I've been called many times to a scene, and turned around because they didn't need me after a full assessment. Sometimes the ambulance crew calls for a helicopter based only on what the situation sounds like, long before they get there, and it turns out to be a minor accident. We have arrived before the ambulance on some of those, and either circled until they made an assessment or landed and waited. We're a for-profit company, not a charity, but the cost of those flights is factored in to the overall budget, and probably makes money in the long run. I have never even considered the cost of a flight, because it does not matter at all to me. They call, I fly, and it's all the same to me and to the med crews. We far prefer being called early and turned around than being called too late. We use a hospital's helipad rather often to load a patient from an ambulance then go to another hospital, because the small country hospitals around here are not capable of handling major trauma, nor cardiac or stroke cases. They do fine with colds, flu, and minor illnesses and injuries, but if someone is really sick or hurt, they are not the place to go. I have no idea what the capabilities of your hospital are, but here there are 5 levels of trauma capability, and we would never consider going to anything lower than a 2, and not that often for that level. Being a newly renovated hospital does not make it capable of being a Level I trauma center. it's the availability of qualified staff, 24/7, that does that. It's an earned designation, and has to be maintained through audits afterwards. But again, I have no idea how this works in the UK.