Flight impressed Estonia's leader (8)
I believe the answer is:
stampede
'flight' is the definition.
(I've seen this before)
'impressed estonia's leader' is the wordplay.
'impressed' becomes 'stamped' (stamping is a kind of impressing).
'leader' suggests taking the first letters.
The first letter of 'estonia' is 'e'.
'stamped'+'e'='STAMPEDE'
(Other definitions for stampede that I've seen before include "unstable flight" , "Sudden mass rush" , "Uncontrolled rush" , "Pasted me (anag.)" , "Headlong rush of animals" .)