# 14 CFR § 27.1309: Equipment, systems, and installations

> Federal · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1309

## Section

- **Citation:** 14 CFR § 27.1309
- **Heading:** Equipment, systems, and installations
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** September 22, 2026
- **Source:** Publisher's official text
- **Location:** Title 14—Aeronautics and Space > CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION > SUBCHAPTER C—AIRCRAFT > PART 27—AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT > Subpart F—Equipment > General

## Text

The equipment, systems, and installations whose functioning is required by this subchapter must be designed and installed to ensure that they perform their intended functions under any foreseeable operating condition. For any item of equipment or system whose failure has not been specifically addressed by another requirement in this chapter, the following requirements also apply:
(a) The design of each item of equipment, system, and installation must be analyzed separately and in relation to other rotorcraft systems and installations to determine and identify any failure that would affect the capability of the rotorcraft or the ability of the crew to perform their duties in all operating conditions.
(b) Each item of equipment, system, and installation must be designed and installed so that:
(1) The occurrence of any catastrophic failure condition is extremely improbable;
(2) The occurrence of any major failure condition is no more than improbable; and
(3) For the occurrence of any other failure condition between major and catastrophic, the probability of the failure condition must be inversely proportional to its consequences.
(c) A means to alert the crew in the event of a failure must be provided when an unsafe system operating condition exists and to enable them to take corrective action. Systems, controls, and associated monitoring and crew alerting means must be designed to minimize crew errors that could create additional hazards.
(d) Compliance with the requirements of this section must be shown by analysis and, where necessary, by ground, flight, or simulator tests. The analysis must account for:
(1) Possible modes of failure, including malfunctions and misleading data and input from external sources;
(2) The effect of multiple failures and latent failures;
(3) The resulting effects on the rotorcraft and occupants, considering the stage of flight and operating conditions; and
(4) The crew alerting cues and the corrective action required.
[Amdt. 27-51, 88 FR 8737, Feb. 10, 2023]

## Nearby sections

- [14 CFR § 27.1301 § 27.1301 Function and installation.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1301.md)
- [14 CFR § 27.1303 § 27.1303 Flight and navigation instruments.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1303.md)
- [14 CFR § 27.1305 § 27.1305 Powerplant instruments.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1305.md)
- [14 CFR § 27.1307 § 27.1307 Miscellaneous equipment.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1307.md)
- [14 CFR § 27.1309 § 27.1309 Equipment, systems, and installations.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1309.md)
- [14 CFR § 27.1316 § 27.1316 Electrical and electronic system lightning protection.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1316.md)
- [14 CFR § 27.1317 § 27.1317 High-intensity Radiated Fields (HIRF) Protection.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1317.md)
- [14 CFR § 27.1321 § 27.1321 Arrangement and visibility.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1321.md)
- [14 CFR § 27.1322 § 27.1322 Warning, caution, and advisory lights.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1322.md)
- [14 CFR § 27.1323 § 27.1323 Airspeed indicating system.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1323.md)
- [14 CFR § 27.1325 § 27.1325 Static pressure systems.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1325.md)
- [14 CFR § 27.1327 § 27.1327 Magnetic direction indicator.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1327.md)
- [14 CFR § 27.1329 § 27.1329 Automatic pilot and flight guidance system.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1329.md)
- [14 CFR § 27.1337 § 27.1337 Powerplant instruments.](https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1337.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/ecfr-14-27.1309. Check the current official text before relying on it. Not legal advice.