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James, R. L., Jr.

Publications and source records attributed to James, R. L., Jr..

Airframe technology for aircraft energy efficiency

The economic factors that resulted in the implementation of the aircraft energy efficiency program (ACEE) are reviewed and airframe technology elements including content, progress, applications, and future direction are discussed. The program includes the development of laminar flow systems, advanced aerodynamics, active controls, and composite structures.

James, R. L., Jr.

The drive for Aircraft Energy Efficiency

NASA's Aircraft Energy Efficiency (ACEE) program, which began in 1976, has mounted a development effort in four major transport aircraft technology fields: laminar flow systems, advanced aerodynamics, flight controls, and composite structures. ACEE has explored two basic methods for achieving drag-reducing boundary layer laminarization: the use of suction through the wing structure (via slots or perforations) to remove boundary layer turbulence, and the encouragement of natural laminar flow maintenance through refined design practices. Wind tunnel tests have been conducted for wide bodied aircraft equipped with high aspect ratio supercritical wings and winglets. Maneuver load control and pitch-active stability augmentation control systems reduce fuel consumption by reducing the drag associated with high aircraft stability margins. Composite structures yield lighter airframes that in turn call for smaller wing and empennage areas, reducing induced drag for a given payload. In combination, all four areas of development are expected to yield a fuel consumption reduction of 40 percent.

James, R. L., Jr.

Large space systems technology program

Technical challenges of shuttle-era large space systems include the development of space-configured spacecraft concepts, compatibility with the space transportation system, and cost effectiveness. The objectives and organization of NASA's large space structures program are outlined and program elements are discussed. The technology for the offset wrap-rip and the maypole (hoop/column) antenna concepts are discussed as well as analysis techniques for predicting the electromagnetic performance of a broad class of large reflectors. Deployable systems, assembly methods, and modular control systems for space platforms are described. Assembly equipment and devices, surface sensors and shape control, control and stabilization, and integrated analysis and design are also considered.

James, R. L., Jr.