Paramedics were called to the Barwon Heads Airport in Connewarre, on the Bellarine Peninsula, after the man landed there about 11am.

Ambulance Victoria spokesman John Mullen said the man, aged in his 30s, had experienced a "sudden descent".

"He's hit the ground pretty heavily," Mr Mullen said.

"He's suffered pelvic and leg injuries and he also had a knock to his head."

Mr Mullen said the man was conscious and breathing and was flown by air ambulance to The Alfred hospital in a serious but stable condition.