The US is building new underground launch facilities for Sentinel nuclear missiles

The US Air Force is beginning construction of new underground launch complexes designed for the next-generation Sentinel intercontinental ballistic missiles (ICBMs). Cold War-era silos have become obsolete and are incompatible with modern technology. The solution is modular underground complexes that enable faster construction and easier maintenance.

The US Air Force has begun planning the construction of new underground missile silos needed to house the next-generation Sentinel-class intercontinental ballistic missiles (ICBMs). The project raises the question of why it is not simply possible to use existing facilities dating back decades.

Old silos do not meet requirements

The launch silos currently in use largely date from the Cold War era, when an extensive nuclear deterrence infrastructure was built out. Over the decades, both the construction of the silos and the supporting technology have become so obsolete that modernizing them for contemporary weapons systems has become complicated and costly. The Sentinel missile is larger and technologically more complex than its predecessors, so the physical dimensions and infrastructure requirements do not match the earlier facilities.

Additionally, modernizing the outdated silos' maintenance and security systems is in most cases more expensive than building new facilities from scratch. According to military experts, reconstructing the old silos would present both technical and logistical challenges that could jeopardize the entire programme schedule.

Modular approach

The new approach is based on a modular construction philosophy that resembles modern industrial construction more than traditional military facility development. The underground complexes are assembled from pre-fabricated modules, which allows construction work to be accelerated and reduces on-site labour.

This method also offers long-term flexibility: in the future, it will be easier to make upgrades or replace components without having to rebuild the entire facility. This is an important factor given that Sentinel is intended to serve for decades.

The next era of nuclear deterrence

The Sentinel programme is part of the US's broader nuclear arsenal modernization plan, aimed at maintaining reliable strategic deterrence for decades to come. The construction of new launch complexes demonstrates that modernization is not limited to the missiles themselves, but encompasses the entire supporting infrastructure.

The project represents a significant investment in the land-based component of the US nuclear triad and sets a standard for how future approaches to strategic weapons infrastructure development may be conducted.