High Quality Content by WIKIPEDIA articles! The BAE Systems Nimrod MRA4 was a maritime patrol and attack aircraft intended to replace the Hawker Siddeley Nimrod MR2. The rebuilt aircraft would have extended the operating life of the Nimrod fleet by several decades and have significantly improved the aircraft by almost doubling the flight range by installing more efficient Rolls-Royce BR700 turbofan jet engines. The conversion of the flight deck to a digital `glass cockpit` would have simplified control operations and reduced crew requirements. New detection systems were to be installed, as well as additional weapons for anti-submarine warfare.