14 CFR § 135.417 - Mechanical interruption summary report.
---
identifier: "/us/cfr/t14/s135.417"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "14 CFR § 135.417 - Mechanical interruption summary report."
title_number: 14
title_name: "Aeronautics and Space"
section_number: "135.417"
section_name: "Mechanical interruption summary report."
chapter_name: "FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "G"
subchapter_name: "AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS"
part_number: "135"
part_name: "OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 106(f), 40113, 41706, 44701-44702, 44705, 44709, 44711-44713, 44715-44717, 44722, 44730, 45101-45105; Pub. L. 112-95, 126 Stat. 58 (49 U.S.C. 44730)."
regulatory_source: "Docket 16097, 43 FR 46783, Oct. 10, 1978, unless otherwise noted."
cfr_part: "135"
---
# 135.417 Mechanical interruption summary report.
Each certificate holder shall mail or deliver, before the end of the 10th day of the following month, a summary report of the following occurrences in multiengine aircraft for the preceding month to the responsible Flight Standards office:
(a) Each interruption to a flight, unscheduled change of aircraft en route, or unscheduled stop or diversion from a route, caused by known or suspected mechanical difficulties or malfunctions that are not required to be reported under § 135.415.
(b) The number of propeller featherings in flight, listed by type of propeller and engine and aircraft on which it was installed. Propeller featherings for training, demonstration, or flight check purposes need not be reported.
[Docket 16097, 43 FR 46783, Oct. 10, 1978, as amended by Amdt. 135-60, 61 FR 2616, Jan. 26, 1996; Docket FAA-2018-0119, Amdt. 135-139, 83 FR 9175, Mar. 5, 2018]