From Earth to Orbit An Assessment of Transportation Options (1992) / Chapter Skim
Currently Skimming:
5 Propulsion Capabilities for Earth-to-Orbit Launch Vehicle
5 Propulsion Capabilities for Earth-to-Orbit Launch Vehicle
Pages 40-61
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 40... ...
Some other upper-stage engines were also developed in this time period for DoD, such as the nitrogen-tetroxide/Aerozine-50 Transtage engine. The third generation of liquid engine development produced only the Space Shuttle Main Engine (SSME)
|
From page 41... ...
However, large liquid rocket engines are based on technologies from the 1950s and 1960s, with the exception of the SSME. Meanwhile foreign entities, mainly Arianespace, the National Space Development Agency of Japan (NASDA)
|
From page 42... ...
42 _ _ ~ ' V, Cal m o ~ a, ~ — ~ ~ ~ Ct _ _ Cal V, .= {,4 a: U
|
From page 43... ...
43 Cal .
|
From page 44... ...
44 Cal I:: ._ Cal Ct m 1 a' · _ CO a' · _ x o o z Ct o .~ Ct it; I_ Ct V)
|
From page 45... ...
They use liquid oxygen and a hydrocarbon fuel, a relatively low chamber pressure, and a gas generator cycle that results in a relatively low specific impulse (i.e., performance) for this propellant combination.
|
From page 46... ...
It is the understanding of the Committee that funding for turbopump development has been partially eliminated in the proposed FY 1993 budget. However, the Committee considers development of the unproved turbopumps necessary and the Advanced Turbopump Program of high priority for the future reliability of the Space Shuttle Main Engine.
|
From page 47... ...
Flight-Proven International Engines and Motors The following is an evaluation of some specific foreign rocket engines and motors that the Committee believes to be especially relevant to the considerations in its charge. In overview, the foreign launch vehicles use propulsion systems incorporating modularity to venous degrees, which brings a variety of benefits.
|
From page 48... ...
The qualification and flight status of this engine makes it attractive for direct application in a heavy lift launch vehicle liquid booster stage. Aerojet, Pratt & Whitney, and Rocket~yne are currently engaged in negotiations to test and/or acquire the RD-170 from the engine manufacturer, NPO Energomash.
|
From page 49... ...
Normal Thrust (100%~: Minimum Thrust (70%~: Mixture Ratio: Specific Impulse (100%~: Specific Impulse (70%~: Chamber Pressure: Dry Weight: Area Ratio: Length: Nozzle Diameter: Design Life: Demonstrated Reliability: 500th Unit Cost Goal: 650,000 Ib 455,000 Ib 6.0 428.5 s 427.3 s 2250 psia 9930 Ib 45:1 160 inches 96 inches 10 missions 0.99 @ 90% $5.3M FIGURE 2 Characteristics of the proposed liquid-oxygen/liquid-hydrogen Space Transportation Main Engine (STME)
|
From page 50... ...
This design philosophy influenced the choice of lower chamber pressure and the use of the gas generator cycle, design factors that result in a lower delivered specific impulse for the STME. Attendant with these choices is a significant reduction in the turbopump outlet pressure that, in turn, is expected to result in a more robust design.
|
From page 51... ...
This approach is consistent with highly successful launch vehicle experience in the international space community, as evidenced by the extensive Russian inventory of strap-on propulsion systems, the Ariane family of launch vehicles, and the Delta launch vehicles. Advanced Solid Rocket Motor (ASRM!
|
From page 52... ...
The Solid Rocket Motor Upgrade (SRMU) is a segmented rocket motor design being developed to provide more lift capability for the Titan IV launch vehicle.
|
From page 53... ...
AlAA; and manufacturers data sheets.
|
From page 54... ...
ATAA; and manufacturers data sheets. ENGINE AND MOTOR TESTING System Reliability and Tests One point that is not always clear in discussions of the reliability of liquid rocket engines versus solid rocket motors is that the solid rocket motor test includes all facets of the propellant delivery system, whereas the liquid rocket engine may not.
|
From page 55... ...
Propulsion Test Facilities The nation's capability for testing liquid rocket engines and solid rocket motors is becoming constrained by the pressures of residential and commercial development in the vicinity of rocket manufacturers' facilities and the increasingly stringent environmental standards being imposed. The following is a summary of the most likely test sites for future engine and motor development activities, including a brief assessment of potential restrictions and constraints.
|
From page 56... ...
rocket test facilities capable of handling SSME engines as well as larger engines. NASA/Stennis Space Center, Mississippi, has 4 very high thrust test stands available for liquid-oxygen/liquid-hydrogen rocket engine testing.
|
From page 57... ...
Data suggest that pollution due to combustion products from launch vehicles, at the frequency and scale that is anticipated, is not significant in comparison with other 6 American Institute of Aeronautics and Astronautics. Atmospheric Effects of Chemical Rocket Propulsion.
|
From page 58... ...
PRIORITIES FOR VESTMENT A plan is needed to provide an array of engines with a range of thrust levels and propulsion system capabilities for all stages of future launch vehicles. The proposed STME can be used for first stages of future launch vehicles.
|
From page 59... ...
The Redesigned Solid Rocket Motor also deserves future investment to ensure the continued success of Space Shuttle operations. In particular, the RSRM could benefit from continued investment in improved manufacturing technology to ensure the repeatability of manufacture and nondestructive inspectability of the motor.
|
From page 60... ...
60 in a, a, g m .c I_ Ct ~0 ._ I o V: o Cal C~ .a C)
|
From page 61... ...
The time scale for the development of a 35,000-pound payload class vehicle, would permit investment in hybrid rocket motor development now, so that its status is advanced to the point at which it can be quantitatively evaluated in competition with solid and liquid bipropellant systems designed to directly comparable criteria. Two liquid rocket engines that the Committee also believes are candidates for booster applications are the F-lA and the RD-170 engines as discussed earlier.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.