I don't even thing they had an Air Force 1 when Bush was President.
I remember them driving to Crawford Texas.
The Bushes might have driven to Crawford, but only from the nearest airport that could accommodate the two 747’s that comprise what we call AF1. We’ve had an AF1 (or dedicated presidential plane) since FDR.
When the Bushes returned to Crawford after BHO’s inauguration, it was on the same plane that he’d flown in as AF1 for 8 years, but since he was no long POTUS, the plane was renamed for that flight. The plane is ONLY AF1 when the POTUS is on board.