The “Spruce Goose”: Howard Hughes’ Remarkable and Enigmatic Wooden Aircraft

The Hughes Flying Boat H-4 (HK-1) Hercules a.k.a. The "Spruce Goose"

Fun Facts About the Spruce Goose

Names: Hughes Flying Boat H-4 (HK-1) Hercules (“Spruce Goose”)

Description: The Hughes Flying Boat is a cargo-type seaplane designed to transport men and materials over long distances. This aircraft is of a single hull, eight-engine design, with a single vertical tail, fixed wing-tip floats, and full cantilever wing and tail surfaces. The entire airframe and surface structures are composed of laminated wood (primarily birch). All primary control surfaces except the flaps are fabric covered. The hull contains two areas: a flight deck for the operating crew and a large cargo deck. A circular stairway provides access between the two decks. Below the cargo deck are fuel bays divided by watertight bulkheads.

Largest wingspan: 319 feet, 11 inches with a wing area that covers 11,430 square feet
Features full cantilever wing and tail surfaces.

Tallest aircraft: 79 feet, 3 3/8 inches

Length: 218 fee 6 ¼ inches

Record setting: Largest seaplane and largest wooden aircraft: the entire airframe is composed of laminated wood. Primary control surfaces, except the flaps, are fabric-covered. The most reciprocating horsepower ever installed in an aircraft.

Power: Eight Pratt & Whitney R-4360, 3,000 horsepower engines

Propellers: Eight, 17 feet, 2 inch diameter

Weight, Empty: 300,000 pounds

Weight, Loaded: 400,000 pounds (maximum take-off weight)

Capacity: 750 troops or two Sherman tanks

Normal Crew: 18

First And Only Flight: November 2, 1947

Howard Hughes in the cockpit of the Spruce Goose

Why built: In July 1942, the world was at war. America had just lost 800,000 tons of her supply ships to German U-boats. Henry Kaiser, famed industrialist and builder of “Liberty” ships, proposed a fleet of flying transports to safely move troops and material across the Atlantic. Kaiser approached Howard Hughes with his idea. Together they formed the Hughes Kaiser Corporation and obtained an $18,000,000 government contract to construct three flying boats.

Hughes and his team of skilled engineers designed a single hull flying boat capable of carrying 750 troops. The plans called for eight 3,000 horsepower engines, a mammoth fuel storage and supply system, and wings 20 feet longer than a football field. They called the prototype aircraft the HK-1, standing for the Hughes Kaiser design number one.

Delays and Constraints: Encountering and dealing with tremendous design and engineering problems, the Hughes team developed new concepts for large-scale hulls, flying control surfaces, and complex power boost systems. Hughes engineers created the first “artificial feel system” in the control yoke, which gave the pilot the feeling he was flying a smaller aircraft, but with a force multiplied two hundred times. For example, for each pound of pressure exerted on the control yoke by the pilot, the elevator received 1,500 pounds of pressure to move it.

The H-4 now resides at the Evergreen Aviation & Space Museum in McMinnville, OR

Adhering to the government mandate not to use materials critical to the war effort (such as steel and aluminum), the Hughes team constructed the Flying Boat out of wood. Hughes perfected a process called “Duramold” to create almost every part of the plane. Originally developed by Fairchild Aircraft Company, Howard Hughes purchased the rights to use Duramold in large aircraft. The Duramold process is a plywood-like series of thin wood laminations, with grains laid perpendicular to each other. Workers permeating the laminations with plastic glue, then they shaped and heated the pieces until cured. The result is a material that many engineers agree is both lighter and stronger than aluminum.

All of the research and development that went into the new seaplane delayed the construction process. In mid 1944, Henry Kaiser withdrew from the project, and Hughes took personal responsibility for all facets of the flying boat’s design and production. He renamed the gigantic seaplane H-4, representing his aircraft company’s fourth design.

After the war’s end in 1945, criticism of the project mounted. The Flying Boat prototype had exceeded the government’s funding allowance and the U.S. Senate formed an investigation committee to probe alleged misappropriation of funds. Hughes invested $7,000,000 of his own into the project to keep it going. While Hughes testified before the investigative committee in Washington, D.C., the Hughes team assembled the Flying Boat in the Long Beach dry dock. After his interrogation, Hughes was determined to demonstrate the capability of his Flying Boat. He returned to California and immediately ordered the seaplane readied for taxi tests.

Proof of Concept: On November 2, 1947, a crowd of expectant observers and newsmen gathered. With Hughes at the controls, the giant Flying Boat glided smoothly across a three-mile stretch of harbor. From 35 miles per hour, it cruised to 90 during the second taxi test when eager newsmen began filing their stories. During the third taxi test Hughes surprised everyone as he ordered the wing flaps lowered to 15 degrees and the seaplane lifted off the water. He flew her for a little over a mile at an altitude of 70 feet for approximately one minute. The short hop proved to skeptics that the gigantic craft could fly!

 

Special thanks to www.sprucegoose.org

The Panama Canal: Connecting Two Oceans and Innovating Travel

Promotional Poster for the Canal

Fun Facts About The Panama Canal

• The canal opened on July 12, 1920.

• Ships traveling between New York and San Francisco save 7,872 miles by using the Panama Canal instead of going around Cape Horn.

• The Atlantic entrance to the Canal is 22-1/2 miles west of the Pacific entrance.

• More than four and half million cubic yards of concrete went in to the construction of the locks and dams.

• Material originally excavated to build the Canal were put on to a train of flat cars, it would encircle the world four times.

• The locks of the Panama Canal are seven feet thick.

• Each door of the locks weights 750 tons.

• Due to the reclining “S” shape of the Isthmus of Panama the sun rises from the Pacific and sets in the Atlantic Ocean.

• The average sea level for the Atlantic and Pacific entrance is virtually the same. But since the tidal variation at the Pacific entrance can be up to 18 feet, a sea level canal would be faced with the problem of a current running northbound when the Pacific tide was high and a current running south bound when the tide was low.

• On February 29, 1968 the most transits on a single day with an amount of 65 ships crossing the isthmus was recorded.

• In June 1979 the U.S. Navy hydrofoil Pegasus made the fastest transit ever when it crossed the Panama Canal in record time of 2 hours and 41 minutes.

• Approximately 7,300 or nearly 92 percent of the work force of the Panama Canal is Panamanian.

• The 13,700 transit in 1996 carried more than 198 million long tons of cargo to ports throughout the world.

• More than 60,000,000 pounds of dynamite was used to excavate and construct the Panama Canal.

• The dam constructed across the Chagres River in Gatun created Gatun Lake , the largest man-made lake in the world at that time.
  

  Gatun Locks

• The rock and soil excavated from Culebra cut was used to build the shell of the dam at Gatun on the Atlantic side.

• Since 1904 due to accidents and health problems, 5609 workers lost their lives, constructing the Canal. 80% of them were Black and 350 were white Americans.

• On August 23, 1928 Richard Halliburton transited the Canal swimming , paying a toll of 36 cents since his weight was 150 pounds.

• The cruise ship Rhapsody of the Sea established a toll record in 1997 when it paid $153,662.66 to cross the water-way.

• The San Juan Prospector was the longest ship to transit the Canal; it was 751 ft. (229 m.) in length with a 107 ft. (32.6 m.) beam.

• In 1963 the Panama Canal for the first time started operating on a 24 hour, round-the-clock schedule, thanks to the introduction high mass fluorescent lighting.

• The Panama Canal in 1974 raised the toll rates for the first time since they were not breaking even.

• Excavation of the Canal was equal to digging a 10 feet trench deep by 55 wide from California to New York.

Special thanks to  web.bryant.edu and www.panamatours.com