clc
close all
clear 

% All data for Piper Cherokee PA-28-180
h = 1200;
V = 50;
S = 15;
m = 1090;
Ixx = 1300; Izz = 1400;  Ixz = 0; Iyy = 1700; 
CL0 = 0.543; CD0 = 0.0615;
b = 9.11;
cbar = 1.3;

Ue = V;

g = 9.80665;

Xu = -0.06728;Zu = -0.396;Mu = 0.0;
Xw = 0.02323;Zw = -1.729;Mw = -0.2772;
Xq = 0.0;Zq = -1.6804;Mq = -2.207;
Mdw = -0.0197;Zde = -17.01;Mde = -44.71;

Yv = -0.1444;Lv = -0.1166;Nv = 0.174;
Lp = -2.283;Np = -1.732;
Lr = 1.053;Nr = -1.029;
Ydr = 2.113;Ldr = 0.6133;Ndr = -6.583;
Lda = 3.101; Nda = 0.0;


% Determine the M* derivatives (Theta_e = 0)
Mu_star = Mu + Mdw*Zu;
Mw_star = Mw + Mdw*Zw;
Mq_star = Mq + Mdw*Ue;
Mth_star = 0;
Mde_star = Mde + Mdw*Zde;

% Create the system stability matrix
A = [Xu Xw 0 -g; ...
    Zu Zw Ue 0; ...
    Mu_star Mw_star Mq_star Mth_star; ...
    0 0 1 0];

% Make the input matrix, for good measure
B = [0 Zde Mde_star 0]';

% Determine the eigenvalues numerically
[V,D] = eig(A);

disp(diag(D))