 YAS also has over 450 Patient Transport Service (PTS) vehicles which are operated by around 696 PTS staff.YAS can deploy rescue helicopters, including two Airbus H145s of the Yorkshire Air Ambulance to emergencies and incidents across the service area, however the Air Ambulance Service is a charity and not an integral part of YAS – paramedics are provided by YAS and work on a rota with doctors who are voluntary members of the BASICS (British Association for Immediate Care) to offer additional medical skills.The Trust entered into a contract with Medical (Europe) Ltd of Malton trading as North of England Ambulance Service by which it could call on up to 13 ambulances, each with two crew members, to cover staff shortages in 2012.