Here are some of the craziest planes the US military has flown — or tried to fly

• The iconic aircraft the US Air Force has flown since World War II are still widely know.
• What are less known are the more outlandish aircraft the military has tried to use, some of which didn’t make it to the fleet.
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A number of American planes have become classics. We know them off the top of our head: the P-51 Mustang, the F4U Corsair, the B-17 Flying Fortress. We can go on and on, and even debate amongst ourselves which planes were the coolest.

Some, though, are just plain crazy. You have to wonder Whiskey Tango Foxtrot were they thinking when they tried to fly `em. Was there ever any hope of them working? Here’s a look at a few — but just because they look crazy doesn’t mean some of them didn’t work.

McDonnell F-85 Goblin

Early jet fighters were a lot like sprinters. They were fast, but they didn’t have a lot of range. So some folks had the bright idea of having the bomber bring along its fighter escort. The “parasite fighter” was intended to be carried in by a bomber, be discharged, fight off enemy planes, then hook back up with the bomber.

The ultimate expression was the F-85 Goblin. This plane weighed less than 5,000 pounds, and was armed with four .50-caliber machine guns. It made a total of seven flights before the program was cancelled. Why? Aerial refueling was perfected, and making bombers trade off a lot of their payload to carry their fighter escort was no longer necessary.

Northrop B-35 and B-49

We see the B-2 today as perhaps the ultimate high-tech bomber. But Northrop had been trying to make a flying wing work since World War II. The B-35 and B-49 looked futuristic — and indeed they were decades ahead of their time. In this case, that was literally their problem.

The flying wing had its benefits, but the problem was the technology wasn’t there yet. The crash of a YB-49 prototype helped put the flying wing into limbo, not to return until the B-2 program, when computers enabled the flying wing to fly.

NB-36H Peacemaker

In one sense, the B-36 arguably made the legendary B-52 Stratofortress look puny. However, that plane took a lot of fuel to get off the ground and to keep flying. Fuel can get expensive, and its flammable. So they decided to see if they could use nuclear power. The NB-36H was built to test the concept.

The reactor weighed 35,000 pounds. But after test flights, the Air Force decided that jet fuel was still a better option. Besides, they were buying some of the first of 732 KC-135 tankers.

C-5 Galaxy

The C-5 Galaxy is crazy, all right. Crazy huge. The Air Force fact sheet on this plane lays it all out: It is 247 feet long, 65 feet high, and has a wingspan of just under 223 feet. The Air Force built 126 of these planes: 76 C-5As from 1968-1973, and 50 C-5Bs from 1985-1989.

It can be refueled while flying, but even when carrying 60 tons, it can fly 4,800 nautical miles. Currently the Air Force has 78 C-5s on inventory. But when you have something that can haul as much as 135 tons of cargo in one go, maybe it wouldn’t hurt to build more.

F-117 Nighthawk

This plane falls into the crazy-enough-to-work category. Just looking at it, you think it wouldn’t even fly. Well, it could, and it is one of the crown jewels to emerge from that famous Lockheed refinery known as the “Skunk Works.”

Often called the “Wobblin’ Goblin,” the F-117 was designed to have a very low radar cross-section. It ended up working very well for American pilots, easily penetrating Iraq’s vaunted air defense system.

One was lost over Yugoslavia during Operation Allied Force in 1999, but the F-117 served well, and the planes have still been flying despite having been “retired” in 2007.