If a person alters an aircraft by installing special wing tips, what type of approval is needed to duplicate this alteration on other aircraft?

The correct response is that a Supplemental Type Certificate (STC) is required to duplicate an alteration like installing special wing tips on other aircraft. An STC is specifically designed for changes made to the original design of an aircraft that enhance its performance, functionality, or aesthetic qualities. When an alteration is made that affects the aircraft's type design, obtaining an STC ensures that this modification complies with Federal Aviation Administration (FAA) regulations and safety standards.

In the case of special wing tips, these modifications could potentially affect the aircraft's aerodynamics and overall safety. Therefore, the approval through an STC is necessary to document the change and establish that it has been tested and validated for use across other similar aircraft. This process helps maintain safety and compliance within the aviation industry by requiring that any significant alterations are properly certified and documented.

The other options, while related to the certification of aircraft, serve different purposes. A Provisional Type Certificate is used for new aircraft designs during their development phase but does not apply to alterations on existing aircraft. A Production Certificate is related to the production of aircraft and their parts, ensuring quality control during manufacturing rather than modifications. A Type Certificate is for validating the original design of an aircraft rather than alterations. Thus, an ST