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Jackson, L. R.

Publications and source records attributed to Jackson, L. R..

46 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

The case for a high-speed research airplane - Results from an in-house study

Results of a study aimed at determining the feasibility of developing a single versatile high-speed research airplane (HSRA) which will meet flight research needs of both Mach 3 to 5 JP-fueled military aircraft and of hydrogen-fueled aircraft, both military and civil, for speeds up to Mach 10. The proposed HSRA design concept is an air-launched, rocket-boosted research aircraft designed to accommodate a wide variety of large-scale propulsive and structural flight research experiments. The aircraft is a 60-foot-long discrete wing-body concept with high wings and a center-line vertical tail. Heat sink shields are proposed as an effective and versatile method of achieving low-cost, low-risk thermal protection of the all-aluminum primary structure.-

Kirkham, F. S.↗
NASA NTRS1972

Optimum mass-strength analysis for orthotropic ring-stiffened cylinders under axial compression

An analysis was developed to calculate the minimum mass-strength curve for an orthotropic cylinder subjected to axial compressive loading. The analysis, which includes the effects of ring and stringer eccentricities, is in a general form so that various cylinder wall and stiffener geometries can be considered. Several different ring-stiffened orthotropic configurations were studied. The minimum mass-strength curves and the dimensions associated with these curves are presented for (in order of decreasing efficiency) a tubular double bead, a nonsymmetric double bead, a Z-stiffened skin, and a trapezoidal corrugation. A comparison of efficiencies of the configurations shows a tubular element cylinder to be more efficient than a 3-percent core-density honeycomb-sandwich cylinder. It was found that for an optimized Z-stiffened skin, the location of the Z-stiffeners (internal or external) made a negligible difference in efficiency.

Shideler, J. L.↗
NASA NTRS1959

Fatigue Strengths of Aircraft Materials: Axial-Load Fatigue Tests on Edge-Notched Sheet Specimens of 2024-T3 and 7075-T6 Aluminum Alloys and of SAE 4130 Steel with Notch Radii of 0.004 and 0.070 inch

The present report gives results of axial-load fatigue tests on notched specimens of three sheet materials: 2024-T3 and 7075-T6 aluminum alloys and normalized SAE 4130 steel. Two edge-notched specimens were designed and tested, each having a theoretical stress-concentration factor K(sub t) = 4.0. The radii of the notches were 0.004 and 0.070 inch. Tests of these specimens were run at two levels of nominal mean stress: 0 and 20,000 psi. Results of these studies extended information previously reported on tests of specimens with varying notch severity. They afford data on the variation of fatigue-strength reduction with notch radius and on the potential usefulness of Neuber's technical stress-concentration factor K(sub n).

Grover, H. J.↗