AIR LAUNCH Grand Trade Study

1. AIR LAUNCHGrand Trade Study

2. Flight Path Illustration 9 Cruise to optimum separation latitude/ longitude. Simultaneous production of LOx on aircraft and transference to rocket stage Ascent to target orbit Rocket ignition. Ascend to separation point 40,000 ft at M=0.82 Ascent to optimum cruise altitude for cruise/ Lox production. In-flight refueling if necessary 8 4 5 3 2 Powered return to landing site. In-flight refueling if necessary Optional Direct Ascent 1 6 Take-off from standard runway Landing at original or auxiliary runway Ferry back to processing site 7

3. Conceptual Design Stage “It has been estimated that at least 80 percent of a vehicle’s life-cycle cost is locked in by the concept that is chosen.” NASA/TP-2001-210992 The conceptual design fixes the costs. The conceptual design has least detail. Therefore, there MUST be inherent rationale in the design that will tend to lower costs. Conceptual Design • Air launch has such rationale - keeps vehicle smaller • use of existing optimum technologies for 1st stage • true horizontal take-off & landings • inherent safety advantages • more design margin than SSTO

4. Examples of Air Launch’s Scope Boeing AirLaunch Anticipated Performance Modified C5 Antonov - 225 ALTO with LOX collection Dual C-5 Andrews’ Alchemist Anticipated Time & Difficulty 3rd Gen.

5. Velocity Losses (Sea Level vs. Air Launch) Lower Atmosphere = Losses Overwhelmingly, V losses are incurred in the first 10 km of ascent. Velocity losses represent 20% of the ideal ascent V for a typical sea-level launch, but only 8-10% of an air launch. Air launch inherently: • Reduces gravity losses • Reduces drag losses • Reduces engine pressure losses • Reduces trajectory losses (plane changes)

6. sea-level Isp368 sec • altitude Isp430 sec • vacuum Isp452 sec Altitude Advantages High-altitude air-launch dramatically reduces the need for altitude-compensating engines. Improved Specific Impulse (mission average) Air launch inherently: • Increases average Isp • Increases vacuum Isp • Increases initial velocity (both by local air speed & by equatorial launch) Typically SSME or RL-10 derivatives with extended (passive) skirts up to 465 seconds Velocity Addition • Nominally 250 m/s for conventional subsonic transport relative speed • 50 m/s - 200 m/s for earth rotational speed

7. Staging Rationale

8. Near Term Development Concerns

9. Trade Space

10. Antonov An-225 Mriya Masses Max takeoff 600 MT Payload 250 MT Fuel Capacity 200 MT Operational in 1987; recently refurbished for commercial cargo transport Dimensions Length 84.0 m Wingspan 88.4 m Originally designed for air launch Existing Aircraft Boeing 747-400 Freighter • Masses • Max takeoff 397 MT • Payload 113 MT • Fuel Capacity 160 MT • In operation since 1968; first utilized as Shuttle carrier in 1977 • Dimensions • Length 70.6 m • Wingspan 64.4 m • Estimated $160 M per aircraft

11. Air Liquefaction System Supercritical cold air stream is throttled to low pressure, highly liquefied air stream LOX product pumped to spacecraft Turbine extracts enthalpy from air stream as useful work, driving the rotary distillation unit and producing a low temperature, mildly liquefied feed stream Nitrogen exhaust used for aircraft purge Counterflow heat exchanger for regeneration Rotary distillation unit, driven by turbine power, enriches and separates LOX from liquid air Air compression system with actively cooled stators driven by turboshaft engine power

12. An-225 TSTO 1st Stage Rocket LOx/LH2 Rocket GLOW = 376 klb Propellant = 261 klb T/W = 1.69 2nd Stage Rocket LOx/LH2 Rocket GLOW = 170 klb Propellant = 119 klb T/W = 0.86 Payload 25 klb to LEO Notes Three SSME (engine out capability) Vacuum thrust=923.3 klbf, vac Isp=450 sec Eight RL-10A-4 Vacuum thrust=145.6 klbf, vac Isp=450 sec Aluminum Lithium tanks 30.0% mass growth Aircraft Take-off mass = 1.32M lb Separate at Mach=0.82, alt=40k ft, Q=189 lbf/ft2 GE90-115B engines 275’ long, 290’ wingspan

13. An-225 SSTO with LOX collection Rocket LOx/LH2 Rocket GLOW = 1,652 klb Propellant = 1,389 klb T/W = 1.3 Payload 50.6 klb to LEO Aircraft Take-off mass = 1.32M lb Separate at Mach=0.82, alt=40k ft, Q=185 lbf/ft2 GE90-115B engine 275’ long, 290’ wingspan Notes Four New LH2 Engines Vacuum thrust=2,147 klbf, vac Isp=462.5 sec Graphite-epoxy Tanks 20.0% mass growth

14. Dual C-5C TSTO 1st Stage Rocket LOx/LH2 Rocket GLOW = 443 klb Propellant = 341 klb T/W = 1.58 2nd Stage Rocket LOx/LH2 Rocket GLOW = 353 klb Propellant = 256 klb T/W = 1.45 Payload 49 klb to LEO Notes Three SSME (engine out capability) Vacuum thrust=923.3 klbf, vac Isp=450 sec Two SSME (engine out capability) Vacuum thrust=923.3 klbf, vac Isp=450 sec Aluminum Lithium tanks 13.0% mass growth Aircraft Take-off mass = 1.68M lb Separate at Mach=0.75, alt=38k ft, Q=154 lbf/ft2 GE90-115B engines 230’ long, 308’ wingspan

15. Oversized Cargo Such vehicle can and do exist!

16. Dual Fuselage Aircraft Russian Design Commercial Aircraft in Flight Dual C5 as Proposed for Space Shuttle

17. In turboshaft mode, it produces 20 MW of shaft power to drive air compression system for LOX production In turbojet mode, engine would provide additional thrust for takeoff and spacecraft/aircraft separation maneuver Pair of afterburning F119s at altitude would be like adding a fifth engine to the 747 carrier aircraft Use of the F119 saves development time and money since the F119 is already designed to do what we want! Capitalize on the advanced technologies already in place if possible! Existing turbojet & turboshaft engines Existing subsonic aircraft structures & controls Existing LOX production methodologies Existing infrastructure (airfields, manufacturing volume, parts supply, maintenance, etc.) Existing highly reliable rocket upper stages (bell housing, LOX/LH2, Expander Cycle, cylindrical tanks and structures, etc.) Exploiting Mature Technologies

18. Progressive Development Paths Upper Vehicle Mass Boeing 747 Light Antonov - 225 LOX Collection or Engine/Frame Mods Medium LOX Collection and Engine/Frame Mods LOX Collection Heavy Dual C5 Jumbo Super Heavy New Aircraft (Cargo Pod)

19. TD-30 study with support from: MSFC TD-10 & TD-40 Langley Research Center Cooperation and interfacing with: Boeing AirLaunch Program Andrews Alchemist (SLI effort) Air Force (both Mobility Command and Space Command) Other commercial contacts (Air products, SpaceWorks, Antonov, Lockheed/Martin, etc.) Investigating further collaboration within and without TD Rocket Assisted Aircraft 3rd Gen. Synergy Dual C5 Aircraft New Production Aircraft Generic Trade Space Two Stage Rockets Single Stage Rocket LOX Collection Other Existing Aircraft Reusable Stage(s) Schedule & Collaboration 2002 Schedule

20. Rocket operations above the dense atmosphere significantly reduces drag/gravity losses and increases engine Isp Air Launch provides operational flexibility by launching into any orbit inclination, further reducing mission V Air Launch holds great promise to reduce operations, integration and overall cost of mission Use of existing commercial/military hardware, even for new aircraft design, is advantageous Many issues, including aircraft performance and liquefaction system, remain to be solved Stress on rocket wings Refinement of LOX collection systems Required aircraft modifications, refinement of aircraft performance Refinement of potential separation conditions Conditions achievable by aircraft Separation distance required before ignition or full power up Option of low throttle before separation Refinement of aerodynamic analysis Summary

21. Back Up Charts

22. Supersonic Difficulties & Conflicts

23. Nature’s Subsonic & Supersonic Conflicts Engine design Wing design Lift/Drag Sweep wings Wide wings Subsonic Supersonic Turbofan vs. Turbojet M = 1 Ref. NASA SP-472 This compromise, to date, has only generated poor results in both regimes.

24. Where Is The Breakeven Point? 3+ Ref. RM-3132-PR You must fly faster than Mach 3 to even match the payload performance of a subsonic vehicle - then evaluate the extra cost and risks of such a supersonic first stage vehicle!

25. The Effect on GLOW The definition of this structural ratio allows us to define a mass multiplier that relates the amount of propellant and propellant-sensitive structure required to put a kilogram of payload into orbit. The mass multiplier helps us see the extreme difficulties of ETO launch caused by the exponential nature of the rocket equation. λ=12% λ=11% λ=10%

26. The Need for More Study “Air Launch” - From NASA Center for Aerospace Information - 164 documents - 42 appearing to have most relevance Only 2 NASA Official documents (TM or CR) Only 2 others had NASA authors In all 4 cases it was not applicable to subsonic launches! (All others are Air Force/industry or foreign) Space Shuttle history book (Jenkins 2001) - Well over 100 pages for preliminary design history - 1 page for air launch ideas (page 73 of 513) “…neither NASA nor the Air Force displayed any interest in the concept, and none of these designs progressed beyond paper studies.” “From the available documentation it does not appear that any of Romick’s designs were taken seriously by NASA or the Air Force, and they remain but interesting footnotes in history.”

27. Supersonic Military Technology Transfer Military designs small aircraft for maneuverability, high rate of climb and short-range flight at supersonic speeds (i.e. no major heat-expansion issues) Military engines are made for performance - not fuel efficiency, low maintenance, minimal noise, or other factors Extended range in military aircraft is accomplished by aerial refueling (rather often) or long subsonic speed operations Commercial transports have much longer operating lifetimes and must conform to the civilian airport requirements Higher altitude operations requires pressure suits to protect against sudden decompression “A contributing factor in the underestimation of time and costs of commercial SST development was the overly optimistic projection of the value of supersonic military flight experience.” NASA SP-472

28. Other Aircraft Alternatives • Airbus A380 • Will not be in production until 2006 • Is European made • Roughly same cargo class at 747 • Lockheed C-5A • Designed for semi-prepared runways, thus extra weight • Very high rear wing • Roughly same cargo class at 747 • Might be modified to carry 2nd stage ‘inside’ and dropped from ‘under’ fuselage? • Specially Designed - Unique Aircraft • High initial cost • Long lead time to design & build • Marginal gains in performance • Higher operational costs • Less commercial potential for other customers or resale • Modified 747 Aircraft • Good performance • Reasonable costs, time and margins • Excellent commonality to existing infrastructure/markets Existing jet aircraft are close to optimal design.

29. Long Term Benefit to U.S. Space superiority (commercially and strategically) Support struggling aircraft industry with jobs Fulfill NASA’s alternate access to space requirement Provide reliable, low cost launch operations Recapture significant launch market share Reach NASA’s first goal of 1000x astronaut safety Lay groundwork for routine space travel Widen the potential ownership of space vehicles to commercial and private ventures U.S. resolve: icon of national pride out of horror of aircraft terrorism

30. Air Launch - Rocket Comparison The “differential or ” always favors an aircraft 1st-stage over a rocket.

31. Air launch is best option for humans and cargo because safety and reliability are inherent in the system Air launch offers unmatched orbital flexibility over sea-level launch ALTO evolves to include new 2nd and 3rd-generation technologies 6-8 MT payload capability captures most of LEO launches Not a replacement for heavy-lift launch If successful, air launch will be used to launch spacecraft for the next 20 to 40 years… ALTO Summary