Introduction

The loss of Royal Air Force (RAF) Tornado ZG710 on 23 March 2003 was a tragic blue on blue incident during the second gulf war, and one of two similar incidents involving coalition ground based air defence (GBAD) within a matter of months. Returning to Ali Al Salem airbase after conducting a sortie in Iraq, ZG710 was incorrectly classified as an Anti-Radiation Missile (ARM) by a US Patriot battery and then, under self-defence rules of engagement (ROE), successfully engaged and destroyed. There is no single cause to this incident, rather it is a veritable 'swiss-cheese' effect where multiple issues compounded, resulting in the tragic loss of life. With the future fielding of the National Advanced Surface to Air Missile (NASAMS) system by 16 Regiment RAA, and the similarities in automation between Patriot and NASAMS, the lessons learned from this tragic engagement are pertinent in ensuring an incident like this doesn’t occur in an Australian context. It is important to note that all parties involved were operating in extremely trying and complex circumstances and acted with distinction. This author does not intend to discredit any persons involved. Rather, the aim is to learn from a tragic incident to ensure it doesn’t happen again. Therefore, this article will look to draw out those lessons learned by putting the incident in context, articulating what went wrong, and then drawing some conclusions that are hopefully helpful to the Integrated Air and Missile Defence (IAMD) community as well as the broader Australian Defence Force (ADF).

Context

The ZG710 incident on 23 March 2003 occurred during a complex period of conventional warfare. The coalition was conducting high intensity strikes against Iraqi targets using Air and Maritime platforms based both in and outside of the immediate AO. In addition to that, the Iraqi Armed Forces were conducting Ballistic Cruise Missile Attacks against Coalition targets and had an unknown capability to employ manned aircraft against coalition air forces. In response to these known and unknown threats, the US deployed 63 Patriot Air Defence Batteries to defend the coalition.[i] These batteries were deployed to defend a conventional force against conventional threats in a mid to high intensity conflict, exactly the situation NASAMs will be expected to operate in.

On the day, ZG710 was returning to Ali Al Salem airbase as part of a pair of aircraft having just completed a sortie in Iraq. Having been cleared by Air Traffic Control (ATC) to land, ZG710 was conforming to all promulgated Air-Space Control Measures (ACMs) and was in the process of descending when it was classified as an ARM and subsequently destroyed. The patriot battery responsible for the engagement tracked, re-interrogated and subsequently engaged the ARM track with a single missile in accordance with extant ROE and Tactics, Techniques and Procedures (TTPs). The time from ZG710 being classified as an ARM to its destruction by the patriot battery was three minutes. 

Lesson one: automatic systems will work within the parameters given to them

The first aspect that will be discussed is the automatic classification within the Patriot system. The symbol which appeared on the patriot radar screen indicated that an ARM was coming directly towards them. Having followed all the correct procedures, including Identify Friend or Foe (IFF) interrogation, the Tornado was mistakenly classified as an ARM, engaged and subsequently destroyed under self-defence ROE. How did a system that analyses the speed, range, altitude, angle of descent and the fact that the aircraft was operating in a pair classify ZG710 as an anti-radiation missile? The pre-programmed criteria placed into the patriot system were very broad, covering a global range of missile profiles, not just those present within Iraq.[ii] The impact of having such a broad threat profile was that ZG710 met those criteria as it commenced its descent into Ali Al Salem and triggered the commencement of the Patriot engagement sequence. The lesson here is the importance of ensuring that threat analysis and classification criteria matches as close as possible the known threat to maximise the accuracy of the system. This maximises the accuracy of the classification system and therefore increases confidence and effectiveness of the system. As with all threat assessments this will include constant monitoring and refining to ensure that it is as relevant as possible. With the introduction of NASAMs, and the range of spectrums this system will influence, this will require input from not only Army and Royal Australian Air Force (RAAF) but the complete Australian intelligence enterprise to produce the most complete, accurate assessment.

Lesson two: a system is only integrated if the nodes are properly connected

The second cause and lesson is the fact that the Patriot Battery was operating autonomously and yet did not have their full communications suite[iii]. The Patriot Battery’s digital communication equipment was still in transit from the US on the day of the incident, and as such contact with Battalion HQ and higher echelons was through a voice radio relay via a flanking battery.[iv] Digital systems are critical in allowing an Air Defence system to operate under anything but the strictest self-defence ROE. They provide an understanding to the crew of the airspace within the AO, awareness of friendly and enemy forces as identified by other forces in the area, and for digital airspace control means to be overlayed with the radar picture for battle tracking. The impact here is easily understood: the patriot crew did not have access to the complete picture of the airspace that they were operating in and therefore had reduced situational awareness. Had the crew had this information, including knowing that ZG710 was operating as part of a pair (the second aircraft had functioning IFF) and in accordance with promulgated ACMs, it is assessed that the crew would have been more likely to manually override the automatic classification and identify ZG710 as a friendly track and consequently not engage. The lesson here is that autonomous or independent operations requires requisite communications to ensure maximum situational awareness and to facilitate fully informed decisions.

Lesson three: ensuring rules of engagement are fit for task

The next aspect to be discussed is that of the Patriot Battery’s ROE and standing weapon control orders (WCO). The primary mission of the Patriot Battery was to defend ground troops from missile attack but with the inherent right to self-defence. Despite not having their full communications suite, and therefore severely reduced in their overall SA, the Battery was able to operate under a WCO of Weapons Tight. This WCO allows for the engagement of all targets identified as hostile; difficult to do when you don’t have access to the full picture with a beyond line-of-sight weapon system. The compounding issue is that the standing ROE at the time was broad enough for ZG710 to be classified as a hostile threat and therefore engaged by the Patriot Battery.[v] The lesson to be drawn from this component is that ROE for GBAD must be constantly reviewed to confirm that they are still appropriate to the task and that the WCO applied to each GBAD weapon system must be appropriate to the situation, inclusive of access to the widest possible air situational awareness.  

Lesson four: the importance of checking critical safety functions within an automated system

Despite the procedural and situational awareness issues, how did a coalition aircraft get classified as a hostile threat by a coalition GBAD system with the IFF technologies that existed at the time? Identify Friend or Foe is the military designation of the civilian Air Traffic Control system based on a challenge and response procedure to determine whether an aircraft is friendly or unknown. There are five modes of IFF which can work in parallel or alone, two of which are for both military and civilian, and three for strictly military use. In the invasion of Iraq, Mode 1 (an unencrypted code) and Mode 4 (an encrypted code) were used by coalition aircraft and GBAD systems.  Whilst ZG710’s crew followed all procedures at the time prior to and throughout their mission to check IFF functionality, these procedures did not include a positive challenge and response. It is therefore assessed that the Mode 4 IFF was not fully functional on the aircraft and therefore returned an 'unknown' response to the Patriot battery rather than the expected 'friendly'.  Additionally, the Mode 1 IFF codes on the Patriot Battery were not loaded, which meant that ZG710 was unable to be interrogated via this method.[vi]  The result of this is that there was no IFF circuit-breaker to prevent the automatic processes within the Patriot classifying ZG710 as hostile. The requirement to adjust IFF checks prior to take-off was implemented almost immediately in 2003, and the requirement to regularly check IFF functionality and correct load-out within all GBADWS will have greater importance with the increased automation capability within NASAMs.

Thoughts for the ADF

One of the key challenges that is going to face the ADF with the introduction of NASAMS is going to be the training of the crews, both enlisted and commissioned. Not only will they be required to understand how to operate the system, they will also be required to understand why the system is making certain recommendations, how that relates to the battlespace, and critically, when to question or reject system recommendations. In 2003, the crew was trained to implicitly trust the system and engage quickly[vii]. Specifically, the Tactical Control Officer (TCO) as the engagement authority had no access to additional information or training, and so was solely reliant on the system recommendation. Had the crew delayed their firing, it is likely that ZG710 would have been reclassified as its flight path continued; however, they had approximately one minute to decide whether to engage based off the threat picture at the time,  and while fully trained, their training had focused on generic threats rather than theatre specific threats or identifying false alarms. The US Army’s own assessment determined that the crew training focussed on rote battle drills and that Army training did not provide the Patriot crews with the expertise required for effective use. One of the lessons articulated was that inadequately trained operators, coupled with extensive automation, can result in a de-facto fully automated system[viii]. The important lesson here for the ADF is ensuring that the NASAMs crews are provided the adequate time and training to ensure they have the experience to be able to develop battlefield intuition and the confidence to safely maximise the strengths of the system.

Linked to the weaknesses in the training methodology, personnel practices within the US Army played a role in the loss of ZG710. Research conducted by the US Army Research Laboratory into the Patriot fratricide incidents from Gulf War Two identified that personnel turbulence within the patriot crews was a contributory factor, and that a large amount of this was attributable to the normal workings of the Army’s personnel system[ix]. Patriot and other technology-intensive systems require considerable operator and crew expertise for effective use. Developing this expertise takes several years of training and experience to reach the required levels of competence. However, the standard personnel practices within the US Army in regards to postings meant that Patriot crews simply were unable to reach the necessary level of expertise on the system. What will be a challenge for the ADF with the introduction into service of NASAMs will be balancing the requirements between our current general service officer and other ranks posting and career management system, and the clear requirements to spend a significant amount of time posted to the same position in order to reach the necessary level of expertise on the system. Arguably, there will be a requirement to accept that our current career management system in terms of developing profile and a broad range of experiences will not work for NASAMs. A model similar to that used by the AAAVn corps is a possible start point to allow for both career progression and developing the necessary expertise in the system.

Conclusion

NASAMs is an exciting and challenging step-change in the ADFs Ground Based Air Defence capability, partly because of its use of beyond line-of-sight fires and automation. NASAM brings a number of challenges, none of them insurmountable, as well as a huge range of opportunities. Through examining past failures, such as the downing of ZG710, the ADF can pre-empt systemic problems and incorporate the solutions into everyday 'best practice'. Some of the lessons identified in this article are:

1. The requirement to clearly understand the threat and any evolutions to enable accurate track classification
2. The requirement to have correct understanding of own operations, inclusive of any coalition forces
3. Ensuring the correct and complete equipment and communications load-out for all systems is used, and employment is adjusted if not available
4. The importance of robust communications testing prior to each mission including IFF
5. The importance of Mission Specific Training (MST) and crew training/experience on the system to improve proficiency to enable decisions rather than solely rely on the system recommendations
6. The importance of a Single Integrated Air Picture (SIAP) and its promulgation to all Airspace users
7. The requirement to adjust ROE/WCO when conducting Isolated GBAD operations
8. Ensuring that the level of training for TCO matches and enables their level of responsibility
9. Responsiveness v Accuracy. Ensuring that the speed of engagement matches the threat
10. The importance of being able to promulgate and display ACMs to inform decisions

Ideally by learning the lessons of those that have come before us we can successfully and efficiently bring this system into service. If we get this right, we can improve both the lethality and the safety of the ADF.