MIAMI — In the pantheon of bizarre looking airplanes, the Super Guppy is likely to be in the top three.  With its bulbous, bare metal cargo compartment, the airplane turns heads everywhere it goes. Airchive recently the spotted the aircraft in Seattle, where it picked up a composite rocket fuel tank, and decided to research the history behind this unusual airplane.

With the space race well under way in the early 1960s, NASA needed a more efficient way to transport the enormous Saturn V rocket boosters. With neither rail nor road proving to be viable options, the space agency had to ship the giant parts from their assembly plant in California to the launch site in Florida via the Panama Canal. At the time there was no airplane big enough to do the job.

Enter Lee Mansdorf, a businessman who dealt in aircraft and conveniently had a few -377 Stratocruisers lying around. Enter too Jack Conroy, a former Air Force pilot and visionary who saw an opportunity to be had. Together the two hatched a plan to take the basic -377 design, lengthen it, and then build a massive cargo hold atop the base. As Boeing attests on its own website, the process turned “one of the most elegant airplanes in the sky…[into]…one of the ugliest.”

Two Stratocruisers, former Pan American Airways and BOAC birds, were used to create the very first Guppy. Construction was done by On Mark Engineering, and the airplane was ready to take to the skies by the fall of 1962. Understandably, critics of the airplane thought it would wind up like the Spruce Goose and never fly.

Nicknamed Pregnant Guppy, or the -377PG for short, the airplane lumbered into the air for the first time on September 19th of that year, proving its many critics wrong. The plane was flown by Conroy himself along with famed pilot Clay Lacy.


The dimensions were truly massive for its time. The airplane measured 127 feet long, with a cargo hold just shy of 20 feet across, and a detachable tail section for loading and unloading. Yet despite undertaking NASA contracts one year later in September of 1963 it was already apparent a larger version would be needed.

While the original was built on the back of the Stratocruiser, the newer, larger Guppy was built using its military counterpart, the KC-97 Stratotanker. Yet the KC-97 was not the only airplane the Very Pregnant Guppy, later simply renamed the Supper Guppy, poached parts off of.

The airplane also worked in 707 components, and later versions included parts from the C-130 Hercules, P-3 Orion, and even the original -377PG. Despite being dependent on these pilfered parts and far from clean sheet, the new design managed to be primarily built from scratch.

The Super Guppy was significantly larger than its predecessor. In the final version, the cargo compartment measured 25 feet tall and 25 feet wide. It measured 111 feet long, only ten feet short of the entire length of its predecessor. The detachable tail section for loading and unloading in the -377PG was replaced with the hinged nose section it has today.

The engines were eventually fully upgraded from four Pratt & Whitney 3,500hp R-4360-50 radials to the current 4,680hp Allison 501-D22C turboprops. Improvements were made to the shape of the airframe, namely streamlining, to up performance.


The first of five Super Guppys took off on the last day of August, 1965. Aside from an incident four weeks later in which the force of a high speed dive broke open a hole in the nose that nearly caused the airplane to implode, the airplane went on to have an interesting, though comparatively uneventful, career. For a time the airplanes continued to fulfill the purpose for which they were originally built; hauling parts for NASA’s Apollo space program. As the 1970s progressed and the program wore down, it became clear a new life was needed for the unique airplanes.

Thankfully Airbus came to the rescue in 1972. The European airplane manufacturer, then a lowly upstart, needed an airplane capable of moving A300 jet parts between factories in France, Germany, and the UK. The company not only contracted two of the three existing aircraft but further bought a license to produce two more in the early 1980s.

With KC-97 and -377 parts becoming near to impossible to find, the company wound up having to buy the original Pregnant Guppy and salvage it for parts to complete the last plane. The airplanes enjoyed a healthy career of two decades with Airbus, before they were replaced by the larger and more efficient Beluga jet in the mid-1990s.

Of the five Super Guppies, only one remains airworthy. The original is mothballed at the Pima Air and Space Museum in Arizona. The other three were ferried off to museums in Europe following their tours of duty with Airbus. Of the three, one can be found at the Bruntingthorpe Aerodrome in the UK, while the other two are located outside of the company’s Hamburg and Toulouse factories.


The fifth, and last, Super Guppy to be produced was shipped to the US to fly for NASA in the late 1990s. Registered N941NA, the airplane spent the bulk of its post-Airbus life moving parts for the International Space Station (ISS). While the ISS mission has largely wrapped up, the Guppy continues to haul parts for NASA, just like its older sibling the Pregnant Guppy, to this day.