Thursday, May 29, 2008
Touchdowns: Pregnant Plane Delivers
Kicking off the space race
On May 25, 1961, President John F. Kennedy announced his plans for the United States to put the first man on the moon by 1970. The space race officially shifted into high gear. His announcement also triggered events that led to the manufacture of one of the oddest looking planes in aviation history—the Pregnant Guppy, an aircraft that would help make Kennedy’s goal a reality.
Rocket engine boosters for the Saturn missions were made by Douglas Aircraft Company in Sacramento, Calif., and rockets were launched from Cape Canaveral, Fla. Because the boosters were so tremendous—40 feet long and 18 feet high—transporting them from one side of the country to the other was no small feat.
What land vehicle or train could manage such a cargo? Ships required 15 days to make the trip through the Panama Canal. Cargo aircraft could do it in a fraction of the time, but typical cargo planes could only carry machinery about half the booster’s size.
Jack Conroy, an “aviation visionary,” and Lee Mansdorf, a businessman who bought and sold aircraft, decided they were up to the task of creating a giant plane to transport such a sizable load. They created Aero Spacelines Inc. (ASI) and convinced Wernher von Braun, NASA’s rocketry chief, to hear their ideas. He gave them three days to make their proposal.
In September 1963, the Pregnant Guppy made its first flight for NASA. Its payload included the S-IV stage for the fifth Saturn I launch vehicle—a crucial contribution to the entire space program.
Conroy and Mansdorf’s plan was based on three stages using parts of Boeing 377 Stratocruisers and KC-97 Stratotankers. The first stage would lengthen the fuselage by 16 feet, eight inches. Stage two created a 19-foot, six-inch cargo area over the existing fuselage using internal bracing. After testing, they’d cut away the old fuselage and the temporary bracing. Von Braun was impressed and gave them the go-ahead to proceed.
In September 1963, the Pregnant Guppy made its first flight for NASA. Its payload included the S-IV stage for the fifth Saturn I launch vehicle—a crucial contribution to the space program. When it retired in 1974, the craft had logged more than 6,000 hours.
Even before the original Guppy made its first flight, NASA began negotiations with ASI for an even larger aircraft. These talks resulted in a series of Guppies: Super Guppy, Mini Guppy and Super Guppy Turbine.
Super Guppy had an inner diameter of 25 feet and a volume of 49,750 cubic feet, five times larger than a typical airplane at that time. It also used an unusual hinged nose that opened at 110 degrees. Mini Guppy featured a sleeker design with a hinged tail.
All but one Guppy are now retired. Super Guppy can be seen at Pima Air & Space Museum in Tucson, Ariz. Mini Guppy is part of the Erickson Collection at Tillamook Naval Air Station Museum. Super Guppy Turbine No. 1 is at the British Aviation Heritage Museum. No. 2 is in Toulouse, France, at Airbus Industrie’s final assembly plant, and No. 3 is on display at the Airbus assembly plant in Finkenwerder, Germany. Super Guppy Turbine No. 4 is owned by NASA and is the only Guppy still flying.