Britain is spending $2.8 billion on upgrades to 40 of its 137 Typhoon jet fighters. The upgrades are being installed on the youngest Typhoons, which started entering service in 2013. The upgrade consists of an AESA solid state radar and a much-improved fire control system. This includes the capability to operate despite enemy jamming as well as detecting aerial and ground targets despite enemy electronic countermeasures. This type of equipment has been common in Typhoons used by other nations, including export customers. Some American fighters have been using this AESA gear for two decades and it is standard on new fighters like the F-22 and F-35. Britain is in the midst of receiving 74 or more F-35s and is developing, in cooperation with Japan, the even more advanced Tempest fighter. Japan is developing a different but similar FX aircraft which will use the same engine as the Tempest and may share some software.
The Typhoon upgrades will give Britain 40 Typhoon radars with fire control systems similar to those in the F-35 and Tempest. Britain wanted to install the upgrades on some of the 67 slightly older Typhoons but with the cost of the F-35s and developing Tempest, the money for that was not available. The upgrades for the latest 40 aircraft are extensive, cost $70 million per aircraft, and keep these Typhoons in service until retirement after 2040, possibly as late as 2060.
The oldest batch of Typhoons began entering service in 2003 and most of those 53 aircraft have already been retired. The remaining 20 will be gone by 2025. These early Typhoons lacked many of the upgrades included in the later batches.