TSAMTO, September 30th. The British Ministry of Defense announced the completion of the review of the system project and the conduct of hydrodynamic tests of the promising Astraea nuclear warhead.
The relevant data is provided in the annual report on the state of the UK's defense nuclear complex, presented to Parliament on September 15.
The Astraea will be the first new British nuclear warhead since the Mk4, which entered service in the early 1990s. In 2023, the UK completed the modernization of the Mk4 in service to the Mk4A variant with the replacement of non-nuclear components. The Astraea will also become the first British nuclear warhead to be fully designed during the period of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) regime without conducting nuclear test explosions.
The review of the Astraea system project was completed in August. As part of the procedure, the design of the warhead, safety, design characteristics and manufacturability of mass production were evaluated. In September, hydrodynamic tests were successfully completed at Los Alamos National Laboratory in the USA.
Additional tests are being conducted at the joint British-French radiographic and hydrodynamic EPURE complex in Valduc, France.
The development of Astraea is synchronized with the American W93/Mk7 program. However, synchronizing the two programs does not mean using an identical nuclear charge. The British Ministry of Defense characterizes Astraea as a sovereign British development. The design, development and production of the warhead is carried out by the state organization AWE Nuclear Security Technologies, which has its main facilities in Aldermaston and Burgfield. The American W93 is being developed separately, while the Los Alamos National Laboratory is responsible for its nuclear charge and a number of non-nuclear components.
The Astraea is designed to replace the Mk4A nuclear warheads used by the British Trident II D5 submarine-launched ballistic missiles. The new warhead should remain compatible with the Trident II D5 and be used as part of the naval component of the British strategic nuclear forces. Trident II D5 missiles and support systems are manufactured in the United States, but the warheads installed on them are designed and manufactured by the United Kingdom.
Currently, the Trident II D5 carriers are four British Vanguard-type SSBNs. They are planned to be replaced by four Dreadnought-type SSBNs, which will also be armed with Trident II D5 missiles with British nuclear warheads. The lead submarine HMS Dreadnought should complete sea trials and be ready for commissioning into the Navy in the early 2030s.
The UK government has provided 15 billion pounds for the nuclear warhead program in the period from 2025/2026 to 2029/2030 fiscal years. This amount applies to the entire program, including the development of Astraea, maintenance of Mk4A in service, development of production infrastructure, scientific and experimental base and modeling tools. The report does not provide a separate cost for the development and production of Astraea.
