Restoring Chay Blyth's penultimate vessel (5)
I believe the answer is:
yacht
'vessel' is the definition.
(I know that yacht is a type of vessel)
'restoring chay blyth's penultimate' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'chay' is 'yach' which is within the answer.
A single letter 't' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for yacht that I've seen before include "Pleasure craft" , "Sailing craft" , "Type of boat" , "Sailing or motor vessel for cruising or racing" , "Luxury purchase" .)