Accession Number:

AD0259475

Title:

THE STATIC STABILITY OF GROUND EFFECT VEHICLES - THIN JET THEORY

Descriptive Note:

Technical rept.,

Corporate Author:

HYDRONAUTICS INC LAUREL MD

Personal Author(s):

Report Date:

1960-12-01

Pagination or Media Count:

1.0

Abstract:

A theoretical study of the static pitch stability of simple types of thin jet ground effect machines, including the influence of interior jets, is presented. Some simplifications and assumptions are made but these are kept to a minimum. Tulins treatment of underfed and overfed jets is used and extended here to take into account the jet flow under the machine. In the expression for the pitching moment, certain nonlinearities are included. The importance of various physical parameters for pitch static stability is calculated and discussed. Two-dimensional machines tend to be unstable at all altitudes except possibly very close to the ground. The use of interior jets stabilizes the machine markedly stability increasing with decreasing altitude. Increasing the stability generally results in decreased powering efficiency. The general behavior of three-dimensional machines is similar to that of the corresponding two-dimensional machines but with some improvement in stability. Charts are presented to allow the rapid estimation of the static pitch stability of simple machines. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE