Although Alconbury is best known as a major Cold War airfield, it had humble origins and was first brought into use in 1938 as a scatter field for the new bomber station at Upwood. It had been recognised that the new bomber bases would inevitably be targetted by the enemy and it became a matter of priority to find suitable sites for dispersing aircraft away from the parent station. Alconbury became one of the very first to be brought into use, when it was temporarily occupied on a trial basis by the Fairey Battles of 63 Squadron in May 1938.
With the outbreak of war in the following year, Upwood was given a training roll and responsibility for Alconbury changed to the nearby operational bomber station at Wyton. The Battles and Ansons of 52 Squadron then vacated Alconbury, which at the time, consisted merely of a 150 acre grass field. Occupying Wyton were two Blenheim light bomber squadrons (114 and 139) and it was an aircraft from one of these (N6215) of 139 Squadron which flew the very first RAF mission of WW2. The purpose of this was to photograph German warships leaving their base at Wilhelmshaven. Since air attacks on British airfields were expected at any time, the two Wyton squadrons took turns in dispersing their Blenheims at Alconbury for two or three weeks at a time. Conditions were muddy, crude and uncomfortable and as autumn 1939 gave way to the fierce winter months of 1940, the scatter field was used less and less.
In the meantime, 114 and 139 Squadrons had been replaced at the parent station by 15 and 40 Squadrons and like their predecessors, were equipped with Blenheims. From 14 April, 15 Squadron had to suffer the inconvenience of having all its aircraft outbased at Alconbury and since the satellite (now reclassified from scatter airfield) had virtually no accommodation, crews were in constant transit between one place and the other. For operations, the Blenheims had to be bombed up at Wyton and were also despatched from the parent station.
With the commencement of the 'Blitzkreig' on 10 May 1940, every effort was made to stem the enemy advance and a disaster overtook 15 Squadron on 12 May 1940, when of twelve aircraft sent to attack bridges at Maastricht, only six returned. Three days later the squadron returned to Wyton, but continued to use Alconbury on an occasional basis. On 19 June 1940, for example, 15 Squadron was returning in the moonlight from a raid on Boos and landed at the satellite in order to avoid attracting attention to Wyton by lighting up a flare path there.
Development of the Airfield
It soon became clear that satellite airfields would be of far greater use if they were given sufficient basic facilities to house and operate a squadron of their own, leaving all maintenance and administrative work to be done at the parent station. Between June and October 1940 therefore, flying ceased at Alconbury whilst three hard runways were built, together with basic hutted accommodation for the crews. The work being done obviously attracted the attention of the Luftwaffe as the landing ground was attacked by enemy bombers on 16 September 1940, although no serious damage was done.
By early October, the work was sufficiently advanced for aircraft to return and the first to arrive were the Blenheims of 'B' Flight 40 Squadron. Within a month, this unit began to convert on to Vickers Wellingtons and from December 1940 onwards these much heavier aircraft were being bombed up and despatched from Alconbury on operations over Germany. At the same time 15 Squadron over at Wyton was also re-equipped with Wellingtons but since the all-grass airfield there was often unserviceable in the wet winter weather, this unit's aircraft also took advantage of the new runways at the satellite. Although they were often bombed up and despatched from here during this period, they usually landed back in their unloaded state at Wyton.
It was because of the hopeless waterlogging of another nearby bomber base at Oakington in early 1941, that Alconbury was first involved in airborne photo reconnaissance. At the time, RAF Bomber Command had its own unit for this purpose, designated 3 Photo Reconnaissance Unit. This unit was equipped with specially modified Spitfires and its task was to assess the damage caused by bombing raids on enemy territory. For many weeks in early 1941 ground conditions at Oakington were so bad that the Spitfires used Alconbury as their regular operating base for their all important photographic sorties.
Operational Build Up
From February 1941, when sufficient accommodation had been completed, the whole of 40 Squadron moved in to stay on a regular basis. For the next eight months the squadron's Wellingtons were increasingly involved in Bomber Command's main force raids, not only on industrial targets in Germany but also on the German navy in the ports on the Atlantic coast of France. One notable operation in which they took part was the large raid flown on 24 July against Brest, where some of the principal German battleships were undergoing repairs in preparation for a new campaign against British shipping.
This was the time of the Blitz, when many parts of Britain were being subjected to an almost nightly series of heavy air raids. On two nights, 8 March and 11 June, the airfield at Alconbury was again bombed and on both of these occasions one Wellington was damaged on the ground.
Operations were unaffected, although the number of aircraft despatched on any one raid was very modest compared with what would come later. A 'maximum effort' on the night of 12/13 October 1941, for example, saw 12 Wellingtons sent off to attack Germany, nine to Nuremberg and three to Bremen. Losses were all too frequent and two aircraft (X9822 and Z9926) failed to return that night.
Further Extensions and Heavy Bombers
Meanwhile plans were drawn up for extensions to all three of the original runways. As built the main NE/SW runway was 1600yds long, whilst the two subsidiaries were only 1100yds each. Bomber Command's experience with the first of the four engined heavy bombers, such as the Halifax and Stirling, had made it all to clear that such dimensions were inadequate. A new standard was therefore set which was to last for the rest of the war, one main runway of 2000yds and two subsidiaries of 1400yds each. The proximity of the main trunk road along the southern boundary of the airfield made it necessary to undertake the lengthening work elsewhere and the biggest extension stretched north eastwards towards the East Coast main railway line.
Elsewhere in the world, hostilities were becoming more and more demanding in mid-1941, notably in the Middle East. It was essential to strengthen the RAF bomber force in the Mediterranean and for this a major contribution was made by 40 Squadron, which sent two of its three flights of Wellingtons to Malta in October. Operations from Alconbury were continued on a smaller scale but the spare capacity now available was soon taken up by 15 Squadron, which moved in for six months whilst Wyton was closed for runway construction. Since it had been based here previously, 15 Squadron had been re-equipped with Stirlings and these massive heavy bombers immediately dominated the local scene.
As well as attacking industrial targets in Germany, the Stirlings were also detached to Lossiemouth in January for attacks on enemy warships, whilst on 12 February 1942 they were despatched from Alconbury to attack the 'Scharnhorst' and 'Gneisenau' as they made their notorious dash up the English Channel. More conventional targets in March and April 1942 were Essen, Lubeck and Cologne whilst the Stirlings also took part in airborne minelaying operations off the enemy coast.
Meanwhile it was decided in February that 40 Squadron should be concentrated in the Middle East whereupon that part of the squadron remaining at Alconbury should be used as a nucleus for the formation of a completely new Wellington unit, 156 Squadron. This was soon operating at full strength and in May 1942 made a full-scale contribution to all three of the 'Thousand Bomber Raids' mounted against Germany at this time, successively despatching 16, 14 and 20 aircraft on the raids against Cologne, Essen and Bremen.
The Major Changes of 1942
August 1942 was to see major changes on the airfields in the area, many of which would henceforth be used to house the squadrons designated to form the new Pathfinder Force, which was centred on Wyton. One of these was 156, which was transferred to Warboys to undertake its new target marking role. It had originally intended use Alconbury as a Pathfinder station and to house here the critically important Pathfinder Navigation Training Unit, but this was overtaken by the developments outlined below.
The most notable change of all was the arrival in Britain of the first flying units of the USAAF. Whilst airfields were then under construction all over eastern England there was a cluster of new bases, either recently opened or nearly completed, in Huntingdonshire and the adjacent counties. These included Polebrook, Grafton Underwood, Kimbolton, Molesworth and Chelveston, so together with Alconbury, which happened to be in the same general area, these were the very first to be allocated for use by the incoming American units.
The Arrival of the USAAF.
The Americans began to move into Alconbury at the end of August 1942 and in early September the station became the temporary home of the 93rd Bombardment Group. It must have been quite a culture shock for the new arrivals, since Alconbury looked much more like a building site at that time than an operational airfield. The accommodation had now been considerably expanded but consisted solely of wartime austerity hutting, whilst the airfield's solitary hangar was then just a skeleton and still in the process of being erected. Most of the units arriving in the UK flew B-17 Flying Fortresses but the 93rd was the first to arrive with B-24 Liberators and within days had a fleet of 34 aircraft parked on the dispersals. Their olive drab camouflage contrasted with some of the colourful names which these aircraft carried, examples being 'Ball of Fire Junior', 'Shoot Luke' and 'Teggie Ann'. All of these had been flown across the Atlantic, but most of the unit's personnel sailed across on the 'Queen Elizabeth' and did not reach Alconbury until a fortnight or so later.
After a short period of training and familiarisation, the Liberators took off in anger for the first time on 9 October and undertook a raid on the steelworks at Lille. No less than 24 aircraft took part in this first B-24 bombing operation from Britain and one failed to return.
A major concern at this time was the growing threat of submarine attack on the all-important Allied convoys across the Atlantic and the Liberators made several raids on the U-boat bases at Lorient and St.Nazaire. During October and November detachments were also made to Coastal Command bases in south west England to fly anti submarine patrols over the invasion convoys heading for operation 'Torch', the invasion of North Africa. Following the success of this campaign, additional bomber forces were urgently needed in the Mediterrranean theatre and in early December the 93rd Group left Alconbury and flew to its new base in Algeria. One of its four squadrons (329th) was undertaking secret development work on navigational equipment so remained in England but was transferred to Hardwick in Norfolk.
In place of the Liberators of the 93rd came the B-17 Flying Fortresses of the 92nd Bombardment Group, which arrived on 6 January. This was a time when every effort was being made to build up the strength of the Eighth Air Force, but the combined effect of transfers of units to the Middle East and operational losses in the UK made it essential to improve the supply of new crews. As a temporary measure, therefore, the 92nd Group was relegated to perform an operational training role, three of its squadrons flying from Alconbury whilst a fourth (326th) was detached to Bovingdon for the same purpose.
Build up and Tragedy
In April 1943 the 92nd was joined here by a second B-17 Group, the 95th and for the next six weeks the airfield was crowded with the largest number of Fortresses ever based here, over 60 excluding those of the squadron outbased at Bovingdon. This placed considerable pressure on an airfield which was still far from complete, although at least two hangars were available for heavy maintenance by this date.
The new Group commenced operations from here on 13 May with a raid on the enemy fighter base at St. Omer and, taking advantage of the good weather conditions they flew missions for several days in succession, raiding targets such as Antwerp, Emden, Lorient and Flensburg. Tragedy struck the 95th on the evening of 27 May however, during the bombing up of the B-17s in preparation for operations the following day. For reasons never discovered, a 500lb bomb suddenly detonated and set off a series of lethal explosions. Eighteen personnel working on the ground in the area were killed and many more injured whilst four Fortresses were completely destroyed and another eleven damaged. This was a shattering blow, but operations continued regardless and only a day or two later the Group began moving out to Framlingham.
Meanwhile the 92nd Group had resumed front line operational flying on 14 May, when it took part in a raid on Kiel. At the same time the Group was selected to introduce the YB-40 into service. Twelve of these heavily armed 'Fighter Fortresses' had been delivered to Alconbury early in May and they were attached to the 327th Squadron with the intention of strengthening the defences of the large formations with which they were to fly. They first operated on the 29th may when seven YB-40s joined the B-17s in a raid on St.Nazaire. It immediately became clear that the extra weight of all their additional armament so dragged down their performance as to make them ineffective and although they continued to take part in raids during June and July they were then quietly withdrawn.
One of the last missions in which the YB40s participated was the raid on the synthetic rubber plant at Hanover on 26 July. As the formation approached the enemy coast this day, B-17 'Ruthie II' of the 92nd Group was attacked head on by Fw190s and the pilot was fatally injured in a hail of bullets. His co-pilot, Flying Officer John C.Morgan had the greatest difficulty in keeping control of the bomber due to the reactions of the dying pilot and he had to decide very quickly what could be done for the top turret gunner whose arm had been severed in the same attack. Other crew members meanwhile lay unconscious due to punctured oxygen lines. Having considered the implications of this desperate situation, the wounded gunner was successfully parachuted out of the aircraft, and was subsequently looked after by enemy medics. Morgan, then, despite the difficulties, somehow managed to keep pace with the rest of the bomber force and eventually made a successful landing at Foulsham in Norfolk. For this remarkable effort he was later awarded the Medal of Honour.
The 482nd Bombardment Group
On 20 August 1943 the formation began of the 482nd Bombardment Group, which was to become Alconbury's longest wartime resident unit. To make room for the new 482nd, the 92nd Group was transferred in September to Podington, which became its permanent wartime home. The new Group was meanwhile quickly established, not a standard bombing unit, but for the special role of developing the blind bombing aids. These were proving to be essential in order to keep up the bomber offensive in the cloudy conditions which were so often encountered in the skies of northern Europe. Consisting of three squadrons, two of B-17s and one of B-24s, the Group developed aids such as H2S, H2X and Oboe, often in close conjunction with British units working up similar equipment and techniques.
The new group's first operation was flown on 27 September, when four H2S equipped aircraft led the B-17s of the 1st and 3rd Divisions in a raid on Emden and over the next few weeks the 482nd provided pathfinder aircraft to take part in a number of Eighth Air Force raids. On 3 November, for example, when the target was Wilhelmshaven, aircraft from Alconbury led each of seven bombardment wings. At this early stage, considerable difficulty was experienced in achieving really satisfactory results but persistence with radar bombing would eventually pay off.
To improve upon the standard British H2S equipment, a shorter wave version known as H2X was progressively introduced in order to give a sharper picture of the target area. From early 1944 onwards this was fitted to the aircraft of the 482nd in a retractable radome which took the place normally occupied by the ball turret.
By the time the major campaign against the German aircraft industry commenced in early 1944, much progress had been made and in a typical operation on 11 January, fifteen Alconbury based pathfinder aircraft, including B-24s for the first time, led the way to the aircraft research establishment at Braunschweig for a large force of bombers.
Whilst having special responsibilities of its own, the 482nd also acted from November 1943 onwards as a parent unit for the formation of the Eighth Air Force's first two Special Duties squadrons, which were formed for clandestine supply dropping activities as a prelude to the invasion of Europe. A number of 'second hand' B-24s had become available as result of the takeover, from the USAAF, by the US Navy, of all anti-submarine operations from Dunkeswell in Devon and these aircraft were used to equip these new squadrons here. To disguise their true role they were designated the 36th and 406th Bombardment Squadrons, but once they had become operational in January 1944 they used the top secret RAF special duties base at Tempsford for their first supply dropping sorties. Soon afterwards they moved out to Watton.
In March 1944, aircraft from Alconbury bombed Berlin, but subsequently, since each Division now had pathfinders of their own, operating from Chelveston (B-17s), Hethel (B-24s) and Snetterton (B-17s), the 482nd was withdrawn from operations. It now had the all-important task of training enough crews to form one pathfinder squadron in each of the Eighth Air Force's forty bombardment groups.
The 2nd Strategic Air Depot
An important development at this time was the opening of a large maintenance depot in the area south east of the airfield. Provided with a purpose built complex of hangars, workshops and hardstandings, this replaced the outgrown temporary facilities which had been in use at Little Staughton and was opened in March 1944. Designated '2nd Strategic Air Depot' its prime responsibility was the heavy maintenance, repair and modification of B-17s from the twelve Groups which formed the First Bomb Division. It soon became quite normal for the depot to be handling up to fifty B-17s at any one time, many sent here for battle damage repairs from bases such as Molesworth, Thurleigh or Ridgwell. At the same time it handled an immense range of stores and supplies. It was operated by the 5th and 35th Air Depot Groups and as a large and important unit, with over 3000 personnel of its own, it was given its own identity of 'Abbots Ripton' in April 1944, even though it was located right alongside Alconbury airfield. The Air Depot Groups were important enough to have their own communications aircraft and it was a pilot from the 35th Group who took his Norseman to Twinwood Farm on 15 December 1944 and took off with Glenn Miller on what proved to be his final flight.
The Last Year of War
With the approach of the invasion in June 1944, preparations were made for the 482nd Group to re-enter combat and on D-Day itself the Group once again provided pathfinders, this time to lead bombing attacks on the massive coastal gun batteries which posed such a threat to the landing beaches. The Group also obtained thousands of radarscope photographs of target areas in France, Holland and Germany and whilst doing so it regularly bombed targets on the continent and also took the opportunity of dropping propaganda leaflets.
Training was still to be the Group's main activity, but development work continued as well and a good example of the new devices tested in the later stages of the war was AN/APQ7 'Eagle' radar. For this a specially modified B24 had subsidiary stub wings fitted to house the aerials.
Another secret unit, which arrived at Alconbury at the end of February 1945 was the Eighth Air Force's principal radio countermeasures squadron. Equipped with B-24 Liberators, this carried a designation which had been used before for another special squadron which had subsequently been renumbered as the 36th Bombardment Squadron. This unit was engaged in providing a force of specially equipped B-24s to jam enemy VHF communications during the big USAAF daylight raids. The squadron also flew regular 'ferret' sorties which set out to discover the frequencies being used by the enemy for their radio and radar devices. For this they used a number of P-38 Lightning twin boomed fighters as well as their B-24s.
By now the end of the war was at last in sight and at the end of April operational flying ceased. The Alconbury crews stayed long enough to celebrate VE Day, but all of the B-17s and B-24s took off for the USA between 27 and 30 May and the ground personnel were despatched to embark in the 'Queen Elizabeth' for the voyage home.
After seven years of ever increasing activity, the airfield settled down into a state of unaccustomed solitude and spent the next seven years in the hands of a Care and Maintenance party, under the control of RAF Maintenance Command.
Cold War Developments
It was not long after the end of World War Two that a new Cold War began to break out. The blockade of Berlin in 1948 made it all too clear that hostilities could begin all over again and that is exactly what happened in 1950 when Communist forces invaded South Korea. To prevent a similar invasion on the Continent, it was decided to re-establish a strong American force in Europe and on 24th August 1951, Alconbury was once more allocated for American use - now by the independent US Air Force. It was far from adequate in its wartime form, both in its flying facilities and in its accommodation, so plans had to be quickly drawn up for major expansion. One of the most notable features of this was the extension eastwards of the former subsidiary NE/SW runway in order to provide the 3000yds length which was now required for operations by jet aircraft.
This was a period in which facilities had to be rapidly provided for USAF flying units at Lakenheath, Sculthorpe, Manston, Wethersfield, Shepherds Grove and Bentwaters whilst the construction four heavy bomber bases in the Oxfordshire area was also being given a high priority. Although much work had been done at Alconbury by 1953, it was not until September 1955 that it was ready to house flying units again.
A Bomber Base Once More
The 7560th Air Base Group (ABG), 3rd Air Force formed as the station's host unit, but the first aircraft to be stationed here post-war were the North American B-45A Tornado, (a twin pod, four GE J-47 jet-engine bomber) of the recently re-formed 86th Bombardment Squadron. This unit was the third of the original four WW2 squadrons belonging to the 47th Bombardment Group. On reformation on 12 March 1951 it was re-designated as the 47th Bombardment Wing (Light) and a year later, moved to Sculthorpe, along with the headquarters of its parent formation, the 49th Air Division. This latter airfield was becoming overcrowded and it was decided to outbase one of its bomber squadrons to Alconbury, which took place during September 1955. The primary role of the 47th was an atomic one and a stockpile of nuclear weapons was accordingly held in secure conditions at Sculthorpe. It has not been confirmed that this was also the case at Alconbury, but in view of the responsibilities of the Douglas B-86BS, it seems very likely.
A second flying unit arrived in May 1957 - the 42nd Troop Carrier Squadron - and this was equipped with a mixed fleet of C-54 Skymasters and C-47 Dakotas. Formed at nearby Molesworth in October 1956, in order to meet the transport needs of the Third Air Force, this unit had a very short existence and was disbanded in December 1957. The following year the re-equipment of the 47th Bombardment Wing began and in May 1958 B-66 Destroyers began flying into Alconbury to replace the B-45s. The next development, between May and August 1959, was the arrival at Alconbury of the big WB-50Ds of the 53rd Weather Squadron which had been based at Burtonwood and were tasked with monitoring the ever changing Atlantic and European weather patterns for the Military Air Transport Service.
Tactical Reconnaissance - the RB-66
The year of 1959 proved to be a memorable one for the USAF in Europe as, following his election as President of France, Charles de Gaulle, insisted that all American nuclear forces be withdrawn immediately from bases on French soil. In the series of moves that followed, it was decided to transfer the 49th TFW, with its nuclear armed F-100s from Etain/Rouvres in France to Spangdahlem in Germany, after that base had been made available by moving the 10th Tactical Reconnaissance Wing to Britain. Alconbury was chosen to be the new base for the 10TRW and to release the capacity required, the two squadrons then resident here (86BS and 53WS) were transferred to Sculthorpe and Mildenhall respectively in early August 1959. Meanwhile, since the incoming 10th TRW consisted of four squadrons, two other airfields, Bruntingthorpe and Chelveston, were given up by Strategic Air Command and placed under Alconbury's control. No time was lost in making the transfer and by the end of August the new units were deployed as follows:-
1 TRS Alconbury
19 TRS Bruntingthorpe
30 TRS Alconbury
42 TRS Chelveston
The title of the 10th Tactical Reconnaissance Wing gives a good indication of its primary role and to undertake its photographic and electronic surveillance it was equipped with the Douglas RB-66B Destroyer. The basic aircraft was flown with a three man crew and was equipped for reconnaissance in all weathers and for camera work at night as well as during the day. The photographic compartment consisted of a fan of three cameras (two oblique and one vertical) supplemented by a very large single vertical camera, located in the fuselage section beneath the wing.
On arrival in England, most aircraft were still fitted with tail guns in a remote controlled barbette but these were subsequently removed and replaced by a special ECM tail unit. One of the four squadrons in the wing (42 TRS at Chelveston) was equipped with the RB-66C and WB-66s for electronic and weather reconnaissance. These aircraft carried an extra four crew members and were visibly recognisable by their wingtip pods, containing radar detection aerials and a variety of bulges protruding from the fuselage.
In 1962 a reorganisation of TR units took place and the 19th and 42nd Squadrons were transferred away to Toul-Rosieres in France, where they subsequently used to form a wing of their own. Back at Alconbury the 10 TRW soldiered on until 1965 with their RB-66s, which were comparatively large aircraft, derived originally from a naval medium bomber. Those in the 10 TRW were easily identified by their distinctive unit markings - a large Wing crest on the fuselage side and a plunging star insignia on the tail fin, together with coloured bands or signs to indicate their squadrons and/or flights.
The Arrival of the RF-4C Phantom
In 1965 the RB-66s were replaced by the much higher performance RF-4C Phantom. The new RF4Cs were essentially fighter aircraft, rather than bomber variants and flew in looking sleek and grey, but completely devoid of unit markings. This was the time of the war in Vietnam and it had been decided that the colourful liveries, which had for some time proliferated amongst all USAF flying units, should be replaced by low-visibility markings. Accordingly, it was not long before the 10th Wing Phantoms, like all USAF combat aircraft from this time onwards, were painted in the camouflage livery in which they would remain for the rest of their stay.
Having previously lost the 19th and 42nd TR Squadrons, the 10th Wing increased its strength again in 1966 by the addition of the 32TRS. This squadron had formerly flown RF-101 Voodoos with the 66TRW at Laon in France but was now equipped with RF4Cs like the other squadrons at Alconbury. At about this time a new form of distinguishing marking had made its appearance, in the form of a two letter code painted on the tail fin of each aircraft. Initially each squadron had its own code - AR, AS and AT for 1st, 30th and 32nd TRS respectively, but subsequently all combat aircraft based here carried AR. Squadron colours reappeared too in the form of a small coloured stripe on the tip of the tail fin of each Phantom and these colours could be seen gathered together on the three clusters of dispersals - 1 TRS (blue) behind the control tower, 30 TRS (red) on the north west side of the airfield and the 32 TRS (yellow) close to the main camp buildings.
For the next ten years the 10TRW Phantoms provided the bulk of all the airborne reconnaissance flying done by the USAF from the UK, and the RF-4C became the type which was based at Alconbury for longer than any other. Reconnaissance equipment was constantly improving and evolving and as well as conventional cameras, the Phantoms carried infra-red and electronic sensor (narrow to broad beam) scan systems. As result the individual aircraft in use by the wing were changed over time as they were withdrawn for modifications and were replaced by state of the art variants. The numerous missions required by NATO made it necessary for the RF-4s to range over a wide area and they operated at high speed, day and night, in all weathers.
Since the first manned space flight by Yuri Gagarin in 1961, enormous progress had been made in devising reconnaissance satellites and by the mid 1970s this was making it possible to reduce the numbers of front line TR aircraft. The first two months of 1976 accordingly saw the inactivation of the 30 and 32 TR Squadrons at Alconbury, after which the 1 TRS carried on alone to provide battlefield reconnaissance.
Taking advantage of the space now available, a new fighter squadron was formed here in April 1976 of a type which was unprecedented, in Europe, if not in the USA. This was the 527th Tactical Fighter Training Aggressor Squadron, whose task was act as aggressors in the increasingly lifelike training programmes devised to keep the operational USAF fighter wings on their toes. The 527th was equipped with 20 Northrop F-5E Tiger IIs to carry out their dissimilar air combat role and these were painted in four different and distinctive camouflage schemes. To reinforce the concept of dissimilarity they were also marked, Red Air Force style, with large double numeral nose codes.
There was some delay in reaching operational status, but in October 1976 the unit's first trainee wing was the 401st TFW from Torrejon in Spain. They were followed by visiting detachments of F-15s of the 36TFW at Bitburg in Germany and during the months to come most of the Wings in USAFE sent crews to Alconbury for air combat training with the 527th. There was, however, a limit to the number of visiting aircraft which could be handled here at any one time - about a dozen under normal circumstances. It therefore became normal, subsequently, for flights of four Tigers to be sent to visit the various front line bases in order to carry out training ‘on site’. The crowded European skies tended to limit this activity as well and ultimately an instrumented range was laid out in Sardinia and a training base, with a regular detachment of 527th aircraft and instructors was established at Decimomannu.
High Technology Surveillance
October 1982 saw the beginning of one of the most interesting series of operations ever carried out by Alconbury based aircraft. Under the overall control of the 17th Reconnaissance Wing, the 95th Reconnaissance Squadron was formed here at that time with a fleet of top secret TR-1s - an updated version of the very high altitude and long range surveillance aircraft better known as the U-2. The primary function of these extraordinary aircraft, with their ultra high technology equipment, was to fill a serious gap in the collection of intelligence, particularly in the troubled NATO Central region. Performance details are classified, but it is believed that the TR-1s had an operational ceiling exceeding 70,000 feet, a range of over 3000 miles and an endurance of 12 hours.
They are capable of being equipped with various 'packages'of highly sophisticated sensor systems and avionics, which can be carried in environmentally controlled fuselage mission bays, interchangeable nose sections and two wing mounted 'super pods'. Capable of collecting both signal and electronic intelligence (SIGINT and ELINT), the TR-1s main sensor can provide high resolution radar ground maps in all weathers over an area, it believed, up to 80 miles abeam of the aircraft's flight path. Most of this intelligence could then be immediately transmitted back to base.
Although it can 'fly like a bird', the TR-1 is an ungainly creature on the ground, with its combination of very large wingspan, very low wing position and light weight. The Semi-Hardened aircraft shelters built at Alconbury for the TR-1 had to be the largest in Europe, if not in the world and taxiing the aircraft out into the daylight and around the perimeter track was an art in itself.
As the TR-1 steadily became the principal mount for battlefield and tactical reconnaissance, so the demands on the RF-4 Phantoms decreased. Eventually, in May 1987, after twenty two years of constant service here, the 1TRS was withdrawn and the long familiar sight and sound of Phantoms disappeared from the local skies.
Meanwhile the title of the Tiger unit had long since been simplified to '527th Aggressor Squadron' and as such it continued to function, with its main base at Alconbury, until 1988, by which the F-5Es were feeling their age. It was therefore decided to re-equip the squadron with F-16 Fighting Falcons and after the last Tigers were withdrawn in September, the unit was transferred to recommence air combat training on its new aircraft at Bentwaters.
The Anti-Tank Warthogs
The next two squadrons to arrive came to undertake a completely different role. These were the 509th and 511th Tactical Fighter Squadrons, each armed with 20 A-10 Thunderbolts (often unofficially known as 'Warthogs' on account of their looks) and to reflect the new situation the 10th Wing was redesignated 10th Tactical Fighter Wing.
Tasked with the killing of enemy tanks and other armoured fighting vehicles, the A-10s could never be described as good looking, but they were truly formidable attack aircraft. Their main armament was a nose mounted Avenger seven barrelled cannon, which was capable of firing rounds the size of milk bottles at up to 4200 rounds a minute and in addition they carried AGM65 Maverick missiles and were able to deliver Mk 20 Rockeye cluster bombs. The 509th and 511st Squadrons arrived in April and July 1988 respectively and, as they had been doing before, maintained forward detachments of six aircraft at Ahlhorn in Germany to practice providing close air support for NATOs Northern Army Group.
The constant pressure on Alconbury's main runway inevitably made it necessary for major repair work to be undertaken and the airfield was temporarily closed for resurfacing between April and November 1989. During this period the A-10s were deployed to nearby Wyton whilst the TR-1s went to Sculthorpe.
The Fall of the Berlin Wall and the Gulf War
By far the most significant development of 1989 was the beginning of the collapse of Communism in Eastern Europe, symbolised by the destruction of the hated Berlin Wall. Immediate plans were made for significant cuts in NATO forces in Europe and very soon the first rumours began to circulate about the possible closure of Alconbury. Just as the cutting back process was beginning, Iraq invaded Kuwait, in August 1990, and the Gulf War began. Some of the first aircraft to be sent to the Gulf area were three TR-1s and they operated throughout the campaign from Taif air base in Saudi Arabia, which, at one time housed a dozen of these big black aircraft. Later, it became necessary to establish a force of 144 A-10s at Damman/King Fahd International Airport for ground attack and 23 of these were supplied by the 511st Squadron at Alconbury. This squadron flew no less than 1700 combat missions during 'Desert Storm' and played an important in wreaking havoc on Iraqi tank forces.
Immediately upon the return of the A-10s in May 1991, it was announced that the type would be withdrawn from Europe altogether and after their comparatively short but eventual stay at Alconbury, the two squadrons were withdrawn, the 509th in October 1991 and the 511th in March 1992.
A sizeable reduction was also made in the TR-1 force, which had, at its peak, in the late 1980s, consisted of up to 15 aircraft. At the end of June 1991 the 17th Wing was inactivated and the 95th Squadron transferred to the control of the 9th Strategic Reconnaissance Wing at Beale in California. Soon afterwards the special TR-1 (tactical) designation was dropped and all variants of the type were henceforth known as U-2Rs. A detachment continued to operate from Alconbury and the base also acted in support of the aircraft in transit between Beale and the continuing detachment in Saudi Arabia.
The Last Two Years - Special Operations
Meanwhile, one of the first bases scheduled for closure in the UK was Woodbridge in Suffolk. This housed two of the three squadrons forming the 39th Special Operations Wing, which had its headquarters at Rhein Main in Germany and it was now decided to bring the Wing together at one base - Alconbury. Because of the nature of their duties, the precise role of these units was inevitably shrouded in secrecy, but, in essence, they provided the means of delivering and retrieving special raiding parties to places behind the 'front line' at low level, in daylight or darkness and in all weathers.
Two of the Wing's three squadrons were equipped with special C-130 Hercules variants. First of these was the MC130E ('Combat Talon I'), which was primarily used for parachuting, re-supplying and extracting special forces parties from behind enemy lines. A sub variant was the MC130E-C, whose Fulton STARS recovery system, with its two prominent 'jaws' projecting from the nose, enabled two people or a 500lb package, to be snatched from the ground and pulled up to the aircraft. The second principal type of Hercules in use was HC130P/N ('Combat Shadow') whose prime tasks were combat search and rescue and tanker duties. In a large dome behind the cockpit, this variant was equipped with an AN/ARD-17 Cook Aerial Tracker, which was used to pick up the signals emitted by the search beacons carried by downed aircrews. The 39th Wing's third squadron flew the MC53J variant of the 'Jolly Green Giant'helicopter and so in 1992 the following aircraft were in use:-
7 SOS MC130E
21 SOS MC53J
67 SOS HC130N/P
Wing headquarters arrived first from Germany in January 1992, followed by the 21 and 67 SOS from Woodbridge in March, but the 7 SOS initially remained at Rhein Main. This was while it was equipped with the impressive MC130H Combat Talon II aircraft, with its state of the art terrain-following radar and improved night flying capability. A detachment also remained at Keflavik in Iceland and this was provided by the 67 SOS. For many years the helicopters of the 21 SOS had a straightforward search and rescue role, but in more recent times they had formed an integral part of the Special Duties force.
In the year before arriving at Alconbury, a large detachment of the 39th Wing had taken part in the Gulf War, operating from a base in Turkey. During their fairly brief stay in Huntingdonshire, however, the unit was principally involved in training exercises and during this period was also redesignated 352nd Special Operations Group. It is of interest to note that because of the potentially hazardous nature of recovery operations, pick up training was always carried out using dummies rather than real personnel.
The end was now in sight, however and by early 1994, plans had been finalised for the withdrawal of all USAF units from Alconbury and its outstations. One of the first to go was the 608th Contingency Hospital at Upwood which was closed in March that year and after months of running down, flying finally ceased in November, when the Special Operations units were transferred to Mildenhall. From then onwards came the massive task of clearing away all stores and equipment to enable the base to be vacated. In December 1995 the station was finally returned to the RAF, but British forces were also being cut back at this time and since the Ministry of Defence foresaw no future requirement for this long established airfield - indeed many others - Alconbury was put up for disposal. It was subsequently designated as a site for civilian development and was placed under the control of a consortium formed for this specific purpose.
Primary Units 1960-1996
10th Tactical Reconnaissance Wing (10th TRW)
The 10th Tactical Reconnaissance Wing arrived on 25 August 1959 from Spangdahlem, Germany and replaced the 7560th Air Base Group as Alconbury's host unit. It arrived with the RB-66s with the 1st Tactical Reconnaissance Squadron (TRS) from 8 December 1957 until 15 January 1988 and the 30th TRS from 8 March 1958 until 1 April 1976. In May 1965 the wing re-equipped with the RF-4C Phantom, after re-designating as the 10th Tactical Fighter Wing on 20 August 1987 and finally departed during November 1994. The wing acquired the 509th on 1 June 1988 until 30 December 1992 and the 511th on 1 September 1988 until 30 December 1992. The 527th Tactical Fighter Training Aggressor (later, 527th Aggressor) on 1 April 1976 equipped with F-5Es, provided 'dissimilar' air combat training for USAFE fighter and reconnaissance wings but departed on 14 June 1988.
The tri-wing configuration at RAF Alconbury was unique to USAFE. The 10th Tactical Fighter Wing (TFW), was the lead wing, hosting Strategic Air Command's Reconnaissance Wing and the 303rd Tactical Wing.
The 10th TFW commanded two squadrons of A-10 Thunderbolt IIs and an F-5 Aggressor Squadron. The 17th RW arrived on 17 February 1983 and flew the Lockheed TR-1 tactical surveillance aircraft. RAF Molesworth and the 303rd TMW at nearby is the home of the Ground Launched Cruise Missile (GLCM) (Europe's sixth and final GLCM). RAF Upwood housed a 2000-bed Fourth Echelon Hospital and was home to 221 military family housing units.
As part of the US military rundown in Europe, the A-10s departed in the spring of 1992, and the 10th TFW became the 10th Air Base Wing on 31 March 1993. To maintain the units heritage, the 10th Air Base to the US Air Force Academy, Colorado Springs, Colorado on 1 November 1994. In its place the 710 Air Base Wing formed as the host unit and then disbanded on 12 July 1995, upon the forming of the 423rd Air Base Squadron at Molesworth.
Reconstructing throughout Europe resulted in the RAF Alconbury flightline being handed back to the Ministry of Defence on 30 September 1995.
17th Reconnaissance Wing (17th RW)
The TR-1, made its first appearance in 1981, it is essentially the same aircraft as the U-2R but was designated as a tactical reconnaissance aircraft to differentiate it from the U-2 'spy plane' associated with Gary Powers. Strategic Air Command's 17th RW formed at Alconbury on 1 October 1982, bringing with it the TR-1. Aircraft designated as TR-1 were only assigned to the 17th RW.
During operation Desert Shield & Desert Storm, both TR-1 and U-2R designated aircraft were deemed as similar and as such were both considered as U-2s, parts and pilots were therefore, interchangeable between the two types. With the 17th RW's impending closure and the TR-1's transfer to the 9th Wing, the Alconbury aircraft were actually re-designated U-2R in October 1991.
The TR-1 was equipped with an electronic imagery system (sensor) Advanced Synthetic Aperture Radar System II (ASARS-II) which could relay imagery near-real-time to a fixed or mobile ground station (aircraft 'on tether') or if the aircraft is beyond the range of the ground station then the ASARS stored the information and then relayed it to the ground station when the aircraft gets into range. Unlike an earlier version fitted to the U-2Rs known as Senior Year Electro-optical Reconnaissance System (SYERS), the ASARS can 'see through' clouds, smoke and could be used at night. In the Gulf War the ASARS gathered imagery data and relayed it directly to the army's mobile Tactical Radar Correlater (TRAC). This system therefore was developed for tactical reconnaissance for the US army in Europe but was used operationally in a war situation over the Gulf.
On 23 August 1990 the first two TR-1s from the 17th RW arrived at Taif, Saudi Arabia and the TRAC van deployed to Riyadh. Intelligence officers in the van used information received from the TR-1 to direct strike aircraft to their targets. The first operational TR-1 ASARS sortie under peacetime applications of reconnaissance programs (PARPRO) rules, was carried out on 29 August. The limiting factor in the U2/TR-1 inventory was and is the sensors and the different types of sensors normally carried by the two types in the Gulf were often switched from one aircraft to another.
On 30 September the TR-1/U-2 unit had been designated the 1704th Reconnaissance Squadron (Provisional) with SYERS sorties by day and ASARS missions at night. By 16 January 1991, the 1704th RS (P) had flown 284 sorties and 2726.2 hours in support of Desert Shield.
With unique aircraft and such a limited inventory, spare parts were not readily available through the normal supply routes. In October 1990 the 17th RW at Alconbury therefore, commenced phase inspections of the 1704 RS (P) TR-1/U-2 fleet, the wing became effectively a parts depot and maintenance area for operations conducted from Taif. In normal training circumstances, the U-2 required a phase inspection every 200 hours with short flights and many 'touch-and-go' landings, but during operations with long flight times and only one take-off and landing per flight, the phase inspection interval was increased to 400 hours.
At the end of December the unit still only had five aircraft (two SYERS U-2s, one SPAN U-2 and two ASARS TR-1s) and 153 personnel. By 16 January this had been increased to nine aircraft and 231 personnel, including 24 pilots. During the five months of Desert Shield, U2/TR-1s had flown 284 sorties equating to 2726.2 flying hours.
Meanwhile, Resolution 678 had been passed by the UN Security Council on 29 November, giving Iraq until 15 January 1991 to comply with all previous resolutions, demanding an immediate and unconditional withdrawal from Kuwait. As a result President Bush announced the beginning of the Allied offensive on 16 January.
Switching from PARPRO to emergency reconnaissance operations (ERO) with the onset of war gave the U-2 authority to cross the border into Iraq. Almost immediately the U-2/TR-1s were tasked with watching for Iraqi troop movements and searching for Scud missile launching sites using the ASARS on-tether, passing real-time data to the TRAC van in Riyadh. Other missions included pinpointing Iraqi tanks and reinforcements during the ground war. At the end of the Gulf War the 1704th RS (P) had six U-2s, six TR-1s and 253 personnel, including 30 pilots, making Desert Storm the largest U-2 operation in history. In the six weeks of Desert Storm, U2/TR1 aircraft had flown 260 sorties covering 2022.5 flying hours.
The 17th Reconnaissance Wing disbanded in July 1991, but a subordinate unit, the 95th Reconnaissance Squadron, remained at Alconbury with the TR-1/U-2R until 1993 when it too disbanded. From 1993 to March 1995, U-2Rs of the 9th Reconnaissance Wing at Beale AFB, California deployed aircraft to Alconbury as its European outstation.
10th Civil Engineering Squadron (10th CES)
The 10th Civil Engineering Squadron and the British Property Services Agency managed all civil engineering projects carried out at the three primary sites as well as 11 separate and district housing areas and three communications sites. Other responsibilities included four collocated operating bases (COB) (at RAF Cottesmore, RAE Bedford and Bardufoss AS, Norway plus one other) and two forward operating locations (FOL) (at Ahlhorn, Germany plus one other).
The 10th CES consisted of 149 military members, 39 British and US civil servants.
Construction - WW2 Airfield
In 1942, the runway lengths were as follows:
Runway 1 1600yds by 50yds
Runway 2 1050yds by 50yds
Runway 3 1350yds by 50yds
The Air Ministry requirements of 1942 set the ultimate war-time standard for operational bomber airfields and until the end of the war all construction of new stations and extensions to existing airfields conformed to the new standard. This is known as the Class 'A' standard with a main runway having a nominal length of 2000yds and both subsidiaries with a length of 1400yds. Extensions were therefore carried out at Alconbury to bring the runways up to the latest requirements.
Still as an operational satellite airfield for Wyton during 1942, Runway 1 was extended by 350yds to the NE and Runway 2 was extended 300yds to the NW. Runway 3 had to be extended further north by 50yds to link up with the now extended perimeter track connecting with the new section of Runway 2.
On 1 December 1944 the runway lengths were as follows:
Runway 1 (06-24) 1950yds by 50yds (just short of the Class 'A' 2000yds)
Runway 2 (13-31) 1400yds by 50yds
Runway 3 (19-01) 1400yds by 50yds
In 1945 the Air Ministry had prepared plans (2970/45) for the extension all three runways to the new Very Heavy Bomber (VHB) standard having a main runway of 9,000ft and the two subsidiaries at 6,000ft, but nothing came of these plans. This would have been similar to the UK bases at Marham, Sculthorpe and Lakenheath. The next plan (2945/52), dated 1952 required the two subsidiaries to remain at their 1944 length and the main runway to be extended further east for a total length of 8,000ft plus an overrun of 1,000ft at either end.
The extension was to be served by two parallel 'high-speed' taxiways located north and south of the runway.
In 1953, two clutches of 20 pairs of dispersed aircraft hardstandings were built, the southern clutch were mainly arranged either side of the now abandoned Runway 3. The northern clutch were positioned along one side of the new northern perimeter track of Runway 2 and the now straightened out northern section of perimeter track belonging to Runway 1. These were each supplied with their own POL outlets set into the concrete floor.
The initial phase, under the financial year 1982 (FY82) Military Construction Programme, provided for 12 key facility projects at a cost of million. A second phase to support the long term TR-1 operation with new facilities was valued at million. This northside development involved the building of the following structures as part of a five-year NATO/US construction programme beginning (planning stage) in 1983 for the Strategic Reconnaissance Command's 17th Reconnaissance Wing.
Main TR-1 Projects
NATO Slice Description Total Cost
35 5 TR-1 Weather Shelters 7.4$M
35 Physiological Support Division
(soft facility) 2.4$M
35 POL storage (Phase 1) 1.7$M
36 POL storage (Phase 2) 1.8$M
36/37 13 semi-Hardened Aircraft Shelters 55.0$M
36/37 Taxitrack & platforms 8.0$M
31/35 Parallel taxitrack extension 4.5$M
35/36 Semi-hardened PSD/squadron Operations Building 8.0$M
37 Soft Squadron Operations 1.4$M
37 Hardened Avionics Maintenance 13.6$M
37 Hardened Sensor Maintenance 6.3$M
38 Vehicle Maintenance addition 5.2$M
38 POL truck shelters 0.3$M
38 Warehouse 0.5$M
Reactivation of Runway 23 for emergency use 1.7$M
Most of the above projects were financed through NATO funding with NATO slices 35 to 38 providing the majority of funds. USAF contributed over for additional operational facilities which included, chemical and biological decontamination cells for personnel and equipment installed in the avionics maintenance, sensor maintenance and PSD/squadron operations facilities.
The planning of the northside development in 1983 required 13 aircraft shelters to be placed at random around a new meandering perimeter track. No two sheds face the same direction so that in the event of a surprise attack by low-level enemy aircraft, it would only be possible to disable one shelter (with doors open) and its aircraft during a single run. The planning of the two lines of Weather Shelters (originally called TR-1 Conversion Shelters) is entirely different. These are soft structures and in a war situation were not to be protected and probably would not even be used.
Alternative Launch & Recovery Surface (ALRS)
The TR-1 is cross-wind limited and in order to increase the number of days the aircraft could be used during a crisis or war situation, it became necessary to provide a crosswind runway. One option under investigation during 1982/83 was to construct an entirely new runway, but this idea was rejected because additional land would have to be acquired from Lord Ramsey and negotiations were still taking place on the 33 acres of his land required for the avionics building. A cheaper alternative and less problematic option was to re-activate the wartime runway 23-05, but even this had problems. At the southern end of what was now called taxitracks 4 and 5, are five Tab-Vees Hardened Aircraft Shelters (14, 16, 19 & 21) which were required for the proposed move of A-10 aircraft from Bentwaters. As these aircraft were to be stored inside the shelters with their munitions and the fact that they are well inside the clearance zone for the proposed runway, they would violate both airfield and explosive safety criteria.
Eventually the idea of re-using 23-05 restricted to wartime use (or transition from peace to war) only was adopted. The runway was therefore designed as an alternative launch and recovery surface (ALRS) and reconstruction started in the summer of 1987. Criteria governing ALRSs were normally applied to fighter aircraft only and therefore the reactivation was tailored to the unusual requirements of the TR-1. Criteria such as runway dimensions, shoulders, clear areas, lateral safety zones, overruns and approach zones were all worked out to permit safe launch/recovery of the TR-1 within the unusual circumstances of Alconbury.
The reactivation also required that the site layout (November 1984) for four semi-Hardened Aircraft Shelters (Tab-Vees) (6,7, 8 & 9) had to be changed so that they were placed outside the clearance zone for this runway (requiring additional apron pavements). Furthermore, a runway overrun extension was built between shelters 7 & 8. The five TR-1 conversion shelters and TR-1 physiological support division & squadron operations complex were also re-sited 150ft from runway 23-05 edge to place it outside the clearance corridor.
Six months after reconstruction commenced the ALRS had been resurfaced ready for wartime operations. Even with the runway operational for wartime use, feasibility studies were carried out at the end of 1988 to determine what was required to upgrade the runway from ALRS to fully operational runway. There were two main reasons why it could not be used for peacetime use. The main one because the southern end was within one of the airfield's explosives clearance zone and compromised by the five aircraft shelters. The other being that even with a 519ft grass strip between the end of the former WW2 runway and the new overrun section built between shelters 4107 and 4108 only gave a overall maximum length of 5019ft (optimum runway length for a NATO Class 'B' runway being 6000ft). This figure was therefore well below for a contingency runway and would require the purchase of additional land from Lord Ramsey. In the event runway 23-05 was never used by the TR-1 under peacetime conditions and the shelters and the grassed area remained long after the base closed.
The transfer of the 509th and 511th Tactical Fighter Squadrons from Bentwaters to Alconbury required far less alterations and additions than the TR-1. Minor alterations were carried out to maintenance shops in building 52, two new NATO-funded 4-ship Arm/de-arm Pads, a new Squadron Operations Building and an extended Washrack. Munitions facilities were improved as well and this included a new gun room.
In accordance with other US bases in the UK Alconbury's last comprehensive master paint scheme was carried out between 1987/88. A neutral, soft tan colour was chosen to serve as a quite backdrop to blend and complement a dark brown trim colour. Over 100 facilities were 'transformed' to eradicate their formal drab tonedown greens and browns. The new scheme was designed to highlight desired architectural styles, and to blend with existing sheeting, brick colours while allowing creativity and flexibility if changes to the structure such as extensions were to be added in the future.
Defensive Fighting Positions
Sanction was sought during January 1988 for 18 pre-fabricated concrete defensive fighting positions (Pillboxes) to be erected to form a defensive perimeter as well as protecting the explosives areas.
Main projects at the end of the 1980s included a Burger King opened during September 1988, a new 7600sq ft, Commissary in 21 June 1988 and a new 230-bed Dormitory at the corner of Oklahoma and Oregan Streets.
Between April and October 1989, the 11000ft runway (including overruns) was re-surfaced and the two, four-ship Arm/de-arm Pads were built.
TR-1 Conversion Shelters/Weather Shelters
These have a rectangular planform, are of basic RSJ construction planned around four bays at 7750mm centres carrying simple and modern type steel trusses. Walls and roof are covered with the 'Kingspan' composite cladding system. Clear span is 38m and each one has a nominal clear door height of 7.5m. Balfour Beatty Construction Ltd built them during 1988. Perhaps their most interesting feature is the hydraulically operated 'Reflex' door manufactured by PJM Engineering of Diss in Norfolk.
TR-1 Tab-Vees/Semi-Hardened Weather Shelters
The first two to be completed were 4111 and 4112. 13 in all were constructed and all are extant.
Unlike most USAF aircraft, the TR-1 used (not any more) jet propellant thermally stable (JPTS) fuel.
TR-1 Physiological Building
As a physical environment, space begins around 125 miles above the earth; but as a physiological environment, it begins at 50000ft. Flying in this zone requires the protection of a full pressure suit to protect from the high altitude of hazards of the following:
The physiological support equipment the pilot wears creates an environment that minimises the impact (both physically and physiologically) of flying at extreme altitudes.
The pilot's pressure suit provides 100% oxygen at all times which as to start one hour prior to take-off. This prevents decompression sickness (the 'bends') by eliminating most of the nitrogen in the blood and hypoxia caused by lack of oxygen reaching the bodily tissues. Without a pressure suit in the event of a cabin pressurisation failure, the water in the pilot's body would escape as gas thereby causing damage to tissues and blocking blood flow but with a pressure suit the air trapped inside protects the pilot from decompression. The suit also prevents hypothermia and frostbite.
Despite all this protection, flying at extreme altitudes still takes its toll physiologically. Heat build-up, discomfort, fatigue, dizziness and dehydration to name a few are constant problems. Flying 9 + hours without drinking also compounds physiological problems. All normal physiological maintenance activities such as eating, drinking, urination are complicated when wearing the suit and can increase the stress and fatigue.
Denis Corley & Paul Francis