The most common and most likely answer to this crossword clue is the 7 letter word EJECTOR
I've seen this crossword clue in The Daily Telegraph
E
J
E
C
T
O
R
More clues leading to the result EJECTOR
- I retired in Provence, lacking aspiration to play the bully and bouncer
- Sort of seat for a high-flyer
- Opening to escape canopy top in plane, alternatively
- Sort of safe seat high-flier appreciates in difficulty
- Justice for Liberal voter, gaining seat
- Caught in plane in European theatre? Use this!
- One who discards throws out head bouncer
- Pumping device to remove bits of orange residue
- It sends out core jet's slurry
- Jet engineered with core safety mechanism for use before a crash
Buddy explains!

The straight part
We know that "Sort of safe seat high-flier appreciates in difficulty" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sort of safe seat high-flier appreciates in difficulty = ejector.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 EJECTOR mean?
EJECTOR noun- One who, or that which, ejects or dispossesses.
- A jet jump for lifting water or withdrawing air from a space. {Ejector condenser} (Steam Engine), a condenser in which the vacuum is maintained by a jet pump.
- Ejector seat: a pilot's seat in an airplane that can be forcibly ejected in the case of an emergency; then the pilot descends by parachute.
- That part of the mechanism of a breech-loading firearm which ejects the empty shell.
- A lever for removing circuit boards from an electronic chassis.