Airbus Copters Need Fan Leg Crack Inspections Now
Published Date: 8/13/2026
Rule
Summary
The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Model AS355E, AS355F, AS355F1, AS355F2, and AS355N helicopters. This AD was prompted by reports of cracks in the legs of the side supports of the tail rotor transmission fan. This AD requires repetitively inspecting the side supports of the tail rotor transmission fan for cracks and, depending on the results, replacing both side supports. The FAA is issuing this AD to address the unsafe condition on these products.
Analyzed Economic Effects
5 provisions identified: 1 benefits, 4 costs, 0 mixed.
Per-aircraft inspection and replacement costs
The FAA estimates each inspection takes 1.5 work-hours at $85 per hour for a cost of $128 per helicopter. If replacement is required, replacing both side supports is estimated at 24 work-hours ($2,040 labor) plus $2,640 parts, totaling $4,680 per helicopter. The FAA estimates the AD affects 34 U.S.-registered helicopters, and the inspection-only cost across those helicopters is $4,352.
Mandatory repetitive inspections required
This rule applies to all Airbus Helicopters Models AS355E, AS355F, AS355F1, AS355F2, and AS355N and requires repetitive inspections of the left- and right-hand side supports of the tail rotor transmission fan for cracks, and, if a crack is found, replacement of both side supports. The AD is effective September 17, 2026 and incorporates EASA AD 2025-0052 for required actions.
Special flight permits disallowed
The AD states that special flight permits under 14 CFR 21.197 and 21.199 are not allowed for these helicopters. Operators cannot rely on special flight permits to ferry an affected helicopter for compliance or repair under this AD.
No reporting requirement to manufacturer
Unlike the corresponding EASA AD, this FAA AD does not require operators to report inspection results to the manufacturer. The AD explicitly states there is no reporting requirement.
Small-entity economic impact estimate
The FAA states the AD affects 25 entities (13 of which are small entities) and presents a high-case cost impact to those small entities. In the high-case scenario, the AD's cost is estimated to be no greater than 1.24 percent of a small entity's annual revenue, and the FAA certified the AD will not result in a significant economic impact on a substantial number of small entities.
Personalized for You
How does this regulation affect your finances?
Personalize government policy and PRIA will tell you what this federal register document means for your household, plus every other regulation we track. PRIA reads each provision against your financial profile to show you exactly what matters to your wallet.
Key Dates
Department and Agencies
Related Federal Register Documents
2026-15585, Requirements for Interference-Tolerant Radio Altimeter Systems
In July 2025, President Trump signed the One Big Beautiful Bill Act. Section 40002 of that law re-institutes the Federal Communications Commission's general auction authority and specifically directs the Commission to complete a system of competitive bidding for not less than 100 megahertz in the 3.98-4.2 gigahertz band (Upper C- band). This final rule supports the Federal Communications Commission's July 2026 Report and Order that makes 160 megahertz of the Upper C-band available for terrestrial wireless flexible use via a system of competitive bidding. To ensure safe, efficient, and reliable aviation operations in the presence of wireless signals in the C-band, the Federal Aviation Administration is issuing new regulations that require all radio altimeters to meet specific minimum performance requirements. These new radio altimeters must withstand interference from wireless signals in neighboring spectrum bands and continue to provide accurate altitude readings to both pilots and integrated aircraft safety systems. These regulations require all aircraft equipped with radio altimeters operating under part 121 and those aircraft with radio altimeters operating under part 129 with 30 or more passenger seats or a payload capacity of more than 7,500 pounds to comply with the minimum performance requirements by December 30, 2030, which is prior to the date the Federal Communications Commission authorizes the use of the Upper C-band for new wireless services, as stated in its Report and Order. All other aircraft equipped with radio altimeters that are required to comply with part 91, including aircraft operating under parts 125, 133, 135, 136, 137, 194, and all other aircraft operating under part 129 that are not subject to the initial deadline, must comply with the same minimum performance requirements on or before October 31, 2034.
2026-13440, Enabling Supersonic Overland Flight
The FAA wants to let supersonic planes fly over land again by updating old rules that banned them because of loud sonic booms. Thanks to new tech that keeps booms quiet, this change will open the door for faster, cooler flights across the U.S., helping America lead the world in supersonic travel. People and companies interested in supersonic flight should share their thoughts by August 17, 2026.
2026-13126, Designation-Restrict the Operation of Unmanned Aircraft in Close Proximity to a Fixed Site Facility; Extension of Comment Period
The FAA is giving more time—until August 5, 2026—for people to share their thoughts on new rules that would limit drone flights near important fixed sites like power plants or airports. This affects drone operators and facility owners who want to keep the skies safe and secure. No new costs yet, just extra time to weigh in and help shape the rules.
2026-08943, Designation-Restrict the Operation of Unmanned Aircraft in Close Proximity to a Fixed Site Facility
The FAA is proposing new rules to keep drones away from certain important fixed sites like power plants or airports to keep everyone safe and secure. If you own or operate one of these sites, you can request a drone flight restriction zone to protect your property and people nearby. Comments are open until July 6, 2026, and these changes could affect drone pilots and site operators, but no big costs are expected.
2025-03853, Enforcement Policy Regarding “Drug and Alcohol Testing of Certificated Repair Station Employees Located Outside of the United States; Correction”
The FAA is giving repair stations outside the U.S. a break by delaying enforcement of new drug and alcohol testing rules until March 20, 2025. This means affected repair stations don’t have to worry about penalties if they aren’t fully following the updated rules just yet. The delay helps everyone get ready without rushing or extra costs.
2026-19891, Airworthiness Directives; MD Helicopters, LLC Helicopters
If you own or operate MD Helicopters models 369, 500N, or 600N, listen up! The FAA fixed a small mistake in a safety rule about checking and possibly replacing parts in your helicopter’s torque tube and roller bearings. This correction doesn’t change the original safety checks or costs, and it kicks in on October 20, 2026.
Previous / Next Documents
Previous: 2026-16504, Airworthiness Directives; The Boeing Company Airplanes
The FAA is superseding Airworthiness Directive (AD) 2018-11- 14, which applied to certain The Boeing Company Model 767-300 and -300F series airplanes with certain winglets installed. AD 2018-11-14 required high frequency eddy current (HFEC) inspections for cracking of the lower outboard wing skin and repair or modification if necessary. AD 2018-11-14 also required one of three follow-on actions: Repeating the HFEC inspections; modifying certain internal stringers and oversizing and plugging the existing fastener holes of the lower wing; or modifying the external doubler/tripler and doing repetitive post- modification inspections. This AD was prompted by reports of fatigue cracking in the lower outboard wing skin at the inboard fastener of stringer L-9.5, and the lower outboard wing skin of stringer L-6.5, on airplanes with winglets installed per Supplemental Type Certificate (STC) ST01920SE. This AD was also prompted by a determination that, for certain airplanes, the area of the lower wing skin in the vicinity of the critical inboard end fasteners of installed repair doublers must be inspected. This AD continues to require the actions in AD 2018-11-14, adds to the applicability airplanes that have had STC ST01920SE installed and the STC winglets removed, and, for certain airplanes, requires repetitive internal and external HFEC inspections of the lower outboard wing skin common to the external doubler repair at stringer L- 9.5 and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products.
Next: 2026-16506, Airworthiness Directives; Airbus Helicopters
The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Model EC 155 B and EC 155 B1 helicopters. This AD was prompted by a determination that new or more restrictive airworthiness limitations are necessary. This AD requires revising the airworthiness limitations section (ALS) of the existing maintenance manual (MM) or instructions for continued airworthiness (ICA) and the existing approved maintenance or inspection program, as applicable. The FAA is issuing this AD to address the unsafe condition on these products.