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The Influence of Variable Air Density and of Nonlinear Aerodynamic Characteristics on Dynamic Behavior at Supersonic Speeds


Oswald, Telford Wilbert (1951) The Influence of Variable Air Density and of Nonlinear Aerodynamic Characteristics on Dynamic Behavior at Supersonic Speeds. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/VG6Q-C753.


The effect of the variable density of the Standard Atmosphere on the dynamic stability of a missile in vertical flight is considered. The analysis is restricted to small disturbances from steady rectilinear flight. The exponential decrease of density with altitude characteristic of the Standard Stratosphere is introduced into the equations of motion and a stability criterion for the dynamic behavior immediately following a small disturbance is found. Alternatively, a hyperbolic variation of density with altitude is used to approximate the Standard Atmosphere and the identical stability criterion is obtained. The effect of non-linear pitching moment and lift variations with angle of attack on the dynamic response to a sudden change in angle of attack is considered. An approximate solution to the non-linear equation of motion is developed. Several numerical examples are considered, and the results of the approximate solution are compared with the very accurate results of numerical integration as well as the classical linearized solution. The effect of a non-linear moment curve on the determination of stability derivatives from flight test data is discussed in the light of these examples.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:(Aeronautics and Mathematics)
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Aeronautics
Minor Option:Mathematics
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Millikan, Clark Blanchard
Thesis Committee:
  • Unknown, Unknown
Defense Date:1 January 1951
Record Number:CaltechETD:etd-02242006-160420
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:738
Deposited By: Imported from ETD-db
Deposited On:27 Feb 2006
Last Modified:24 Apr 2023 22:37

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