The helicopter shares the same design as the Armadillo, but sports different livery. Its real-life equivalent is the Bell 412 helicopter. The air ambulance shares the same handling and speed as an Armadillo. It has good speed with steep pitches that allow it to help increase the acceleration and to keep it from losing altitude faster.
During the development of Grand Theft Auto: Vice City, the Air Ambulance was going to be made as a Coastguard Maverick, but the helicopter was removed before the game's release.
GTA Vice City Stories