Aircraft with wing loading of 9 lb/square ft and over should have fabric strength at or above ___________?

For aircraft with a wing loading of 9 pounds per square foot and greater, it is essential to ensure that the fabric used in the covering meets specific strength criteria to maintain structural integrity and safety during operation. Grade A fabric is designed to provide the necessary strength for higher wing loading scenarios, offering durability and resilience against varying flight conditions.

Choosing a fabric that meets or exceeds the Grade A specification ensures that it can withstand the stresses encountered in flight, such as aerodynamic forces and impacts. The proper fabric strength is critical in ensuring that the aircraft can perform as intended without risking structural failure. Hence, for wing loading at or above 9 lb/square ft, the requirement for the fabric strength is to be at or above Grade A, supporting the safe operation of the aircraft.