1. Rocket Science Early Developments & Future Systems by Joseph A. Castellano, Ph.D. RESEED Silicon Valley

2. Outline  Rocket Types  The Minuteman ICBM Program  Rocket Fuel Research at Thiokol Chemical Company in the 1960s  Future Rocket Propulsion Systems

3. Types of Rocket Engines 1.Liquid-Fueled Engines that use “Cryogenic” liquid oxidizers such as Liquid Oxygen (LOX). liquid oxidizers such as Liquid Oxygen (LOX). They may also use a Cryogenic fuel such as They may also use a Cryogenic fuel such as liquid hydrogen (LH 2 ). liquid hydrogen (LH 2 ). 2.“Reaction Motors” that use oxidizers and fuels that are liquid above 0 o C. are liquid above 0 o C. 3.Solid-Fueled Engines that use solid oxidizers and fuels mixed together. fuels mixed together.

4. Features of Liquid-Fueled Rockets  Uses liquid oxygen as the oxidizer – requires low temperature storage and extensive preparation low temperature storage and extensive preparation before launch before launch  Fuel can be liquid hydrogen, which requires low temperature storage, or kerosene which does not temperature storage, or kerosene which does not  Liquids are fed into combustion chamber and ignited with electrical spark electrical spark  Engine can be turned OFF by shutting down the supply of liquids supply of liquids

5. Liquid-Fueled Rocket Engine Fuel OxidizerPumps ThroatNozzle CombustionChamberCombustionProducts

6. Features of Liquid-Fueled “Reaction Motor” Type Rockets  Uses liquid oxidizer that does not require low temperature storage – examples: Nitric Acid or low temperature storage – examples: Nitric Acid or N 2 O 4 (nitrogen tetroxide) N 2 O 4 (nitrogen tetroxide)  Fuel can be dimethyl hydrazine or aniline, which do not require low temperature storage. require low temperature storage.  Liquids are fed into combustion chamber where they react instantly to produce combustion. instantly to produce combustion.  Engine can be turned OFF by shutting down the supply of liquids supply of liquids  Rocket can be stored indefinitely and is ready to go at a moment’s notice moment’s notice

7. Liquid-fueled Rockets Left: “Bullpup” engines on the assembly line at Thiokol. These engines used nitric acid for the oxidizer and aniline for the fuel. Right: Air-to-ground missiles used in the Vietnam War were powered by Bullpup engines.

8. Liquid-fueled Rocket Russian rocket on display at a parade in Moscow’s Red Square in November 1957.

9. Liquid-fueled Rockets The USA’s Saturn V rocket on display at the Kennedy Space Center in Florida.

10. Liquid-fueled Rocket Belt This reaction motor uses a catalyst to decompose 90% hydrogen peroxide into a hot gas mixture (O 2 + H 2 O) at high pressure to produce the thrust.

11. Features of Solid-Fueled Rockets  Fuel and oxidizer are solids mixed together with a polymer “binder,” cast into the shape of the rocket’s body polymer “binder,” cast into the shape of the rocket’s body and enclosed in its casing and enclosed in its casing  Electrically ignited near the nose of the rocket  Fuel burns from top to bottom, and from the center outwards until all the fuel is consumed until all the fuel is consumed  Once ignition begins, engine cannot be turned OFF  Rocket can be stored indefinitely and is ready to go at a moment’s notice moment’s notice

12. Solid-Fueled Rocket Engine Igniter Solid Fuel/Oxidizer Mixture Flame Front Throat Nozzle BurnedPropellant CombustionChamber

13. Solid & Liquid Rocket Engines Combined Space Shuttle Launch Solid Rocket Boosters Liquid Rocket Engine Liquid Hydrogen Tank

14. Solid-fueled Rockets Mass: 36,030 kg Length: 18 m Width: 1.7 m Speed: 24,000 km/hr Altitude: 1,120 km Range: 9,600 km Minuteman III Intercontinental Ballistic Missile (ICBM)

15. Minuteman III Construction Nose Cone Guidance System Reentry Vehicle w/ Payload Post-Boost Vehicle Engine Body Section 3 Body Section 2 Body Section 1 Aerojet/Thiokol Stage 3 Engine 33,800 lbs. thrust Aerojet Stage 2 Engine 60,625 lbs. thrust Thiokol Stage 1 Engine 202,600 lbs. thrust Cable Support

16. Minuteman III Missile Components Stage 1 Nozzle Assembly Stage 1 Solid Propellant Core

17. Minuteman III Stage 2 Engine

18. Minuteman III Missile in Underground Launch Silo

19. Minuteman III Missile Launched from Silo

20. Minuteman III Launch Path 1 - Silo launch 2 - First stage separates (60 sec.) 3 - Second stage ignites (120 sec.) 4 - Post-boost vehicle separates (180 sec.) 5 – PBV re-enters atmosphere 6 – Multiple warheads released 7 – Warheads armed 8 – Warheads strike targets

21. Rocket Fuel Research during the “Cold War”  Soviet Union: Research mostly in liquid fuels Research mostly in liquid fuels and oxidizers, but secret research in solid fuels and oxidizers, but secret research in solid fuels for military ICBMs.  U.S.A.: Intense secret research to find better solid oxidizers Intense secret research to find better solid oxidizers and fuels for military ICBMs. and fuels for military ICBMs. Each side spied on the other to find the nature of the other’s secret research. the nature of the other’s secret research.

22. Photo of Laboratory and Manufacturing Plant in 1969

23. U.S. Secret Rocket Fuel Research at Thiokol Chemical Company in the 1960s  Experimented with exotic gases such as: Perfluoroguanidine(PFG) Tetrafluorohydrazine FN=C-NF 2 NF 2 NF 2 N2F4N2F4N2F4N2F4 HNF 2 Difluoramine

24. U.S. Secret Rocket Fuel Research at Thiokol Chemical Company  Chemical reactions of N 2 F 4 with hydrocarbons: CH 3 -CH=CH-CH 3 + N 2 F 4 CH 3 -CH=CH-CH 3 + N 2 F 4 2-Butene 2-Butene CH 3 -CH-CH-CH 3 CH 3 -CH-CH-CH 3 NF 2 NF 2 NF 2 NF 2 “Bis” Difluoramino Compound with a Vicinal structure with a Vicinal structure Tetrafluorohydrazine

25. U.S. Secret Rocket Fuel Research at Thiokol Chemical Company  Chemical reactions of HNF 2 with ketones: O CH 3 -CH 2 -C-CH 3 + HNF 2 CH 3 -CH 2 -C-CH 3 + HNF 2 2-Butanone 2-Butanone NF 2 NF 2 CH 3 -CH 2 -C-CH 3 CH 3 -CH 2 -C-CH 3 NF 2 NF 2 “Bis” Difluoramino Compound “Bis” Difluoramino Compound with a Geminal structure with a Geminal structure Difluoramine

26. U.S. Secret Rocket Fuel Research at Thiokol Chemical Company  Chemical reactions of perfluoroguanidine with alcohols led to compounds with with alcohols led to compounds with three NF 2 groups on one carbon atom three NF 2 groups on one carbon atom  These materials were powerful oxidizers, but highly sensitive to shock and could but highly sensitive to shock and could explode easily, so it was necessary to explode easily, so it was necessary to work in a remote laboratory behind a work in a remote laboratory behind a thick plastic shield. thick plastic shield.

27. Remote Barricade Laboratory Thiokol Chemical Company - 1964

28. Remote Barricade Lab Vacuum Rack System 1.Insulated steel wall 2.Blow-out roof 3.Thermostat 4.Electrical heaters 5. PFG cylinder 6. Storage flasks 7. Liquid N 2 traps 8. Remote-control jacks 9. Teflon valve 10. Thick glass reactor 11. Magnetic stirrer 12. Tubes for PFG 13. To vacuum pump

29. + + n-Butanol Perfluoroguanidine Intermediate Product Powerful “Tris” Oxidizer Hydrofluoric Acid CH 3 CH 2 CH 2 CH 2 OH FN=C-NF 2 NF 2 NF 2 CH 3 CH 2 CH 2 CH 2 OCNF 2 NF 2 NF 2 NF 2 F2F2F2F2Fluorine HF CH 3 CH 2 CH 2 CH 2 OCNFH NF 2 NF 2 NF 2 Formation of Powerful “Tris” Oxidizers

30. U.S. Secret Rocket Fuel Research at Thiokol Chemical Company  Some “Bis” compounds were made as polyurethanes to create solid oxidizer-fuel combinations. to create solid oxidizer-fuel combinations.  “Tris” oxidizers were mixed with various polymers to form solid propellant materials that initially to form solid propellant materials that initially showed great promise for use in rocket fuels. showed great promise for use in rocket fuels.

31. What happened to the secret rocket fuel research programs?  The research and the spying made no impact on the space program of either the U.S. or the Soviet Union. space program of either the U.S. or the Soviet Union.  The difluoramine compounds had inadequate stability and performance to be practical as rocket stability and performance to be practical as rocket propellants for weapons systems. propellants for weapons systems.  Both sides continued to use other materials and the work was declassified a few years later. work was declassified a few years later.

32. Future Rocket Propulsion Systems  In order to travel beyond our solar system, future rockets must be able to travel at very high speeds, rockets must be able to travel at very high speeds, ultimately at or near the speed of light. ultimately at or near the speed of light.  Some of the concepts being explored to achieve this goal are: goal are:  Ion Engines using a gas plasma  Solar-powered electric propulsion  Nuclear-powered rockets  Anti-matter propulsion

33. Ion Engines are Close to Reality  A new type of ion engine called VASIMR® uses argon, xenon or hydrogen gas injected into a tube argon, xenon or hydrogen gas injected into a tube surrounded by a magnet. surrounded by a magnet.  A series of radio wave devices turn the cold gas into a superheated plasma (ionized gas). a superheated plasma (ionized gas).  The expanding magnetic field at the rocket’s nozzle converts the plasma’s thermal motion into a converts the plasma’s thermal motion into a directed flow, thereby producing thrust. directed flow, thereby producing thrust.  Solar or nuclear power will be used to generate the electricity needed to operate the system electricity needed to operate the system

34. VASIMR® Design (Variable Specific Impulse Magnetoplasma Rocket)  Ion engines like these have very low thrust, but very high specific impulse, so the rocket moves faster and uses much specific impulse, so the rocket moves faster and uses much less fuel than chemical rockets once the spacecraft is beyond less fuel than chemical rockets once the spacecraft is beyond earth’s gravitational field. earth’s gravitational field.

35. Space Travel with Ion Engines Artist’s concept of a solar-powered spacecraft built with 4 VASIMR® rocket engines headed to the moon. Travel to Mars is expected to take only 3 months compared to 9 months for conventional systems. compared to 9 months for conventional systems.

36. Bibliography 1.Castellano, J.A., “Rocket Science & Russian Spies,” American Scientist, 96, 490 (2008). 2.Kalugin, O. with Montaigne, F., “The First Directorate,” St. Martin’s Press, New York, 1994. 3.VASIMR® is a development of the Ad Astra Rocket Company, Houston, Texas: http://adastrarocket.com http://adastrarocket.com