One appointed as first controller of Hercules among many (4,5)
I believe the answer is:
test pilot
'hercules among many' is the definition.
I can't tell whether this defines the answer.
'one appointed as first controller' is the wordplay.
'one appointed as' becomes 'test' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'first' means one lot of letters go next to another.
'controller' becomes 'pilot' (I have seen 'Controller of aircraft' mean 'pilot' so perhaps 'controller' could also mean 'pilot').
'test'+'pilot'='TEST-PILOT'
'of' is the link.
Can you help me to learn more?
(Other definitions for test pilot that I've seen before include "highflying expert" , "Airman" , "one occupying 21 [COCKPIT]" , "Highly dangerous job" , "one examining details of flight, spin, etc" .)