RAF Typhoon fighter jets will get a fresh £40 million investment in technology to improve their defences, Sir Michael Fallon has announced.
The Defence Secretary said the "cutting-edge" improvements would help the Armed Forces deal with "ever-evolving" threats.
The contract has been awarded to UK-based company Leonardo and will upgrade the aircraft's Defensive Aids Sub System (DASS), which protects it from both enemy planes and missiles launched from the ground.
It will enable the Typhoons to continue carrying out missions such as protecting Britain's airspace as part of the quick reaction alert team and carrying out air strikes on Islamic State (IS) in Iraq and Syria.
The contract will run over two years and sustain 65 high-value jobs at Leonardo's site in Luton as well as 41 jobs at BAE Systems in Warton, Lancashire.
It comes as RAF pilots test advanced weapons and software upgrades for the Typhoon.
Sir Michael said: "Our Armed Forces face ever-evolving threats so we must invest in cutting-edge technology to ensure they can operate in hostile theatres. Our growing defence budget and £178 billion equipment plan makes this possible; giving UK forces the defences they need to protect them, their kit and the people of Britain.
"The RAF's Typhoon jet is already a state-of-the-art combat aircraft that protects the UK both at home and abroad, but today's announcement is a clear example of how it is being continually enhanced and upgraded so it remains as effective tomorrow as it is today."
DASS provides a set of self-defence sensors and countermeasures which detect and evaluate potential threats and automatically deploy the most effective countermeasure.
It includes electronic support measures, missile warning, on-board electronic countermeasures and towed radar decoys.
The Typhoon force is currently operationally based at RAF Coningsby in Lincolnshire, RAF Lossiemouth in Scotland and the Falkland Islands.