---
kind: "section"
citation: "14 C.F.R. § 29.1027"
title: "14"
number: "29.1027"
heading: "Transmission and gearboxes: general."
url: "https://uscodex.org/cfr/14/29.1027"
---

# §29.1027. Transmission and gearboxes: general.

- (a) The oil system for components of the rotor drive system that require continuous lubrication must be sufficiently independent of the lubrication systems of the engine(s) to ensure—
  - (1) Operation with any engine inoperative; and
  - (2) **Safe autorotation.**
- (b) Pressure lubrication systems for transmissions and gearboxes must comply with the requirements of [§§ 29.1013](/cfr/14/29.1013.md), paragraphs [(c)](#c), (d), and (f) only, 29.1015, 29.1017, 29.1021, 29.1023, and 29.1337(d). In addition, the system must have—
  - (1) **An oil strainer or filter through which all the lubricant flows, and must—**
    - (i) Be designed to remove from the lubricant any contaminant which may damage transmission and drive system components or impede the flow of lubricant to a hazardous degree; and
    - (ii) **Be equipped with a bypass constructed and installed so that—**
      - (A) The lubricant will flow at the normal rate through the rest of the system with the strainer or filter completely blocked; and
      - (B) The release of collected contaminants is minimized by appropriate location of the bypass to ensure that collected contaminants are not in the bypass flowpath;
    - (iii) Be equipped with a means to indicate collection of contaminants on the filter or strainer at or before opening of the bypass;
  - (2) For each lubricant tank or sump outlet supplying lubrication to rotor drive systems and rotor drive system components, a screen to prevent entrance into the lubrication system of any object that might obstruct the flow of lubricant from the outlet to the filter required by [paragraph (b)(1)](#b-1) of this section. The requirements of [paragraph (b)(1)](#b-1) of this section do not apply to screens installed at lubricant tank or sump outlets.
- (c) Splash type lubrication systems for rotor drive system gearboxes must comply with §§ [29.1021](/cfr/14/29.1021.md) and [29.1337(d)](/cfr/14/29.1337.md?p=d).

## Notes

### Amendments

[Amdt. 29-26, 53 FR 34218, Sept. 2, 1988]

### Authority

Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704.

### Source

Source: Docket No. 5084, 29 FR 16150, Dec. 3, 1964, unless otherwise noted.

### Amendments

[Amdt. 29-26, 53 FR 34218, Sept. 2, 1988]