From today’s perspective, when in-flight refueling has long been routine, the early attempts to get airplanes to fly farther than their own gas tanks would take them seem almost comically desperate. The piggyback rides or kangaroo pouch-like transport flights, during which a mothership drags along a smaller parasite airplane, have the daffy quality of Buster Keaton silent-action gags—and a similar success rate. The surprise is that any carrier-parasite pairs were successful. Yet some of these “composite aircraft” were ingenious solutions to the problem of getting a payload to a faraway or otherwise difficult-to-reach destination.
As with all experimental aviation, the most memorable parasite airplanes weren’t necessarily the most successful. Often, the pair did not strike the right balance; others became obsolete before full testing was finished. Only a few, like the Maia and Mercury shown here (details below) had long, storied relationships. See the gallery above for more of our favorites.
Pictured above: The mailplane Mercury hops aboard a seaplane.
Hitchhiker: Short S.20 Mercury
Mothership: Short S.21 Maia
It’s Wednesday, July 20, 1938, and a short but calculated conversation was taking place over Foynes, Ireland.
“Ready!” said Captain Donald C.T. Bennett, seated in a Short S.20 Mercury mailplane.
“OK and good luck,” replied A.S. Wilcockson, pilot of the Short S.21 Maia seaplane.
Bennett counted to three, then yelled, “Go!” Both men pulled a release lever, and Bennett was on his way toward Canada.
The next day, the front page of the New York Times bore the headline: “ ‘Pickaback’ Plane Spans Atlantic After Take-Off From Bigger Craft.”
It was a monumental day for aviation: The Mercury had become the first heavier-than-air commercial aircraft to cross the ocean, and in record time. It landed in Montreal 20 hours, 20 minutes after takeoff. Next stop: New York City.
While many parasite airplanes were attached to their hosts because they couldn’t travel far, the 51-foot-long Short S.20 could go the distance—it just couldn’t get off the ground. Carrying enough fuel to make a transatlantic flight (in addition to the mail) made it too heavy to achieve takeoff.
The Mercury and the Maia were developed together to solve this problem. “If an aircraft didn’t actually need to take off from the water but was ‘launched’ at flying speed, it might carry enough fuel to cross the Atlantic as well as a useful payload of mail,” says British aviation enthusiast Don Goodsell. With Maia’s assist, the letter carrier could put on nearly 10,000 additional pounds and still make it across an ocean.
On its first transatlantic attempt, all eight engines from both airplanes were needed for takeoff. The Maia used Bristol radial engines, but “the Mercury was a new design, with twin streamlined floats and four Napier Rapier H-configuration engines, a type designed by Major [Frank] Halford, who eventually headed the de Havilland Engine Company,” says Goodsell.
A few months later, the Maia air-launched the Mercury on a 6,045-mile journey from Scotland to South Africa—a record distance for seaplanes.
Testing stopped as World War II loomed, and soon both aircraft met untimely ends: The Mercury was given to Allied Dutch pilots for a year, then returned to the Short company and dismantled in 1941; the Maia was destroyed by enemy fire the same year.
Lynn Keillor is a Minneapolis-based freelance writer.
All Speed, No Endurance
Hitchhiker: Bristol Scout C
Mothership: Felixstowe Porte Baby flying boat
The single-seat Bristol Scout C was a screamer. At the outset of World War I, it was one of the fastest airplanes available, reaching a top speed of nearly 100 mph. The Scout’s light weight and agility made it an especially effective fighter. It had one frustrating fault: the underpowered 80-horsepower Le Rhône engine could last only about two hours in the air without maintenance.
As an experiment, British aviation entrepreneurs mated the Scout with an oversized hulk of an airplane called the Felixstowe Porte Baby. The idea to use a longer-range aircraft (the Porte Baby performed oversea operations between England and the rest of Europe, but its top speed was a plodding 78 mph) as a host for a speedy, shorter-range one was a first in aviation.
In the spring of 1916, in the county of Essex, England, a Scout was loaded onto the upper wings of the Porte Baby. The smaller airplane’s fuselage rested flat on the wing, with its wheels hanging over the front edge, propped up by crutches braced on the Porte Baby’s central engine. The Scout pilot controlled the quick-release mechanism that held its tail.
The airplanes took off with designer Commander John C. Porte piloting his eponymous mothership and Flight Sub-Lieutenant M.J. Day in the Scout. At 1,000 feet, Day fired up the Scout engine, released the aircraft, and flew away. If successful, the little fighter could have hitched a ride to protect the slower, more vulnerable Porte Baby on reconnaissance missions in which it might encounter enemy fire.
For unknown reasons, the Scout–Porte Baby pairing was flown only once, but the first host-parasite mission launched an era of experimentation that continues to this day.