Editing Close air support (section)

===World War II===
====''Luftwaffe''====
[[File:Bundesarchiv Bild 101I-646-5188-17, Flugzeuge Junkers Ju 87.jpg|thumb|A flight of Ju 87 D-5s over the [[Eastern Front (World War II)|Eastern Front]], winter 1943–44.]]
As a continental power intent on offensive operations, Germany could not ignore the need for aerial support of ground operations. Though the ''[[Luftwaffe]]'', like its counterparts, tended to focus on strategic bombing, it was unique in its willingness to commit forces to CAS. Unlike the Allies, the Germans were not able to develop powerful [[strategic bombing]] capabilities, which implied industrial developments they were forbidden to take according to the [[Treaty of Versailles]].<ref name="ifri">{{cite journal |url=https://www.ifri.org/sites/default/files/atoms/files/fs35bistenenbaum.pdf |title=The Battle over Fire Support: The CAS Challenge and the Future of Artillery |journal=Focus stratégique |volume=35 bis |date=October 2012 |last=Tenenbaum |first=Elie |publisher=Institut français des relations internationales |isbn=978-2-36567-083-8}}</ref> In joint exercises with [[Sweden]] in 1934, the Germans were first exposed to [[dive bomber|dive-bombing]], which permitted greater accuracy while making attack aircraft more difficult to track by antiaircraft gunners. As a result, [[Ernst Udet]], chief of the Luftwaffe's development, initiated procurement of close support dive bombers on the model of the U.S. Navy's [[SBC Helldiver|Curtiss Helldiver]], resulting in the [[Henschel Hs 123]], which was later replaced by the famous [[Junkers Ju 87]] ''Stuka''. Experience in the [[Spanish Civil War]] lead to the creation of five ground-attack groups in 1938,{{dubious|date=October 2011|German "ground-attack squadron" is normally understood as Schlachtgeschwader (mainly Henschel Hs 123 and Hs 129), while this text seems to describe Sturzkampfgeschwader ("dive-bombing squadron", mainly Ju 87).}} four of which would be equipped with ''Stukas''. The Luftwaffe matched its material acquisitions with advances in the air-ground coordination. General [[Wolfram von Richthofen]] organized a limited number of air liaison detachments that were attached to ground units of the main effort. These detachments existed to pass requests from the ground to the air, and receive reconnaissance reports, but they were not trained to guide aircraft onto targets.{{citation needed|date=September 2020}}

These preparations did not prove fruitful in the [[invasion of Poland]], where the Luftwaffe focused on interdiction and dedicated few assets to close air support. But the value of CAS was demonstrated at the crossing of the [[Meuse River]] during the [[Invasion of France (Nazi Germany)|Invasion of France]] in 1940. General [[Heinz Guderian]], one of the creators of the combined-arms tactical doctrine commonly known as "''[[blitzkrieg]]''", believed the best way to provide cover for the crossing would be a continuous stream of ground attack aircraft on French defenders. Though few guns were hit, the attacks kept the French under cover and prevented them from manning their guns. Aided by the sirens attached to ''Stukas'', the psychological impact was disproportional to the destructive power of close air support (although as often as not, the Stukas were used as [[tactical bomber]]s instead of close air support, leaving much of the actual work to the older Hs 123 units for the first years of the war). In addition, the reliance on air support over artillery reduced the demand for logistical support through the Ardennes. Though there were difficulties in coordinating air support with the rapid advance, the Germans demonstrated consistently superior CAS tactics to those of the British and French defenders. Later, on the [[Eastern Front (World War II)|Eastern front]], the Germans would devise visual ground signals to mark friendly units and to indicate direction and distance to enemy emplacements.{{citation needed|date=September 2020}}

Despite these accomplishments, German CAS was not perfect and suffered from the same misunderstanding and [[interservice rivalry]] that plagued other nations' air arms, and friendly fire was not uncommon. For example, on the eve of the Meuse offensive, Guderian's superior cancelled his CAS plans and called for high-altitude strikes from medium bombers, which would have required halting the offensive until the air strikes were complete. Fortunately for the Germans, his order was issued too late to be implemented, and the Luftwaffe commander followed the schedule he had previously worked out with Guderian.{{citation needed|date=July 2012}} As late as November 1941, the Luftwaffe refused to provide [[Erwin Rommel]] with an air liaison officer for the ''[[Afrika Korps]]'', because it "would be against the best use of the air force as a whole."<ref name=House2001/>{{page needed|date=July 2012}}

German CAS was also extensively used on the [[Eastern Front (World War II)|Eastern Front]] during the period 1941–1943. Their decline was caused by the growing strength of the Red Air Force and the redeployment of assets to defend against American and British strategic bombardment. Luftwaffe's loss of air superiority, combined with a declining supply of aircraft and fuel, crippled their ability to provide effective CAS on the western front after 1943.{{citation needed|date=July 2012}}

====RAF and USAAF====
[[File:Douglas SBD Dauntless dropping a bomb, circa in 1942.jpg|thumb|right|[[United States Navy|U.S. Navy]] [[Douglas SBD Dauntless|SBD Dauntless]] dropping its bomb]]
The [[Royal Air Force]] (RAF) entered the war woefully unprepared to provide CAS. In 1940 during the [[Battle of France]], the Royal Air Force and Army headquarters in France were located at separate positions, resulting in unreliable communications. After the RAF was withdrawn in May, Army officers had to telephone the [[War Office]] in London to arrange for air support. The stunning effectiveness of German air-ground coordination spurred change. On the basis of tests in [[Northern Ireland]] in August 1940, [[Group Captain]] A. H. Wann RAF and Colonel J.D. Woodall (British Army) issued the Wann-Woodall Report, recommending the creation of a distinct tactical air force liaison officer (known colloquially as "tentacles") to accompany Army divisions and brigades. Their report spurred the RAF to create an [[RAF Army Cooperation Command]] and to develop tentacle equipment and procedures placing an Air Liaison Officer with each brigade.<ref>Delve 1994, p. 100.</ref>

Although the RAF was working on its CAS doctrine in London, officers in North Africa improvised their own coordination techniques. In October 1941, [[Arthur Tedder, 1st Baron Tedder|Sir Arthur Tedder]] and [[Arthur Coningham (RAF officer)|Arthur Coningham]], senior RAF commanders in North Africa, created joint RAF-Army Air Support Control staffs at each corps and armored division headquarters, and placed a Forward Air Support Link at each brigade to forward air support requests. When trained tentacle teams arrived in 1942, they cut response time on support requests to thirty minutes.<ref name=House2001 />{{page needed|date=July 2012}} It was also in the North Africa desert that the [[cab rank (disambiguation)|cab rank]] strategy was developed.<ref>{{cite book |title=Strike from Above: The History of Battlefield Air Attack 1911–1945|pages=181–182 }}</ref> It used a series of three aircraft, each in turn directed by the pertinent ground control by radio. One aircraft would be attacking, another in flight to the battle area, while a third was being refuelled and rearmed at its base. If the first attack failed to destroy the tactical target, the aircraft in flight would be directed to continue the attack. The first aircraft would land for its own refuelling and rearming once the third had taken off.{{citation needed|date=May 2009}} The CAS tactics developed and refined by the British during the [[North Africa Campaign|campaign in North Africa]] served as the basis for the Allied system used to subsequently gain victory in the air over Germany in 1944 and devastate its cities and industries.<ref name="Hallion" />

The use of [[forward air control]] to guide close air support (CAS)<ref>{{cite web|url=http://www.mod.uk/NR/rdonlyres/4463968B-8061-4E75-BDC3-05074EFA8AFF/0/20071218_ijwp3_30_U_DCDCIMAPPS.pdf |title=Joint Air Operations Interim Joint warfare Publication 3–30 |pages=4–5 |publisher=MoD |quote=CAS in defined as air action against targets that are in proximity to friendly forces and require detailed integration of each air mission with the fire and movement of these forces |url-status=dead |archive-url=https://web.archive.org/web/20110608001520/http://www.mod.uk/NR/rdonlyres/4463968B-8061-4E75-BDC3-05074EFA8AFF/0/20071218_ijwp3_30_U_DCDCIMAPPS.pdf |archive-date=2011-06-08 }}</ref> aircraft, so as to ensure that their attack hits the intended target and not friendly troops, was first used by the British [[Desert Air Force]] in North Africa, but not by the USAAF until operations in Salerno.<ref>{{cite web|url=https://apps.dtic.mil/sti/pdfs/ADA466970.pdf|archive-url=https://web.archive.org/web/20110604194605/http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA466970&Location=U2&doc=GetTRDoc.pdf|url-status=live|archive-date=June 4, 2011|title=The Twelfth US Air Force Tactical and Operational Innovations in the Mediterranean Theater of Operations, 1943–1944.|author=Matthew G. St. Clair |quote=The use of forward air controllers (FAC) was another innovative technique employed during Operation Avalanche. FACs were first employed in the Mediterranean by the British Desert Air Force in North Africa but not by the AAF until operations in Salerno. This type of C2 was referred to as 'Rover Joe' by the United States and 'Rover David' or 'Rover Paddy' by the British.|publisher=Air University Press Maxwell Air Force Base, Alabama |date=February 2007}}</ref> During the [[North African Campaign]] in 1941 the [[British Army]] and the [[Royal Air Force]] established Forward Air Support Links (FASL), a mobile air support system using ground vehicles. Light reconnaissance aircraft would observe enemy activity and report it by radio to the FASL which was attached at brigade level. The FASL was in communication (a two-way radio link known as a "tentacle") with the Air Support Control (ASC) Headquarters attached to the corps or armoured division which could summon support through a Rear Air Support Link with the airfields.<ref>Ian Gooderson, ''Air power at the Battlefront: Allied Close Air Support in Europe, 1943–45'', p. 26</ref><ref>{{cite news|url=http://findarticles.com/p/articles/mi_hb3101/is_4_53/ai_n29316931/|title=Forward air control: a Royal Australian Air Force innovation |work=Air Power History |first=Carl A. |last=Post |year=2006}}</ref> They also introduced the system of ground direction of air strikes by what was originally termed a "Mobile Fighter Controller" traveling with the forward troops. The controller rode in the "leading tank or armoured car" and directed a "cab rank" of aircraft above the battlefield.<ref>{{cite web |work=Short History of the Royal Air Force |url=http://www.raf.mod.uk/rafcms/mediafiles/F21D57C4_9913_5321_BB9830F0BB762B4E.pdf |publisher=RAF |title=RAF & Army Co-operation |page=147 |url-status=dead |archive-url=https://web.archive.org/web/20110806021956/http://www.raf.mod.uk/rafcms/mediafiles/F21D57C4_9913_5321_BB9830F0BB762B4E.pdf |archive-date=2011-08-06 }}</ref> This system of close co-operation first used by the Desert Air Force, was steadily refined and perfected, during the campaigns in Italy, Normandy and Germany.

[[File:Mobile Fighter Controllers.jpg|thumb|right|British Mobile Fighter Controllers providing [[forward air control]] during World War II]]

By the time the [[Italian Campaign (World War II)|Italian Campaign]] had reached [[Rome]], the Allies had established [[air superiority]]. They were then able to pre-schedule strikes by [[fighter-bomber]] squadrons; however, by the time the aircraft arrived in the strike area, oftentimes the targets, which were usually trucks, had fled.<ref name="Strikefrom">{{Cite book|last=Hallion, Richard. P|url=https://www.worldcat.org/oclc/19590167|title=Strike from the sky: the history of battlefield air attack, 1911–1945|date=1989|publisher=Smithsonian Institution Press|isbn=0-87474-452-0|location=Washington|pages=181–182|oclc=19590167}}</ref> The initial solution to fleeing targets was the British "Rover" system. These were pairings of air controllers and army liaison officers at the front but able to switch communications seamlessly from one brigade to another – hence Rover. Incoming strike aircraft arrived with pre-briefed targets, which they would strike 20 minutes after arriving on station only if the Rovers had not directed them to another more pressing target. Rovers might call on artillery to mark targets with smoke shells, or they might direct the fighters to map grid coordinates, or they might resort to a description of prominent terrain features as guidance. However, one drawback for the Rovers was the constant rotation of pilots, who were there for fortnightly stints, leading to a lack of institutional memory. US commanders, impressed by the British tactics at the Salerno landings, adapted their own doctrine to include many features of the British system.<ref>{{cite web|url=http://www.fac-assoc.org/Ancestry/ancestryofforwardaircontrollersthroughtwwii.htm |title=The Ancestry of Forward Air Controllers |quote=fundamental feature of the system was use of waves of strike aircraft, with pre-briefed assigned targets but required to orbit near the line of battle for 20 minutes, subject to Rover preemption and use against fleeting targets of higher priority or urgency. If the Rovers did not direct the fighter-bombers, the latter attacked their pre-briefed targets. US commanders, impressed by British at the [[Salerno landings]], adapted their own doctrine to include many features of the British system, leading to differentiation of British 'Rover David', US 'Rover Joe' and British 'Rover Frank' controls, the last applying air strikes against fleeting German artillery targets. |author=Charles Pocock |publisher=Forward Air Controllers Association |url-status=dead |archive-url=https://web.archive.org/web/20130825064743/http://www.fac-assoc.org/Ancestry/ancestryofforwardaircontrollersthroughtwwii.htm |archive-date=August 25, 2013 }}</ref>

At the start of the War, the [[United States Army Air Forces]] (USAAF) had, as its principal mission, the doctrine of strategic bombing. This incorporated the unerring belief that unescorted bombers could win the war without the advent of ground troops. This doctrine proved to be fundamentally flawed. However, during the entire course of the war the USAAF top brass clung to this doctrine, and hence operated independently of the rest of the Army. Thus it was initially unprepared to provide CAS, and in fact, had to be dragged "kicking and screaming" into the CAS function with the ground troops. USAAF doctrinal priorities for tactical aviation were, in order, air superiority, isolation of the battlefield via supply interdiction, and thirdly, close air support. Hence, during the [[North African Campaign]], CAS was poorly executed, if at all. So few aerial assets were assigned to U.S. troops that they fired on anything in the air. And in 1943, the USAAF changed their radios to a frequency incompatible with ground radios.{{citation needed|date=September 2020}}

The situation improved during the [[Italian Campaign (World War II)|Italian Campaign]], where American and British forces, working in close cooperation, exchanged CAS techniques and ideas. There, the AAF's XII Air Support Command and the Fifth U.S. Army shared headquarters, meeting every evening to plan strikes and devising a network of liaisons and radios for communications. However, friendly fire continued to be a concern – pilots did not know recognition signals and regularly bombed friendly units, until an A-36 was shot down in self-defense by Allied tanks.{{citation needed|date=September 2020}} The expectation of losses to friendly fire from the ground during the planned invasion of France prompted the black and white [[invasion stripes]] painted on all Allied aircraft from 1944.<ref>{{cite web |url=https://airandspace.si.edu/stories/editorial/stripes-d-day |title=The Stripes of D-Day |first=Allan  |last=Janus |website=[[National Air and Space Museum]] |date=6 June 2014 |access-date=20 November 2016}}</ref><ref>{{cite web |url=http://paul.rutgers.edu/~mcgrew/wwii/usaf/html/DDay.html |title=Army Air Forces and the Normandy Invasion, April 1 to July 12, 1944 |first=Frederick J. |last=Shaw |work=U.S. Air Force |via=Rutgers University |access-date=September 12, 2020 |archive-date=August 31, 2019 |archive-url=https://web.archive.org/web/20190831114958/http://paul.rutgers.edu/~mcgrew/wwii/usaf/html/DDay.html |url-status=dead }}</ref>

In 1944, USAAF commander Lt. Gen. [[Henry H. Arnold|Henry ("Hap") Arnold]] acquired 2 groups of [[SBD Dauntless|A-24]] dive bombers, the army version of the Navy's SBD-2, in response to the success of the ''Stuka'' and German CAS. Later, the USAAF developed a modification of the [[North American P-51 Mustang]] with dive brakes – the [[North American A-36 Apache]]. However, there was no training to match the purchases. Though Gen. Lesley McNair, commander of Army Ground Forces, pushed to change USAAF priorities, the latter failed to provide aircraft for even major training exercises. Six months before the [[invasion of Normandy]], 33 divisions had received no joint air-ground training.{{citation needed|date=September 2020}}
[[File:013754 09 Strafing at Gona Buna.JPG|left|thumb|A [[United States Navy|U.S. Navy]] aircraft [[strafing]] Japanese positions during the [[New Guinea campaign]] of the [[Pacific War]], 1942]]
The USAAF saw the greatest innovations in 1944 under General [[Elwood Quesada]], commander of IX Tactical Air Command, supporting the First U.S. Army. He developed the "armored column cover", where on-call fighter-bombers maintained a high level of availability for important tank advances, allowing armor units to maintain a high tempo of exploitation even when they outran their artillery assets. He also used a modified antiaircraft radar to track friendly attack aircraft to redirect them as necessary, and experimented with assigning fighter pilots to tours as forward air controllers to familiarize them with the ground perspective. In July 1944, Quesada provided VHF aircraft radios to tank crews in Normandy. When the armored units broke out of the Normandy beachhead, tank commanders were able to communicate directly with overhead fighter-bombers. However, despite the innovation, Quesada focused his aircraft on CAS only for major offensives. Typically, both British and American attack aircraft were tasked primarily to interdiction, even though later analysis showed them to be twice as dangerous as CAS.{{citation needed|date=September 2020}}

[[XIX Tactical Air Command|XIX TAC]], under the command of General [[Otto P. Weyland]] used similar tactics to support the rapid armored advance of [[General Patton]]'s Third Army in its drive across France. Armed reconnaissance was a major feature of XIX TAC close air support, as the rapid advance left Patton's Southern flank open. Such was the close nature of cooperation between the Third Army and XIX TAC that Patton actually counted on XIX TAC to guard his flanks. This close air support from XIX TAC was credited by Patton as having been a key factor in the rapid advance and success of his Third Army.<ref>Spires 2002. {{page needed|date=September 2020}}</ref>

The American Navy and Marine Corps used CAS in conjunction with or as a substitute for the lack of available artillery or naval gunfire in the [[Pacific Ocean theater of World War II|Pacific theater]]. Navy and Marine [[F6F Hellcat]]s and [[F4U Corsair]]s used a variety of [[Aircraft ordnance|ordnance]] such as conventional bombs, rockets and napalm to dislodge or attack Japanese troops using cave complexes in the latter part of the Second World War.<ref name="Barber2">Barber 1946, [https://web.archive.org/web/19980703132559/http://www.history.navy.mil/download/nasc.pdf Table 2].</ref><ref>[https://warfarehistorynetwork.com/daily/wwii/whistling-death-the-chance-vought-f4u-corsair/ "Whistling Death: The Chance-Vought F4U Corsair"] {{Webarchive|url=https://web.archive.org/web/20190625034438/https://warfarehistorynetwork.com/daily/wwii/whistling-death-the-chance-vought-f4u-corsair/ |date=2019-06-25 }}. ''Warfare History Network''. 16 December 2018.</ref>

====Red Air Force====
The [[Soviet Union]]'s [[Red Air Force]] quickly recognized the value of ground-support aircraft. As early as the [[Battle of Khalkhin Gol|Battles of Khalkhyn Gol]] in 1939, Soviet aircraft had the task of disrupting enemy ground operations.<ref>Coox 1985, p. 663.</ref> This use increased markedly after the June 1941 [[Operation Barbarossa|Axis invasion of the Soviet Union]].<ref>Austerslått, Tor Willy. [http://break-left.org/air/il-2.html "Ilyushin Il-2"]. {{Webarchive|url=https://web.archive.org/web/20110515195955/http://break-left.org/air/il-2.html |date=15 May 2011 }} ''break-left.org'', 2003. Retrieved: 27 March 2010.</ref> Purpose-built aircraft such as the [[Ilyushin Il-2]] ''Sturmovik'' proved highly effective in blunting the activity of the ''[[Panzer]]s''. [[Joseph Stalin]] paid the Il-2 a great tribute in his own inimitable manner: when a particular production factory fell behind on its deliveries, Stalin sent the following cable to the factory manager: "They are as essential to the [[Red Army]] as air and bread".<ref name="stalinquote"/>