultant to the Cutty Sark Trust, says: “If one or two of the iron frames that make up the hull have been distorted then we are OK. If the ship has twisted then it changes the restoration project quite considerably. In the very worst case we will be able to give her the appearance that she has always had because the masts, the rigging and much else are safe. What may be compromised is her shape under the water line. We might have to investigate techniques to repair wrought iron, which might be a nightmare.”

Richard Doughty, the chief executive of the trust, is more optimistic. “A cursory inspection shows there isn’t any devastating damage,” he says. “It’s serious but it’s not the end of the Cutty Sark. We are already working to repair the ship.”

If the damage proves to be slight, the fire may even provide a boost to the restoration programme, which has been under way for six months but had been struggling to raise the funds required, estimated at £25 million before the fire and up to £35 million now.

Simon Beams, the architect behind the restoration, says: “Either she is completely devastated because the iron has become too brittle, or the heat may have stripped the paint – which we would have had to do anyway – retarded the degradation of the salt and actually strengthened the iron.”