Back in calmer water or harbour, the fouling still has not cleared itself. Someone is considering going up the mast in a bosun's chair to free it. What must be checked first?

A. The boat should be in calm, sheltered conditions with the engine off or in neutral and secured, a properly rated bosun's chair and halyard used (checked for wear), a second independent line as a safety backup, and someone competent tending the line and watching at all times

B. No safety backup or second line is ever needed when going aloft

C. It is fine to go aloft in any sea state as long as the person is enthusiastic about trying

D. Anyone can be sent up on any available rope regardless of its condition or rating

A. A jam like this is always caused by the sail being the wrong size for the boat

B. The halyard has almost certainly wrapped around something at the masthead — a spreader, the VHF aerial, the wind instrument, or twisted itself — and is now fouled, which is a common cause of a sudden jam partway up a hoist

C. This pattern means the wind has suddenly become too strong to hoist any sail at all

D. This always means the mast itself is about to fail structurally

A. Wrap the halyard around a winch and crank it tight regardless of the jam

B. Cut the halyard immediately without trying anything else first

C. Pull as hard as possible with extra crew to try to force the sail the rest of the way up

D. Stop pulling immediately and ease the tension off — continuing to haul or sheet in hard risks damaging the halyard, the masthead fitting, or pulling something loose up the mast that could then fall