Airplanes and Rockets' history & copyright Google search American Modeler Air Trails American Aircraft Modeler Young Men Hobbies Aviation Flying Aces Saturday Evening Post Boys' Life Hobby Distributors Amateur Astronomy Engines & Motors Balsa Densities Silkspan Covering Comics Electronics My Models Model Aircraft Articles Plans Model Boat Articles Plans Model Car Articles Plans Model Train Articles Plans 1941 Crosley 03CB Radio Model helicopter articles & plans Crosswords Model Rocket Articles Plans Restoration Projects Photos Peanuts Collection Model Aircraft Articles Plans Sitemap Homepage Hints and Kinks Amateur Radio Archives of the homepage R/C Modeler Electronics About Airpleans and Rockest, Disclaimer, Terms of Use Model Topics Please Donate to Airplanes and Rockets Parole Plaza, Annapolis, Maryland Hobby Items for Sale Airplanes and Rockets Hero Graphic
Model Aircraft Museum, AMA - Airplanes and Rockets

RF Cascade Workbook 2018 by RF Cafe

Cafe Press

100-Ton Flying Wing
May 1946 Popular Science

June 1941 Popular Science
June 1941 Science Popular Science - RF Cafe[Table of Contents]

Wax nostalgic over early technology. See articles from Popular Science, published 1872 - 2021. All copyrights are hereby acknowledged.

sink-me

100-Ton Flying Wing

Under construction for three years, the XB-35 was designed so that all external surfaces contribute to lifting it.

Outstrips B-29

By Leon Shloss and Andrew R. Boone

Efforts to make tailless aircraft prac-tical began the year before Orville Wright was born. At least 40 pioneers, of nearly as many nationalities, have contributed to the science. Now an American, John K. Northrop, has done it with the Army's XB-35 bomber.

This plane, weighing 89,000 pounds empty, under overload conditions will lift 60 tons of bombs, gas, crew and cargo. The 209,000-pound gross weight is 78,000 pounds more than that of the Boeing B-29 Superfortress. The boomerang-shaped wing is 4,000 square feet in area, more than double the B-29's; hence the great lifting power. Most parasite drag went out with the fuselage, and higher speed came in. The speed figure is undisclosed, but it is known that the plane is expected to outfly the fastest conventional fighters, which approach 500 m.p.h. Four Pratt & Whitney 3,000-hp. engines turn Hamilton Standard coaxial pusher propellers. Fifteen Flying Wings have been ordered, with jet power in prospect for future models. The plane will be shown about the time this story appears. First flight depends on progress of pilots who are preparing to fly the radical giant. Complicating the problem was the death of the outstanding Flying Wing test pilot, and the short, 5,700-foot runway from which the first take-off must be made.

Artist's conception (above) shows XB-35 in flight over Los Angeles. To the right you see open section of wing that may hold cargo.

Wing slots on the N9M, 60-foot scale-model forerunner of the XB-35, were added to increase stability at low flying speeds. Control is achieved by slots, wing rudder and tabs, plus Northrop "elevons," which function as combined ailerons and elevators.

This pseudo Flying Wing of 1929, with 30-ft., 6 -in. wing span, contributed a lot of data to the plans of the XB·35.

The N9M was the last of four 60-foot scale models used to predetermine the flight characteristics of the XB-35.

Built by the Northrop Aircraft Co., at Inglewood, Calif., of a ware developed aluminum alloy - 75-S - the XB-35 has a theoretical range of 10,000 miles - from New Orleans to Singapore. Everything is carried within the wings including the engines, excepting gun turrets and a pilot-canopy bubble. All external surfaces contribute to lift. "Elevons" installed in the trailing wing edges combine the functions of elevators and ailerons. Landing flaps, trim flaps and rudders are also in the trailing edges. To move the controls the pilot uses a so-called "feel" system coupled to a full hydraulic boost system. The "feel" applies varying pneumatic forces to the control system at different speeds to hold control movements within safety limits.

Further control is achieved by automatically operated long wing slots paralleling the leading wing edge. These slots assure continued smooth laminar airflow at near-stalling speeds.

Militarily, the XB-35 enjoys the unprecedented advantage of comprehensive fire power aft, thus removing the airplane's greatest combat vulnerability - the hard-to-defend tail. It also presents a smaller target-and can carry the atom bomb, a chore performed heretofore only by the B-29.

Other advantages listed by Northrop will apply to cargo as well as fighting editions: Low drag, high lift allowing transport of any weight faster, farther and cheaper; simple construction; more even distribution of weight; spanwise compartments that accommodate rectangular packing cases more neatly and can be loaded or unloaded more quickly and easily than tubular holds.

Several foreign designers have built tailless airplanes that flew well, but they encountered engineering obstacles, which Northrop presumably has whipped. There is a transition phase in take-off and landing during which a tailless plane may be hard to control. The biggest engineering hurdle, however, has been the tendency of tailless planes to flat-spin, followed by inability to nose down in order to recover. Until the wing was made thick enough to enclose engines, crew, payload - everything, in fact - there was little aerodynamic justification for such a plane. And a wing that thick meant a plane far larger than could be economically justified. Military need in World War II for mammoth planes, and the current postwar demand for volume and global air transport, brought about a wing large enough to increase chord (depth of wing) to the point where the nose will go down.

Another shortcoming was the inability of tailless planes to glide to safety in case of engine failure. This was ironed out along with the original problem when, in the '30s, aircraft engines became so dependable that failures became virtually unknown.

A great obstacle to Flying Wing development has been the timidity of industry to delve into types untraditional and therefore hard to sell. It has usually been the unconservative boss of the small shop who has waded into the lists of radical design. That describes 50-year-old Jack Northrop, who has been designing radical airplanes for 30 years. His first model of the Flying Wing, with a wing span of 30 feet, six inches, had twin booms and a tail, and so was not a true Flying Wing. The first true Wing was flown in 1940, utilizing drooped wing-tip controllers, which Northrop proved successful by experimentation with paper models. This plane was built of wood, easily adaptable to changes in design. General H. H. Arnold, later head of the Army Air Forces, saw this plane fly and ordered developmental work begun on a huge Flying Wing bomber from which grew the XB-35.

 

 

Posted

Espresso Engineering Workbook


Academy of Model Aeronautics Government Advocacy Coalition - Airplanes and Rockets

Academy of Model Aeronautics (AMA) - Airplanes and Rockets

Academy of Model Aeronautics

Tower Hobbies logo - Airplanes and Rockets

Tower Hobbies

Horizon Hobby logo - Airplanes and Rockets

Horizon Hobby

Sig Manufacturing - Airplanes and Rockets

Sig Mfg

Brodak Manufacturing - Airplanes and Rockets

Brodak Mfg