Space vehicles and launch vehicles are a single subarea within the Space Platforms technology area. In many cases, technologies for space vehicles and launch vehicles are unique and for that reason they are discussed separately (Sections 3.1 and 3.2); the propulsion subarea is described in Section 3.3.
The warfighter must have the ability to deploy, sustain, augment, and recover on-orbit space forces and assets in support of the ground mission. The launch vehicles (an element of the space vehicles and launch vehicles subarea) must provide this service in a reliable, responsive, and affordable manner.
The AFSPC 96 Spacelift mission area plan (MAP) details the launch vehicle task as: "generate the launch mission, execute the launch mission, perform post-launch operations, employ the launch ranges, spacecraft initialization, operate space assets, and reposition space assets." The Spacelift MAP further describes technology required to support future concepts, which in turn will eliminate the current deficiencies of existing systems.
Launch vehicle technologies target reducing the cost of launch; making launch schedules more responsive to user requests; improving the flexibility and operability of the range to support multiple users while significantly reducing operating costs; improving the ability to reposition on-orbit assets; improving the ability to recover, repair, and deploy on-orbit assets; and providing the additional capability of "global mobility via space."
The set of DoD S&T efforts included in the launch vehicles subarea encompass structures, aero/thermodynamics, GN&C, recovery, robotics/docking, survivability, electrical power, and range operations.
3.1.2.1 Goals and Timeframes. The subarea goals, system payoffs, and timeframes for the launch vehicles technologies are listed in Table VIII-2. The goals and payoffs are shown for the ELV, upper stage/orbital transfer vehicle (US/OTV), and RLV. The technologies and associated objectives required to achieve the space vehicles goals and payoffs are detailed in Table VIII-3.
| Space Vehicles | FY 2000 | FY 2005 | ||||
|---|---|---|---|---|---|---|
| ELV | US/OTV | RLV | ELV | US/OTV | RLV | |
| Subarea Goals | ||||||
| MassFraction | 0.058 | 0.089 | 0.093 | 0.0.44 | 0.067 | 0.0.7 |
| System Cost | $39M | $40M | $329M | $22M | $29M | $224M |
| Flts Between Referb | - | N/A | 5 | - | 5 | 10 |
| System Payoffs | ||||||
| $/lb Mass Delivered | $3,500 | $4,000 | $5,500 | $2,000 | $2,500 | $3,700 |
| No. Transfers/Vehicle | - | 1 | - | - | 25 | - |
| Turnaround Time | - | N/A | 50 days | - | 5 days | 25 days |
| No. Flts/Vehicle | - | - | 150 | - | - | 200 |
Table VIII-3. Launch Vehicles Subarea Technology Objectives
| Year | Technology | Objectives |
|---|---|---|
| 2000 | Structures | Reduced structural mass: OTV 35%, ELV 40%, RLV 40% Reduced structural cost: OTV 40%, ELV 40%, RLV 40% Reduced dynamic launch loads ELV, RLV: Lateral 5x, Axial 5x Reduced on-orbit disturbances: OTV 10x |
| Aero/Thermal | RLV: increase high-temp materials reusability 400 cycles | |
| GN&C | ELV/strategic sustainment: gyroscopes with 0.01-deg/hr drift, 8-yr MTBF | |
| Recovery | RLV: recoverable mass of 90% | |
| Robotics/Docking | OTV: replenishable & replaceable of 0% | |
| Survivability | OTV: decrease radiation safety factors by 5x OTV: improve debris knowledge by 5x | |
| Power | Increase primary battery cycling rate ELV, RLV: 10 cycles Increase battery cycling OTV: 35000 cycles | |
| Range Operation | RLV: range turnaround time of 36 hr Strategic sustainment: NDE on solid rocket fuel | |
| Vehicle Control | OTV: reduce control costs by 30% | |
| 2005 | Structures | Reduced structural mass: OTV 50%, ELV 55%, RLV 55% Reduced structural cost: OTV 55%, ELV 55%, RLV 55% Reduced on-orbit disturbances: OTV 10x |
| Aero/Thermal | RLV: increase high-temp materials reusability 500 cycles | |
| GN&C | ELV/strategic sustainment: gyroscopes with 0.01-deg/hr drift, 15-yr MTBF | |
| Recovery | RLV: recoverable mass of 95% | |
| Robotics/Docking | OTV: replenishable & replaceable of 85% | |
| Survivability | OTV: decrease radiation safety factors by 4x OTV: improve debris knowledge by 10x | |
| Power | OTV: BOL conversion efficiency of 35% OTV: specific energy density of 150 Wh/kg OTV: PMAD efficiency of 93% | |
| Range Operation | RLV: range turnaround time of 24 hr Strategic sustainment: NDE on solid rocket fuel | |
| Vehicle Control | OTV: reduce control costs by 40% |
3.1.2.2 Major Technical Challenges. Major technical challenges for expendable launch vehicles (ELVs) include development of lightweight, low-cost, composite structures and propellant tanks; development of low-cost, fault-tolerant avionics; and development of lightweight, low-cost, and high-power density batteries. Reusable launch vehicles will require major breakthroughs in structures, thermal protection systems for reentry vehicles, instrumentation systems for vehicle health management and component failure diagnosis, propellant handling components and systems, and modular component designs to facilitate rapid refurbishment or repair.
3.1.2.3 Related Federal and Private Sector Efforts. Currently identified technology efforts include those by the USAF evolved ELVs (EELVs), NASA X-33/RLV, McDonnell Douglas Delta III, Lockheed Martin Atlas IIAR, Orbital Science Corporation Pegasus, and several other private sector startup programs to include teaming with foreign manufacturers (primarily, former USSR republics).
Launch vehicle investment is directed toward reducing the cost of launch vehicles while improving performance, reliability, autonomy, availability, and reusability.
3.1.3.1 Technology Demonstrations. At present, no technology demonstrations are uniquely associated with the launch vehicle subarea.
3.1.3.2 Technology Development.
Structures. This work is focused on the development of structures and structural control technology for DoD launch and ballistic missile vehicles. Work on tankage for launch vehicles is now being included in this technology effort. Work on nozzles and cases for rocket systems is not included here but is included in the space propulsion discussion (Section 3.2). Structures for hypersonic vehicles are not included in Space Platforms, but are covered under Air Platforms. In the same vein, work on ground-based ballistic missile interceptors is not covered here, but is covered under Weapons. This technology effort overlaps with space vehicle structures and space propulsion. The Advanced Composite Interstage Program is developing a new and innovative launch vehicle interstage concept using the composite isogrid design and fabrication technology. The Lightweight, Low-Cost Composite Payload Shroud Program is developing a payload shroud using the same structural concept but on a much more complex shape subject to significantly different loads. The use of composite isogrid structures will reduce fairing and interstage manufacturing cost and weight, resulting in reduced cost of launching space payloads and the ability to launch heavier/larger payloads into a higher orbits. The increasing DoD need to reduce launch cost has led to a significant investment increase in launch vehicle structural component and structural control technology. Programs are exploring active control, passive damping techniques, precision deployable orbital structures, and advanced mechanisms to reduce the structural load that space vehicles must survive during launch.
Aero/Thermal. This effort is focused on aerodynamic loads and thermal heating to which a launch vehicle is subjected as it ascends through the Earth's atmosphere. Reusable launch vehicles are also subject to such stresses on descent. This technology effort overlaps with space vehicle thermal management but usually deals with stresses of higher magnitude and shorter duration than do space vehicles.
Guidance, Navigation, and Control. This work addresses advanced science and technologies for launch from Earth. GN&C encompasses both launch vehicle and ballistic missile guidance. This technology effort overlaps space vehicle GN&C but has to deal with much higher acceleration rates.
Recovery. Developing the capability to recover assets from space and return them to Earth or refurbish/repair on-orbit is the thrust of this work. NASA's Space Shuttle is the only current system with any recovery capability.
Robotics/Docking. This focuses on developing technologies that enable autonomous docking procedures, remote materials, and propellant transfer.
Survivability. This addresses developing hardened components that are required to survive space launch and US/OTV space environments.
Electrical Power. To address the storage and distribution of electrical power onboard launch vehicles, emphasis is on battery technology to support short-duration, high-demand electrical loads and OTV power conversion efficiency and energy density of storage technologies.
Range Operations. This work focuses on safety, handling, and control technologies for segments of the launch vehicle system that do not fly but are directly tied to flight such as trajectory monitoring, command destruction, and range turnaround operations.
3.1.3.3 Basic Research. Basic research supporting the launch vehicle systems is leveraged from the space vehicle technology programs and from related federal, university, and private sector efforts.
