A Comparative Analysis of Longitudinal and Lateral Directional Dynamics of Aircraft from Different Classes

The comparative study and analysis of five different aircrafts namely, Cessna 182 (Class I), Beech 99 (Class II), Cessna T37A (Class II), Boeing 747 200 (Class III), McDonnell Douglas F4 (Class IV) at different flight conditions is presented in this paper. The mathematical model and dynamic characteristics of a generic aircraft is simulated, where some assumptions are made while deriving the models. The aircraft dynamic characteristics are derived as MATLAB functions and simulated. It gives full 6DoF aircraft mathematical modelling using Euler angles, trimming at desired flight conditions and generation of linearized model. Simulation results shows that the stability of longitudinal/lateral directional dynamics depends on the aircraft geometric parameters, inertial characteristics and flight conditions. Greater the value of ω_NSP, higher the airspeed, resulting in faster dynamics of short period mode. As the altitude decreases, magnitude of ω_NSP also decreases with increase in air density. The aircraft of lower size and weight associated with smaller value of I_yy leads to greater value of ω_NSP. At low subsonic flight conditions (high values of C_L1, low values for C_Du) the value of ζ_PH is less as compared to the aircraft at higher subsonic conditions (lower values of C_L1, higher values for C_Du).