Relative docked when heading to plane to prepare for takeoff (7)
I believe the answer is:
unclasp
'plane to prepare for takeoff' is the definition.
I can't judge whether this defines the answer.
'relative docked when heading to' is the wordplay.
'relative' becomes 'uncle' (uncle is a kind of relative).
'docked' means to remove the last letter (to dock can mean to remove the tail of an animal).
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'heading to' becomes 'p' (I can't explain this - if you can you should give a lot more credence to this answer).
'uncle' with its final letter taken off is 'uncl'.
'uncl'+'as'+'p'='UNCLASP'
Can you help me to learn more?
(Other definitions for unclasp that I've seen before include "let go" , "Loosen grip on" , "Open - release from grip" , "Detach (necklace, belt, etc)" , "Unfasten" .)