Guardian (Tracked) Air Defence System Update:
Real WorldIn 1992 the Bloodhound Mk 2 missile system was retired from Royal Air Force (RAF) service and, with its demise, the UK lost its land-based medium/long-range surface-to-air missile capability. Although there was talk of a possible replacement for Bloodhound, the end of the Cold War and the perceived lack of any realistic threat meant that successive strategic defence reviews failed to include, or even consider the need for, a medium or long-range air defence system beyond that which was required for the Royal Navy (RN). As time passed, a ‘we have managed this long without’ mentality settled in and consecutive governments nibbled and slashed defence budgets with abandon such that, by 2024, a resurgent drone and missile heavy threat now sees the UK mainland effectively naked.
What-ifThe premise of this whiff is that in the 1980s, the UK Government implemented a policy that would see the UK’s land-based medium/long-range surface-to-air missile capability secured beyond the Bloodhound era. As I have already stated above, the UK did develop a medium-range air defence missile for the RN in the shape of Sea Dart and although the UK was keen to reduce military spending as part of a post-Cold War peace dividend, it would not have taken much for a land-based version of Sea Dart to have been developed. (Note: Just such a concept was indeed proposed RW using the Sea Dart Mod 2 missile and was to be called Guardian)
In my Alternative History timeline, I would initially see the static Bloodhound Mk 2 sites being replaced by static Guardian systems which would essentially be the ship-borne Sea Dart system (including its ‘below deck’ rotary magazines and associated radars) - much like this diagram.

My mobile Bloodhound Mk 4 would also be replaced with a Tracked version of Guardian mounting 4 ready-use missiles on a tracked Transporter, Erector and Launcher (TEL) based on the, then in service, M109 chassis. A similar hull variant would carry the Type 909 Target Illumination radar and engagement control system. Whilst a Bloodhound Mk 4 Flight consisted of 4 x 2-missile TELs and one ECV (each supported by a detachment FV432), the new Tracked Guardian Flight would have 4 x 4-missile TELs and 2 x ECV (each supported by a detachment FV103 Spartan {1}) split into 2 x Fire Teams. The increased number of ready-use missiles, additional ECV together with the increased capability of the Mod 2 missile {2} would provide a dramatic increase in firepower over the older Bloodhound system.
54 Squadron RAF Regiment, previously a Bloodhound (SP) unit, was equipped with the new tracked Guardian system in 1989 and, as part of the UK’s response to Iraq’s invasion of Kuwait in 1990, was deployed on Op GRANBY (Gulf War 1). During this time, 54 Squadron managed to shoot down 2 x Iraqi MiG 25R recon aircraft.
Although Tracked Guardian proved quite successful in its air defence role, the sustainability and flexibility of a heavy, fully tacked system sat less comfortably with the RAF and MoD as a whole. With the development of a lightweight, canistered version of the Mod 3 missile, a trailer mounted 6-round, trainable launcher was procured as Guardian 2 and had replaced all of the Tracked Guardians by 1998 and a significant number of the fixed Guardian sites by 2000. This final variant of the system would remain in service until 2012 when Sea Dart/Guardian was replaced by Sea Viper (Astor 15 and Astor 30) for the RN and Viper (Astor 30) for the RAF.
The model depicts TEL B1 of B Flight, 54 Squadron RAF Regiment as it appeared on the day it shot down the first MiG 25R with missile JB603. The vehicle is shown in both its transportation mode and its firing position. Of note is the fact that TEL B1 is loaded with standard white missiles as opposed to the green coloured missile the Squadron would normally operate within the European theatre. As the RAF’s fixed Guardian sites used the same magazine fed system as the RN, missiles were not routinely kept on the launch rails, and hence toning down the missiles was not an issue. Consequently, these sites used the same white coloured missiles as the RN. When 54 Squadron deployed to the Gulf, resplendent in their desert paint scheme, it was decided that the white missiles would better suite the tactical situation. The model was built from an AFV Club M109G, 3D printed Sea Dart missiles courtesy of Cults3D.com, a pile of plastic card and some homemade decals.










Notes:
{1} The FV 103 Spartan was already in service with RAF Regt and RAF EOD units.
{2} From Wiki: Mod 2 upgrade included ADIMP (Air Defence IMProvement) which saw the replacement of six old circuit cards in the guidance system with one, allowing the spare volume to be used for an autopilot. Used alongside a command datalink (sited on the Type 909 pedestal) it allows several missiles to be 'in the air' at once, re-targeted during flight etc. and allows an initial ballistic trajectory, doubling range to 80 nmi (92 mi; 150 km) with the upgraded 909(I) radar for terminal illumination only. The missile was a two-stage, 4.4-metre (14 ft) long missile weighing 550 kilograms (1,210 lb). It was launched using a drop-off Chow solid-fuel booster that accelerated it to the supersonic speed necessary for the operation of the cruise motor, a Rolls-Royce /Bristol Siddeley kerosene-fuelled Odin ramjet. This gave a cruise speed of over Mach 2.5, and unlike many rocket-powered designs, the cruise engine burned for the entire flight, giving excellent terminal manoeuvrability at extreme range.