Who determines the fabric type and strength requirements for fabric-covered aircraft?

The aircraft manufacturer is responsible for determining the fabric type and strength requirements for fabric-covered aircraft. This is critical as manufacturers design their aircraft to meet specific performance, safety, and regulatory standards. They conduct extensive testing and engineering analysis to decide on the appropriate materials that are suitable for different parts of the aircraft, taking into account factors like weight, durability, environmental conditions, and airworthiness criteria.

These specifications are then outlined in the aircraft's documentation, such as maintenance manuals and the type certificate data sheet. The data provided ensures that any repairs or recoveries done on the aircraft conform to the original design standards and maintain the integrity and safety of the aircraft.

While regulations from the aviation authority may set overall safety standards, the specific fabric requirements originate from the manufacturer's decisions based on the aircraft's design needs. This creates a direct link between the manufacturer's specifications and the materials used, ensuring compliance with safety and performance standards during operations.