The chairman of the Thames Valley Air Ambulance Trust, who resigned this week amid a fundraising crisis, has called for a joint service with the police to help keep emergency helicopters in the skies.

Pamela Tomlinson and the other trustees of TVAAT resigned on Wednesday, claiming there was a lack of communication between the trust, the Royal Berkshire Ambulance NHS Trust and the National Association of Air Ambulance Services (NAAAS). This had prevented the trustees from raising enough funds to keep the Agusta helicopter, which costs 720,000 a year to run, in the skies.

She said: "After a year of operational use, which has seen the air ambulance provide a valuable contribution to healthcare in the region, it has become clear that without total co-operation between all the parties involved, it will prove extremely difficult, if not impossible, to raise the level of funding needed to finance the aircraft and its operation. "It may well be the case that it would be more effective and just as medically effective to operate a joint emergency aircraft with Thames Valley Police."

The trustees claim they were not told when the air ambulance's Agusta A109 helicopter crash-landed in June, or that the NAAAS had grounded the temporary replacement aircraft, the Squirrel, in August because of contractural problems, or that the NAAAS agreed terms a week ago to put the aircraft back into service.