Branch specialised in launching carpeting line (8)
I believe the answer is:
rocketry
'branch specialised in launching' is the definition.
(I've seen this before)
'carpeting line' is the wordplay.
'carpeting' becomes 'rocket' (I can't explain this - if you can you should give a lot more credence to this answer).
'line' becomes 'ry' (abbreviation for railway).
'rocket'+'ry'='ROCKETRY'
Can you help me to learn more?
(Other definitions for rocketry that I've seen before include "Branch specialised in launching" , "Study of space vehicles" , "Complex science" , "Science concerned with missiles" , "Clever science" .)