The ones that flew? (4)

I believe the answer is:

aces

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'the ones' is the definition.
('ace' can be a synonym of 'one')

I can't explain the rest of the clue.

(Other definitions for aces that I've seen before include "Two will make deuce" , "never come back" , "wartime pilots?" , "passes with flying colours in US" , "They're high and low on cards" .)

I've seen this clue in the Evening Standard.

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