South Yorkshire residents are being invited to have their say in the future of Sheffield Airport.
The study into the airport's viability is expected to take six months
The city council has set up a six-month independent review into the airport's viability - taking into account the opening of Robin Hood airport nearby.
Sheffield airport has not carried out commercial flights since late 2001 but recently submitted an application to set up a heliport.
Residents have until 14 February to make their views known.
The review, carried out by York Aviation, was set up in 2004 after proposals for the new Blue Skies Business Park caused much debate and some opposition from residents.
The airport would have to be redesigned for it to operate as a heliport.
Robin Hood Airport, near Doncaster, opens in the spring and is expected to cater for 2.3m passengers and 50,000 tonnes of freight each year.