Which of the following documents is issued by the FAA to approve alterations in Aircraft Type Design?

The Supplemental Type Certificates (STC) are specifically issued by the FAA to approve alterations in aircraft type design. An STC allows for changes to the original type design of an aircraft, which may include modifications or installations that were not originally part of the FAA-approved design. This regulatory process helps ensure that any alterations comply with safety and operational standards set by the FAA, thus maintaining safe aircraft operation.

STCs are essential because they provide a formal mechanism for aircraft owners and operators to legally modify their aircraft while ensuring they adhere to required safety and performance standards. They are critical for maintaining the airworthiness of the aircraft after modifications are made, allowing for the integration of new technologies, equipment, or features that may enhance functionality or safety.

Other options, like Aircraft Maintenance Records and Manufacturers Service Bulletins, serve different purposes. Maintenance records document the history of maintenance work performed on an aircraft, while service bulletins provide information and recommendations from manufacturers regarding specific issues or upgrades but do not constitute formal approval for design changes. Wiring diagrams are technical documents that illustrate the electrical systems and configurations but do not pertain to the approval process for alterations in the aircraft’s type design.