Theoretical and Analog Studies of the Effects of Nonlinear Stability Derivatives on the Longitudinal Motions of an Aircraft in Response to Step Control Deflections and to the Influence of Proportional Automatic Control by United States. National Advisory Committee for Aeronautics, Stuart C. Brown, Howard J. Curfman, Benjamin Milwitzky, George E. Solomon, George E. Towe, Morris Morduchow, P. S. Klebanoff, Stanley Corrsin, William C. Triplett, Alan L. Kistler, Dean C. Lindquist, Henry J. Gomberg, Dexter M. Potter, G. Allan Smith, J. W. Freeman