Hughes H-4 Hercules

H-4 Hercules
Role Heavy transport flying boat
Manufacturer Hughes Aircraft
First flight November 2, 1947
Produced 1947
Number built 1
Career
Other name(s) "Spruce Goose"
First flight November 2, 1947
Flights 1
Preserved at Evergreen Aviation Museum

The Hughes H-4 Hercules (registration NX37602) ("Spruce Goose") was a prototype heavy transport aircraft designed and built by the Hughes Aircraft company. The aircraft made its only flight on November 2, 1947. Built from wood because of wartime raw material restrictions on the use of aluminum, it was nicknamed the "Spruce Goose" by its critics.[1] The Hercules is the largest flying boat ever built, and has the largest wingspan of any aircraft in history.[2] It survives in good condition at the Evergreen Aviation Museum in McMinnville, Oregon, USA.

Despite its nickname, the H-4 was built almost entirely of birch, rather than spruce. The plywood-and-resin "Duramold" process,[3] a form of composite technology, was used in the laminated wood construction, which was considered a technological tour de force.[4] The aircraft was not finished in time for use in World War II and never advanced beyond the single prototype produced.

Contents

Design and development

Size comparison between H-4 and a DC-3

In 1942, the U.S. Department of War was faced with the need to transport war matériel and personnel to Britain. Allied shipping in the Atlantic Ocean was suffering heavy losses to German U-boats, so a requirement was issued for an aircraft that could cross the Atlantic with a large payload. Due to wartime priorities, the design was further constrained in that the aircraft could not be made of metal.

The aircraft was the brainchild of Henry J. Kaiser, who directed the Liberty ships program. He teamed with aircraft designer Howard Hughes to create what would become the largest aircraft built at that time. When completed, it was capable of carrying 750 fully-equipped troops or one M4 Sherman tank.[5] The original designation "HK-1" reflected the Hughes and Kaiser collaboration.[4]

The HK-1 contract in 1942, issued as a development contract,[6] called for three aircraft to be constructed under a two-year deadline in order to be available for the war effort.[7] Seven configurations were considered, including twin-hull and single-hull designs with combinations of four, six and eight wing-mounted engines.[8] The final design chosen was a behemoth, eclipsing any large transport then built.[6][9] To conserve metal, it would be built mostly of wood (elevators and rudder were fabric covered[10]); hence, the "Spruce Goose" moniker tagged on the aircraft by the media. It was also referred to as the Flying Lumberyard by critics. Hughes himself detested the nickname "Spruce Goose".[11]

While Kaiser had originated the "flying cargo ship" concept, he did not have an aeronautical background and deferred to Hughes and his designer, Glenn Odekirk.[9] Development dragged on, which frustrated Kaiser, who blamed delays partly on restrictions placed for the acquisition of strategic materials such as aluminum, but also placed part of the blame on Hughes' insistence on "perfection."[12] Although construction of the first HK-1 had taken place 16 months after the receipt of the development contract, Kaiser withdrew from the project.[11]

Rearward view of the Hercules H-4's fuselage
Brazoria County Airport Texas: The S-43 Sikorsky test plane for the Spruce Goose

Hughes continued the program on his own under the designation "H-4 Hercules" (initially identified as the HFB-1 to signify Hughes Flying Boat, First Design,[10]) signing a new government contract that now limited production to one example. Work proceeded slowly, with the result that the H-4 was not completed until well after the war was over. It was built by the Hughes Aircraft Company at Hughes Airport, location of present day Playa Vista, Los Angeles, California.

In 1947, Howard Hughes was called to testify before the Senate War Investigating Committee over the usage of government funds for the aircraft.

During a Senate hearing on August 6, 1947 in the first of a series of appearances, Hughes said:

The Hercules was a monumental undertaking. It is the largest aircraft ever built. It is over five stories tall with a wingspan longer than a football field. That's more than a city block. Now, I put the sweat of my life into this thing. I have my reputation all rolled up in it and I have stated several times that if it's a failure I'll probably leave this country and never come back. And I mean it.[13]

Operational history

Hughes H-4 Hercules on its maiden flight

During a break in the Senate hearings, Hughes returned to California to run taxi tests on the H-4.[10] On November 2, 1947, the taxi tests were begun with Hughes at the controls. His crew included Dave Grant as co-pilot, and two flight engineers, 16 mechanics and two other flight crew. In addition, the H-4 carried seven invited guests from the press corps plus an additional seven industry representatives, for a total of 32 on board.[14]

After the first two taxi runs, four reporters left to file stories, but the remaining press stayed for the final test run of the day.[15] After picking up speed on the channel facing Cabrillo Beach near Long Beach, the Hercules lifted off, remaining airborne 70 ft (21 m) off the water at a speed of 135 miles per hour (217 km/h) for around a mile (1.6 km).[16] At this altitude, the aircraft was still experiencing ground effect.[17] The aircraft never flew again. Its lifting capacity and ceiling were never tested. A full-time crew of 300 workers, all sworn to secrecy, maintained the plane in flying condition in a climate-controlled hangar. The crew was reduced to 50 workers in 1962, and then disbanded after Hughes' death in 1976.[18]

Display and legacy

Hercules at Evergreen Aviation Museum

In 1980, the Hercules was acquired by the California Aero Club, who put the aircraft on display in a large dome adjacent to the Queen Mary exhibit in Long Beach, California. In 1988, The Walt Disney Company acquired both attractions and the associated real estate. Disney informed the California Aero club that they no longer wished to display the Hercules. After a long search for a suitable host, the California Aero Club awarded custody of the Hughes flying boat to Evergreen Aviation Museum. Under the direction of museum staff, the aircraft was disassembled and moved by barge to its current home in McMinnville, Oregon (about one hour southwest of Portland) where it has been on display ever since. The Flying Boat arrived in McMinnville at Evergreen International Aviation on February 27, 1993 after a 138-day, 1,055-mile trip from Long Beach.

By the mid-1990s, the former Hughes Aircraft hangars at Hughes Airport, including the one that held the Hercules, were converted into sound stages. Scenes from movies such as Titanic, What Women Want, and End of Days have been filmed in the 315,000 square foot (29,000 m²) aircraft hangar where Howard Hughes created the flying boat. The hangar will be preserved as a structure eligible for listing in the National Register of Historic Buildings in what is today the large light industry and housing development Playa Vista in suburban Los Angeles, California.

Although the project did not move beyond the initial prototype, the H-4 Hercules was a forerunner of the massive transport aircraft of the late 20th century, such as the Lockheed C-5 Galaxy, the Antonov An-124, and the An-225.

Specifications (H-4)

Performance specifications are projected.

Pratt & Whitney R-4360 Wasp Major

General characteristics

Performance

Notable appearances in media

In the film The Rocketeer (1991), hero Cliff Secord uses a large-scale model of the Hercules to escape some eager federal agents and Howard Hughes himself. After Secord glides the model to safety, Hughes expresses astonishment that the craft might actually fly.[19] The construction and flight of the Hercules was featured in the Hughes 2004 biopic The Aviator. Motion control and remote control models, as well as partial interiors and exteriors of the aircraft, were reproduced for this scene. The motion-control Hercules is on display at the Evergreen Aviation Museum, next to the real Hercules.

A size comparison between four of the largest aircraft: the An-225 (green); the Hughes H-4 Hercules (gold); the Boeing 747-8 (blue); and the Airbus A380-800 (pink).

See also

Comparable aircraft

Related lists

References

Notes
  1. article in The Aviation Zone
  2. "Spruce Goose." Evergreen Aviation Museum. Retrieved: May 26, 2010.
  3. Winchester 2005, p. 113. The Hughes Corporation had utilized the duramold process which laminated plywood and resin into a lightweight but strong building material that could be shaped.
  4. 4.0 4.1 Odekirk 1982, p. II.
  5. McDonald 1981, p. 41.
  6. 6.0 6.1 McDonald 1981, p. 45.
  7. Odekirk 1982, p. 1V.
  8. McDonald 1981, pp. 41–44.
  9. 9.0 9.1 McDonald 1981, p. 40. Quote: "Kaiser announces the most monumental program in the history of aviation."
  10. 10.0 10.1 10.2 Winchester 2005, p. 113.
  11. 11.0 11.1 McDonald 1981, pp. 58–59.
  12. McDonald 1981, p. 56.
  13. The Great Aviator: Howard Hughes, His Life, Loves & Films — A Documentary. Los Angeles: Delta Entertainment Corporation, 2004. Note: Hughes' Senate Hearings testimony is now in the public domain.
  14. McDonald 1981, pp. 78–79.
  15. McDonald 1981, pp. 85–87.
  16. Francillon 1990, pp. 100, 102.
  17. Wing In Ground effect aerodynamics
  18. Dean, Paul. "The Man Who Keeps The Spruce Goose." Los Angeles Times, April 21, 1983, p. J1.
  19. David 1991
Bibliography
  • David, Peter. The Rocketeer: The Official Movie Adaptation. Burbank, CA: W D Publications Inc., 1991. ISBN 1-5685-190-4.
  • Francillon, René J. McDonnell Douglas Aircraft since 1920: Volume II. Annapolis, MD: Naval Institute Press, 1990. ISBN 1-55750-550-0.
  • McDonald, John J. Howard Hughes and the Spruce Goose. Blue Ridge Summit, PA: Tab Books Inc., 1981. ISBN 0-8306-2320-5.
  • Odekirk, Glenn E. Spruce Goose (Title inside cover: HK-1 Hercules: A Pictorial History of the Fantastic Hughes Flying Boat). Long Beach, CA: Glenn E. Odekirk and Frank Alcantr, Inc., 1982. No ISBN.
  • Schwartz, Milton L.The Spruce Goose Commemorative Pictorial. Oakland, CA: The Wrather Corporation by Mike Roberts Color Productions, 1983
  • Winchester, Jim. "Hughes H-4 'Spruce Goose'." Concept Aircraft: Prototypes, X-Planes and Experimental Aircraft. Kent, UK: Grange Books plc., 2005. ISBN 1-84013-309-2.
  • Yenne, Bill. Seaplanes & Flying Boats: A Timeless Collection from Aviation's Golden Age. New York: BCL Press, 2003. ISBN 1-932302-03-4.

External links