14 CFR § 21.195

A manufacturer of aircraft manufactured within the United States may apply for an experimental airworthiness certificate for an aircraft that is to be used for market surveys, sales demonstrations, or customer crew training.

A manufacturer of an aircraft engine manufactured by him within the United States, that has altered a type certificated aircraft by installing an engine it has manufactured, may apply for an experimental airworthiness certificate for that aircraft to be used for market surveys, sales demonstrations, or customer crew training, if the basic aircraft, before alteration, was type certificated in the normal, utility, acrobatic, commuter, transport, primary, or restricted category.

A person who has altered the design of a type certificated aircraft may apply for an experimental airworthiness certificate for an altered aircraft to be used for market surveys, sales demonstrations, or customer crew training, if the basic aircraft, before alteration, was type certificated in the normal, utility, acrobatic, commuter, transport, primary, or restricted category.

An applicant for an experimental airworthiness certificate under paragraph (a), (b), or (c) of this section is entitled to that certificate if, in addition to meeting the requirements of § 21.193—

He has established an inspection and maintenance program for the continued airworthiness of the aircraft; and

The applicant shows that the aircraft has been flown for at least 50 hours, or for at least 5 hours if it is a type certificated aircraft which has been altered. FAA may reduce these operational requirements if the applicant provides adequate justification.