Design Hawker Siddeley Nimrod

1 design

1.1 overview
1.2 avionics
1.3 armaments , equipment

design
overview

the nimrod first jet-powered maritime patrol aircraft (mpa) enter service, being powered rolls-royce spey turbofan engine. aircraft in role had been commonly propelled piston or turboprop powerplants instead maximise fuel economy , enable maximum patrol time on station; advantages of nimrod s turbofan engines included greater speed , altitude capabilities, more capable of evading detection methods submarines, whereas propeller-driven aircraft more detectable underwater standard acoustic sensors. inflight, nimrods had flight endurance of ten hours without aerial refuelling; mr2s later fitted receive mid-air refuelling in response demands in falklands war.

pair of nimrod r1s flying in formation, august 2004

at start of patrol mission 4 engines running, but, aircraft s weight reduced consumption of onboard fuel, 2 engines intentionally shut down, allowing remaining engines operated in more efficient manner. instead of relying on ram air restart inactive engine, compressor air crossfed live engine starter turbine; crossfeed duct later discovered potential fire hazard. similarly, 2 hydraulic systems on board designed powered 2 inner engines running. electrical generation designed far exceed consumption of existing equipment accommodate additional systems installed on nimrod s operational service.

the standard nimrod fleet carried out 3 basic operational roles during raf service: anti-submarine warfare duties typically involved surveillance on allocated area of north atlantic detect presence of soviet submarines in area , track movements. in event of war, reconnaissance information gathered during these patrols shared other allied aircraft enable coordinated strikes @ both submarines , surface targets. search , rescue (sar) missions important duty of raf s nimrod fleet, operating under air rescue coordination centre @ raf kinloss, , common sight in both military , civil maritime incidents. throughout nimrod s operational life, minimum of 1 aircraft being held in state of readiness respond sar demands @ times.

avionics

nimrod mr2 performing low pass @ alconbury, august 1990

the nimrod featured large crew of 25 personnel, although typical crew numbered 12 members, of operated various onboard sensor suites , specialist detection equipment. significant proportion of onboard sensor equipment housed outside pressure shell inside nimrod s distinctive pannier lower fuselage. sensor systems included radar, sonar, , magnetic anomaly detector; sniffer detect exhaust fumes diesel submarines well. nimrod , detection capabilities important component of britain s military defence during height of cold war.

the nimrod s navigational functions computerised, , managed central tactical compartment housed in forward cabin; various aircraft functions such weapons control , information sensors such large forward doppler radar displayed , controlled @ tactical station. flight systems , autopilot directly controlled navigator s stations in tactical compartment, giving navigator complete aircraft control. navigational systems comprised digital, analogue, , electro-mechanical elements; computers directly integrated of nimrod s guidance systems such air data computer, astrocompass, inertial guidance , doppler radar. navigation information manually input operators.

upon introduction service, nimrod hailed possessing advanced electronic equipment such onboard digital computers; increased capability of these electronic systems allowed raf s fleet of 46 nimrod aircraft provide equal coverage of larger fleet of retiring avro shackletons. design philosophy of these computerised systems of man-machine partnership ; while onboard computers performed of data sift , analysis processes, decisions , actions on basis of data remained in operator s hands. support nimrod s anticipated long lifespan, onboard computers designed capable of integrating various new components, systems, , sensors added in future upgrades. after mission, gathered information extracted review purposes , further analysis.

armaments , equipment

the nimrod featured sizeable bomb bay in which, in addition armaments such torpedoes , missiles, housed wide variety of specialist equipment many purposes, such 150 sonobuoys asw purposes or multiple air-deployed dinghies , droppable survival packs such lindholme gear sar missions; additional fuel tanks , cargo carried in bomb bay during ferrying flights. other armaments equippable in bomb bay include mines, bombs, , nuclear depth charges; later munitions included sting ray torpedo , harpoon missile increased capabilities.

the open bomb bay of nimrod

the nimrod fitted 2 detachable pylons mounted underneath wings used missiles such martel; 2 specialised pylons later added enable equipping of sidewinder missiles, used self-defence purposes hostile aircraft. powerful remote-controlled searchlight installed underneath starboard wing sar operations. reconnaissance missions, aircraft equipped pair of downward-facing cameras suited low , high-altitude photography. in later years newer electro-optical camera system installed greater imaging quality.

various new ecms , electronic support systems retrofitted onto nimrod fleet in response new challenges , increase type s defensive capabilities; additional equipment provided more effective means of identification , communication. number of modifications introduced during 1991 gulf war; small number of mr2s fitted improved link 11 datalinks, new defensive ecm equipment including first operational use of towed radar decoy, , forward looking infrared turret under starboard wing.