Black plane? (3)

I believe the answer is:

jet

I believe this clue is a double definition.

'black' is the first definition.
(jet black is a kind of black)

'plane?' is the second definition.
(jet plane)

(Other definitions for jet that I've seen before include "Hard black mineral used as gem" , "Narrow spouting stream" , "Black; spurt" , "Black gemstone" , "Glossy black colour" .)

I've seen this clue in the Evening Standard, The Telegraph and The Times.

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