Which part of the FARs specifies the performance characteristics for small aircraft to be considered airworthy?

The performance characteristics for small aircraft to be considered airworthy are specified under FAR Part 23. This part of the Federal Aviation Regulations (FARs) contains the airworthiness standards for normal, utility, acrobatic, and commuter category airplanes. It defines the design and safety requirements that an aircraft must meet to be deemed airworthy, ensuring that small aircraft can be operated safely.

FAR Part 25, on the other hand, pertains to the airworthiness standards for transport category aircraft, which are larger and more complex than the small aircraft covered under Part 23. FAR Part 21 deals with the certification procedures for products and parts but does not specifically address performance characteristics or airworthiness standards in detail. FAR Part 43 covers the maintenance, preventive maintenance, rebuilding, and alteration of aircraft, which is separate from the initial performance standards established for airworthiness.

Thus, FAR Part 23 is the relevant regulation that outlines the necessary performance characteristics to determine the airworthiness of small aircraft, making it the correct choice in this context.