Temperature Gradients in the Wing of a High-Speed Airplane During Dives from High Altitudes
Abstract
Flight tests were undertaken to investigate the temperature gradients in the wing structure of a typical high-speed fighter airplane caused by rapid changes in surface temperatures. The tests consisted of measuring the temperatures of the structure throughout the wing (during dives of the airplane from 35000 to 5000 ft, at rates of vertical descent up to 225 ft/sec. The data are presented in the form of tables of the measured temperatures and plots of the temperature change of typical parts of the wing structure during the dives. The tests showed that temperature gradients which are produced in an aircraft structure as a result of sudden changes in surface temperature are essentially a transient condition and, therefore, are determined mainly by the relative size of adjacent structural members, the thermal bond between these members, and the rate of change of surface temperature. Predicted and measured temperature differences between a spar cap and the adjacent skin in dives showed good agreement, and it is believed that the method used for predicting temperature gradients may be applied to other airplanes and dive conditions. Computations were made to show the effects of increases in (1) the rate of descent, and (2) structural mass distribution (thermal capacity) on the temperature distribution for dives at higher speeds. It was shown that a structural design employing a thin wing skin attached to a heavy spar cap is conclusive to severe temperature gradients.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1948
- Accession Number
- ADA380742
Entities
People
- Bernard A. Schlaff
- Thorval Tendeland
Organizations
- National Aeronautics and Space Administration