Desert Storm Part 1 (original) (raw)
The Gulf War has demonstrated yet again the central importance of electronic warfare to the conduct of a modern air war. So overwhelming was the weight of the initial attack, that the Iraqi IADS (integrated air defence system) collapsed in hours, never to regain anything approaching a semblance of functionality.
What transpired was no surprise to informed observers, as the Libyan raid of 1986 and Israeli strike on the Bekaa Valley in 1982 both produced similar effects, albeit on a much smaller scale. It was clear that a repeat performance was a certainty if hostilities did break out, the only uncertainty lay in its form and timing.
The extensive television coverage of the air war from the outset provided a clear indication of what was happening, and the queues of HARM loaded F-4G Weasels and F/A-18s congesting Saudi taxiways left no doubt whatsoever as to the ferocity of the battle taking place hundreds of miles away. It was quite clear to informed observers that Iraq's IADS was on the receiving end of an unprecedented assault, very different from the piecemeal Weasel and Iron Hand operations of the Vietnam period.
The destruction of Iraq's IADS is a very good study of contemporary Western doctrine in the area of electronic combat, and deserves thus a close examination.
The Target - The Iraqi IADS
Australian Aviation published two brief reviews of Iraq's electronic order of battle, in November 1990 and April 1991. The Iraqi IADS was a composite system which integrated European and Soviet search and acquisition radars, and a range of Soviet and European SAM and AAA systems, all tied together with a French built Kari C3 (Command/Control/Communications) network. While smaller than the now defunct Soviet system in central Europe (Western TVD), the system had a respectable capability and comparable if not higher density of SAM and AAA systems, with considerable redundancy in communications links and hardened C3 facilities.
Organisationally the IADS was split into three principal elements, a national fixed site strategic system using fighters and SA-2 and SA-3 systems covering key airfields and strategic air defence sites, operated by the Iraqi air force. This system was supplemented by Republican Guard operated SAM and AAA systems covering key nuclear, biological and chemical warfare facilities. Finally, the Iraqi army had its own mobile radar, SAM and AAA systems tasked with protecting both fixed sites and units in the field.
Geographically the national IADS was split into several large zones, in each of which were located central local C3 facilities, one or more large hardened airbases and a network of communications links to fixed radar and SAM sites. Control of the whole network was centred in hardened facilities in the vicinity of Baghdad. While microwave links were used extensively, these were backed up by landlines.
The structure of the system reflected the Soviet Air Defence Force (PVO) and Army Air Defence (PVO-SV) models respectively. The strategic air defences employed large GCI/EW (Ground Controlled Intercept/Early Warning) radars such as the Soviet P-35M and P-37 Bar Lock, which were used for wide area surveillance and early warning, these large MTI (Moving Target Indicator - ie low PRF) E/F (2.6-3 GHz) band systems being situated at key geographical locations to cover principal air bases and population centres.
Bar Lock systems employ a pair of trailer mounted truncated paraboloid reflectors, and have a range of the order of 120 NM, the whole antenna/trailer assembly rotating at 12 rpm for 360 degree scan with six stacked beams for approximate height finding. Where low level coverage is required, they are typically supplemented by a Side Net E-band nodding height finding radar.
The air force operated GCI/EW system formed the top tier of the IADS, supporting fighters with GCI vectors, but also datalinking early warning information down to individual SAM and AAA batteries.
These were in turn directly supported by a range of early warning and acquisition radars, mobile and relocatable, such as the Flat Face, Squat Eye and Spoon Rest. These acquisition radars played a key role in the IADS, as they provided precise tracking information to SAM systems. They would also, under proper operating conditions, remain off the air until a target was to be engaged, at which time they would light up, acquire and track the target and feed the target's parameters to the fire control radars associated with the SAM and AAA systems in use.
The P-15 Flat Face is a low PRF MTI radar which uses a pair of elliptical paraboloid antennas on a short mast above a trailer, operating in the B/C (UHF) band the radar is generally credited with respectable look down performance into clutter and good ECCM performance. As several late model units were captured by the Allies during the eighties, the Flat Face was wholly compromised. Reports of testing by the French suggested the radar had remarkably good performance for its class of system, and good ECCM.
The P-15 Flat Face was originally used by the Soviets to support the SA-3 Goa, but since they were reluctant to export their mobile Long Track acquisition radars to non-Warpac nations, the P-15 was largely substituted. The Flat Face was the principal Soviet mobile battlefield surveillance/acquisition radar in use in Iraq and is associated with grouped area defence batteries of SA-3, SA-6 and point defence batteries of SA-8, Roland, ZSU-23-4P, SA-9 and SA-13. Where low altitude coverage was required, the P-15M Squat Eye was used. The Squat Eye is a direct derivative of the P-15, using essentially the same hardware but with only a single antenna mounted at the top of a 100 ft mast.
A typical arrangement was to colocate a Flat Face and Squat Eye at a single site, both vans buried in revetments and covered with nets. The radar site would then provide high altitude coverage to the maximum range of the systems, and low level coverage limited by the height of the P-15M mast. Most acquisition radars were situated close to the targets covered by the area defence and point defence SAM systems which they were designated to support, and were often supplemented by height finding radars such as the Thin Skin, a truck or trailer mounted H-band nodding elliptical paraboloid system.
The older SA-2 systems were supported by the geriatric VHF/A band P-12 and P-12M Spoon Rest low PRF MTI acquisition radars. These systems use an array of twelve Yagi antennas in two banks, mounted on horizontal booms on a common mast. Early models were mounted on a van trailer, newer build equipment on ZiL-151, 157 or Ural 375 trucks. While the P-12 is considered an unsophisticated analogue system by Western standards, it has a respectable range of 150 NM at altitude and its large wavelength improves its detection range performance against low RCS targets such as the F-117A. The Spoon Rest was wholly compromised when an Israeli commando team captured and removed a whole system in 1969.
Iraqi Area Defence SAM Systems
The third tier in the IADS hierarchy were the fire control/tracking radars associated with the SAM and AAA systems in use. These were typically co-located with the SAM or AAA batteries they supported and in most instances were dedicated to the weapon in use. The SAM systems were mainly of Soviet origin, with some European weapons in use. Area defence coverage was provided by approximately 70 batteries, close to evenly split in numbers between the SA-2, SA-3 and SA-6.
The most numerous weapon was the SA-2 Guideline, supported by the Fan Song fire control radar. Almost no information is available on the composition of the SA-2 force, but the period over which the weapons were acquired suggest that most were of the older SA-2B variant supported by the almost devoid of ECCM Fan Song B radars, with later supplementary purchases being of the later build SA-2F model with the Fan Song E or F radar, the latter types incorporating ECCM measures to counter jamming.
All Fan Song radars use separate beams for horizontal and vertical angle tracking of the target, with separate antennas for each. The fan shaped beams are scanned mechanically 15-17 times a second, the horizontal beam being pulsed to provide ranging information. Targets are acquired at low PRF, which is doubled once tracking is initiated. The missile is then launched and commanded to a collision with the target with commands from a UHF band very low PRF uplink. Up to six targets can be tracked concurrently, and three missiles guided concurrently against a single target.
A typical regimental structure is that of a headquarters equipped with a Spoon Rest or Flat Face early warning/acquisition radar, supported by a Side Net or Thin Skin heightfinder, these systems providing early warning and target handoff to three launcher battalions. Each launcher battalion has a Spoon Rest acquisition radar and a Fan Song fire control radar, to support six revetted single rail launchers. Missiles are moved on a single round transloader semi-trailer, towed by a ZiL-157V or ZiL-131V 6 x 6 tractor.
The Fan Song was jammed so successfully by the Americans in Vietnam that ECCM measures were added as a priority. The Fan Song E uses a LORO (Lobe On Receive Only) technique, with auxiliary transmit antennas, whereas the Fan Song F uses auxiliary optical angle tracking. Both techniques cannot prevent uplink jamming of the UHF command channel. The SA-2 weapon system was wholly compromised due capture of units in the Middle East and via US access to Egyptian systems.
The limitations of the SA-2 caused the Russians much embarrassment in Vietnam resulting in the deployment of the smaller and more agile SA-3 Goa, designed to engage low flying targets. Reports on how many Goa systems were used by Iraq vary, but the numbers indicate about 25 battalions.
The Goa is guided via command link from the I band Low Blow fire control radar, designed with LORO ECCM from the outset. The Low Blow uses a centrally mounted single truncated paraboloid transmit antenna with a single boom feed, and separate 45 degree angled mechanically scanned receive trough antennas, mounted in a characteristic chevron pattern. The angling of the antennas supposedly reduces the amount of ground clutter seen by the receiver. A backup optical tracker is used to defeat angle trackbreaking jam techniques, and MTI techniques are used to defeat chaff. The missile is steered by commands from a D band uplink antenna mounted on top of the fire control system, the missile's position is tracked via a beacon on the missile. Up to two missiles can be guided against one target concurrently, and six targets tracked concurrently.
A typical battalion uses a single Flat Face or Squat Eye acquisition radar which supports a single Low Blow fire control radar, and typically four static launchers. These may be two rail or four rail systems, the latter adopted with the deployment of the SA-3B missile. Missiles are transported in pairs on a ZiL-157 or ZiL-131 6 x 6 transloader truck. Four battalions make up a regiment, which is equipped with an acquisition radar system, typically a Spoon Rest with a Side Net, or a Squat Eye operating with a Flat Face and Thin Skin.
While the Goa missile is more agile than the Guideline, and its radar has better ECCM and low altitude tracking performance, the type's performance in SEA and the Middle East was hardly better than its predecessor's and since the US had access to systems captured by Israel in 1973, its weaknesses were well understood.
The most potent area defence SAM system was the Iraqi army's mobile SA-6/Gainful 9M9 ZRK Kub/Kvadrat, which is supported by the Straight Flush radar system. The ramjet sustained 9M9 missile can pull 15G and is equipped with semi-active radar terminal homing supported by a proximity fuse, all of which vastly improved kill probability in comparison with the SA-2 and SA-3.
The Straight Flush mobile fire control radar system is a fully self contained acquisition and guidance package mounted on a tracked 2P25 chassis. A stack of two independently rotating coaxial turrets supports separate acquisition and guidance radars. The lower half of the stack mounts a large horizontal G-H band parabolic section antenna, with four separate feeds producing four stacked beams for approximate heightfinding, three are H band, one is G band. While details have not been published, it is reasonable to assume this system is a low PRF MTI radar, its purpose is to acquire and track multiple targets and provide track parameters to the fire control system.
The upper turret mounts the cassegrainian I band tracking and illuminating antenna. Once a target is selected for attack, using parameters from the acquisition system, the tracking antenna is slewed onto the target and initiates precise target angle tracking and ranging. Angle tracking is achieved by conical scanning, the radar operating in pulse mode during the command link guided midcourse phase of the missile's flight to provide ranging information, which is not required during terminal homing, when the radar switches to continuous wave operation to illuminate the target. The missile then homes in to impact. While there is little consensus in the open literature, it is reasonable to assume that early rounds had conically scanning seekers, with later build seekers fitted with monopulse seekers for improved ECCM. A typical engagement will involve a three round salvo on one target.
A typical Iraqi Gainful regiment structure has a Flat Face, Squat Eye and Thin Skin providing target acquisition for five batteries, each with a Straight Flush and four three round tracked 2P25 TELs. Reloads are carried on a hoist equipped Ural-375 6 x 6 transloader truck, which carries three rounds.
The Gainful debuted in the 1973 war, accounting for most Israeli losses due SAMs, mainly due inappropriate warning receiver fit on the IDF's fighter aircraft. The Bekaa Valley battle of 1982 saw the Israelis even the score, using ARMs to cripple the Straight Flush systems and then killing off the TELs with Mk.82. Samples of late build SA-6 were captured in Chad in 1987, and subsequently tested on a missile range in the UK, where the missile demonstrated high accuracy.
Iraqi Point Defence SAM Systems
The area defence SAMs were supplemented by approximately 250 point defence SAM systems, which if PVO doctrine were to be followed, would have made between 65 to 140 mobile batteries of various compositions.
The most potent point defence SAMs were the SA-8 Gecko and the Franco-German Euromissile Roland. Both systems use a mobile fully self contained TELAR as the fire unit, and both have autonomous acquisition radars. In concept both are comparable to a mobile version of the Rapier used in this country.
The 9M33 ZRK-Romb or SA-8 Gecko is derived from the naval Osa-M SA-N-4 Gecko, deployed in the early seventies on smaller combatants. The SA-8 uses an amphibious BAZ-5937 TELAR vehicle, which carries a turret with trainable launch rails and the Land Roll radar equipment. The H band target acquisition radar uses a folding paraboloid section antenna with 360 degree scan, this system uses multiple stacked beams for height finding. It is reasonable to assume it is a low PRF MTI system similar to that in Roland, as this technique is less demanding of signal processing than pulse Doppler, yet provides adequate clutter rejection for low altitude operations.
Once a target is acquired the turret is trained upon it and the large J band pulse mode tracking system engaged, this system uses a side truncated cassegrainian dish with a characteristic flat dielectric blast shield. The tracking radar uses frequency hopping and monopulse angle tracking techniques to defeat jamming, as such it has the best ECCM capability of any Soviet export system. The tracking antenna is flanked on either side by a guidance antenna package, which generates I band capture beams after launch, an I band tracking beam to follow the missile's flightpath, and I band uplink signals to command the missile. The weapon uses fully automatic command to line of sight (CLOS) and the fire control system will collide the missile with the target. Backup optical tracking is fitted, two rounds can be fired at one target concurrently.
Older SA-8A Geckos carried four ready rounds on open rails, later SA-8B six in box launchers. A typical deployment involves a battery with four TELARs, two BAZ-5937 transloaders and a BTR-60PU-12 8 x 8 command vehicle.
The Roland is the Western equivalent to the SA-8, also deployed in the seventies and employed by Germany, France and the US Army. Like the SA-8 it uses a TELAR platform, the Iraqis purchasing the French AMX-30 chassis. The fully traversable turret has rails with two ready rounds, and can reload a further eight from magazines in the hull on either side of the turret. The rear of the turret mounts a cos**2 antenna for the D band Thomson CSF MTI acquisition radar, which will use multiple or split feeds for heightfinding via stacked beams. The antenna type is used to reduce the size of the ground return, ie the clutter which would obscure a target.
The front of the turret mounts the Siemens J band low PRF tracking radar, which uses an elliptical cassegrain antenna under a blast shield. The radar uses monopulse angle tracking to defeat countermeasures, and has two channels, one for the target and one for the missile's CW beacon. Next to the tracking radar are situated an optical sight and a command link antenna. Like the SA-8 the Roland uses fully automatic command to line of sight guidance.
Both the Roland and the Gecko are considered serious threats to low flying aircraft as they can be easily hidden and operate autonomously, while their tracking radars are substantially immune to simpler trackbreaking ECM techniques by virtue of monopulse angle tracking. As was to be later proven, the Roland lived up to its reputation.
The Roland and Gecko were the best but not the most common point defence SAMs used. The most common system was the 9M31 Strela 1 or SA-9 Gaskin. This weapon is comparable to early models of the Sidewinder based Chapparel, and uses a BDRM-2 amphibious scout vehicle chassis as a TEL, with four boxed ready rounds. The missile itself is an unimpressive lightweight heatseeker with an uncooled Lead Sulphide detector element, capable of tail aspect engagements only.
The Gaskin is usually operated in conjunction with the formidable ZSU-23-4P Shilka SPAAG system, which uses a similar chassis to the Gainful TEL. The ZSU-23-4P employs a J band Gun Dish pulse mode (magnetron) acquisition and tracking radar and is a fully self contained mobile system, whereas the SA-9 must be cued to a target for seeker lock-on and launch. Gaskin batteries often use a single Gun Dish radar mounted on a ZiL-157 6 x 6 truck, to provide warning of inbound aircraft. Soviet and some Warpac Gaskins also carry the Hat Box ESM equipment, which cues the operator to the radar and altimeter emissions of low flying aircraft, but it is not known whether the Iraqis had this equipment or whether they were competent to understand its use. As the Gaskin has been captured on many occasions by Western aligned forces, it has been wholly compromised.
The Iraqis had also acquired, more recently, the new 9M37 Strela 10 or SA-13 Gopher heatseeking SAM. Using a tracked MTLBu TELAR, the SA-13 system has a rangefinding radar fitted and uses a bigger missile than the SA-9. Reports on the missile's seeker are conflicting, but it does appear that a cooled detector with reasonably sophisticated optical filtering is used, conferring all aspect capability.
In Soviet deployments the SA-13 is formed into batteries with the new 2S6 SPAAG, four of each commanded from an MTLBu command vehicle and all relying on a separate Dog Ear acquisition radar, mounted on a dedicated MTLBu chassis. It is not clear whether the Iraqis were sold the Dog Ear, but it is likely they deployed the Gopher in a similar fashion to its predecessor the Gaskin.
Deployment
A typical composition for the Soviet PVO model would see static area defences implemented with batteries of SA-2 and SA-3, with mobile area defences and gaps in static defensive coverage plugged with the PVO-SV SA-6. The area defences would be supported by early warning radars at key sites, these covered redundantly by the early warning and acquisition radars of the SAM batteries.
Point defences would then be comprised of mixed batteries, clustered about the specific target to be defended. A typical structure for a point defence battery is a quartet of SA-9 or SA-13 SAM systems, complemented by a quartet of ZSU-23-4P mobile AAA systems. These would then be supplemented by singletons, pairs or quartets of the mobile, fully self-contained SA-8/Land Roll or Roland command link SAMs.
The intention of Soviet air defence strategists was to provide overlapping zones of coverage by various weapon types, thereby making it impossible for an aircraft to penetrate the area without encountering multiple types of SAM and AAA system. This was seen to be a means of maximising the demand placed upon Western ECM, thus forcing bigger ECM equipment at the expense of fuel and payload, while making it impossible to use any flight profile which could avoid the envelope of every weapon type.
While the exact composition of the Iraqi IADS and its deployment at the outset of the conflict may never be known, it is reasonable to assume that the Republican Guard would have operated the most sophisticated systems such as the European Roland SAM and SA-8 SAM, and some fraction of the SA-6 batteries, with the remaining mobile systems deployed by the Iraqi army to cover forces in Southern Iraq and Kuwait.
The static area defence SAMs were supplemented by a respectable quantity of AAA equipment, the heavier calibres supported by tracking radars such as the E-band Fire Can family of systems, or the newer I/J-band Flap Wheel series. The AAA was further supplemented by machine guns, hand held automatic weapons and man portable SAMs such as the SA-7B and SA-14, and the Chinese built HN-5A, a modified SA-7B with a cooled seeker.
This was by all means a formidable air defence system if used properly, and had the potential to inflict substantial attrition if not dealt with properly. The Allied response reflected this. In comparison with the Warpac and Western TVD PVO/PVO-VS IADS, the Iraqis lacked the latest weapons and some types such as the cumbersome SA-4 and SA-5 systems, but the high fraction of SA-3, SA-6 and SA-8 systems was easily comparable to the central European theatre. Since Soviet doctrine opposes forward deployment of the latest/best systems, it is fair to say the Iraqis had a representative implementation of the Soviet IADS as forward deployed in Eastern Europe. The results clearly reflected this.
REFERENCES:
[1] Zaloga S.J. 'Soviet Air Defence Missiles', Jane's Information Group, 1989
[2] 'International CounterMeasures Handbook', EW Communications and Cardiff Publishing, 1985, 1987, 1989, 1990.
Table 1 Iraqi Electronic Order of Battle