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United States Department of Transportation United States Department of Transportation

AC 21-50 - Installation of TSOA Articles and LODA Appliances

Document Information

Installation of TSOA Articles and LODA Appliances
Date issued
Office of Primary Responsibility

Describes what you, as an installer, must show in a data package that is presented to the Federal Aviation Administration (FAA) through either a technical standard order authorization (TSOA) or TSO letter of design approval (LODA), under the provisions of Title 14 of the Code of Federal Regulations (14 CFR) part 21. This AC does not address aircraft repairs or alterations involving TSO articles under the provisions of 14 CFR part 43, nor does it address alterations to TSOA articles by repair stations under 14 CFR part 43. For the remainder of this document, the manufacturer of these articles will be referred to as a TSOA holder. Those seeking a design approval will be referred to as applicants.

This AC is not mandatory and is not a regulation. This AC describes an acceptable means, but not the only means, to comply with the applicable requirements. However, if you use the means described in this AC, you must follow it entirely.