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Trivia Testers

What propeller-driven aircraft had a fuselage that was nearly as tall as it was long?

What propeller-driven aircraft had a fuselage that was nearly as tall as it was long?

  1. The McDonnell XF-85 "Goblin"
  2. The Italian Stipa monoplane
  3. The Lockheed-Martin GZ-20 and GZ-22
  4. The Aero Spacelines 377SG

Answer: Before I blurt out the answer, first, an unsolicited word about some technical minutiae: the ducted fan. It offers advantages at both high and low subsonic speeds. Most of us have flown on airliners powered by turbofan engines. Although the lower speed realm for the most part comprises obscure VTOL and air-cushion vehicles, or perhaps the enclosed fenestron tail rotor of some turbine helicopters, it is the lower speeds where the advantages of a ducted fan over a propeller in the open free stream of air are actually the greatest. With a ducted fan, there is no region of reversed flow near the propeller tip, there is a higher net mass flow of air and significantly greater static and low-speed thrust, additional lift force using a properly shaped duct, less propeller tip "buzz" noise, and of course, the opportunity for thrust vectoring. Now we're all familiar with the appearance of a ducted fan turbine, and certainly having jet engines placed inside the main fuselage of jet fighter aircraft, reminiscent of the primitive digestive system of an annelid worm, wherein air is taken in through the front and then expelled straight out of its posterior end at high speed, which draws no second looks. But what about doing that with a reciprocating engine and a propeller?

In the late 1920's the Italian Air Ministry designed an experimental aircraft with a tubular "venturi duct fuselage." Designed by Luigi Stipa, in 1932, Gianni Caproni's company built one. It stood about 11 feet tall, had a length of about 20 feet, and a wingspan of almost 47 feet. It was powered by a 120 h.p. D.H. Gipsy III engine. The top speed was 83 mph, and the lift effect of the tube made the landing speed 42 mph. (Yes, the answer is B.) It might be said to resemble a kind of fascist Gee-Bee racer (although the fuselage width to overall length ratio of the Stipa was actually almost twice that of the Gee Bee). Although the height-to-length ratio for the "Goblin" (choice A) was about the same as the Stipa, it was jet powered. As for the GZ-20 (choice C), it does have quite an impressive girth, yes, but still its stoutness doesn't match these other two. It has a width of some 50 feet, but its length is over 190 feet. Of course, you would expect that of the Goodyear Blimp... As for the SG (or the newer SGT-F) in choice D, that's the Super Guppy. Although it's a zaftig 25 feet wide and the fuselage is 32 feet high, with a length of about 144 feet, it's hardly a competitor.

Unidentified Flying Hubcaps
True or false: The United States military had in its possession, at one time, an actual flying saucer.

Answer: True. Actually, they had two. Notice though, that I didn't say anything about how well they flew. During the middle of the twentieth century, the US military oversaw the development of an extraordinary variety of test aircraft, testing many variations of airframes and means of propulsion. In the early 1950s, a Canadian firm named Avro Aircraft—the parent company was A.V. Roe—began developing a unique, supersonic VTOL fighter-bomber aircraft intended to cruise at low altitudes on a cushion of air and accelerate to high speeds at high altitudes. In 1958, the U.S. Army and Air Force took control of the project, naming the vehicle "Avrocar" and designated it the VZ-9AV ('VZ,' experimental vertical, ninth concept proposal, and Avro). The Army wanted a rugged subsonic, all-terrain vehicle: in short, a flying jeep. The Air Force wanted something that could hover beneath enemy radar and then rocket into the stratosphere at supersonic speeds. The entire aircraft was a circular wing not quite 20 feet wide, three feet thick, and shaped exactly like a flying saucer. The aircraft was powered by three gas-turbine engines which drove a five-foot "turborotor" mounted in the center of the vehicle, with thrust directed through nozzles and peripheral jets for lift and control forces.

A scale model of the aircraft sent to Wright Field revealed a serious problem: at altitudes of more than a few feet the cushion of air supporting the aircraft became unstable, causing uncontrollable pitch oscillations, coupled with heavy roll. (Avro called it "hubcapping".) The problem could be solved but it would probably never fly supersonic. Despite this, the US hoped that at least the Army's requirements could be met. In the fall of 1959 the first completed prototype rolled out onto Avro's taxiway near Toronto. The Avrocar first flew with a pilot on Dec. 5, 1959. The VZ-9 reached a maximum speed of 35 mph, and its service ceiling turned out to be all of about six feet; all attempts to eliminate hubcapping failed. A second prototype was shipped to NASA Ames in California, for wind tunnel tests. Exploring the other end of the flight envelope, they discovered the Avro had insufficient control for high- speed flight and was aerodynamically unstable. Adding a conventional empennage did not improve things. The technical problems seemed insurmountable and the U. S. Air Force terminated the program in December 1961 due to limited flight success, mechanical problems, and possible disenchantment over the flying saucer design. The Avrocar was the last aviation program of Avro Canada, and the parent company ceased to exist by May 1962. Two examples of the saucer ship still exist, though; one is at the US Army Transportation Museum at Fort Eustis, Virginia, the other is at the Smithsonian's Garber restoration facility.

Talk About Inverted!
True or False: An airplane can be made to land and take off while inverted.

Answer: Okay, I'll bet you're wondering how I'm going to weasel out of this one. Well, this picture ought to pretty much give it away. Nicknamed "Double Take", this Pitts S-2B was owned by one Craig Bryant Hosking of California, who is a Hollywood aerobatic and stunt pilot (and a recipient of the Art Scholl Memorial Award). His name is in the credits for Space Cowboys, Pearl Harbor, and The Kid, among others.) Craig first demonstrated inverted landings in the mid-1980s.

He selected the Pitts S-2B for its powerful engine, its ability to maneuver through most aerobatic routines, its durable airframe, and outstanding performance. Modifications were planned and drawn up with the help of a fellow aerobatic pilot, aircraft builder, and welder. Aside from having to attain a new perspective on landing an airplane, an obvious requirement to attach a second set of landing gear on the top wing, a special retention system that allows him to be lowered from the cockpit while inverted on the ground, others included ensuring a second brake system, and keeping the cylinders free from oil when the plane was parked inverted.

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