CHAPTER TWO: THE SYSTEM
The first fruit of Churchill's October 1942 ruling on tactical air forces came in North Africa, with the RAF elements operating there becoming known as the Desert Air Force or "DAF". This is generally considered the first practical expression of the tactical air force idea. Meanwhile, back in Britian planning was underway for "OVERLORD", the cross-channel invasion of the continent. On 1 June 1943, the "2nd Tactical Air Force" formally came into being.
Between June 1943 and June 1944 2nd TAF grew, eventually becoming a huge organization. With some 2000 aircraft, by D-Day it numbered almost a hundred squadrons divided between four Groups and one strategic reconaisance wing, plus considerable control and support elements.
The doctrinal and bureaucratic wars of the preceding years had resulted in the general principle known as the system of "joint command".Under this system, headquarters were paired at each level of command. Second TAF itself was in support of Montgomery's 21st Army Group, and both of these formations had a headquarters which were deemed to be co-equal. At the next level down, 83 and 84 Group were to be in support of Second British and First Canadian Armies respectively.
This meant that contrary to the Army's wishes, at no level could Army commanders order air support. Air forces were never under the command of Army commanders. Both services remained under their own, completely seperate, chains of command. In fact, the lowest level at which the two chains of command met, was in the person of the Supreme Commander himself, General Eisenhower. This would remain a contentious issue between the two services.
As mentioned earlier, of crucial importance to the system devised to control air power was a special radio network soley dedicated to passing air support requests. To do this, new organizations known as "Air Support Signals Units" or ASSUs were created. These were Army units, of some 225 men from the Royal Signals Corps, and they provided the radio links to tie all of the various parts of each composite group together.
The parts were many and complex. As we have seen, each Army headquarters (1st Canadian and 2nd British) was paired with a Composite Group headquarters (84 and 83 Groups respectively). Just as headquarters 2nd TAF normally co-located with headquarters 21st Army Group, so the Army and Composite Group headquarters normally co-located. This was the level -- Composite Group/Army headquarters level -- at which joint army/air force consulation was performed to prioritize missions and issue direction.
Each of the Composite Groups also had an organization known as a Group Control Centre or GCC. This was the air organization that actually directed and controlled the flying aircraft. The GCC would scramble planes, and vector them to their targets, just as the static Sector Headquarters had so famously done during the Battle of Britain. The GCC was in communication with and exercised control over all aircraft flying within its sector. Since this was a purely air function, the GCC was not normally co-located with either the Group or Army headquarters.
With the forward troops there were various "tentacles" as they were called, apparently since this was what they so resembled on the radio network organization charts. These tentacles were small vehicle mounted teams with an army officer trained in air support and a small team of signallers and radios. The Army officers who performed this function were known as Air Liaison Officers, or "ALOs." The ALO commanding a tentacle would liaise with the local ground commander and advise upon the application of airpower. He would also pass requests for air support directly back to the joint Army/GCC headquarters, over the ASSU radio net. Forward tentacles were not, however, in radio communication with any aircraft.
This was the system that had grown out of the Wann/Woodall report and experience in North Africa and Italy. Its sailient feature being the ASSU radio network to allow the passage of forward requests for air support directly back to the controlling authority, without going through the whole intermediate chain-of-command.
Specialized tentacles were also developed over time, including VCPs (Visual Control Posts), FCPs (Forward Control Posts) and contact cars.
ASSU tentacle. Standard ASSU tentacles consisted of a small team with Army type radio sets, normally mounted in a White Scout car. The primary task of a normal tentacle was to pass air requests from the forward troops directly back to the joint Army/Composite Group headquarters via the ASSU net. Standard tentacles did not have any Air Force personnel and could not communicate with aircraft.
FCP. Each Army/Composite Group had one Forward Control Post or FCP. The intent was to form a special team which could focus air power even more quickly and closely on a critical sector of the front than the normal control procedure provided for. FCPs were much larger than normal tentacles. The FCP's radio sets allowed it to both listen in on the ground-based ASSU nets and to speak with aircraft overhead by VHF radio.
VCP. Visual Control Posts or VCPs were a new inovation introduced part way through the Normandy campaign. They were essentially a normal tentacle augmented with a pilot and VHF radio for communication with overhead aircraft. The intent was for the RAF pilot to "talk" the strike pilots onto the target "using the language one pilot would use to another."
Contact Car. A contact car was very similar to a normal tentacle, but it was not an ASSU unit, and it was manned by RAF rather than Army personnel. It also included a pilot, normally a reconaisance pilot, and a VHF radio that could contact aircraft overhead. Although contact cars could communicate with overhead aircraft and thus had the technical means to direct airstrikes directly, this was not the intent. Contact cars were meant to facilitate liaison between reconaisance aircraft and lead Army elements, rather than to actually direct airstrikes.
The actual flying squadrons of the Composite Groups were located at airfields as close to the front as possible. In fact, each Composite Group had an organic unit of engineering troops specifically for the purpose of building air fields just behind the advancing armies. Typically, one or two wings of three or four squadrons each would be based at a single airfield. ALOs from the Army, were posted to each airfield. There, they would monitor front-line developments on the ASSU radio network and through Army channels, in order to provide briefings to the pilots on the ground situation before they took off on missions. Finally, 2nd TAF had a considerable service support tail, consisting of everything from a field hospital for wounded Air Force personnel to "Ground Servicing Units" for aircraft damaged beyond the ability of the forward airfields' own repair capabilities.
By 1944, British doctrine for army/air operations specified that the RAF would contribute to the land battle in five principal ways:
Of these five roles, 2nd TAF was primarily concerned with air superiority and the attack of ground targets, and to a lesser extent reconnaissance.
This led to a wide variety of mission types for 2nd TAF. As the above list suggests, 2nd TAF very much saw its first responsibility as the classic fighter role of maintaining air superiority. Defensive patrols were flown, particularly over the vulnerable shipping lanes and invasion beaches. The pre-ponderance of such defensive missions fell off throughout the campaign as it became clear how secure Allied air supremacy was.
When it came to the actual attack of ground targets contemporary British doctrine distinguished between "indirect support" and "direct support."
Direct support was further categorized on the basis of urgency, distinction being made between "pre-arranged" and "impromptu" requests for air support. Pre-arranged attacks were planned through the dedicated staff process, sometimes weeks ahead of time, but routinely for the next day. Impromptu requests were originated in the heat of battle by leading Army headquarters and forwarded via the special ASSU radio networks for the dispatch of aircraft as quickly as possible.
Pre-arranged air support
The centre of the process for planning pre-arranged air support was the Air Conference at Army/Group headquarters, which was meant to be held every evening but in practice it usually only met approximately every other day. These were quite a large affairs, often attended by some 20 staff officers and chaired by the Army headquarters Chief of Staff. This conference would discuss the situation and routine operations for the next day. After the conference direction for the flying wings for the next day would be issued by the Group headquarters. Additionally, specific conferences would be called for planning major operations as necessary.
Impromptu Request Procedure
Since all of these elements were tied together on a single net by the radio communications of the ASSU, information could be passed about quickly. The intent was to allow the tentacles, often forward with brigade or even battalion headquarters, to pass air requests directly back to Group/Army headquarters, without passing through the intermediate divisional and corps levels of command. The Army/Composite Group joint air staff could then either authorize or deny the request. The GCC meanwhile, which was also listening in on the same net, would be concurrently ensuring that the necessary aircraft were ready. Thus, immediately upon the request being authorized, aircraft could be dispatched.
More Detailed Explanation of the Standard Procedure for air support.
If an FCP or VCP was forward in the target area, it could shorten the authorization process and improve the communications between the ground formations and the aircraft overhead. RAF pilots with the FCP or VCP would establish communications with the strike aircraft and brief their pilots on the mission over the radio.
More Detailed Explanation of the Procedure with FCP or VCP for air support.
Aside from air strikes sent out to strike specific point targets, there were also two other important mission types within the tactical air power system: what were known as "CABRANKs" and "Armed Reconnaissances".
CABRANK. This was perhaps the most famous means of providing air support. A package of fighter-bombers would be kept circling just behind the front. There, they would be immediately available to swoop down upon a target as soon as a forward tentacle called for support. If the ground troops were advancing, the CABRANK could advance with them. The somewhat whimsical name CABRANK presumably arose because of circling aircrafts' resemblance to a rank of cabs waiting for customers in front of a London club or hotel.
Armed Recce. Armed reconaisance, or "armed recce" as it was commonly known, was a mission type in which a group of fighter-bombers were given a route or area behind German lines to patrol. They would then range over this area, collecting valueable intelligence and attacking any targets of opportunity, with either bombs, rockets or straffing. This was the mission type that led to so many shot-up German columns on the Norman roads, and it came to be perhaps the most important mission type of the campaign.
General Remarks on the System
Air attacks were thus either "direct" or "indirect", with direct being further sub-divided into "pre-arranged" and "impromptu".
However, pre-arranged and impromptu were not entirely distinct. The CABRANK system was the primary means of bridging the gap between pre-arranged and impromptu air support. CABRANK amounted to a planned allocation of aircraft to be waiting for targets of opportunity. Similarly, a certain portion of 2nd TAF's assets were routinely left unallocated, so as to be available for immediate scrambling in response to impromptu requests.
The lead time for air support thus varied from plans drawn up days or even weeks ahead of time, to routine requests for air support the next day. The timeliness of response to impromptu requests varied as well. By some accounts, impromptu requests, if filled from within the Composite Group's own squadrons by a standard tentacle, averaged about an hour from the application for an air strike to the appearance of the aircraft on target. By other accounts, it could take several hours, unless an FCP or VCP was present. At the other extreme, if there was a CABRANK directly available, aircraft could be diverted onto the target even more quickly, sometimes literally within minutes.