3/6/19 Seminar 4 Early Space Age Launch Vehicle Dynamics FRS 148, Princeton University Robert Stengel • Political Rains and First Fruit: The Cold War and Sputnik America Before Sputnik § Bashful Behemoth: Technology, the State, & the Birth of Deterrence § While Waiting for Technocracy: The ICBM & the First American Space Program Launch Vehicle Flight Dynamics …the Heavens and the Earth, Ch 2 to 4 Understanding Space, Sec 9.1, 14.1 (pp. 535-542), 14.3 Copyright 2019 by Robert Stengel. All rights reserved. For educational use only. 1 http://www.princeton.edu/~stengel/FRS.html Political Rains and First Fruit: The Cold War and Sputnik 2 1 3/6/19 German Vengeance (Aggregate) Weapons A-3 A-4 (V-2) A-4b V-1 “Buzz Bomb http://en.wikipedia.org/w iki/Aggregate_(rocket_family) 3 V-2 (A-4) Rocket • Gyro Control • Thrust and aero steering • 6,084 built during WWII • 1000+ test flights • 3,225 launched in combat 4 2 3/6/19 Peenemünde, Mittelwerk, Wernher von Braun, and the German Rocket Team Helmut Gröttrup 5 German Vengeance Weapons and Space Launch Vehicles [never built] A-11 A-12 A-12 6 3 3/6/19 Sänger “Antipodal” Bomber Concept (1935-1941) Dr. Eugen Sänger (1905-1964), Austrian designer Sub-Orbital “Skip” Trajectory http://www.luft46.com/misc/sanger.html 7 Nuclear Weapons and the Balance of Power Trinity Test Trinity Test Hiroshima Explosion “Enola Gay” B-29 “Fat Man” “Little Boy” 8 4 3/6/19 Balance of Power in Europe Stalin’s 5-Yr Plan 9 Post-WWII Soviet Rocket Development R-7 G Series: Principally interned German Engineers R Series: Principally Russian Engineers 10 5 3/6/19 Sputnik 1 and the R-7 (October 4, 1957) R-7 (Semyorka) launch Sergei Korolev vehicle (ICBM) (1907-1966) Sputnik 1 11 Eight Characteristics of Soviet R&D 1) Need to borrow foreign 5) Scarcity of skilled technology and desire to workers, need to keep foster national creativity unskilled workers occupied 2) Lack of competitive stimulus 6) Tradition of pure and planning system that research, priority to inhibited innovation by science not technology production managers 7) Organizational distance 3) Inhibitions due to terror between R&D and (risk of failure) production 4) Te nsio ns between 8) Less concern for professionalization of R&D economics than technical and adherence to the party performance line 12 6 3/6/19 Commonalities Between Post-War US and USSR § Continental superstates § Born of revolutions inspired by ideology of progress § Faith in the works of man § Patriotism rooted in § common ideas, values, and experience rather than § tradition, religion, or ethnicity … § or not? § Came of age internationally during the world wars and prevailed because of § geographical expanse § remoteness § unprecedented mobilization of technical resources § Emerged from isolationism to become superpowers 13 America Before Sputnik Bashful Behemoth: Technology, the State, and the Birth of Deterrence 14 7 3/6/19 Buildup of Federal Support for R&D § Civil War spawned National Academy of Sciences, 1863 § American pattern § Diffuse entities for research § Army and navy arsenals the exception American assembly lines § Lack of European "command technology” § NACA established in 1915 [by President Woodrow Wilson] at Langley Research Center § 1920s § Veblen lobbies for federal support of R&D § Hoover lobbies for federal support of R&D § Great Depression, 1929 to 1939 15 Robert Goddard (1882-1945) • Physics Professor, Clark University, Worcester MA • “A Method of Reaching Extreme Altitudes”, 1919 • New York Timess editorial comment(1920): "after the rocket quits our air … it will neither be accelerated nor maintained by the explosion of the charges it then might have left.” “To claim that it would be is to deny a fundamental law of dynamics” (The NYT Editors) expressed disbelief that Professor Goddard actually "does not know of the relation of action to reaction, and the need to have something better than a vacuum against which to react.” New York Times regretted its error on July 17, 1969, the day after Apollo 11 was launched to the Moon 16 8 3/6/19 Robert Goddards Rockets, 1926-1941 17 US Rocket R&D in the 1930s American Rocket Society Guggenheim Aeronautical Laboratory, CIT Reaction Motors, Inc. 18 9 3/6/19 US R&D Through 1948 § 1941: R&D turnaround § Military needs § Federally funded labs § "Arsenal of democracy" § Vannevar Bush: Civilian extension of Office of Scientific Research and Development § Henry Stimson and James Forrestal (Princeton, Forrestal campus), Research Board for National Security § R&D without politics – good idea? § 1944: Henry Smyth (Princeton) report on peaceful use of atomic energy § 1945: Atomic Energy Commission § 1946: Canadians crack Russian atomic spy ring § 1948: Military R&D: 62% of federal total 19 Post-War Developments § 1943: Marshall: Deterrence, long-range bomber atomic strike capability § 1947: George Kennan's Foreign Affairs article, "The Sources of Soviet Conduct”: containment § Truman's Board of Budget director: James Webb § 1945-49: US sought a counterweight to Soviet's conventional military might: Strategic Air Command § Cruise missiles (e.g., Northrop Snark) vs ballistic missiles § USAF: responsibility for strategic ballistic missiles § Army: responsibility for tactical ballistic missiles B-52 Snark B-47 20 10 3/6/19 Significance of Map Projections Cylindrical Projection: Mercator Map Azimuthal Projection: Polar Map 21 Project Bumper (V-2/WAC Corporal) 1948-1950 •White Sands, NM •Cape Canaveral, FL nd •2 stages 2 •8 flights, 4 failures Stage •Engineering development •High-altitude photography •Atmospheric temperature profile •Cosmic radiation V-2 22 11 3/6/19 Dawn of the Missile Age, 1956 Hydrogen Bomb First Test First Deliverable Device Tested USSR Aug 1953 Nov 1955 US Nov 1952 May 1956 Contest for influence in the “3rd World” 23 While Waiting for Technocracy: The ICBM and the First American Space Program 24 12 3/6/19 Precursors to US ICBMs, 1946-1948 § Convair Project MX-774 § Swiveling engines § Separable nose cone § Outer skin was propellant-tank wall § RAND study of satellite launch Convair RAND World- MX-774 circling Spaceship 25 Post-World War II Science Fact and Fiction Catalyzed human imagination Chesley Bonestell (1888-1986) Willy Ley (1906-1969) Wernher von Braun (1912-1977)26 13 3/6/19 Hydrogen Bombs, 1952-1953 Soviet Joe-4, 1953 US Ivy MIKE, 1952 27 Military-Industrial Complex § UN debates § Baruch Plan (international control) § Gromyko's response (unilateral US disarmament) § How would ban on nuclear weapons have affected military power balance? § Roles and missions contested within American military -- inseparable from the Cold War (Daniel Yergin) § Navy, ground power, air power, ... § Tradition, size, power, sick aviation industry, conversion of factories § Importance of aviation industry to US security § Truman's recognition (1946) § Continued growth of aviation R&D, including rockets and missiles 28 14 3/6/19 Resistance to ICBMs and Satellites § Invasion of South Korea by North Korea, June 1950 § Bureaucratic resistance to ICBMs § Guidance systems, MIT Instrumentation Lab § Blunt body re-entry vehicle proposed, NACA Langley MiDAS § Reports of Soviet rocketry supported need for a crash ICBM program § Atlas given highest priority, June 1954 § RAND studied utility of satellites for strategic and meteorological reconnaissance,1950 § Political problems with over-flight, even in orbit. § How would the Soviets respond? § This worried Eisenhower § Policy must be charted in advance § WS-117L: Missile Defense Alert System (MiDAS) 29 Launch Vehicle Flight Dynamics 30 15 3/6/19 Launch Phases and Loading Issues-1 • Liftoff – Reverberation from the ground – Random vibrations – Thrust transients • Winds and Transonic Aerodynamics – High-altitude jet stream – Buffeting • Staging – High sustained acceleration – Thrust transients 31 Launch Phases and Loading Issues-2 • Heat shield separation – Mechanical and pyrotechnic transients • Spin stabilization – Tangential and centripetal acceleration – Steady-state rotation • Separation – Pyrotechnic transients 32 16 3/6/19 Equations of Motion for a Point Mass ⎡ x˙ ⎤ ⎡v x⎤ dr ⎢ ⎥ ⎢ ⎥ = r˙ = v = y˙ = v dt ⎢ ⎥ ⎢ y⎥ ⎣⎢ z˙ ⎦⎥ ⎣⎢v z ⎦⎥ ⎡1 /m 0 0 ⎤⎡ f x⎤ dv 1 ⎢ ⎥⎢ ⎥ = v˙ = F = 0 1/m 0 f dt m ⎢ ⎥⎢ y⎥ ⎣⎢ 0 0 1/m⎦⎥⎣⎢ f z⎦⎥ 33 Equations of Motion for a Point Mass Velocity and position dynamics expressed in a single equation ⎡ x ⎤ ⎢ ⎥ ⎢ y ⎥ dx(t) ⎡r ⎤ ⎢ z ⎥ x˙ (t) f[x(t),F] x ≡ ⎢ ⎥ = ⎢ ⎥ = = v v dt ⎣ ⎦ ⎢ x⎥ ⎢v y⎥ ⎢ ⎥ ⎣v z ⎦ 34 17 3/6/19 Combined Equations of Motion for a Point Mass ⎡ x˙ ⎤ ⎡ vx ⎤ ⎡0 0 0 1 0 0⎤⎡ x ⎤ ⎡ 0 0 0 ⎤ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥⎢ ⎥ ⎢ ⎥ y˙ v 0 0 0 0 1 0 y 0 0 0 ⎢ ⎥ ⎢ y ⎥ ⎢ ⎥⎢ ⎥ ⎢ ⎥ ⎡ f x⎤ ⎢ z˙ ⎥ ⎢ vz ⎥ ⎢0 0 0 0 0 1⎥⎢ z ⎥ ⎢ 0 0 0 ⎥⎢ ⎥ ⎢ ⎥ = ⎢ ⎥ = ⎢ ⎥ + f y v˙ f /m ⎢0 0 0 0 0 0⎥ v ⎢1 /m 0 0 ⎥⎢ ⎥ ⎢ x⎥ ⎢ x ⎥ ⎢ ⎥⎢ x⎥ ⎢ ⎥⎢ f ⎥ ⎣ z⎦I ⎢v ˙ y⎥ ⎢ f y /m⎥ ⎢0 0 0 0 0 0⎥⎢ v y⎥ ⎢ 0 1/m 0 ⎥ ⎢v ˙ ⎥ ⎢ f /m⎥ ⎢ ⎥⎢ v ⎥ ⎢ ⎥ ⎣ z ⎦I ⎣ z ⎦I ⎣0 0 0 0 0 0⎦⎣ z⎦I ⎣ 0 0 1/m⎦ ⎡ f x⎤ With ⎢ ⎥ F = f = F + F + F I ⎢ y⎥ [ gravity aerodynamics thrust ]I ⎢ f ⎥ ⎣ z⎦I 35 Math Models of Gravity • Flat-earth approximation ⎡ 0 ⎤ – g is gravitational ⎢ ⎥ 2 mg m 0 ; g 9.807 m /s acceleration f = ⎢ ⎥ o = – mg is gravitational force ⎣⎢g o⎦⎥ – Independent of position ⎡g x⎤ • Round, rotating earth ⎢ ⎥ g = g = g [non − rotating frame] – Inverse-square gravitation r ⎢ y⎥ gravity ⎢ g ⎥ – Centripetal acceleration ⎣ z ⎦ – Non-linear function of gr = ggravity + grotation [rotating frame] position ⎡ x⎤ ⎡ x⎤ 5 3 2 −µ ⎢ ⎥ 2 ⎢ ⎥ 2 2 2 1/ 2 – μ = 3.986 x 10 km /s = y − Ω y ; r = x + y + z 3 ⎢ ⎥ ⎢ ⎥ [ ] –5 r – Ω = 7.29 x 10 rad/s ⎣⎢ z⎦⎥ ⎣⎢0 ⎦⎥ 36