1931 Curtiss XF9C-1 explored the concept of airship-based aircraft deployment
The Curtiss XF9C-1 is a so-called “parasite fighter,” a small airplane designed to be deployed from a larger aircraft such as an airship or bomber. This factory image shows a prototype XF9C-1 biplane without its “skyhook” launch and recovery system. (Photo from the Paul S. Maynard archive)
The recent headline news of another crash of a U.S. Air Force CV-22 Osprey reminds of the sometimes-daring aircraft prototypes of the 1920s and 1930s. One such example is the Curtiss XF9C-1 “Sparrowhawk.”
In the early 1930s, the United States Navy sought an innovative solution for launching and recovering aircraft from its airships. The answer came from the Curtiss XF9C-1, a lightweight biplane designed to be carried and deployed from the USS Akron and USS Macon airships.
The Sparrowhawk was a revolutionary concept intended to extend helium-inflated airships’ operational range and versatility, turning them into mobile aircraft carriers.
Though technically considered a compact fighter biplane with a pair of machine guns and a 100-pound bomb, the Curtiss XF9C-1 was better at surveillance, and even that was compromised by poor visibility to the ground.
According to Wikipedia, the Curtiss XF9C-1 is an example of a so-called “parasite fighter,” a small airplane designed to be deployed from a larger aircraft such as an airship or bomber.
The Curtiss-Wright Corp. engineered the XF9C-1 to work with a unique trapeze mechanism mounted on the underside of the airship. A so-called “Skyhook” system was affixed to the biplane’s top wing, which would connect with the crossbar of the trapeze.
The F9C-2 Sparrowhawk fighter, piloted by Lieutenant D. Ward Harrigan, USN, was shown hanging from the airship USS Macon’s trapeze. (Navy photo via Wikipedia)
‘The Men on the Flying Trapeze’
Per Wikipedia, the biplane’s hook was engaged on the trapeze inside the airship’s hangar for launching. The trapeze was then lowered clear of the hull into the moving airship’s slipstream and, engine running, the Sparrowhawk would then disengage its hook and fall away from the airship.
For recovery, the biplane would fly underneath its mother ship, beneath the trapeze, climb from below, and hook onto the crossbar. The width of the trapeze crossbar allowed a certain lateral leeway in approach. The biplane’s hook mounting had a guide rail for protection from the turning propeller. Engagement of the hook was automatic on positive contact between the hook and trapeze.
Once the Sparrowhawk was securely caught, it could be hoisted by the trapeze back within the airship’s hull, the engine being stopped as it passed the hangar door.
Although seemingly a tricky maneuver, pilots soon learned the technique, and it was said to be much easier than landing on a moving, pitching, and rolling aircraft carrier.
More than one attempt might have been necessary in gusty conditions before a successful engagement was achieved. Almost inevitably, the pilots soon acquired the epithet “The men on the Flying Trapeze,” and their aircraft were decorated with appropriate unit emblems.
Curtiss F9C-2 Sparrowhawk fighters flying in a V formation, circa 1933-1935. These planes are part of the heavier-than-air group of USS Macon. (U.S. Naval History and Heritage Command Photograph)
Airship Assist
According to Airships.net, the ships were built with hangars, approximately 75 feet long by 60 feet wide by 16 feet tall. The initial hangar design would have the capacity to stow and service up to five aircraft; however, structural rigging limited the actual biplane capacity to three.
With a wingspan of 26 feet and a length of 19 feet, the Sparrowhawk was powered by a Wright R-975-E3 9-cylinder radial engine, generating 420 horsepower. Its top speed reached 176 mph, with a range of 270 miles. The XF9C-1 was armed with two .30 caliber machine guns and carried a 100-pound bomb under its fuselage. The aircraft’s compact design made it well-suited for its role as an airship-based interceptor.
Despite its promising potential, however, the Sparrowhawk’s career was short-lived. The tragic crash of the USS Akron in 1933, along with the subsequent decommissioning of the USS Macon, ended the operational role of the Curtiss XF9C-1.
The lessons learned from this daring experiment contributed to the evolution of naval aviation and the development of more advanced aircraft carriers.
A top view of a plane on the trapeze being lowered from the airship hangar.
CURTISS XF9C-1 SPARROWHAWK SPECIFICATIONS
Role: Airship-based fighter/interceptor
Manufacturer: Curtiss-Wright Corp.
Crew: 1 (pilot)
First flight: Nov. 12, 1931
Wingspan: 26 feet
Length/height: 19 feet/10 feet
Empty weight: 2,205 pounds
Max. takeoff weight: 3,226 pounds
Engine: 420-hp Wright R-975-E3 9-cylinder radial engine
Maximum Speed: 176 mph
Range: 270 miles
Ceiling: 22,500 feet
Armament: 2 .30-caliber Browning machine guns
Payload: 1 100-pound bomb
Sources: Wikipedia; MilitaryFactory.com
Note: This is another image from my dad, Paul Smith Maynard, who worked as an engineer in aviation for four decades. Dad began his career in 1943 after graduating from West Virginia University. He started with Curtiss-Wright Corp., a pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International.
See more of his vintage plane pics here.
