DOW-UAP-D124, AAWSAP DIRD, Space Access: Where We’ve Been and Where We Could Go, March 2010

This document is a Defense Intelligence Reference Document (DIRD), a technical reference format used by the Defense Intelligence Agency (DIA) to capture baseline knowledge on a specific topic for later analytic use. DIRDs are best understood as reference and synthesis products rather than as original research. It is one of 38 DIRDs produced under the Advanced Aerospace Weapon System Applications Program (AAWSAP) between 2009 and 2011. Because AAWSAP’s scope permitted a broad range of supporting topics, not every DIRD in the series directly concerns aerospace systems or future threat assessment. The following summary reflects the DIRD’s scope and framing at the time of writing and should not be read as implying current validation of the concepts discussed. This DIRD is a historical and conceptual survey of space access systems, contending that the main barrier to routine access to space is a failure to build durable, reliable, operational hardware and the supporting infrastructure needed for regular service to and from low Earth orbit. The report reviews earlier launch and aerospace concepts, especially reusable and aircraft-like approaches, and suggests that U.S. space access development became too strongly centered on expendable rockets derived from ballistic missiles rather than bespoke systems designed for repeated space access and payload delivery. Its central claim is that meaningful future progress will depend on creating a purpose-built space transportation infrastructure, including frequent round-trip capability and orbital support networks, rather than continuing to rely on one-off launch vehicles. Overall, the document presents a forceful case for infrastructure-first space development, though its characterization of past technological choices is more assertive than a fully neutral account of past U.S. space programming.

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Defense
Intelligence
Reference
Document
Acquisition Threat Support
8 March 2010
!COD: 1 December 2009
DIA-08-1001-006
Space Access: Where We've
Been ... and Where We Could
Go
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Space Access: Where We've Been . . . and Where We Could
Go
Prepared by:
Acquisition Support Division (DW0-3)
Defense Warning Office
Directorate for Analysis
Defense Intelligence Agency
Author:
AAP Person 67
Administrative Note
COPYRIGHT WARNING: Further dissemination of the photographs in this publication is not authorized.
This product is one in a series of advanced technology reports produced in FY 2009
under the Defense Intelligence Agency, Defense Warning Office's Advanced Aerospace
Weapon System Applications (AAWSA) Program. Comments or questions pertaining to
I,
this document should be addressed tolAAP Person 1 AAWSA Program
Manager, Defense Intelligence Agency, ATTN: CLAR/DW0-3, Bldg 6000, Washington,
DC 20340-5100.
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Contents
Introduction ............................................................................................................v
Propulsion Perspective........................................................................................... 1
Hypersonic Configuration Concepts........................................................................ 2
Thermodynamics and Materials............................................................................ 16
The Qu Tube ......................................................................................................... 23
Rocket Propulsion ................................................................................................ 25
Up-and-Down Operations ..................................................................................... 30
Launch Options .................................................................................................... 33
Atmospheric Variations ........................................................................................ 35
Conclusion............................................................................................................ 37
Appendix A: Historical Perspective....................................................................... 43
Appendix B: Aeropropulsion Integrated Vehicle ................................................... 46
Appendix C: TAV Operational Costs ...................................................................... 47
Appendix D: Landing Ellipses for Hypersonic Gliders............................................ 48
Figures
Figure 1. Hardware Flow ........................................................................................vi
Figure 2. Impact of Air-Breathing Rocket ................................................................1
Figure 3. HSVS Hypersonic Cruise Aircraft Showing True Skin Temperature ...........3
Figure 4. Hypersonic Rocket-Powered Glider Hypersonic Air-Breathing Cruiser......4
Figure 5. Delta-Lifting Body Designs .......................................................................5
Figure 6. Martin Marietta X-24 A & B Research Gliders............................................7
Figure 7. Detailed Design Analyses Show the Weight Trends are as Much a
Function of Configuration Family as Lift-to-Drag Ratio ............................9
Figure 8. High-Performance Hypersonic Glide Aircraft ..........................................10
Figure 9. NASA Langley Wing-Body Configuration WB-004 with Critical Areas for
Wing Bodies Identified...........................................................................11
Figure 10. FDL-7C/D and FDL-7MC Lifting-Body Configuration..............................12
Figure 11. FDL-7C/D with a DuPont Retractable Inward-Turning Inlet .................12
Figure 12. Comparison of FDL-7C/D and Model 176 ..............................................13
Figure 13. Sufficient Cross Range (L/D) Means There is No Waiting to Return ..... 14
Figure 14. Hypersonic Glider Characteristics .........................................................15
Figure 15. Both Delta Planform Lifting Body (Dynasoar) and Model 176 Offer
Superior Landing Performance .............................................................16
Figure 16. McDonnell Aircraft Company Roll-Bonded Titanium Structure ..............17
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Figure 17. Model 176 in the McDonnell Douglas Hypervelocity Impulse Tunnel ....18
Figure 18. FDL-7C/D, Model 176 Entry Temperature Distribution .........................19
Figure 19. Even At Mach 12, Embedded Vortices in the Boundary Layer Alter the
Local Heat Transfer ..............................................................................19
Figure 20. Thermographic Phosphor Image of Model 176 at Near-Maximum
Angle of Attack.....................................................................................20
Figure 21. From L/D Maximum to Maximum Angle of Attack, There Is Always a
Cool Sub-layer Adjacent to the Wall .....................................................20
Figure 22. This 1988 SEP Bordeaux SiC/SiC Panel Could Sustain Temperatures of
up to 3,000°F........................................................................................21
Figure 23. UBE Corporation's Tyranno Cloth..........................................................21
Figure 24. A Porous Nickel Tip Oozing Water ........................................................21
Figure 25. FDL ASSET Flight-Tested From Orbital Speeds to Evaluate 1960s
Materials ..............................................................................................22
Figure 26. Heat Pipe Shuttle Leading Edge Designed and Built by McDonnell
Douglas Astronautics ...........................................................................22
Figure 27. Boost-Glide Strategic Vehicle with Pratt & Whitney XLR-129 Rocket
Engine Installed ...................................................................................25
Figure 28. XLR-129 ...............................................................................................25
Figure 29. Two Rocket Air-Breathing Rocket Cycles to Mach 5.5 ...........................27
Figure 30. HOTOL Evolution: From Aerodynamic Optimum Configuration to
Practical Launcher Configuration .........................................................27
Figure 31. LACE Air-Breathing Rocket ...................................................................29
Figure 32. The FDL-7 Class of Vehicles ..................................................................29
Figure 33. Takeoff and Landing Speeds of Minimum-Sized Launchers ...................30
Figure 34. Horizontal launch Not Practical Unless Weight Ratio Less Than Four ...31
Figure 35. Propellant Tanks That Are Not Reentry Vehicles Greatly Reduce
System Weight .....................................................................................33
Figure 36. Simple Horizontal Integration and Vertical Launch Provides Rapid
Launch Capability .................................................................................34
Figure 37. A Vertical Launch Complex Provides Vertical Toss Back Booster
Recovery and Horizontal Landing Facilities for the Hypersonic Gliders 34
Figure 38. A 1964 MDC Astronautics, St. Louis, Briefing........................................35
Figure 39. Earth's Atmosphere ..............................................................................36
Figure 40. FDL-5 Scale Model of A Stage and One-Half..........................................37
Figure 41. The FDL-7 and Model 176 Class of Hypersonic Gliders..........................37
Figure 42. Hypersonic Decelerating.......................................................................38
Figure 43. Where We Are Today ............................................................................39
Figure 44. Where We Could Be If We Can Recapture the Engineering Confidence
and Expertise of the Apollo/Saturn V Era .............................................40
Figure 45. TAV Operational Costs ..........................................................................47
Figure 46. Landing Ellipse .....................................................................................48
Tables
Table 1. Characteristics of Selected Flight Dynamics Laboratory Hypersonic
Glider Configurations During the 1958-68 Timeframe ...............................6
Table 2. Elements of the Space Infrastructure Shown in Figure 44 .......................41
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Space Access: Where We've Been . . . and Where We Could
Go
Introduction
Development of commercial access to space by our budding space­
faring civilization is a straightforward effort dominated by
propulsion and reliability. The initial focus should be on schedulable,
dependable access to and from low Earth orbit (LEO). For years we
have known the means to accomplish such a task but have lacked a
dedicated organized effort. The key requirement is to develop a
robust and not necessarily a low-cost infrastructure, without which
commercial exploitation of LEO and the moon will not be possible.
This is a matter of skill; operational hardware based on durable,
reliable, and demonstrated components; and operational systems. It
is not necessarily a matter of technology. However, technology
discovery and development are necessary for future space travel
beyond Earth's environs. This paper addresses these issues by
providing a running account of the historical details associated with
the development of the myriad systems proposed and tested to
provide access to space.
Among the many advances in space access that will be possible in
the future,1 the key technology developments will be in the area of
propulsion, because without these we are confined to our solar
system by flight times limited to a project team's functional life. The
Pioneer spacecraft were fortunate to be monitored for 20 years.
However, the issue facing our spaceflight organizations is the lack of
a durable, consistent, schedulable, and frequent hardware system to
and from space assets such as the International Space Station.
In October 1958, the author's job in the vertical wind tunnel at
Wright-Patterson Air Force Base abruptly changed; hypersonic and
high-temperature flows became a new focus. What was then the
Aircraft Laboratory was to become the Air Force Flight Dynamics
Laboratory (AFFDL), with a focus on space flight. Al Draper of the
AFFDL began working with a select group of aerospace firms on
hypersonic gliders. The initial requirement from the Air Force was to
quickly find operational access to space. Technology application,
hardware design and fabrication with an innovative application, and
extending the industrial capabilities of the time were very much the
issue, as exemplified by the Lockheed A-12/SR-71. When asked
about space access at the time, a group of Aerospace Corporation
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veterans responded, "It was not a technology issue; it was a
hardware issue."
In a keynote address to the Aeronautical Revolutionary Concepts
Workshop sponsored by the Vehicle Applications Panel of the
National Research Council and held at NASA Ames in July 1984,
then-Assistant Secretary of Commerce for Productivity, Technology,
and Innovation Dr. D. Bruce Merrifield identified the problem of
translating ideas into products as preparing technology for product
manufacture. Dr. Merrifield drew an analogy between this step and
Major League Baseball's farm system, which prepares skilled but
untrained players for the major leagues. The United States assigns
projects to accomplish technology tasks so the flow of production­
ready hardware is always improving and is not fixed (see Figure 1).
Innovation Focus:
Preparation of Technology for Application
---r-----7to10years-----~1
------~--•"-""_••" _, ,__...;.;...;..:.,:. .,- ---,....-=----_-_-_,---..._,... . --""'".'.-.-......... ., .............
.... ·····•.. ..
__ __ ,••· ' •,
Prototype
Idea PrOCluct and Pilot lntenm + Commercialization ·.
._Generation___., .__ __, Develooment Plant I Manufacture
lnve~n Translation ··•....
··•.
••······· ...••
·····••..................... •· ROLP •..................................•1:i:t··fA••
Gap in effective No Gap in
100/o Cost 900/o Cost
preparation for transformation
application to production
in United States
Or.O. Bruce Merrifield
Oeptment of Commerce
1983 Innovation In Aeronautics
Assistant Secretary for Productivity,
Wortcshop, NASA AMES
Technology and Innovation
Figure 1. Hardware Flow
Saturn I and Saturn V could be readied for a moon flight in such a
short time because most of their hardware was based on a frozen
design, proven production processes, and adaptation of existing
hardware. Using a similar approach, current industrial capabilities
can create the next practical system for accessing space. In the late
1950s and early 1960s, the U.S. Air Force was working toward an
operational capability analogous to its B-52 fleets: flight operations
when required or "on demand." After NASA was assigned
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responsibility for space access, that Air Force's focus switched to
surveillance, communication, and Global Positioning System
satellites.
In the late 1950s, there existed a predisposition-forced by the
military competition between the United States and the former
Soviet Union-to use rockets derived from military ballistic missiles.
That decision curtailed efforts to develop alternatives to chemical
rockets together with practical commercial developments. With the
orbiting of Sputnik, the aircraft path to space, as represented by the
X series of planes, ended with the X-15. With the X-15's demise, all
efforts to fly aircraft to space ended, replaced by the more familiar
(but less practical) strategy of loudly blasting to space with
expendable rockets derived from undertested ballistic missile
hardware, as documented in early failures.
Like their ballistic missile progenitors, current expendable rockets
can be launched only once. With the exception of the experimental
Delta Clipper developed and operated by William Gaubatz and the
late Pete Conrad, no operational launcher has ever successfully
aborted. In this context, a reusable launcher is simply an
expendable with some parts reused a few times. Thus, neither the
United States nor the Soviet Union/Russia has ever realized a truly
commercial approach to space travel, although the Soviets came
close to taking the first step with the since-terminated
Energia/Buran system. Both the United States and the Soviet
Union/Russia historically have generated a large number of concep