OVERVIEW: The Nimrod R.1 is a strategic ELINT reconnaissance aircraft developed from the Hawker Siddeley Nimrod MR1 for the Royal Air Force. It was designed to detect, intercept, and analyze radar emissions and other electronic signals for intelligence operations.

DETAILS: Three Nimrod airframes were converted under Project R.1 between 1971–1974 and entered service with No. 51 Squadron in May 1974. Major external modifications included the removal of the MAD boom, installation of radomes on wing tanks and tailcone, and multiple internal ELINT antennas accessing the sealed weapons bay. Powered by four Rolls‑Royce Spey turbofans, the aircraft had a maximum speed of ~925 km/h, a long operational range of ~9,260 km. In the 1990s, the fleet received the “Starwindow” upgrade, adding wideband digital receivers, direction-finding, pulsed signal processors, and onboard analysis capabilities.

TYPE: Strategic ELINT Reconnaissance Aircraft

FUNCTION: The Nimrod R.1P was used to intercept and analyze radar emissions to build electronic orders of battle, monitor air defense systems, and support both Cold War and contingency operations. Its high-altitude loiter capability and electronic suite enabled long-endurance surveillance in international airspace without entering contested zones.

NOTE:
IOC: May 1974
Manufacturer: Hawker Siddeley (later British Aerospace)
Operators: Royal Air Force (51 Squadron)
Conflict used in: Cold War surveillance; Falklands War (1982); Gulf War; Operations in Afghanistan and Iraq; Libya (2011)

SOURCE:
Wikipedia – Hawker Siddeley Nimrod R1: https://en.wikipedia.org/wiki/Hawker_Siddeley_Nimrod_R1 ;
BBC News – Fact file: Nimrod R1: https://news.bbc.co.uk/1/hi/uk/2558557.stm ;
C-MANO DB – Nimrod R.1P specs & sensors: https://cmano-db.com/aircraft/2033/ ;
On‑Target Aviation – Nimrod conversion details: https://on-target-aviation.com/nimrod.html ;
Defense Web – Nimrod R1 retires from RAF service: https://www.defenceweb.co.za/aerospace/nimrod-r1-retires-from-raf-service/