FAA proposes new standards requiring radio altimeter upgrades, replacement VAI is focusing on operational continuity and costs for the proposed rule in its work with the FAA and US government agencies, as well as industry standards bodies and coalitions. The rule would amend Part 91 and add new provisions under Parts 121 and 129, effectively making US airspace operations conditional on the use of compliant radio altimeter systems. The FAA has proposed a new rule, Requirements for Interference-Tolerant Radio Altimeter Systems, that would set new minimum performance requirements for radio altimeter systems. The proposal responds to a planned auction and expansion of wireless services into the Upper C-band, which is adjacent to the frequencies used by radio altimeters. The rule would amend Part 91 and add new provisions under Parts 121 and 129, effectively making US airspace operations conditional on the use of compliant radio altimeter systems. FAA’s rule is driven by the One Big Beautiful Bill Act signed in July 2025, which directs the FCC to complete a competitive bidding auction for certain spectrum bands. The subsequent authorization and deployment of new services in this spectrum has the potential to interfere with existing avionics. The spectrum auction is scheduled to occur in 2027. For US vertical lift operators, the primary concern is the cost and timing of equipage. The NPRM would require radio altimeters to withstand stronger adjacent-band interference while continuing to provide accurate altitude data to pilots and aircraft system. The FAA proposes two compliance milestones. The first would align with the FCC authorization date for new Upper C-band wireless services and would apply to Part 121 aircraft and larger Part 129 operations. The second would apply two years later to all other aircraft equipped with radio altimeters, including vertical lift aircraft. The FAA anticipates the initial compliance date will fall between 2029 and 2032, with the final compliance date two years after that. This rule is anticipated to result in the replacement or significant upgrade of a large portion of the US radio altimeter fleet. For many vertical lift aircraft, compliance is expected to involve more than a straightforward equipment replacement. Integration, certification, antenna and wiring changes, and downtime are likely to drive total cost. Some estimates indicate that operators could face costs in the range of $100,000 to $500,000 per aircraft. VAI is actively engaged with FAA, FCC, industry standards bodies, and industry coalitions, including participation in the relevant working group promoting reasonable performance standards for next-generation radio altimeters while mitigating adverse impacts on affected operators. VAI is also advocating for a retrofit stipend tied to the spectrum sale. The goal is not to oppose the auction itself, but rather to shift retrofit costs to spectrum purchasers through auction proceeds, eliminating the replacement cost burden for individual aircraft owners and operators while protecting safety and mission capability. VAI will work with regulators as well as submit formal coalition comments highlighting member data on retrofit pricing, aircraft downtime, certification pathways, supply chain capacity, and mission impacts across all vertical lift operations.
