Engineering topics

Leingang, J. L.

Publications and source records attributed to Leingang, J. L..

3 records

NASA NTRS1993

Eliminating LH2 in LOX-collect space launchers - Key to on-demand capability

Two air-breathing reusable two-stage space launch vehicle concepts are proposed, in which the first stage employs turboramjet propulsion and the second stage uses rockets, which are expected to provide very rapid response launch of 10,000 lb polar-orbit payloads. In both concepts, liquid oxygen (LOX) for the second stage is collected during first stage ascent, thus eliminating the need for LOX ground servicing facilities. In the first concept, liquid hydrogen in the amount just sufficient to condense and collect second state LOX is the only cryogenic fluid that is loaded on the vehicle at takeoff. The second concept uses the heat sink of conventional jet propulsion fuel and water coolant to drive a lightweight adaptation of the commercial LOX production process, eliminating all cryogenics at takeoff. Both concepts should permit true launch-on-demand capability with aircraftlike ground operations.

Leingang, J. L.↗

NASA NTRS1992

Advanced ramjet concepts program

Uniquely advantageous features, on both the performance and weight sides of the ledger, can be achieved through synergistic design integration of airbreathing and rocket technologies in the development of advanced orbital space transport propulsion systems of the combined cycle type. In the context of well understood advanced airbreathing and liquid rocket propulsion principles and practices, this precept of synergism is advanced mainly through six rather specific examples. These range from the detailed component level to the overall vehicle system level as follows: using jet compression; achieving a high area ratio rocket nozzle; ameliorating gas generator cycle rocket system deficiencies; using the in-duct special rocket thrust chamber assembly as the principal scramjet fuel injection operation; using the unstowed, covered fan as a duct closure for effecting high area ratio rocket mode operation; and creating a unique airbreathing rocket system via the onboard, cryogenic hydrogen induced air liquefaction process.

Leingang, J. L.↗

NASA NTRS1992

Scramjet analysis, testing

A survey of supersonic combustion ramjet (scramjet) engine development in the US covers development of this unique engine cycle from its inception in the early 1960's through the various programs currently being pursued and, in some instances, describing the future direction of the programs. These include developmental efforts supported by the US Navy, NASA, and US Air Force. Results of inlet, combustor, and nozzle component tests, free-jet engine tests, analytical techniques developed to analyze and predict component and engine performance, and flight-weight hardware development are presented. These results show that efficient scramjet propulsion is attainable in a variety of flight configurations with a variety of fuels. Since the scramjet is the most efficient engine cycle for hypersonic flight within the atmosphere, it should be given serious consideration in future propulsion schemes.

Leingang, J. L.↗