How come Howard Hughes’s “Spruce Goose” flew only once?

Dear Cecil: Howard Hughes’s H-4 (the “Spruce Goose”) flew only one time, in 1947. Somewhere it was written that Hughes detected a vibration or pulsating in the aircraft frame or in the control wheel right after he lifted off and decided to set the H-4 back down rather than take a big risk that it would be uncontrollable if he gained more altitude. It was also said that he was just proving that it would indeed fly for the senators and that he just wanted to prove it by flying only a very short distance. What is the straight dope? Marvin Moss

Cecil replies:

I know what you’re thinking. Well, maybe not what you’re thinking, Marvin, since you sound like an aviation buff. However, the average person is thinking: Of course Howard Hughes flew the Spruce Goose only once (it wasn’t spruce, by the way — it was mostly made out of birch). By far the biggest airplane ever built, the H-4, also known as the Hercules, had a wingspan of 320 feet — 20 feet longer than a football field. It had enough cargo space to carry two railroad boxcars. It had eight massive engines with 17-foot propellers. It weighed 300,000 pounds. And it was made of wood. They make, or at least made, toy gliders out of wood, not real aircraft. Hughes was lucky the wings didn’t break off during the first flight.

Shows you what the average person knows. As late as 1977, the party that commissioned the H-4, the U.S. government, was thinking about flying it again. Great, the U.S. government almost embarrassed itself twice, you’re thinking. (Not you, Marvin. The average guy.) I’m not saying the design didn’t have its problematic aspects. But it wasn’t as crazy as some might believe.

The idea for a giant seaplane was initially championed by industrial magnate Henry Kaiser, who had masterminded the Liberty Ship construction program, which cranked out freighters in an unbelievable 48 days (record: five days). Kaiser wanted to transport war materiel overseas by air, where it would be safe from enemy torpedoes. But he knew nothing about airplane building and was happy to hook up with Hughes, who’d assembled a team of crack aeronautics engineers that, among other things, helped him design a plane that set a speed record in 1935. Despite opposition from the military and the aircraft industry, Kaiser and Hughes landed a government contract to build three prototype planes. The catch: the long-shot project could make only minimal use of strategic materials such as metals. That meant using wood, common in small aircraft but untested in one so large.

Hughes’s eccentricities hobbled the project from the start. Kaiser found his partner impossible to work with and was relegated to the sidelines. Hughes micromanaged every design detail, and work soon fell far behind schedule. By early 1943 the metals shortage had eased and many urged that aluminum be substituted for wood, but Hughes, apparently enamored of the advanced plywood fabrication methods his team had developed, declined to switch. Skeptics almost succeeded in killing the project in 1944, but somehow Hughes got the OK to continue. The war ended before the plane was assembled into one piece. The project dragged out until 1947, when a U.S. Senate committee began investigating Hughes for defense contract irregularities, particularly regarding the Spruce Goose. As if to demonstrate that he hadn’t defrauded the government, Hughes, who always test-piloted his own planes, flew the H-4 about a mile in less than a minute during what was supposed to be a taxiing test on November 2.

Why did Hughes never fly the plane again? Some said he was afraid to, but his closest associates denied it. The more likely explanation is that there was no reason to continue. The war was long over. The need for big seaplanes had evaporated. Wood construction was obviously a dead end. Even before the flight Hughes admitted that the plane was too large to be economical. Claiming there were still research lessons to be learned, he stubbornly kept the work going until around 1952. But he was distracted by other ventures and increasingly reclusive. Eventually everyone moved on to other things. After Hughes’s death in 1976, the plane was put on exhibit and now may be seen at the Evergreen Aviation Museum in McMinnville, Oregon.

Was the Spruce Goose an impractical boondoggle? Absolutely. Was it completely off the wall? No. The plane was flyable — no small point. In fact, in 1977 the U.S. Navy seriously considered test flights with the H-4 as part of research into low-altitude transoceanic flight. Didn’t happen, which is probably just as well. But one thing you have to give Howard Hughes: he may have been crazy, but he was no fool.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.