The present invention is related to cargo vehicles add, more particularly, to cargo vehicles which are adapted to facilitate loading and unloading of cargo thereonto and therefrom as well as support the same for transportation. 
Air cargo loading and unloading from an airplane and transportation of such cargo to a terminal or the like typically utilizes a trailer or cart.  The cargo is manually loaded onto and removed from such trailers.  In the air cargo transportation business, large, cumbersome and heavy containers are frequently used for storing cargo.  Ordinarily, such a trailer is towed by a tractor.  The trailer includes a frame structure which has a mounting structure, wherein the cargo containers are lifted onto and removed therefrom.  Because of the weight and shape of such containers, considerable lifting effort is expended by workers during the loading and unloading procedure. 
Also, in the prior art there are several types of cargo vehicles which facilitate loading and unloading of containers and the like.  Some of these trailers are provided with pivoted loading plates or ramps which allow sliding movement of the containers relative thereto.  While this approach is successful in reducing the work involved in handling the containers there are, nevertheless, drawbacks associated therewith.  For example, some cargo containers are not easily slidable or movable on ramps.  Besides, considerable worker effort in lifting is still required, despite the ramp.  Then, of course, considerable time is expended as well. 
Other types of cargo carrying devices rely upon a loading platform which is elevatable to adjust for different loading/unloading heights.  Exemplary patents illustrating apparatus of the foregoing type are described in U.S. Pat.  Nos.  2,835,502; 3,795,336 and 4,063,745.  Such apparatus, however, tend to be relatively complicated in construction.  Accordingly, there is ongoing interest in providing for improvement in apparatus which simplifies the loading and unloading of cargo.  Moreover, there is interest in providing improved mechanisms for releasably retaining carried cargo on such vehicles.