Stability analysis of a Boeing 737-800

The Anthena Vortex Lattice (AVL) [1] program describes aerodynamic and flight-dynamic analysis of rigid aircraft of arbitrary configuration and we use it to analyse the stability modes of a Boeing 737-800 under various small perturbations about trimmed equilibrium. We perturb the aircraft's free-stream velocity, its banking angle, its mass (which can be considered in conditions such as fuel dumping) and also analyse how it behaves at different heights (different air densities). We then compute the time it takes the various stability modes to return to equilibrium and show that this time obeys the logistic growth model for the Dutch roll and Short period mode when the velocity is perturbed and when varying the height above sea level of the aircraft.