New FAA rule sets radio altimeter retrofit deadlines; FCC rebate program takes shape By Theresa Marr and Amber Harrison The FAA has released a signed final rule establishing new interference-tolerance requirements and compliance deadlines for aircraft radio altimeters. The rule, which FAA has sent to the Office of the Federal Register for publication, was coordinated with the Federal Communication Commission’s (FCC’s) Upper C-band order adopted Jul. 22. The FCC order establishes a rebate framework intended to help defray eligible radio altimeter retrofit costs. What the FAA rule does: Aircraft operated in the 48 contiguous states and the District of Columbia with radio altimeters installed must eventually use systems meeting FAA’s new minimum performance requirements for interference from C-band wireless signals. The requirements address radio altimeter operation at and below 500 ft. AGL and prohibit erroneous outputs caused by C-band interference above 500 ft. AGL. Aircraft without radio altimeters installed are not required to install them solely because of this rule. Compliance deadlines: • Dec. 30, 2030 — Aircraft operated under Part 121, and those operated under Part 129 with at least 30 passenger seats or a payload capacity exceeding 7,500 lb. • Oct. 31, 2034 — All other radio altimeter–equipped aircraft covered by Part 91, including aircraft operated under Parts 125, 133, 135, 136, 137, and 194, as well as remaining Part 129 aircraft. The FAA may authorize continued operation with a noncompliant system after the applicable deadline in extremely limited, unusual circumstances, subject to operational restrictions. Why it matters for VAI members: Most commercial helicopter and Part 135 operators fall under the October 2034 compliance deadline. That does not necessarily mean operators can continue all current operations without interruption until 2034, however. Beginning Dec. 31, 2030, the FAA expects to supersede the existing helicopter C-band airworthiness directive and impose nationwide restrictions on helicopters whose radio altimeters do not meet the new requirements. Those restrictions are expected to prohibit certain Category A and B takeoffs and landings, search-and-rescue and hover autopilot modes, and procedures requiring radio-altimeter minima. Operators may also need an FAA exemption to continue certain night-vision goggles (NVG) operations. These limitations could significantly affect air medical, public safety, offshore, utility, and other mission-critical operations well before the 2034 compliance deadline. The FCC rebate program is intended to help defray eligible retrofit costs , but it will work differently from a traditional reimbursement program. Rather than paying each claimant’s actual invoices, the program will use set rebate amounts for categories established by the FCC’s Wireless Telecommunications Bureau (WTB). Those categories may account for the number of radio altimeters involved, the general level of effort required for the retrofit, and the applicable compliance deadline. Rebates will apply only to radio altimeters already installed on eligible aircraft. Spare units and foreign-registered aircraft will not qualify. Who can claim: Eligibility depends on which FAA deadline applies. • For aircraft subject to the 2030 deadline, eligible claimants are operators holding a US air-carrier or operating certificate under Part 119 and operating eligible aircraft under Part 121. The aircraft must have at least one radio altimeter installed and an original certificate of airworthiness or original export certificate of airworthiness, issued before Apr. 1, 2030. • For aircraft subject to the 2034 deadline, eligible claimants are aircraft owners identified in the FAA Aircraft Registry. The aircraft must have at least one radio altimeter installed, be registered in the United States, and have an original certificate of airworthiness or original export certificate of airworthiness, issued before Jul. 1, 2031. Because the 2034 tranche is keyed to registered ownership rather than the operating certificate, operators flying leased or managed aircraft should begin determining who will be responsible for filing the claim. Where the money comes from: The rebates will be funded by winning bidders for Upper C-band licenses, not through federal appropriations. A third-party clearinghouse will administer the program, collect payments from licensees, and distribute approved rebates. This distinction matters because annual appropriations bills frequently remain unresolved as Congress approaches Sep. 30, the end of the federal fiscal year. Because the rebate obligation is tied to the wireless licenses rather than the congressional funding calendar, the program will not depend on annual appropriations. Licensees can also be required to replenish the fund if approved claims exceed the amount already collected. What remains undecided: The FCC’s WTB will develop the rebate categories, dollar amounts, documentation requirements, and claims procedures. The WTB must seek public comment on its draft proposals by Oct. 6, 2026, and finalize them as soon as feasible thereafter. That proceeding will present a key opportunity to shape how rebate categories and amounts account for rotorcraft-specific costs. Because payments will be based on categories rather than each claimant’s actual invoices, cost evidence submitted to the record will help determine what operators ultimately receive. Unless the WTB establishes earlier filing deadlines, rebate claims must be submitted no later than Jun. 30, 2031, for aircraft subject to the 2030 deadline and Apr. 30, 2035, for aircraft subject to the 2034 deadline. To qualify for a rebate, all necessary retrofit work on the aircraft must be completed by the applicable FAA compliance deadline. What members should do now: Begin documenting your aircraft, installed radio altimeters, ownership and lease arrangements, and anticipated retrofit needs. Ownership structure may determine who can file a claim, and operators with aircraft subject to different deadlines should note that the two tranches have different eligibility rules. VAI will gather cost information to support the record this fall, particularly installation costs by rotorcraft type and anticipated aircraft-out-of-service time. Members willing to share that data should contact the VAI Regulatory Affairs team at Advocacy@verticalavi.org. Detailed guidance will follow as the WTB develops the program. Theresa Marr is VAI’s senior director of legislative affairs. Amber Harrison is VAI’s director of regulatory affairs.
