Sign of gratitude after aircraft takes one into curious view of the sky (11)
I believe the answer is:
planetarium
'view of the sky' is the definition.
'sign of gratitude after aircraft takes one into' is the wordplay.
'sign of gratitude' becomes 'ta' ('ta' can mean thanks).
'after' says to put letters next to each other.
'aircraft' becomes 'plane' (plane is a kind of aircraft).
'takes' is a charade indicator (letters next to each other).
'one into' becomes 'rium' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ta' after 'plane' is 'planeta'.
'planeta'+'rium'='PLANETARIUM'
'curious' acts as a link.
This may not be correct. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for planetarium that I've seen before include "one offering vision of heaven" , "Star-filled building" , "Dome where the heavens are projected" , "Astral display" , "Where the night sky is projected onto a ceiling" .)