Radio altimeter rule enters bizav's radar with pressure from NBAA on cost and deadline

The NBAA announced on March 11, 2026, its joining an industry coalition to challenge central aspects of the FAA's proposal that will require more interference-resistant radio altimeters on aircraft operating in the continental United States. Although the topic seems restricted to avionics, it is of direct interest to business aviation because it touches on four sensitive points for the operator: retrofit cost, aircraft unavailability during installation, regulatory risk and impact on the economic value of older models.

The radio altimeter measures the aircraft's real height in relation to the terrain and feeds important safety and operational systems, especially in critical phases such as approach and landing. The FAA's proposal arose in the context of the expansion of wireless services in the band called Upper C-band, neighboring the spectrum used by this equipment, and provides for new minimum performance standards to avoid interference.

Why does this weigh heavily on the operator's pocket

Under the proposal, regular aircraft and certain foreign operators would have to comply first, while the remaining universe, which includes operations under Part 91, where a large part of business aviation is located, would have an additional period of two years. Still, the discussion is far from trivial. The FAA itself estimates a total undiscounted cost of US$4.49 billion to retrofit the affected civilian fleet, while the regulatory text projects the need for tens of thousands of new or updated units.

In business aviation, the problem is not just the price of the part. Installing a new radio altimeter or retrofitting an existing system may require integration with older avionics architecture, supplemental engineering, additional certification, and scheduling in specialized shops already operating at limited capacity. Each day of aircraft downtime represents a loss of availability, an impact on flight scheduling and, for some operators, the need to resort to more expensive substitute solutions.

The pressure is higher on older planes

It was precisely this point that the coalition raised in the debate. In the joint response sent to the government, the group argues that retrofitting out-of-production aircraft tends to be slower, more expensive and less expensive.More complex because of reduced OEM support, incompatibilities with legacy systems, and the need to demonstrate compliance on an almost case-by-case basis. In market language, this means that the rule could unevenly affect the fleet and put more pressure on those who operate mature but still economically useful planes.

In this scenario, the issue stops being just technical and starts to touch on residual value. If the cost and complexity of retrofitting increases too much in certain models, some owners may have to choose between investing heavily to keep the plane ready to operate in the American market or limiting its use, if not accelerating a fleet exit. This type of decision directly impacts the asset's liquidity and ownership calculation.

Compliance is not an administrative detail

NBAA joined the discussion because, for bizav, regulatory compliance cannot be resolved with a simple internal bulletin. It is necessary to coordinate the maintenance schedule, engineering, certification, documentation, training and commercial availability of the aircraft. In small fleet operators, where a single plane concentrates a large part of the mission, the cost of a long or poorly planned stop can be proportionally harder than in large companies.

By joining the coalition, the association seeks to influence not only the merit of the rule, but also the way in which it will be implemented. The message is clear: security and protection against interference are consensual objectives, but deadlines, industrial capacity and the economic reality of the executive fleet will need to factor into the equation. For an industry that sells flexibility and availability, this is perhaps the most decisive point in the entire discussion.