Gulfstream filed a patent last week for a new undercarriage configuration that significantly reduces the amount of noise created when an aircraft flies with the landing gear deployed. As engines have become ever quieter, the aerodynamic noise created by disturbed airflow around the aircraft itself makes up an increasing proportion of the overall noise signature.
In landing configuration one of the biggest culprits is the landing gear, the nosewheel in particular. The non-streamlined shape of the landing gear creates a lot of airflow disturbance, and therefore a high degree of noise.
Gulfstream’s new system reduces noise by placing the torque arm assembly ahead of the shock strut, where it encounters smooth air rather than “flying” in the disturbed air behind. Designed to have a streamlined profile, the torque arm assembly provides a natural shield for the shock strut behind it, creating smoother airflow around the nosewheel.
The company’s patent also depicts a shielding surface that curves under the central hub of the wheel, closing the gap between the twin nosewheels and further smoothing airflow around the wheel assembly.