Project Terminated

Project Terminated

Project Terminated: Famous Military Aircraft Cancellations of the Cold War Burt Dicht [email protected] [email protected] Disclaimer The material represented in this presentation is derived the book Project Terminated by Erik Simonsen and from the experiences and knowledge of Burt Dicht. This presentation is not be used for any commercial purposes. This presentation is intended for educational and entertainment purposes only 2 Aircraft Legacies “Which aircraft did you work on mom/dad?” 3 Only A Few Make It • Since the inception of flight aircraft designers have proposed thousands of aircraft concepts • Only a small percentage make it off the drawing board (computer screen) and are actually developed into prototypes • And an even smaller number make it to production 4 Project Terminated • Aviation historians like to ask questions about the aircraft that never made it all the way – What were the issues surrounding their cancellations? – Were they technically sound designs? – What role did politics play? – Were there other external forces involved that were beyond the control of the designers and the company? • This presentation will attempt to answer those questions by highlighting several famous aircraft that were cancelled and featured in a recent book, Project Terminated by Erik Simonsen 5 Northrop YB-49 Flying Wing 6 Jack Northrop • Self-taught aerodynamicist • In 1923 draftsman for Douglas Aircraft – Designed fuel tanks for “Round the World Cruisers” • In 1927 joined Lockheed – Helped design the Vega • In 1929 created Northrop Aircraft first in association with Boeing, than Douglas • In 1940 formed an independent Northrop Aircraft in Hawthorne, CA 7 Experimenting With Flying Wings N-9M Flying Wing (1942) 1/3 scale prototype proposed flying wing N-1M Flying Jeep Wing (1939) Northrop experimented with improving aerodynamic performance . By creating a clean all wing airplane X-4 Bantam (Tailless Experimental -1946) 8 Benefits of a Flying Wing • Low-Drag and High-Lift – transport a payload 25% faster and further than conventional design • Simplicity of fabrication – lower costs • More uniform distribution of weight – simple structural design • Ease of loading and unloading – payload placed in span-wise compartments • Smaller profile target 9 The XB-35 • Origins in 1941 – what if England fell . Loss of operating bases • Needed a bomber that could carry a payload of 10,000 lbs. for 10,000 miles • Won a contract to develop 2 aircraft powered by 4 pusher counter-rotating engines • Work started in 1943 and first flight 25 June 1946 • With jet age advancing, Northrop recommended a switch to 8 Allison J35 turbo-jet engines • Three XB-35s flew before the conversion was made • Aircraft plagued by engine problems during the test phase • Had some stability and flight control issues 10 The YB-49 – Technology • YB-49 made it’s first flight out of Hawthorne Air Field on 21 October 1947 • YB-49 converted from a structure designed for piston engines – Coupled with stability problems and increased speed made for a difficult flight test program • Honeywell developed a yaw stabilization system that improved the stability – Still impacted its effectiveness as a bomber • Testing proved out the YB-49’s speed, range and that it was hard to pick-up on radar • 5 June 1948 a YB-49 crashes killing a crew of 5 (Glenn Edwards) • Air Force decides to purchase 30 RB-49As as flying wing reconnaissance aircraft 11 Cancellation • On 9 Feb 1949 a YB-49A flew 2,258 miles non-stop from Muroc AFB (now EAFB) to Andrews AFB, Maryland in 4 hours and 20 minutes (511 MPH average speed) • President Truman toured the aircraft and suggested it be flown down Pennsylvania Ave. for all to see • On 28 October 1949 the USAF cancels the program and ordered all of the XB-35s and YB-49s scrapped • How did the flying wing go from presidential praise to cancellation in just 8 months? 12 Cancellation Theory • Air Force Secretary Stuart Symington pushing for aircraft company consolidation • Wanted Northrop to merge with Convair • Northrop refused the merger because the conditions were unfavorable • Was that enough to spur the cancellation? • Why were all of the existing flying wings scrapped? • Jack Northrop remained silent at the time because he didn’t want to jeopardize future contracts • In 1979, Northrop said in an interview that he had been in meetings with Symington and the CEO of Convair and he was under enormous pressure to merge . He refused and several days later the flying wing was cancelled 13 Legacy • The Flying Wings were ahead of their time, before the advent of digital flight control systems • But it is possible had they be allowed to continue, great advances might have been made in aerodynamics • And technology did catch up and in an unexpected technical advance, the flying wing paved the way for stealth technology • Its legacy lived on with the B-2 stealth bomber, a true flying wing • And today, Boeing and other aircraft companies are exploring the use of flying wings in commercial aircraft 14 YB-49 – B-2 Comparison Designation YB-49 B-2 Manufacturer Northrop Northrop Grumman Service Year 1947 1997 Length 52.49 ft. 69 ft. Width 171.92 ft. 172.01 ft. Height 20.34 ft. 16.99 ft. Takeoff Weight 194,007 lbs. 336,503 lbs. Range 9,992 miles 7,248 miles Max Speed 493 mph 569 mph Power-plant 8 x Allison / General Electric J35- 4 x General Electric F118-GE-110 A-5 turbojets, 4,000 lbs. each. turbofans, 17,300 lbs. each 15 Flying Wing Drops A-Bomb on Martians The bomb was dropped from a flying From the film “War of the Worlds” wing aircraft (Paramount Pictures – 1953) 16 North American Aviation XB-70 Valkyrie 17 North America Aviation – Advances in High Speed Flight • On 1 June 1957, NAA awarded a contract to develop Weapon System 202A, which would later be called the F-108 • The F-108 was to be a sleek interceptor, designed to cruise at Mach 3 at altitudes above 75,000 feet and reach up to 100,000 feet • At the time NAA was also working on the X-15 Rocket Plane, designed to fly at Mach 6 up to 300,000 feet • NAA was at the pinnacle of aerospace technology development at the time 18 The Mach 3 Bomber • General Curtis LeMay, the SAC Commander wanted a nuclear powered bomber - 1955 • That proved to be impractical from a technology standpoint, but paved the way for a high-speed, high altitude bomber • NAA was awarded the contract to develop Weapon System 110A, later called the XB-70 Valkyrie on 23 December 1957 • Conceived as a nuclear-armed deep- penetration strategic bomber, the Valkyrie was a large six-engine aircraft able to fly Mach 3+ at an altitude of 70,000+ feet • It was designed to avoid interceptors, the only effective anti-bomber weapon at the time. 19 XB-70 Compression Lift • Compression Lift used the shockwave generated off the nose or other sharp points on the aircraft as a source of high-pressure air • By carefully positioning the wing in relation to the shock, the shock's high pressure could be captured on the bottom of the wing and generate additional lift • To take maximum advantage of this effect, they redesigned the underside of the aircraft to feature a large triangular intake area far forward of the engines, better positioning the shock in relation to the wing • Folding wing-tips were added to trap the shock wave under the wing • Compression Lift improved the lift to drag ratio by 30% 20 Technology • Cruising at Mach 3+ required great advances in technology • The aircraft was designed out of a new stainless steel honeycomb and titanium structure to withstand the 650 degree temperatures produced from the aerodynamic friction • Specially developed ejection capsules to ensure the crew would survive (zero to 90,000 feet and 100 to 2100 mph) • Variable geometry inlets to manage the shock waves in the ducts and to position the shock waves created at supersonic speed to enter the engines at subsonic speeds • Fuel capacity was 47,000 gallons and used a special JP-6 Kerosene blend • Six Pack – used 6 General Electric YJ93-GE-3 Turbo-jet afterburning engines – Designed for maximum performance at Mach 3 at 65,000 feet – 30,000 lbs of thrust – but true number was classified 21 Politics versus Technology • B-70 program under development as change from Eisenhower to Kennedy Administration • Robert McNamara becomes Secretary of Defense (Ran Ford Motor Company, but had no experience with aerospace) – Had concern over the costs and viability of long range bombers – In a short time he was making highly technical and complex national security decisions by himself with little input • McNamara reduced number of prototypes to be built to 3 (Only two were built) . And he downgraded program - no operational B-70s were to be tested – Prototypes flown with on 2 crew members, no offensive or defensive systems 22 U-2 Impact • On 1 May 1960, a CIA U-2 Reconnaissance aircraft piloted by Francis Gary Powers was shot down over the Soviet Union • The U-2 was a subsonic high altitude aircraft operating at 70,000 feet • The Soviets used a SA-2 Surface-to-Air Missile • The shoot down of the U-2 would accelerate the demise of the B-70 • By some, high altitude penetration of Soviet airspace was deemed vulnerable because of this one event – The Soviets fired 14 missiles, plus they knew the basic flight plan • The SR-71 (Mach 3+, 80,000 feet+) had more than 800 missiles fired at it and none was ever lost to hostile fire 23 Cancellation • The first XB-70 flew on 21 Sept 1964 and the second on 17 July 1965 • By the end of 1965, both aircraft had flown sustained Mach 3 speeds • McNamara favored ICBM development, was never a fan of strategic bombers and in may cases misspoke about capabilities of the B-70 • The second XB-70 was lost in a tragic accident with an NF-104 in 1966 • By that point the program was cancelled • The remaining XB-70 was turned over to NASA to conduct research on the SST .

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