Greenland’s airspace is now being protected by Danish F-35As a high-end signifier of allied presence that also illustrates how contemporary combat aviation is as much about supply chains, software, and permissions as it is about aircraft. A video clip that emerged recently showed two Danish F-35As accompanying a French tanker aircraft along the eastern coast of Greenland. The deployment itself can be easily seen as a proof of presence over a large island, but in fact, the scale of Greenland and its climate make it much more valuable to have sensors, tanking, and basing capabilities than presence. However, the video clip emerged at a moment when the benefits of the aircraft’s stealth, sensor fusion, and coalition capabilities are being weighed against worries about foreign maintenance and control.
This problem has been described in a clear manner in Denmark. Rasmus Jarlov, the chairman of the Danish Defense Committee, stated that “kill switch” in the literal sense is not relevant, saying on X: “The USA can certainly disable the planes by simple stopping the supply of spare parts.” This is because a reliance could become leverage in the future, which has been a concern for all nations who have the F-35.
The truth is more complicated than the rumor cycle, but more relevant to planners. The F-35 has a worldwide set of carefully orchestrated pipelines: parts, depot-level repairs for selected closed components, and a constant flow of data and software that keeps mission systems current. The F-35 community has also faced its share of schedule issues. A Government Accountability Office review, cited in the reporting, spoke of average delivery times of 238 days in 2024, largely because of the Technology Refresh 3 baseline that supports the Block 4 upgrade plan. In small inventory quantities, similar to those found in many European air forces, delivery times and upgrade opportunities can quickly translate into readiness gaps.
Dependence also appears in policies that are outside the aircraft itself. U.S. policies constrain the international operator’s freedom in exercising some test functions, and this has been a problem that keeps coming up in European debates on “sovereign” airpower. The more serious problem is not the far-off switch but the accumulation of friction points spares, special repairs, software updates, and access to mission data where a partner country’s freedom of action could diminish without a dramatic reason.
Mission data is the silent key to this whole discussion. The Mission Data File has been described as the F-35’s electronic ‘reference card’ that helps its fusion engine identify threats and targets and manage emissions. Without the Mission Data File, the aircraft could still operate, but it would have no purpose to begin with. Therefore, the “spare parts kill switch” is simply a useful shorthand for an even larger point: fifth-generation warfare is not an investment, but a relationship. The contradiction is further exacerbated by Greenland itself. U.S. defense strategists have long regarded the island as vital, particularly for early warning systems.
The radar at what was Thule Air Base now Pituffik Space Base since 2023 has been regarded by former U.S. defense officials as a vital component of homeland missile defense. The geography of Greenland also links North Atlantic air and sea routes, where the integration of allies is more important than any single platform choice.
This explains the importance of the Danish patrols, not merely in Denmark’s order book. They are a new reality of procurement that is emerging in Europe: it is no longer a question of whether an aircraft is capable, but whether its environment, its updates, its depots, its mission data, and its political permissions are things that can be relied upon over the entire life of the aircraft. In the skies above Greenland, the coalition logic of the F-35 is at play, and so too is the strategic price of having someone else maintain it at peak performance.
