An unreliable nav system that pilots refused to rely on. Zero precision attack capability. Very limited night attack capability. Execrable airborne LRU reliability levels. Degradation of auto weapon delivery. That was the Indian Air Force fleet of MiG-27s towards the end of the 1990s -- one of the world's best strike aircraft in the 1970s, but utterly obsolete two decades later. A proposal was put up to organise a comprehensive upgrade of the fleet to transform the aircraft into a potent, accurate, all weather, day or night interdictor. Fortunately, foreseeing the government stalling the proposal, the IAF began discussing the possibility of a fully Indian upgrade programme involving HAL and the Defence Avionics Research Establishment (DARE). As you can imagine, the Russians weren't pleased, but they'd already given the Indian government reason to keep them out of main part of the programme.
Finally, on 14 March 2002, a momentous tripartite agreement was signed between the Indian Air Force, HAL and DARE. The prime agency for the upgrade was DARE, with HAL as the joint agency. Regional Centres for Military Airworthiness (RCMAs) and CEMILAC were also involved.
The team knew it needed to work fast -- this was a litmus test of what a fully Indian upgrade programme could achieve in a short time. For starters, to reduce development time, the team resorted to concurrent engineering and began using proven hardware and software modules common to the Su-30MKI and Jaguar NAVWASS programme. To save flight test and evaluation time, two prototype upgraded aircraft were made, according to a detailed presentation on the upgrade by project director P.M. Soundar Rajan of DARE. The development methodology was rigorous but efficient, with multiple agencies breaking a lot of institutional barriers to work together like they never had before.
The MiG-27 needed plenty of work. Equipment that went into the upgrade included a HUD and a full colour high definition display (HDD). The core of the upgrade involved two new pieces of computer equipment in the Flogger's nose bay. A new laser ranger replaced the old KLEN system. The main nav sensor, the INGPS along with VOR/ILS were also located in the nose bay. The new electronic warfare suite included a new radar warning receiver, an ELTA podded jammer and counter-measures dispenser system (CMDS). The upgraded aircraft was also made capable of carrying a laser designation pod and a photo recee pod.
Cutting down time taken to plan a mission was a high priority under the upgrade terms. The IAF's Software Development Institute (SDI) was roped in to develop a brand new mission planning system (MPS), which brought down mission planning time from 2-3 hours to about 30 minutes. A data-transfer unit was also conceived, to transfer RWR pre-flight messages (PFM) and MPS data straight to the aircraft -- a common function on modern fighters, but a breath of truly fresh air for the lumbering MiG-27. The system does, however, have a shortcoming - PFMs for the ELTA self-protection jammer and INCOM R/T crystallisation cannot be loaded through the DTU and still have to be fed directly into the aircraft.
The upgraded cockpit was a true legacy leap. Livefist reported earlier on the dramatic comparison of the MiG-27 cockpit, before and after upgrade. The upgraded cockpit is, as DARE puts it, "neater, de-cluttered and much more functionally ergonomic as compared to the non-upgrade cockpit". No argument with that. The RWR and CMDS were placed in the pilot's primary field of vision. An indigenous MFD displayed maps, horizontal situation and laser pod video. With time required to feed in date pre-mission reduced by a factor of four, and less time for alignment, the time for launch was brought down dramatically.
What, in effect, the MiG-27 upgrade has made possible is substantially reduced the pilot's workload. He no longer has to pay as much attention to navigation as he used to, situational awareness is no longer a daunting challenge even while flying at low levels and routine tasks have been shifted off the pilot's plate, allowing him to focus less on flying and more on tactics and the mission at hand. Target acquisition is also remarkably more efficient and intuitive now. Targets can now be acquired even in the dark night laser designator pod video, and since this involves head-down work, HUD symbology is overlaid over the video. Little things like this have transformed the MiG-27 mission experience. Pilots can now also leave the flying to the auto-pilot, now fully integrated in the auto-nav and auto-attack modes. The centre of the display has been designed to be un-cluttered to allow pilots to easily locate and identify the target. The sensor is slewable too. Overall, a substantially improved nav-attack system. For example, in a CCIP dive, a manoeuver that required every last shred of the pilot's attention, now has very accurate sights catering for the aircraft's changing parameters and allowing the pilot to monitor terminal air defence activity, managing the ECM suite and managing overall situational awareness.
The upgrade has given the MiG-27 new modes of attack, including CCRP, CCIP memory and Target of Opportunity -- these have given pilots the flexibility to attack planned and unplanned targets with equal efficacy. On the upgraded MiG-27, virtually attack parameters can be adjusted with a flick of a control switch now, and will no longer involve untimely sweats in the cockpit.
Weapon accuracy was a real concern. During upgrade trials, an upgraded MiG-27 conducted an HALR laser-pod assisted drop of a 500-kg dumb bomb from 7.5-km. Its missed distance was 15-metres. This was a dumb bomb, not a PGM.
The MiG-27s electronic warfare suite underwent many substantial changes. For starters, the front antennae of the Tarang 1B radar warning receiver (RWR) were moved from the wing leading edges to the nose, removing the earlier problem of masking which has apparently plagued the Tarang experience in virtually every other aircraft it has been used on. Incidentally, the upgraded MiG-27 is now the only aircraft in the Indian inventory that provides true 360-degrees, mask-free RWR cover. The self-protection jammer and and countermeasures dispensing system (CMDS) can now be autocued by the RWR, and the new integrated display provides, for the first time on the MiG-27, a perfectly clear picture of the electronic orbat around the aircraft.
The MiG-27 continues, however, to be a highly controversial aircraft in Indian service, recently seeing a long spell of grounding. Former IAF flight safety chief Air Marshal PS Ahluwalia has long argued that the MiG-27 engine has fundamental flaws that make it a dangerous machine to fly, and should be phased out forthwith. More on this last bit soon.