A floatplane crashed into Ketu Bay in the Marlborough Sounds on Thursday evening.

A 55-year-old Picton man has been flown to hospital with serious injuries after crashing his floatplane in the Marlborough Sounds.

The Nelson-Marlborough Rescue Helicopter flew the man to Nelson Hospital after his floatplane crashed on landing near Ketu Bay on Thursday evening.

The nurse duty manager at Nelson Hospital confirmed the man was discharged later in the evening.

Emergency services were called about 5.40pm after reports of the incident began to emerge.

A local water taxi crew who had arrived on the scene helped get the man to the waiting helicopter.

The man was assessed and treated by the on-board intensive care paramedic before being airlifted to hospital in a serious condition.