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Message: <blockquote data-quote="newboy1" data-source="post: 203535" data-attributes="member: 1614">The FE 541 INAS was fitted to Harrier GR1 and GR3. The USMC AV8A was fitted with the same system as the GR1 so that HSA publication you mention probably has all you need to know about the weapons modes and HUD symbology from a Pilot's perspective (although in 1971 the whole mode suite may not have been fully developed). It did have an Unplanned Attack mode which was probably the closest to a CCIP solution. I seem to remember it generated a fixed "target bar" on the bomb fall line which represented a crosswind-compensated release solution for the weapon chosen/attack altitude etc. There certainly wasn't a "release cue" as used for Planned Attacks. Your description of the Target Bar and Release Cue interaction is correct for a Planned Attack except that the Release Cue was driven by "time to go" - when it hit the Target Bar, time to go was 0, and the weapons were released. The system could be set to release a stick of bombs, and in that case the Release Cue would appear to bouce repeatedly off the Target Bar.The Harrier and Jaguar HUD symbology was almost identical because they both used the same units by Smiths.  The earliest versions of INAS were purely analogue, but some of the GR3 LRUs were upgraded in the late 1970s to add digital circuitry to the Weapon Aiming side.<blockquote data-quote="Adam106">I’m particularly interested in the navigation and attack capabilities of the early Harriers, in particular Falklands era.  Now for the Harrier GR3:The GR3 used the Ferranti FE 541 inertial attack system – an early (analog?) INS system, which was ahead of its time in 1969 but often said to be too complicated for the aircraft it was put into…. I know CCIP / Planned attack etc is irrelevant for the Falklands since it wasn’t available due to problems aligning the FE 541 on board ship. However the GR3 had a sophisticated system for both planned and target of opportunity attacks. Some of the HUD symbology can be seen here:<a href="http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200108.html">http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200108.html</a>Clearly the GR3 was capable of computer assisted planned attacks on known locations, but again, was there a CCIP mode? I ask because there seems to be no ‘release cue’ present on the bomb fall line. This was a short little line that would rise up to meet the ‘target bar’ (the one aligned over the target), when the two lines met the bombs would release automatically. The little ‘release cue’ represented I think a CCIP solution – at least it does on the Jaguar for which I have a NAV / ATTACK Brochure produced by British Aerospace. Now the HUD symbology for both the Harrier and Jaguar look very similar (both made by Smiths), so without the ‘release cue’ I ask the question did the Gr3 have CCIP for bombs? Again there seems to be no specific mention of it in my research.Does anyone own or has seen this manual:<a href="http://www.flight-manuals-on-cd.com/AV8.html">http://www.flight-manuals-on-cd.com/AV8.html</a> - CD 2 ‘Manufacturers Pilot's Notes for the Harrier GR.Mk.1, HSA Publication No 25 dated 2-12-71 with approx 196 pages.’ Does it contain any further information on the navigation / weapons system?Adam.</blockquote></blockquote>

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