The most common and most likely answer to this crossword clue is the 13 letter word SQUARE-RIGGED
I've seen this crossword clue in The Guardian
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Buddy explains!
The straight part
We know that "needing particular set of sheets" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case needing particular set of sheets = square-rigged.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SQUARE-RIGGED mean?
SQUARE-RIGGED adjective- (of a ship) Having (approximately) square sails rigged onto spars perpendicular to the keel.
- Smartly dressed.