REGULATION — LEGALLY BINDING

§ 91.411 Altimeter system and altitude reporting equipment tests and inspections

14 CFR Part 91 — Subpart E—Maintenance, Preventive Maintenance, and Alterations

Official text — 14 CFR § 91.411

REGULATION — LEGALLY BINDING

(a) No person may operate an airplane, or helicopter, in controlled airspace under IFR unless—

(1) Within the preceding 24 calendar months, each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system has been tested and inspected and found to comply with appendices E and F of part 43 of this chapter;

(2) Except for the use of system drain and alternate static pressure valves, following any opening and closing of the static pressure system, that system has been tested and inspected and found to comply with paragraph (a), appendix E, of part 43 of this chapter; and

(3) Following installation or maintenance on the automatic pressure altitude reporting system of the ATC transponder where data correspondence error could be introduced, the integrated system has been tested, inspected, and found to comply with paragraph (c), appendix E, of part 43 of this chapter.

(b) The tests required by paragraph (a) of this section must be conducted by—

(1) The manufacturer of the airplane, or helicopter, on which the tests and inspections are to be performed;

(2) A certificated repair station properly equipped to perform those functions and holding—

(i) An instrument rating, Class I;

(ii) A limited instrument rating appropriate to the make and model of appliance to be tested;

(iii) A limited rating appropriate to the test to be performed;

(iv) An airframe rating appropriate to the airplane, or helicopter, to be tested; or

(3) A certificated mechanic with an airframe rating (static pressure system tests and inspections only).

(c) Altimeter and altitude reporting equipment approved under Technical Standard Orders are considered to be tested and inspected as of the date of their manufacture.

(d) No person may operate an airplane, or helicopter, in controlled airspace under IFR at an altitude above the maximum altitude at which all altimeters and the automatic altitude reporting system of that airplane, or helicopter, have been tested.

Reproduced from the eCFR. Text as amended through 2026-07-31. Verify against the official source before relying on it operationally.

SkeyeMentor explanation

Educational — not an FAA source

In plain English

The tests and inspections required for the altimeter system, altitude reporting equipment and static pressure system before operating in controlled airspace under IFR.

Why it matters

It applies only to IFR operations in controlled airspace, which distinguishes it from the transponder test in 91.413.

Quick example

State the interval in paragraph (a) and compare it with 91.413.

Written and reviewed by the SkeyeMentor editorial team. This explanation is a study aid, not legal advice, and it is not part of the official text above. Verify current requirements through the official source before relying on them operationally.

Is this a regulation?

Yes — this is regulatory text and is legally binding.

Text published in the Code of Federal Regulations. Regulations are legally binding on pilots and operators.

Yes — this is the text of a Federal Aviation Regulation. It is legally binding. The explanation below it is SkeyeMentor educational content, not part of the regulation.

SkeyeMentor FAA Library is an educational reference and study aid. Regulatory and FAA materials can change. SkeyeMentor provides links and contextual explanations to help pilots study, but users should verify current requirements through official FAA, eCFR and other applicable government sources before relying on them operationally. SkeyeMentor explanations are educational and are not legal advice.