Putting the Enemy Back in CAS: An Argument for Flexible Tactics in Close Proximity

Putting the Enemy Back in CAS: An Argument for Flexible Tactics in Close Proximity

By Major E. Aaron Brady

Boar 81, we’ve got approval to strike the convoy you found. This will be Type 2 control, single GBU-38s, 30-second spacing, attack from the north. Your target is a column of vehicles near coordinates 123 456. Nearest friendlies are 40 kilometres east. Expect weapons clearance on final…

Introduction

The situation described above is becoming increasingly common in US and NATO air operations. Aircrew found a legitimate target in an area in which risk of fratricide is nil, yet the strike is being closely controlled by ground personnel hundreds of kilometres away via satellite radio and using Close Air Support (CAS) procedures. The trouble with this example – based on an actual occurrence during Operation INHERENT RESOLVE – Is that it illustrates the US military’s misapplication of CAS procedures to situations for which those procedures were not designed. This issue largely stems from two factors: a continued inability to resolve tensions inherent in operational frameworks (how we divide battlespaces up for command and control purposes) and weaknesses within United States and European doctrine that cleaves all air-to-surface operations against enemy military capabilities into either Air Interdiction (AI) or Close Air Support (CAS) categories.

The framework issue is discussed often, and therefore largely ignored in this article.[1] However, the doctrine issue remains mostly unaddressed. The main notable exception is a 2005 RAND study entitled Beyond Close Air Support.[2] More importantly, the flaws in the doctrinal models reflect deeper issues with the theoretical foundation western militaries use to understand air-to-surface operations. This article attempts to resolve this issue by presenting a more nuanced theory of counterland operations by examining the differences between the CAS mission and CAS procedures as well as addressing why this difference matters.

Understanding the purpose of CAS and the intent of CAS tactics, techniques, and procedures (TTPs) as codified in US Joint Publication (JP) 3-09.3 Close Air Support helps one recognise that CAS TTPs are intended to mitigate the risk of fratricide. However, the CAS mission is focused entirely on affecting an enemy in close support of a friendly land force. This, in turn, suggests that while many air actions may fall under the purview of the CAS mission, only a subset of these missions require the level of control typically used. The current poor understanding will create significant issues if the US or NATO fights a peer adversary. Ground commanders, Tactical Air Control Parties (TACP), and aircrew should foster a culture of flexible TTP application based on risk assessment to enable a more effective tempo depending on the specific operational environment.

AR.2002.115
Nicknamed the ‘Hun,’ the F-100 Super Sabre was possibly the best-known USAF close air support aircraft in the Southeast Asia War. Here, a forward air controller in an OV-10 directs these two F-100s in accurately delivering firepower in support of the ground forces. (Source: National Museum of the United States Air Force)

Examining Definitions of CAS

Determining what defines CAS as a mission begins with JP 3-09.3 Close Air Support, which views CAS as an action by fixed-wing or rotary-wing aircraft against targets in close proximity to friendly forces which require detailed integration of each air mission with the fire and movement of those forces.[3] The two key phrases most often keyed upon by CAS-focused communities like the TACP and A-10 tribes in the US Air Force are ‘close proximity’ and ‘detailed integration.’

Interestingly, the NATO definition of CAS includes the same definition almost word for word but adds that TTPs are executed ‘for fratricide avoidance and targeting guidance performed by a […] Forward Air Controller.’[4] British air and space power doctrine does not include detailed integration in its most basic definition but notes that ‘intensive air-land integration and coordination’ is necessary for fratricide prevention and target identification.[5]  Most other American allies match either the NATO or US definition. The US and its allies, therefore, agree that the mission of CAS is airstrikes in close proximity to ground forces and that detailed integration is needed. However, most allied doctrine notes explicitly that the purpose of detailed integration is to either mitigate fratricide risk or enable target correlation.

Close proximity is clearly a subjective term. Close means one thing to an infantry unit defending urban terrain and something entirely different to an armoured formation attacking through a desert. Doctrine even describes close as situational.[6] Likewise, detailed integration may encompass entirely different issues depending on the situation. So, even though these two clauses are the cited hallmarks of CAS, one cannot easily list out the explicit characteristics required to meet the conditions because they are too situationally dependent. JP 3-09.3 even states that when deciding if a mission should be considered CAS or not, ‘the word ‘close’ does not imply a specific distance […] The requirement for detailed integration because of proximity, fires, or movement is the determining factor.’[7] Therefore, even though proximity is considered one of the two main factors, the emphasis for describing CAS is detailed integration.

Three main elements drive a need for detailed integration: proximity, fires, or movement. These elements are multifaceted in the ways they influence air-ground integration. Proximity presents the most obvious issue in CAS: risk of fratricide. There is also a risk to the aircraft due to their proximity to surface-based fires which requires mitigation. Proximity further mixes with fires and movement to suggest another theme not mentioned in any of the definitions. Airstrikes occurring within a land commander’s area of operations (AO) may have a considerable impact on future actions by the effect those strikes may have on the enemy, the terrain, or civilians. These effects might be long-term, such as the destruction of crucial infrastructure or critical damage to military equipment, or short-term like the psychological effect of a large airstrike on an enemy unit. In either case, the land commander must both approve the strikes – in a sense ‘buying’ the effects of the attack – and ensure that the effects facilitate the overall operation. Considering fires and movement, the intent of CAS is to strike targets that directly enable the land scheme of maneuver. Doctrine hints at some of these points. This discussion highlights a weakness prevalent in all the doctrinal definitions of CAS that feeds into the misunderstandings throughout the US and allied forces: the definitions describe what CAS is, not the purpose of CAS. This is due in no small part to the way that most doctrine organises the various missions of air power.

The Counterland Doctrinal Framework

Once again, there is a large degree of consensus between the US and its allies over air power’s mission structure. US JP 3-0 Joint Operations simply classifies most air power missions within the various joint functions; most of the subjects discussed in this essay naturally fall under fires. In contrast, NATO doctrine creates a hierarchy of air missions. Air attack encompasses most missions which directly influence an enemy. One subset of attack is counter-surface force operations, under which falls air power contribution to counterland operations, which in turn incorporates two missions: AI and CAS.

UK doctrine closely aligns with NATO thinking. The US Air Force theory lies between the US joint doctrine and European concepts. It describes all-action intended to influence an enemy’s land forces as counterland which includes just two sub-missions: AI and CAS. The US Marine Corps presents a slightly different perspective. Marine thinking classifies six functions of Marine aviation, one of which is offensive air support (OAS). OAS incorporates CAS and deep air support (DAS), which includes AI, armed reconnaissance, and strike coordination and reconnaissance (SCAR). Of note, Marine doctrine states explicitly that ‘detailed integration is accomplished using positive control’ and that ‘positive control is provided by terminal controllers [JTACs].’[8] This listing shows that, except for US joint and Marine Corps doctrine, militaries tend to organise CAS and AI under a broader counterland concept (see Figure 1). Therefore, most US and NATO service members view CAS as a subset of a counterland concept.

Doctrine Models (JPG)
Figure One

CAS, as shown earlier, occurs close enough to friendly land forces that strikes require detailed integration. AI – the other half of counterland operations – occurs far enough away that this level of integration is unnecessary. Adopting a more conceptual view, the larger counterland mission set is enemy-centric – any counterland mission focuses on affecting an enemy’s combat system. AI and CAS, though, are friendly-centric – the doctrinal difference between the two lies in the level of integration mandated by the proximity of friendly land forces. Harkening back to the earlier identification of fratricide risk as to the primary reason demanding detailed integration with target nomination as a close second, we arrive at the crux of the issue.

To solve these two problems, CAS is differentiated from AI in that while executing CAS, aircrew does not have weapons release authority. By mandating that the land force commander must approve target nomination and weapons release and because the land commander is the authority for expenditure of weapons in the assigned area of operations, the various systems seek to resolve the two critical issues associated with airstrikes near friendly land forces. This clarification enables one to define the purpose of the CAS mission while still acknowledging the characteristics that separate it from AI.

The Purpose of CAS: A Mission-Based Definition

CAS is an air mission flown in close support of land forces to disrupt, degrade, or destroy enemy forces. These enemy forces are in close enough proximity to friendly land forces that risk mitigation mandates detailed coordination between the air and land forces. This definition does not roll off the tongue as easily as the current definition in JP 3-09.3 but does address both what the CAS mission is in addition to its characteristics and requirements. By creating a definition that addresses the purpose of CAS, we introduced the key elements that form the basis for CAS procedures.

Evaluating CAS Tactics, Techniques, and Procedures

CAS TTPs intend to mitigate the risk of fratricide and integrate air effects into a larger fire support plan by efficiently nominating, correlating, and approving weapons release against targets. A process termed Terminal Attack Control accomplishes this goal, hence the name for the person that controls CAS strikes, the JTAC. Standardised communication – most notably the CAS Briefing, referred to as the 9-Line – and specific weapons release authorities and parameters combine to achieve the overall intent. Compared to defining the purpose of CAS, deducing what CAS TTPs intend to do is simple. However, two major presumptions within the CAS TTPs are not readily plain and may cause issues in a large-scale conflict. These concerns drive the overall conclusion that there is a disconnect between the intent of CAS and the procedures laid out in current doctrine.

First, CAS procedures are almost entirely reactive. One can argue that planned CAS is an exception to this, but two factors reduce the strength of this claim. In this author’s decade of experience practising CAS, preplanned missions were far and away the exception rather than the norm. Mike Benitez’s article ‘How Afghanistan Distorted CAS’ shows that my experience is typical. Further, unless the plan includes detailed restrictions and weapons release authority, TACP and aircrew must still resort to using the entirety of CAS TTPs even during a planned mission. Nevertheless, in my experience reactive TTPs are so ingrained that even when strikes are planned in detail, both the controllers and aircrew have difficulty merely executing the plan. Decades of experience in the Middle East created a sense within the minds of both parties that 9-Lines need to be passed and confirmed on the radio even if there are no changes to the plan.

In stark contrast to aircrew performing AI, there is a limited ability within this paradigm for CAS aircrew to exercise initiative during battle. Since CAS is doctrinally a form of fire support, at first, this seems reasonable. However, on closer inspection, it should cause concern for several reasons. None of the doctrinal models with the notable exception of JP 3-0 specifies CAS as a form of fire support – it is air attack against land forces near friendly forces. This suggests that either the doctrinal models are flawed or that CAS is a distinct mission that happens to provide fire support, not a fire support mission that happens to be conducted by aircraft. Putting that point aside, ground-based fire support may conduct any number of missions with some level of internal initiative. Artillery raids or counter-battery fire are two examples. Further, harkening back to the doctrinal model point, CAS is quite different from other forms of fire support.

If lethal fire support for land maneuver is broadly divided into the categories of CAS and artillery, note that virtually all forms of artillery employ indirectly. That is, the artillery crew aimed at a location derived and passed from another source. CAS aircrew, on the other hand, receives target information from the JTAC and aim or guide the munitions themselves. Apart from bombing on coordinates, a technique not commonly used, CAS aircrew perform the aerial equivalent of aiming a rifle at the assigned target. Thus, even though they might be dropping a bomb from several miles distant, the aircrew is employing a direct-fire system as compared to other, indirect forms of fire support.

This distinction is significant because it shows that in many cases aircrew, unlike artillery operators, have the capability to find their own targets independent of specific target nominations from a controller. In recent years, CAS practitioners even added guidance to the doctrine explaining how CAS aircrew could nominate a target to a JTAC then receive a nomination and weapons release authority for the same target.

Going back to the concept of reactivity, one should now see the first issue clearly. CAS procedures, as an adjunct of fire support procedures, are inherently reactive. However, aircrew, unlike artillery operators, can identify targets independently. Therefore, the possibility exists that CAS can be performed proactively, given the right circumstances and presuming risk to friendly forces is mitigated. This suggests that the doctrinal models are correct: CAS is a distinct counterland mission that has fire support characteristics but is not inherently a fire support mission that happens to be performed by aircraft. If one accepts this notion, then we necessarily come to the second presumption behind extant CAS doctrine.

The reactive nature of CAS rests on the idea that detailed integration and risk mitigation are best accomplished through the close control of individual targets and, in most cases, individual attacks. This may be proper in many cases. In some cases, though, a single target or target set may require multiple attacks. This notion is part of the rationale behind Type 3 control in current doctrine, in which the land force commander approves multiple strikes on the same target. This type of control is still inherently reactive. However, with enough planning and an appropriate command and control capability, forces may be able to conduct CAS with a level of initiative unheard of today. Therein lies the problem with the mindset prevalent in the US military today.

A-10 Aerial Refueling
A-10 Thunderbolt II aircraft conduct a combat air patrol mission over an undisclosed location in Southwest Asia, 21 September 2019. (Source: US Department of Defense)

The Grey Area between AI and CAS

While the earlier discussion showed that all counterland missions are inherently enemy-centric, but the difference between CAS and AI revolves around friendly land dispositions. AI is performed in areas in which the risk to friendly land forces is nil and therefore, only minimal integration is required. CAS, on the other hand, is performed in areas where the risk of fratricide exists and detailed integration into the land fires scheme is required. In practice, this means that battlespaces are cleanly divided into AI and CAS areas by the Fire Support Coordination Line (FSCL). Virtually any US doctrinal manual that discusses the FSCL conveys that the FSCL is not a dividing line between AI and CAS TTPs, but instead ‘delineates coordination requirements for the joint attack of surface targets.’[9] The line is closer to a command and control border than anything else. However, for all intents and purposes the mindset discussed at length that aircraft operating within a land component area of operations are conducting CAS, the FSCL becomes a border between AI and CAS areas. While joint doctrine attempts to negate this thinking.

Accepting the argument regarding CAS TTPs are inherently reactive, one sees how the FSCL creates a zone where aircraft can operate proactively and a second zone in which aircraft must function entirely reactively. The problem is the size of the second zone. During the major combat phase of Operation IRAQI FREEDOM, the US Army often placed the FSCL more than 100 kilometres from friendly troops.[10] Obviously, friendly forces were at basically zero risks of fratricide if aircraft struck targets that far away. Additionally, most surface-to-surface fires were shot at targets well short of that distance.

Recent Warfighter exercises indicate that FSCLs today are often placed about thirty to 40 kilometres from the friendly lines.[11] Even in this battlefield geometry, there is still a sizeable portion of the battlespace between the friendly front and the FSCL in which the risk of aircraft causing fratricide is minimal. This article does not address the operational framework concerns raised by this example, i.e., where should the line be, or should there be other coordination lines? Instead, this author posits that regardless of how a force organises a battlespace there will be a grey area.

This grey area is entirely subjective and based on the context of each individual battlespace. When analysing a battlefield, one can usually clearly lay out the areas near friendly troops where CAS procedures must be used to mitigate risk to friendly forces and integrate air strikes into the larger fires plan. One can also clearly see the areas in which no risk is present to friendly troops and the need for detailed integration into the fires plan is nil – the AI area. However, there will be many areas on the map that do not fit neatly into either category. These areas might be far enough away from friendly troops that fratricide risk is low but still close enough that detailed integration is required to deconflict aircraft with surface-to-surface fires.

Alternatively, there might be areas that, due to the nature of the terrain or the friendly scheme of maneuver, are relatively close on the map (say within a few kilometres) but the risk of fratricide is nevertheless quite low. These two simple examples illustrate the notion that between CAS and AI is a nebulous area that can be found in many battlespaces. The pressing concern for US and NATO CAS practitioners is to learn to conduct proactive CAS in these grey areas to achieve the purpose of CAS while retaining enough control to accomplish the intent of current CAS TTPs.

Finding Solutions to Enable Proactive CAS

The extant CAS paradigm relies on the idea that CAS fires must be reactive. A reactive mindset, however, is not conducive to success in a modern battlespace in which the speed of decision-making is paramount. The paradigm should allow for aircrew to proactively achieve the purpose of CAS – disrupting, degrading, and destroying enemy forces per a land maneuver commander’s intent and with minimal risk to friendly forces. The 2019 US JP 3-09 Joint Fire Support identifies the criticality of fast-paced decision-making in modern combat, emphasising that joint fire effects are best achieved through ‘decentralized execution based on mission-type orders.’[12] A myriad of options to do this is already within US doctrine.

The joint force could incorporate the US Marine Corps concept of the Battlefield Coordination Line into joint doctrine. This line allows land commanders to simply denote where the risk to friendly forces is low enough to justify AI TTPs. Whether land commanders and TACP utilise preplanned 9-Lines with Type 3 control, engagement areas with specific restrictions attached, or even restricted fire areas, the possibilities for enabling initiative to abound. If targets appear outside those areas, or the ground situation changes, then switch to close control of individual attacks. Nonetheless, in large conflicts, allow CAS aircrew to achieve the intent of CAS by providing enough freedom of action to enable initiative. US forces should foster a mindset that emphasises the concepts of mission command and decentralised execution – delegate decision-making authority to the lowest appropriate level. The simple fact is that US forces in all domains must make decisions faster than the enemy. A reactive CAS mindset virtually ensures a slow decision cycle. A proactive perspective, with proper risk mitigation, allows for thinking aircrew to engage the enemy faster with commensurate effects on the enemy’s tempo.

Conclusion

In summary, let’s review the key takeaways. First, counterland missions affect an enemy’s land military capabilities and consist of AI and CAS subsets. The only difference between these two is that CAS is executed in close proximity to friendly forces while AI is distant enough that detailed integration is not needed. Second, the purpose of CAS TTPs is to facilitate target nomination and mitigate risk to friendly ground troops. Third, the current US mindset is that a CAS mission must be controlled using individual 9-Lines for every target regardless of actual risk to friendly forces. The disconnect between the first two points and the third point creates a potentially dangerous concoction for CAS effectiveness during future major conflicts.

Land commanders, TACP, and CAS aircrew should train now to using various control methods to enable initiative on the part of aircrew. Whether that means more sophisticated uses of fire support coordination measures or learning to transition between CAS and AI TTP control methods flexibly is irrelevant. The point is to learn now, on bloodless training grounds, how to delegate initiative to the lowest levels to make decisions as rapidly as possible. The lessons learned today at Combat Training Centers and countless air-to-surface ranges around North American and Europe concerning how to conduct proactive CAS missions will pay dividends in a potential future conflict.

Major E. Aaron ‘Nooner’ Brady is a student at the US Army’s School of Advanced Military Studies. He graduated from the US Air Force Academy with a BS in History in 2006. He is a graduate of the US Air Force Weapons School A-10 course and is a senior pilot with more than 1,800 hours including more than 360 combat hours.

Header Image: A US Air Force A-10 Thunderbolt II maneuvers through the air during Red Flag-Alaska 19-2 at Eielson Air Force Base, Alaska, June 17, 2019. The exercise provides counter-air, interdiction and close air support training in a simulated combat environment. (Source: US Department of Defense)

[1] Mike Benitez, ‘How Afghanistan Distorted Close Air Support and Why it Matters,’ War on the Rocks, 29 June 2016; Clay Bartels, Tim Tormey, Jon Hendrickson, ‘Multidomain Operations and Close Air Support: A Fresh Perspective,’ Military Review, 97:2 (2017), pp. 70-9.

[2] Bruce R. Pirnie, Alan Vick, Adam Grissom, Karl P. Mueller, David T. Orletsky, Beyond Close Air Support: Forging a New Air-Ground Partnership (Santa Monica, CA: RAND Corporation, 2005).

[3] Joint Publication (JP) 3-09.3 – Close Air Support (Washington DC, US Joint Staff: Department of Defense, 2019), p. I-1.

[4] Allied Joint Publication 3.3(B) – Allied Joint Doctrine for Air and Space Operations (North Atlantic Treaty Organization, Standardization Office, 2017), p. 1-11.

[5] Joint Doctrine Publication (JDP) 0-30 – UK Air and Space Power, Second Edition (Shrivenham: Defence Concepts and Doctrine Centre, 2017) p. 34

[6] JP 3-09.3, p. I-2.

[7] Ibid.

[8] Marine Corps Reference Publication 1-10.1 – Organization of the United States Marine Corps (Washington DC:, Department of the Navy, 2016), p. 6-1.

[9] JP 3-09, Joint Fire Support (Washington DC: Department of Defense, 2019), p. A-5.

[10] Pirnie et al, Beyond Close Air Support, p. 68.

[11] Travis Robison and Alex Moen, ‘Reinventing the Wheel: Operational Lessons Learned by the 101st Division Artillery during Two Warfighter Exercises,’ Military Review, 96:4 (July-August 2016), p. 75.

[12] JP 3-09, Joint Fire Support, p. IV-1.

Call for Submissions: Bombing to Win Revisited

Call for Submissions: Bombing to Win Revisited

In 2020, From Balloons to Drones will run a series of articles that examine the use and development of air strikes from the earliest use of air power through to today.

The use of air power to achieve an effect on the ground and at sea remains controversial. For example, with regards to strategic bombing, Robert Pape argued in Bombing to Win that it ‘did not work’ as a military strategy. Moreover, since the inception of air power, there have been ongoing legal and ethical debates about the use of air strikes in various spheres of military activity. As such, From Balloons to Drones is seeking submissions for a series of articles that examine the varied use of air strikes, both kinetic and non-kinetic, at the tactical, operational and strategic levels of war. Themes to be explored might include, but are not limited to:

Strategy, Theory and Doctrine | Organisation and Policy | Roles

Operations – Kinetic and Non-Kinetic | Tactics, Training and Procedures

Strategic and Operational Effect | Technological Developments

Culture | Ethical and Moral Issues

National, International and Transnational Experiences

We are looking for articles of c. 3,000 words, though we will accept larger pieces and we reserve the right to publish them in parts. We welcome and encourage submissions from academics, policymakers, service personnel, and relevant professionals. We also welcome submissions written from diverse academic disciplines.

We plan to begin running the series in January 2020, and it will continue for as long as we receive potential contributions. We will also be looking at publishing extended versions of selected articles in an edited volume.

Submissions should be submitted in Word format and emailed to the address below with ‘SUBMISSION – Bombing to Win Revisited’ in the subject line. Also, please include a 50-100-word biography with your submission. Footnotes can be used, and please be careful to explain any jargon. However, if you are not sure if your idea fits our requirements, then please email us with ‘POTENTIAL SUBMISSION – Bombing to Win Revisited’ in the subject line to discuss.

If you are interested in contributing, please email our editor, Dr Ross Mahoney, at airpowerstudies@gmail.com or via our contact page here.

Header Image: B-52Ds from the Strategic Air Command line up for takeoff as they prepare for strikes over Hanoi and Haiphong, North Vietnam, during Operation LINEBACKER. (Source: National Museum of the USAF)

Air Power and the Battle of Hamel

Air Power and the Battle of Hamel

By Dr Michael Molkentin

Editorial Note: The 4th of July 2018 represented that 100th Anniversary of the Battle of Le Hamel. While Hamel was important, its place as a model on which subsequent operations were based has been overplayed. Furthermore, notable popular Australian historians have also distorted the significance of the battle. Nevertheless, as Dr Michael Molkentin highlights in this article, Hamel was valuable in highlighting the evolution of, and the diverse roles played by, air power in support of land battles during the First World War.

In the historiography of the First World War, the Battle of Hamel (4 July 1918) has frequently been cited as an example of significant tactical innovation and a ‘model’ on which subsequent British offensive operations were planned. While neither interpretation bears up to scrutiny when the battle is viewed within the broader context of British Army operations on the Western Front, relative to its size the Australian Corps’ capture of Hamel integrated air power to a hitherto unprecedented extent and, in hindsight, provides a revealing case study of the varied, distinct and specialist air power roles that had evolved during the conflict.

The Australian Corps’ headquarters, commanded by the recently appointed Lieutenant-General Sir John Monash, planned the capture of the village of Hamel (located south of the Somme) as a line-straightening operation. Besides the troops of his own corps’ 4th Division, Monash had ten infantry companies from the US 33rd Division, 60 tanks from the British 5th Tank Brigade (including the new Mark V tank) and 639 artillery pieces. Monash planned to launch a surprise assault behind a creeping barrage and tank screen (much like British Third Army had done at Cambrai the previous November); he anticipated that his infantry could secure their objectives – two kilometres deep on a seven-kilometre wide front – within an hour and a half.

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A unique photo of a disabled British RE8 aircraft diving towards earth during the 4th Australian Infantry Brigade attack at Vaire Wood in the Battle of Hamel. It was subsequently discovered that the machine had been hit by a presumably faulty shell. (Source: Australian War Memorial)

Monash’s staff also worked with the Royal Air Force’s (RAF) V Brigade to organise substantial and multi-layered air support for the operation. The Australian Corps’ corps squadron, No. 3 Squadron Australian Flying Corps (AFC), would conduct the ‘majority of the tactical work’ during the battle. Its airmen would maintain a continuous presence over and directly beyond the battlefield to follow the progress of the Australian infantry (contact patrols), watch for enemy counter-attacks (counter-attack patrols), identify and direct artillery fire onto active German batteries (artillery patrols) and to photograph the new front line once it had been secured. New maps would then be produced and issued to troops in the front line within a matter of hours.[1] Assisting No. 3 Squadron with providing tactical air support, the RAF’s No. 8 Squadron would co-operate with the tanks while No. 9 Squadron parachuted ammunition to troops at their objectives. The night-bombers of No. 101 Squadron flew above the staging area on the night before the battle to mask the noise of the tanks as they moved up to their starting line.

The squadrons of 22nd (Army) Wing were also assigned to support the land battle: three of its four fighter squadrons would fly ground-attack sorties while its Bristol Fighter unit watched roads, railways and debussing points as far east as Proyart (10 kilometres east of Hamel). The army wing’s two bomber squadrons would meanwhile raid known German bivouacs. This aspect of the air plan reflected the RAF’s preference for interdiction over ‘trench strafing’ – the belief being that it was better to harass German troops and artillery behind rather than on the battlefield itself.[2] GHQ allocated three additional fighter squadrons from, IX Brigade, the RAF’s strategic reserve, to provide air superiority and the neighbouring Third Army’s fighters extended their offensive patrols south to cover the rest of Fourth Army’s front.[3]

Probably no other division-sized operation of the war enjoyed the combined support of aircraft from three wings, that is, 13 squadrons, or 230-odd aircraft. As well as the multi-faceted and highly integrated function that air power had assumed by this stage, the air plan, devised by the Australian Corps’ BGGS in collaboration with V Brigade illustrates the British Army’s growing reliance on machinery and firepower to reduce casualties and compensate for dwindling manpower.[4]

As the plan dispensed with a preliminary bombardment, No. 3 Squadron’s artillery spotting began at zero hour. For the first few hours, airmen reported batteries neutralised by the barrage so that artillery commanders could switch their guns onto active targets. The plan also allocated five heavy batteries to answer zone calls, airmen being briefed on where the Germans might move batteries once the battle started.[5] No. 3 Squadron issued 80 zone calls and co-operated in the neutralisation of at least 17 batteries (‘in many cases’ airmen did not see the artillery’s response to zone calls).[6] Although not entirely preventing it, the Australian Corps counter-battery arrangements suppressed the German artillery’s response adequately during the advance and consolidation.[7]

Counter-attack patrols flew beyond the German lines to ‘an unheard of distance’ with instructions to transmit zone calls on concentrations of German troops and engage them with bombs and machine guns.[8] One crew reported a concentration of enemy infantry just before 0700 but otherwise, seeing no enemy counter-attacks the airmen, as Lieutenant Arthur Barrett put it, ‘bombed and machine gunned everything we saw.’ Crossing the line just after zero hour he and his pilot halted a train, silenced several machine gun positions and strafed a pair of limbered guns, overturning one. Descending below 300 feet, Barrett’s eyes ran from gas in the barrage.[9] 3rd Squadron’s airmen dropped 138 bombs and fired 9,500 rounds on 4 July 1918.[10] Combined with the record 54,000 rounds and 850 bombs expended by 22nd Wing’s fighter pilots, this had a considerable impact on such a narrow battlefront.[11] ‘Several’ prisoners attested to the ‘moral effect’ of air attacks and noted how:

[t]hey prevent men getting machine guns into action almost as effectively as a barrage […] it was almost impossible to look over the top without getting machine gunned from the air.[12]

Corroborating this is German Second Army orders that noted ‘heavy casualties caused by machine gun fire from low-flying enemy machines’ at Hamel and issued instructions for dealing with British aircraft.[13]

Although Australian infantry had been signalling to aircraft since operations at Poziéres in 1916, contact patrols represented a new role for 3rd Squadron at Hamel. Despite difficulties experienced during the 1916-17 campaigns, the general staff recognised that aircraft provided the shortest possible passage of information from the battlefield to corps (and, atypically at Hamel, divisional) headquarters.[14] Dropped by airmen returning from the line, contact patrol reports reached headquarters staff in 24 minutes on average – up to half the time taken by a wireless message and a third of that usually taken by carrier pigeon.[15] Experience indicated that staff needed to synchronise contact patrols with the infantry’s timetable carefully. At Hamel, No. 3 Squadron had instructions to call for flares on the objective at 90 minutes after zero.[16] No. 8 Squadron followed the tanks across the battlefield and ‘in one or two cases were able to give information as to those which had been put out of action.’[17] The infantry’s clockwork progress and minimal resistance at the objective allowed the infantry and tanks to respond ‘well’ when contact patrol pilots sounded their klaxon horns; the airmen delivered ‘exceedingly accurate’ reports.[18] It remained to be seen, however, how the system would cope during running battles and exploitation operations when it would be arguably more crucial for staff to keep track of their troops.

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A parachute, used as an ammunition carrier, caught in the trees at Vaire Wood, during the Battle of Hamel on 4 July 1918, when the supply of ammunition to the infantry by means of parachutes was a feature of aircraft cooperation. The picture was taken the day following, during shelling by the enemy of newly won Australian positions. (Source: Australian War Memorial)

For the first time, at Hamel, the RAF organised battlefield resupply using equipment designed and built at No. 3 Squadron’s aerodrome under the direction of ‘B’ Flight’s commander, Captain Lawrence Wackett. The idea apparently came from the Luftstreitkräfte’s (German Air Service) attempts at dropping ammunition to troops on the battlefield during the spring offensives.[19] At Hamel a detachment from No. 9 Squadron carried out the work, dropping 111,600 rounds to Australian troops at their objectives and at dropping stations close behind the line.[20] Endorsing Wackett’s claim for a £1,000 inventor’s fee from the British government (he received £350), Monash declared the scheme ‘an unqualified success’, noting how it permitted the rapid resupply of troops in ‘isolated and exposed positions’ and saved casualties among carrying parties.[21] His subordinates, though more prosaic, also indicated the trial’s success. 4th Australian Infantry Brigade’s CO described it as working ‘satisfactorily’ while 6th Brigade’s commander noted how the scheme ‘worked very well,’ delivering ammunition within 10 yards of one machine gun position.[22] Though faster, aircraft lacked the carrying capacity of other transportation available to the Australian Corps: a single tank could deliver four times as much ammunition as each of No. 9 Squadron’s aircraft, plus 300 grenades, 450 litres of water and a vast quantity of food and other trench stores.[23] Employed in all subsequent British offensives (the RAF delivered 30-60,000 rounds each day during the Amiens offensive), ammunition drops by corps squadrons thus remained an ‘emergency’ adjunct to other forms of battlefield logistics.[24]

The RAF’s tactical support was enabled, to a substantial extent, by the air superiority that British airmen exercised over the battlefield. Throughout the day, the fighter squadrons of 22nd (Army) Wing and three additional fighter squadrons attached from IX Brigade, ranged east of the battlefield to intercept any German aircraft that attempted to interfere. It was RAF policy to employ air superiority patrols offensively, east of the lines, rather than as a protective screen or close escorts. The airmen of the Luftstreitkräfte made no sorties over the Hamel battlefield until 9.30am – some five hours after the Australian infantry had secured their objective line. German fighters after that became ‘fairly active’ over the area, and there were ten air-to-air combats. In the largest of these, the SE5as of No. 24 Squadron engaged a mixed formation of 20 Fokker DVIIs, Pfalz scouts and Albatros DVs over Cerisy, six kilometres east of Hamel. The British pilots claimed three enemy aircraft and lost none themselves.[25] It is noteworthy that No. 24 Squadron was one of the 22nd (Army) Wing fighter units allocated to bomb and strafe targets on the ground behind German lines – its involvement in this dogfight illustrates the integration of air superiority and interdiction roles that British airmen had begun to undertake at Third Ypres the previous year.

Altogether, of the hundreds of sorties flown by the RAF in support of the Hamel operation, only three resulted in the loss of an aircraft to air combat– and only one of these involved one of the aircraft involved in direct tactical support over the battlefield. All other British losses resulted from ground fire, to which the pilots of low-altitude contact patrols and ammunition drops, were considered vulnerable.[26] The RAF’s efforts to maintain air superiority, therefore, appear to have been overwhelmingly successful – although the woeful deficiencies in material (especially fuel) that the Luftstreitkräfte faced in the summer of 1918 need to be recognised when evaluating the success of the British air plan.

4093525
The remains of RE8 C4580, which was shot down at Hamel Wood, by the enemy, after it had succeeded in dropping ammunition to the forward troops by means of parachutes. This aircraft was flown by No. 9 Squadron RAF during the Battle of Hamel and used for ammunition drops to the forward troops. (Source: Australian War Memorial)

The Battle of Hamel, therefore, indicates the extent and sophistication to which the application of British air power in support of surface operations had evolved during the First World War. The efforts of British airmen to support of Monash’s troops were not only extensive but organised carefully, through a variety of distinct air power roles, to provide a range of tactical and operational-level services that, considering the aircrafts’ technical limitations, functioned effectively. Indeed, the operation represented the high-water mark of efficacy in air-ground cooperation in the British Expeditionary Force during the First World War. As a limited, set-piece battle, Hamel drew on structures, procedures and technologies that had evolved during four years of trench warfare. Subsequent British operations during the ‘Hundred Days’, in which exploitation and pursuit replaced carefully planned set pieces, would test this system of integrating air power with surface forces and in some respects undermine the efficacy of British close air support. The war’s final battles would, in some respects, force airmen to begin their ‘learning curve’ all over again.[27]

Dr Michael Molkentin is a head teacher at Shellharbour Anglican College and an adjunct lecturer at the University of New South Wales Canberra. He has a PhD in History from the University of New South Wales and is the author of three books, including Australia and the War in the Air (OUP, 2014). His next book, a biographical history of Sir Ross Macpherson Smith and the 1919 England to Australia air race will be published in 2019.

Header Image: An R.E.8 aircraft, serial number A3662, ‘J’, presented to the Australian Flying Corps by Mr H. Teesdale Smith of Adelaide, South Australia. This was the type of aircraft used by No. 3 Squadron AFC at the Battle of Hamel. (Source: Australian War Memorial)

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[1] Australian War Memorial (AWM), Canberra, AWM4 8/6/19 Part 1, 3rd Squadron War Diary, 4 July 1918.

[2] For a clear expression of this idea, see the Royal Flying Corps’ plans for defence in the German spring offensives: H.A. Jones, The War in the Air: Being the Story of the Part played in the Great War by the Royal Air Force, Vol. IV, (Oxford: The Clarendon Press, 1934), p. 445.

[3] The National Archives (TNA), London, AIR1/677/21/13/1887, Air Historical Branch, The Western Front Air Operations, May-November 1918, pp. 54-5.

[4] TNA, AIR1/1592/204/83/17, Brigadier-General Thomas Blamey, BGGS Australian Corps to GOC 4th Australian Division and GOC V Brigade RAF, 29 June 1918; Gary Sheffield, Forgotten Victory: The First World War – Myths and Realities (London: Review, 2002), p. 236.

[5] AWM, AWM26 364/12, Counter-battery Australian Corps HA Operation Order No. 7, 1 July 1918.

[6] AWM, AWM4 8/6/19 Part 1, 3rd Squadron war diary, 4 July 1918; TNA, AIR1/1009/204/5/1289, RAF Headquarters, Notes on corps squadrons work on the First and Third Army fronts during recent operations, 14 September 1918.

[7] AWM, AWM4 1/48/28 Part 1, 4th Division general staff war diary, 4 July 1918. The divisional staff noted that enemy artillery was ‘not very active’ and that retaliation against the Australian barrage was ‘weak’.

[8] AWM, AWM 2DRL/0053, Lieutenant Arthur Barrett to mother, 30 August 1918.

[9] AWM, AWM 2DRL/0053, Barrett to mother, 30 August 1918.

[10] AWM, AWM4 8/6/19 Part 1, 3rd Squadron war diary, 4 July 1918.

[11] TNA, AIR1/1592/204/83/17, CO 22nd Wing RAF, ‘Summary of Operations’, 11 July 1918.

[12] TNA, AIR1/2124/207/74/3, Summary of air intelligence, 18 July 1918; AWM, AWM4 8/14/2, RAF Communiqué No. 15, 17 July 1918.

[13] TNA, AIR1/2124/207/74/3, Summary of air intelligence, 18 August 1918.

[14] General Staff, SS 205 – Notes on Observation from Aeroplanes (France: Army Printing and Stationary Services, February 1918), p. 10; AWM, AWM4 8/6/18, Captain Errol Knox, recording officer, 3rd Squadron to 3rd Squadron flight commanders, 3 July 1918.

[15] Jonathan Boff, ‘Air/land integration in the 100 Days: the case of Third Army’, RAF Air Power Review, 12:3 (2009), p. 82.

[16] AWM, AWM4 8/6/18, Knox to 3rd Squadron flight commanders, 3 July 1918.

[17] TNA, AIR1/677/21/13/1887, Air Historical Branch, Western Front air operations May-November 1918.

[18] AWM, AWM4 8/6/19 Part 1, 3rd Squadron war diary, 4 July 1918.

[19] F.M. Cutlack, Official History of Australia in the War of 1914-1918: Volume VIII – The Australian Flying Corps in the Western and Eastern Theatres of War, 1914-1918 (Sydney, NSW: Angus and Robertson, 1939 [1923], p. 272; EML Gorrell papers, Series M, Item 14, GHQ AEF, Summary of Air Information, No. 29, 19.6.18.

[20] AWM, AWM4 8/6/19 Part 1, 3rd Squadron war diary, 4 July 1918.

[21] AWM, AWM10 43/13, Lieutenant-General John Monash, GOC Australian Corps to The Royal Commission on Awards to Inventors, 13 May 1919.

[22] AWM, AWM4 23/4/34 Part 1, Fourth Australian Infantry Brigade Intelligence Summary, 6am 3.7.1918 to 6am 4.7.1918; AWM4 23/6/35 Part 1, Brigadier-General J. Paton, CO 6th Australian Infantry Brigade, Preliminary Report on Operations of 6th AI Brigade on 4-7-1918.

[23] AWM, AWM4 1/48/29 Part 3, Fourth Australian Division Report on Operations- August 7th to August 10th 1918.

[24] Jones, The War in the Air, Vol. VI (1937), p. 484; TNA, AIR1/1009/204/5/1289, RAF Headquarters, Notes on corps squadrons work on the First and Third Army fronts during recent operations, 14 September 1918; TNA, AIR1/1591/204/83/8, 15th Wing Operation Order No. 112, 17 September 1918.

[25] AWM, AWM4 8/14/2, Royal Air Force Communique No. 14, 10 July 1918.

[26] Trevor Henshaw, The Sky their Battlefield II: Air Fighting and Air Casualties of the Great War, (London: Fetubi Books, 2014), p. 187.

[27] This argument is expanded in Michael Molkentin, Australia and the War in the Air (Melbourne: Oxford University Press, 2014), pp. 196-206.

A Forgotten Revolution? RAF Army Co-operation Command and Artillery Co-operation

A Forgotten Revolution? RAF Army Co-operation Command and Artillery Co-operation

By Dr Matthew Powell[1]

Jonathan Bailey wrote that the First World War was the time of a true revolution in military affairs about the development of artillery firing.[2] One of the first significant developments that took place was the creation and refinement of the ‘clock code’ system.[3] Using this system, a pilot of the Royal Flying Corps, the forerunner to the Royal Air Force (RAF), was able to correct the fall of shot of the artillery by passing to the artillery battery commander details of how far from the target the guns were. The pilot would correct the shooting of the artillery by pointing out how far away and in what direction the shells of the guns had landed. The distance would be passed on using numbers and the direction using the picture of a clock face. The target was placed in the middle of the clock face and shells that fell beyond the target and on a straight line to the target would be corrected with a call of twelve, if it fell short on the same line the call would be six, at ninety degrees left of the target nine and ninety degrees right three. Any other direction would be corrected by using the hour on the clock with which it corresponded. This system would prove to function perfectly well throughout the whole of the First World War and was the system with which the RAF went to war in 1939.

The system of correcting artillery fire remained unchanged until 1938. The Air Council were against making alterations to the clock code system as they felt that it was adequate to meet the needs that the army would face in future conflicts. They felt that light aircraft could not be kept in action close to artillery units, as had been the case in the First World War.[4] The Air Council were also fearful of introducing a new, untried, and unfamiliar system with the growing tensions in Europe at this time. The War Office was unimpressed with the Air Councils attitude and pushed for more to be done. The Air Ministry agreed to trials between the Air Officer Commanding No. 22 (Army Co-operation) Group and the Commandant of the School of Artillery in December 1938.[5] The results of these trials and further trials conducted to test aircraft as well as procedure. The results were that light aircraft over the battlefield could observe fire with the ‘clock code’ system.[6] Spitfires conducted mock attacks on the aircraft and the Taylorcraft light aircraft observing the artillery fire had a good chance of dodging the fire of a modern fighter.[7] There was, however, no training for pilots in registering targets for the artillery. If an artillery officer required an appraisal of a prospective target, the request would have to be sent along the command chain via an air liaison officer. When the artillery battery received the information, it was usually out of date.[8] There was also pressure from within the War Office to establish a Flying Observation Post (Flying OP) and to begin plans to train Gunner Officers to fly. A Flying OP was to work in conjunction with Ground Observation Post (Ground OP) in establishing targets to be engaged and operating deep behind their lines to be afforded the protection of friendly anti-aircraft guns.

H 27983
A Taylorcraft Auster Mark III of No. 655 Squadron dropping a message bag to a Royal Artillery wireless truck on the airfield at Fowlmere, Cambridgeshire, during Exercise SPARTAN. (Source:  © IWM (H 27983))

The first of these Flying OPs was established in February 1940.[9] This force was established to:

[d]etermine in the light of practical experience obtained under war conditions the possibilities and limitations of the Flying OP, the most suitable type of aircraft and the most suitable organization [sic].[10]

The tests were to be conducted in three parts. The first was an initial training period. The second a practical training with the French, and a final test in the French Army area in conditions of actual warfare including shoots against German targets it was at this time that the term Air Observation Post (Air OP) was adopted.[11] The flight was sent to France on 19 April 1940.[12] The first of the three tests were conducted after the flight had moved to the continent. The final of the three tests was due to be carried out in early May, and the forces were established ready to conduct the tests on 9 May 1940.[13] The following day the Germans began to implement Fall Gelb (Case Yellow): the invasion of France and the Low Countries.[14] The artillery designated for the tests were forced to move back to their formations leaving the Air OP Flight (D Flight) waiting for the campaign to stabilise when it was clear that this would not happen D Flight was recalled to England.[15]

One of the first official moves at changing artillery co-operation policy was a letter regarding the subject sent from the Director of Military Co-operation Air Commodore Victor Goddard to Barratt at Army Co-operation Command. In this letter, Goddard states that the Air Staff were against the formation of:

[s]pecial air units for artillery observation or reconnaissance, unless it can be clearly shown that there is an urgent requirement for such units which cannot be met by Army Co-operations squadrons.[16]

The School of Artillery recommended that a certain number of aircraft should specialise in artillery work and should be trained by the School of Artillery so that they had the same tactical knowledge and the same the understanding of gunnery as an artillery officer.[17] This was just one aspect of an idea by the School of Artillery to allow aircraft to have tactical control over the fire of artillery batteries. To facilitate this, the school further recommended that a multi-seater aircraft should be employed in this work to allow an artillery officer to conduct the shoot according to artillery methods without the need for the artillery officer learning to fly. Artillery officers were also to be seconded to army co-operation squadrons specifically for artillery work.[18] The co-operation between the School of Artillery and Army Co-operation Command is evident and is surprising given the general relations that existed between the army and RAF in the wake of the Battle of France and the fall out that it had caused between the two services.[19]

Barratt, in a letter to the Under-Secretary of State for Air, wrote that:

I consider that in order to get a true and undistorted picture of this problem, it is first desirable to set out the problem as the Army [sic] sees it, and to show in this picture what they conceive to be their requirements.[20]

Again the desire to see the problem from a view that would almost certainly be contradictory to the RAF shows that Barratt and his command were willing to adopt a different approach and attitude in co-operating with at least one part of the army. Barratt also voiced his concerns regarding the ability of the Air OP to operate in the face of enemy action. It was felt that ‘the Air OP must be entirely vulnerable to any enemy fighters which cares to shoot it down’.[21] Barratt’s concern over the safety of his pilots who may be conducting shoots using the Air OP system was to be a recurring issue in the development of artillery reconnaissance.

TR 242
Air Marshal Sir Arthur Barratt in battledress and flying gear beside a Hawker Hurricane. He often flew this aircraft when visiting airfields of RAF Army Co-operation Command, which he commanded at the time of this picture. (Source: © IWM (TR 242))

Barratt’s response to the trials was one of scepticism, and he considered ‘that body of experience gained in the late war and since has all pointed to the advantages of the ‘Clock Code’ system’.[22] Barratt’s belief in the ‘clock code’ system stemmed more from the fear of false conclusions being drawn from brief experiments than from any sense of conservatism about changing the system used for artillery reconnaissance.[23] This became a realisation when Barratt was forced to explain to the Under Secretary of State for Air about the lack of efficiency regarding artillery co-operation in Army Co-operation Squadrons. Barratt wrote that:

I feel that much of the falling off in efficiency in this part of the Army Co-operation Squadron task has been due to the propagation of rumour as to other and better methods than those shown in AP 1176.[24]

Further trials were conducted using the artillery method during April 1941, and the conclusions reached were similar to those seen previously. These were that the artillery methods of ranging by corrections to line and range are simpler, quicker, and more efficient than any method based on the ‘clock code’.

The failures of the ‘clock code’ system in France combined with further problems faced in the fighting in Libya led to a loss of confidence in the system in the army.[25] Barratt responded that the ‘clock code’ system was not at fault in these operations but that the aircraft employed in it were operating in the face of intense enemy opposition. He was concerned that the trials had been too few and were skewed in favour of a positive result by the School of Artillery.[26] While these concerns may be interpreted as merely blocking a new development that had been shown to work to preserve the autonomy of the RAF while conducting army co-operation work. The evidence of co-operation between Army Co-operation Command and the School of Artillery, shown above, leads more to the conclusion that Barratt felt that the procedure could not be successfully carried out, and wished to see more trials conducted before it would receive his approval.

The procedure for artillery reconnaissance first developed during the First World War was only suitable for the conditions of that war. The lack of fluidity and almost stable front lines allowed a system to develop, quickly, this system, however, was only suited to those conditions. This was very quickly discovered during the first major test of this procedure against the quicker and more mobile warfare of the German Wehrmacht in 1940. The attitudes of both the British Army and the RAF to co-operation during the inter-war period, in Britain at least, did little to improve the situation before the British Expeditionary Force was stationed in France. This left those charged with the responsibility of modifying the existing procedure with only the experience of the First World War to guide them and on which to base their expectations. Much co-operation between the School of Artillery and Nos. 70 and 71 Groups of Army Co-operation Command occurred, despite the general feeling of animosity still felt by both services in Britain.[27] This co-operation was the most that had been seen between the army and RAF since the formation of the RAF as an independent force in 1918. Barratt’s move to block the adoption of the new procedure that was being trialled during 1941 can be interpreted in several ways. His reasoning for doing so, however, appears to be that of confirming the results already achieved through more rigorous and testing trials to confirm the results. Through further testing at a higher level the procedure, as well as those responsible for carrying it out, would be exposed to more stress and so a greater degree of authenticity could be achieved. Trials of this nature would also confirm if the procedure could be implemented with ease by the majority of pilots whose responsibility would be increased from observing the fall of shot to conducting shoots, potentially in the face of enemy opposition. Barratt’s major concern with the new system appears to be its increased complexity, and he was rightly concerned after his experiences in France that pilots would be unable to conduct the shoot if they had to keep a lookout for enemy fighter activity continually.

Dr Matthew Powell is a Teaching Fellow at Portsmouth Business School at the Royal Air Force College, Cranwell. He holds a PhD in Modern History from the University of Birmingham. His thesis investigated the development of tactical air power in Britain during the Second World War through a study of the RAF’s Army Co-operation Command. His first book, based on the PhD, The Development of British Tactical Air Power, 1940-1943: A History of Army Co-operation Command was published in 2016 by Palgrave Macmillan. He has also published in Canadian Military History, Air Power Review and the British Journal for Military History. He is currently researching the relationship between the British aviation industry and the Air Ministry during the inter-war period. He can be found on Twitter at @tac_air_power.

Header Image: An Auster Mark IV of an Air Observation Post squadron undergoes servicing at its base after being damaged by anti-aircraft fire while flying over the 8th Army Front in northern Italy. (Source: © IWM (CNA 3341))

[1] A longer version of this article can be found in Canadian Military History, 23:1 (2014), pp. 71-88.

[2] Jonathan Bailey, ‘Deep Battle 1914-1941: The Birth of the Modern Style of War,’ Field Artillery Journal, (1998), pp. 21-7.

[3] Ralph Barker, A Brief History of the Royal Flying Corps in World War I (London: Constable & Co., 2002), p. 63.

[4] H.J. Parham and E.M.G. Belfield, Unarmed into Battle: The Story of the Air Observation Post, Second Edition (Chippenham: Picton Publishing, 1986), p.14.

[5] Ibid.

[6] Ibid.

[7] Ibid

[8] Darrell Knight, Artillery Flyers at War: A History of the 664, 665, and 666 ‘Air Observation Post’ Squadrons of the Royal Canadian Air Force (Bennington, VT: Merriam Press, 2010), p. 27.

[9] Parham and Belfield, Unarmed into Battle, p.15.

[10] Ibid.

[11] Ibid.

[12] Ibid., p.16.

[13] Ibid.

[14] Karl-Heinz Freiser, The Blitzkrieg Legend: The 1940 Campaign in the West (Annapolis, MD: Naval Institute Press, 2005), p. 79.

[15] Parham and Belfield, Unarmed into Battle, 16.

[16] The National Archives (TNA), AIR 39/47, Letter from Air Commodore Goddard, Director of Military Co-operation to Barratt regarding Artillery Co-operation Policy, 8 December 1940.

[17] Ibid.

[18] Ibid.

[19] For more information on the army’s reaction to the Battle of France, see: TNA, CAB 106/220, Bartholomew Committee Final Report.

[20] TNA, AIR 39/47, Letter from Barratt to Under-Secretary of State for Air regarding co-operation with the Royal Artillery, 29 January 1941.

[21] Ibid., Appendix A, 29 January 1941.

[22] Ibid., Letter from Headquarters Army Co-operation Command to Headquarters No. 70 Group, Artillery Reconnaissance Trials, 12 April 1941.

[23] Ibid.

[24] Ibid., Letter from Barratt to Under Secretary of State for Air, 14 April 1941.

[25] Ibid., Letter from CGS on Artillery Reconnaissance, 5 May 1941.

[26] Ibid., Letter from Barratt to Major-General Otto Lund, GHQ Home Forces, in response from letter from CGS on Artillery Reconnaissance, 10 May 1941.

[27] For example, see: David Ian Hall, Strategy for Victory: The Development of British Tactical Air Power, 1919-1943 (Westport, CT: Praeger, 2008), pp. 89-103.