I do have an HWH hydraulic/air leveling system in my coach.  I like the idea of an independent air compressor as suggested in the earlier post.  When I park and level the coach, I dump the air bags and then level with the hydraulic.  If I use the compressor now while parked, I start the engine, leaving the hydraulic jacks down.  When finished with the need for air, I turn the engine off and dump the air bags and the coach settles down on the already extended hydraulic jacks.  It does return to the same level as before.   I was just hoping I could avoid the up and down part of that process.  I like the idea of an independent compressor as suggested in the earlier post.  Thanks to all for the input.