The Spruce Goose, when at combat overload weight, weighed almost twice as much when empty as a fully loaded B-29 did during takeoff. For the time, they were simply absurd numbers
The Spruce Goose, the largest wooden aircraft ever built that has flown only once, is a symbol of one of humanity’s most ambitious attempts to dominate the skies. Hundreds of Allied ships were being sunk by German submarines in the Atlantic Ocean in 1942, therefore it became necessary to carry troops and materials across that region. The idea for a massive flying transport originated with shipbuilding and steel magnate Henry Kaiser, who hired Howard Hughes to design and construct it. Hughes took on the job, which was made more difficult by government limits on supplies like steel and aluminum that were essential to the war effort. The Spruce Goose often referred to as the Hughes Flying Boat, is entirely constructed of wood and is six times bigger than any aircraft of its era.
When Henry Kaiser withdrew from the project in 1944, the giant, which had been given the initial designation HK-1 for the first Hughes-Kaiser aircraft, was given the new designation H-4 Hercules.
‘While staying at the floating museum and passenger ship turned hotel, the RMS Queen Mary on a business trip I was able to tour the Spruce Goose (of which 90% was constructed out of Birch, not Spruce. But the media thought “spruce goose” had the right ring to hook readers and listeners),’ says Gregg Gray, former Senior Noncommissioned Officer (SNCO) in the US Air Force, on Quora. ‘As it was very close by where the Queen Mary is moored (when the aircraft was still in Long Beach, California) we felt compelled to go, she has a large drawing effect, its size is overwhelming (and I was then routinely flying on the huge Air Force jet cargo aircraft, the C-141B stateside and often the C-5B overseas, as well as the occasional Boeing 747 and the rare Lockheed L-1011 widebody; and I was staying on a huge ocean-going, luxury passenger ship). My military co-workers and I were just gobsmacked at the size of the aircraft.
‘The story we got from the tour guide was that at that time Hughes and his engineers were simply planning the day testing to collect data at faster surface speeds on the water, but it accidentally reach take-off speed and flew very briefly, and very low (but somehow managed to get its picture taken for the newspaper).
‘I speculate, as others do, that Howard Hughes, who was at the controls that day, did it on purpose just to see if it would actually fly. I think at that point he was already aware that the project was doomed to end and never go into production. It probably would not have seen service even if the war had continued. It appeared to be very problematic, as very large, complex, and complicated things tend to be, as well as a gas hog.’
Gray continues:
‘It was 3,700 miles from Norfolk Naval Yard to Southampton and 3,800 miles to La Rochelle, France. Amsterdam is 3,900 miles from Norfolk and Naples, and Italy is a staggering 4,650. (All of these are straight-line distances, as the crow [or seagull] flies, if I may improvise slightly]. The design flight range was 3,000 miles at 250 mph. So it was going to have to find a refueling ship in the open ocean or an intermediate island like the Azores at 2,751 miles, and then another 1,500 miles to Southampton (Way back in the day I flew on a piston engine, propeller-driven passenger aircraft from Scotland to the Azores, and on to New York, [then on to our car in Bayonne, NJ, followed by a drive to Tennessee to get back home to our family in Tennessee] we were very tired.). But just the flying portion by itself sucked, it wasn’t any fun at all, in fact, it was miserable and very cramped. The top speed hoped for out of the Spruce Goose was 250 mph, and realistically 200 mph was probably going to be achieved when fully loaded with combat troops in “Full Battle Rattle.” The proposed purpose was to avoid German U-boats sinking troop ships. This aircraft was still going to have to land in the water off the coast of the Azores, or on the high seas for a refueling ship. Now the miserable cramped, tired, and intolerant troops were one thing to deal with, after all, it was four days or more minimum on the cramped troop surface ships, so they would have to tolerate that. What they couldn’t tolerate was getting troops killed by U-boats lying in wait for the aircraft, and no matter where you landed that was an issue. Water landings by aircraft in a sea full of U-boats give the U-boat skippers an easy sitting duck (or goose in this case) for a target.
‘Flying for between 15 and 20 hours with just a short refueling break would have been exhausting. I have done it more than once, the Pentagon planned our flights to land just after daybreak so we could get in a full day’s work at our destination. What starts out as huge gets smaller as you go.
‘Now, not only is the aircraft huge now, but it was absolutely ginormous in the mid-1940s, she is almost 2.5 times as long, has three times the wingspan, and empty weighs more than triple what was then our huge Boeing B-29 United States Air Force Bomber, the Superfortress (of Hiroshima and Nagasaki atom bomb fame). The B-29 had four engines producing 8,800 horsepower together, the Spruce Goose achieved 24,000 total horsepower from “8 × Pratt & Whitney R-4360 Wasp Major 28-cylinder air-cooled radial piston engines, 3,000 hp (2,200 kW) each.” It required three times as much horsepower because it was well over three times heavier at 250,000 pounds versus the Superfortess at 74,500 pounds. In fact, empty the Spruce Goose weighed almost twice what a fully loaded B-29 weighed at takeoff when at combat overload weight. They were just insane numbers for the era. It was another 20+ years before the big C-5A Galaxies and 747s came along which are in the same size range as the enormous H-4 Hercules (Spruce Goose). ‘
Gray concludes;
‘As neat as all the specifications are, she still comes up short. I don’t think it would have worked as a troop transport. Nowadays we just charter civilian passenger jets for routing troops deployments. The military cargo birds are busy moving heavy equipment and helicopters. Military cargo birds are usually used for pax when the troops have to deploy in full battle rattle and prepared for almost instant action.’
The Spruce Goose is now housed at the Evergreen Aviation & Space Museum near McMinnville, Oregon.
The following interesting video features the first and last flight of the Spruce Goose.
Photo by Federal Aviation Administration
