Castle takes full advantage of the beautiful California weather and expansive outdoor real estate, featuring many big aircraft rarely found at other museums. This B-24 Liberator was flown by the 93rd Bomb Group, which is the predecessor of 93rd Bomb Wing that was stationed at Castle Air Force Base.
One of the bigger aircraft at the museum, the Boeing KC-97 Stratofreighter, the tanker version of the C-97. Note the outboard pods under the wing. This is one of the few aircraft that has both propellers (4) and jets (2). The jets were only used for short periods to make refueling easier with faster aircraft.
Douglas redesigned and improved their B-18 (there's one of those here, too), to become the far superior B-23 like what you see here. Only 38 were built, however, as it was still outclassed by the B-25 and B-26.
Fixed-wing Air Force aircraft typically use this, called a flying boom. The "male" end is on the tanker, and the "female" end is on the aircraft. Navy and Marine aircraft typically have the opposite, called probe-and-drogue.
The A-3 Skywarrior is one of the heaviest aircraft ever to fly off US carriers, and in various roles, one of the longest-serving. This one is the RA-3B reconnaissance variant, and helped in the development of the Patriot missile.
If you're like me and you like big bombers and early SAC-era aircraft, Castle Air Museum is excellent. It's a bit of a hike to get to, about 2 hours from San Francisco or Sacramento, but as one of the few places in the world to see some of these aircraft, it's a fun diversion if you're on your way to or from Los Angeles. Especially if you time it during one of their open cockpit days.
For more info about these planes and the museum, check out Castles in the clouds: Big bombers and fast fighters at the Castle Air Museum