Urban railways are an important part of China’s rail transit “four network
integration”. Their stations are typically situated in suburban regions,
characterized by long lines and large station spacing. Traditional manual
inspections entail a substantial workload and exhibit low efficiency;
multi-rotor UAVs are constrained by limited endurance and airspeed, leading to
low efficiency in daily long - range inspections. Fixed-wing UAVs have the
advantages of long endurance and high altitude, and are more cost-effective for
daily routine inspections when deployed in long areas. They complement the
functions of multi-rotor UAVs in rail transit inspection applications. The
flight control system of a fixed-wing UAV is a multi-channel, strongly coupled
complex system. Based on its lateral and longitudinal dynamic models and
navigation technology, this paper designs different types of
PID control strategies for the control channels, such as
roll angle, pitch angle, altitude, vertical velocity, and flight airspeed, and
verifies the feasibility of the control algorithm through numerical simulation.
Finally, through on-site test flights, the stability and reliability of the
single aircraft flight control system were verified, providing technical support
for the availability of fixed-wing unmanned aerial vehicles in the inspection of
long sections of urban railways.