I really must be missing something. Why on earth can you not transport patients if there's no ambulance available? Sure, it makes sense that patients with back or neck injuries can't be transported in an FRU as there isn't enough room for a spinal board but for the majority of other ailments, it stinks to me of blatant inefficiency to tie you up sitting with a patient rather than blueing them into a hospital. I think I'd be rather pissed off if I was having a fit/attack and the paramedic that arrived refused to take me into hospital because he was in a car rather than an ambulance.