Accession Number:

ADA064882

Title:

Studies of Limb-Dislodging Forces Acting on an Ejection Seat Occupant.

Descriptive Note:

Final rept. 1 Mar 77-28 Feb 78,

Corporate Author:

VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG DEPT OF ENGINEERING SCIENCE AND MECHANICS

Personal Author(s):

Report Date:

1979-01-01

Pagination or Media Count:

41.0

Abstract:

In this report, the forces tending to dislodge the limbs of an ejection seat occupant from one another, or from a restraining surface, are calculated in the absence of flow separation. For a simulated ejection taking place at an altitude of 10,000 feet, the results show that, based on published data for a pilots average grip retention capability, the probability of his letting go is 100 if the ejection occurs at Mach numbers exceeding 0.72. Moreover, the probability of major flail injury is around 100 if the ejection Mach number exceeds around 1.25. One major factor which contributes to these large limb-dislodging forces is the generation of stagnation points in the flow. In order to examine further the role played by flow separation around the blunt body segments, a complex velocity potential is developed to describe a stationary vortex pair located in the wake region of the flow. It remains to super-impose this vortex pair on the unseparated cross flow in order to ascertain the drag forces which contribute to limb-dislodgement. Author

Subject Categories:

  • Aircraft
  • Fluid Mechanics
  • Escape, Rescue and Survival

Distribution Statement:

APPROVED FOR PUBLIC RELEASE