FAR 21.35 — Type Certificate Flight Tests
FAR 21.35 explains the flight tests required for an aircraft type certificate, including prerequisites, crew safety, and minimum operating hours.
In Plain English
FAR 21.35 sets the flight test requirements an applicant must complete to earn an aircraft type certificate. While this rule is aimed at manufacturers rather than individual pilots, it's useful background for understanding how the airplanes you fly were certificated.
Before flight tests begin, the applicant must show:
- Compliance with applicable structural requirements
- Completion of necessary ground inspections and tests
- That the aircraft conforms to the type design
- That the FAA has received a signed flight test report
Once those prerequisites are met, the applicant must conduct any flight tests the FAA finds necessary to verify regulatory compliance and, for most aircraft, to give reasonable assurance that the aircraft, components, and equipment are reliable and function properly.
Key operational points:
- Adequate provisions must be made for emergency egress and parachutes (except gliders and manned free balloons).
- Testing must stop if the test pilot can't or won't perform a test, or if noncompliance makes further testing meaningless or unsafe.
- Minimum flight hours: 300 hours for aircraft with new turbine engines, 150 hours for all others.
Regulation Text
14 CFR § 21.35§ 21.35 Flight tests.
(a) Each applicant for an aircraft type certificate (other than under §§ 21.24 through 21.29) must make the tests listed in paragraph (b) of this section. Before making the tests the applicant must show—
(1) Compliance with the applicable structural requirements of this subchapter;
(2) Completion of necessary ground inspections and tests;
(3) That the aircraft conforms with the type design; and
(4) That the FAA received a flight test report from the applicant (signed, in the case of aircraft to be certificated under Part 25 [New] of this chapter, by the applicant's test pilot) containing the results of his tests.
(b) Upon showing compliance with paragraph (a) of this section, the applicant must make all flight tests that the FAA finds necessary—
(1) To determine compliance with the applicable requirements of this subchapter; and
(2) For aircraft to be certificated under this subchapter, except gliders and low-speed, certification level 1 or 2 airplanes, as defined in part 23 of this chapter, to determine whether there is reasonable assurance that the aircraft, its components, and its equipment are reliable and function properly.
(c) Each applicant must, if practicable, make the tests prescribed in paragraph (b)(2) of this section upon the aircraft that was used to show compliance with—
(1) Paragraph (b)(1) of this section; and
(2) For rotorcraft, the rotor drive endurance tests prescribed in § 27.923 or § 29.923 of this chapter, as applicable.
(d) Each applicant must show for each flight test (except in a glider or a manned free balloon) that adequate provision is made for the flight test crew for emergency egress and the use of parachutes.
(e) Except in gliders and manned free balloons, an applicant must discontinue flight tests under this section until he shows that corrective action has been taken, whenever—
(1) The applicant's test pilot is unable or unwilling to make any of the required flight tests; or
(2) Items of noncompliance with requirements are found that may make additional test data meaningless or that would make further testing unduly hazardous.
(f) The flight tests prescribed in paragraph (b)(2) of this section must include—
(1) For aircraft incorporating turbine engines of a type not previously used in a type certificated aircraft, at least 300 hours of operation with a full complement of engines that conform to a type certificate; and
(2) For all other aircraft, at least 150 hours of operation.
[Doc. No. 5085, 29 FR 14564, Oct. 24, 1964, as amended by Amdt. 21-40, 39 FR 35459, Oct. 1, 1974; Amdt. 21-51, 45 FR 60170, Sept. 11, 1980; Amdt. 21-70, 57 FR 41368, Sept. 9, 1992; Amdt. 21-95, 76 FR 64233, Oct. 18, 2011; Doc. No. FAA-2015-1621, Amdt. 21-100, 81 FR 96689, Dec. 30, 2016]
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Oral Exam Questions a DPE Might Ask
Q1What must an applicant demonstrate before beginning the flight tests required for a type certificate?
Per FAR 21.35(a), the applicant must show compliance with applicable structural requirements, completion of necessary ground inspections and tests, conformity with the type design, and submission of a signed flight test report to the FAA.
Q2How many flight test hours are required under FAR 21.35 for type certification?
FAR 21.35(f) requires at least 300 hours of operation for aircraft with turbine engines of a type not previously used in a type-certificated aircraft, and at least 150 hours for all other aircraft.
Q3Under what conditions must flight testing be discontinued during type certification?
FAR 21.35(e) requires testing to stop until corrective action is taken if the test pilot is unable or unwilling to perform required tests, or if items of noncompliance are found that would make further test data meaningless or testing unduly hazardous.
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§21.15 Type Certificate Application
FAA application form, aircraft drawings, and engine data
§21.17 Certification Basis
Applicable airworthiness, noise, and emission rules
§21.20 Compliance Showing
How applicants show compliance to the FAA
§21.31 Type Design
Drawings, specifications, dimensions, and limitations
§21.41 Type Certificate
What the certificate includes once the design is approved
§21.47 Type Certificate Transferability
Transfer and licensing notices for FAA type certificates
Related Sections in Part 21