The 55-year-old member of Bollington Parascenders was hurt while undertaking a parascending launch at City Airport in Barton, Salford at 08:00 on Sunday.
Greater Manchester Police said the man had been taken to hospital with "life-threatening injuries".
A spokesman added the cause of the crash was "unclear" and asked anyone who witnessed it to get in touch.
Bollington Parascenders said members regularly fly parascending flights from City Airport in summer.
The British Hang Gliding and Paragliding Association said it would offer the police support if required to help with the investigation.
A paraglider has been critically injured in a crash at an airport, police have said.