function [a,b,c,d]=b1l
%b1l 	Creates linearized state space model of a Boeing 707-321 aircraft
%	at v=80m/s. (M = 0.26, Ga0 = -3 deg, alpha0 = 4 deg, kappa = 50 deg)
%
%	FORMAT:		[a,b,c,d]=b1l
%
%	Matrix D may be omitted.
%	System inputs are  (1) thrust   and (2) elevator angle
%	System outputs are (1) airspeed and (2) pitch angle
%
%	RELATED OPERATIONS:	PT2

%	K P Mueller 09-JUL-1991
%	Copyright (c) 1991, by IfR

error(nargchk(0,0,nargin));
error(nargchk(3,4,nargout));

a = [ -0.46E-01                0.10681415316     0.0    -0.17121680433    
      -0.1675901504661613     -0.515             1.0     0.6420630320636088E-02
       0.1543104215347786     -0.547945         -0.906  -0.1521689385990753E-02
       0.0                     0.0               1.0     0.0 ];

b = [ 0.1602300107479095       0.2111848453E-02
      0.8196877780963616E-02  -0.3025E-01
      0.9173594317692437E-01  -0.75283075   
      0.0                      0.0 ];

c = [ 1.0                      0.0               0.0    0.0
      0.0                      0.0               0.0    1.0 ];

if nargout == 4,
d = zeros(2);
end
