Rudimentary airline? That's not my fault! (5)
I believe the answer is:
basic
'rudimentary' is the definition.
(similar in meaning)
'airline? that's not my fault' is the wordplay.
I cannot really understand how this works, but
'airline?' could be 'ba' (British Airways) and 'ba' is located in the answer.
The remaining letters 'sic' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for basic that I've seen before include "Staple; ordinary" , "Popular programming language" , "Fundamental, elementary" , "Elemental" , "essential" .)