Bus seating system

1. An interchangeable passenger seat for a vehicle, the vehicle having a seat-mounting surface comprising:

a base frame having at least one end member attachable to the seat-mounting surface of the vehicle and at least one cross-member extending generally perpendicularly from the end member;

at least one back frame removably attachable to the base frame; and

an adaptor bracket disposed around the cross-member, the adaptor bracket having a plurality of locating structure along the length of the adaptor bracket for selectively locating and attaching components of passenger restraint systems wherein the adaptor bracket comprises a top bracket portion and a bottom bracket portion that are hinged together, wherein the bottom bracket portion has a first central channel configured for receiving the cross-member, a first generally planar lip extends from one side of the first central channel, and a plurality of hooking elements extend from the opposite side of the first central channel.

2. The interchangeable passenger seat of claim 1 wherein the back frame is attachable to the base frame at a receiving structure extending upward from the end member.

3. The interchangeable passenger seat of claim 1 wherein the base frame comprises two cross-members including a forward cross-member and a rearward cross-member, wherein the rearward cross-member is located closer to the back frame than the forward cross-member, and the adaptor bracket is disposed around the rearward cross-member.

4. The interchangeable passenger seat of claim 1 wherein the adaptor bracket substantially encapsulates the cross-member and extends substantially the length of the cross-member.

5. The interchangeable passenger seat of claim 1 wherein the top bracket portion has a second central channel for receiving the cross-member, and a plurality of hook-receiving holes disposed on a side surface of the second central channel and spaced along the length of the top bracket portion, wherein the hook receiving holes receive the plurality of hooking elements on the bottom bracket portion.

6. The interchangeable passenger seat of claim 5 wherein the plurality of locating structure are disposed on the side surface of the second central channel of the top bracket portion, wherein the locating structure are attachment holes for fastening components of the passenger restraint system.

7. The interchangeable passenger seat of claim 5 wherein the first generally planar lip of the bottom bracket portion engages with a second generally planar lip portion that extends from the second central channel of the top bracket portion.