The Castle Bromwich Aircraft Factory

The Castle Bromwich Aircraft Factory

Spitfire Mk IIA P7350 – The oldest airworthy Spitfire in the world built at the Castle Bromwich ‘shadow’ factory, Birmingham. Entering service in the August of 1940, she flew in the Battle of Britain serving with 266 Squadron and 603 (City of Edinburgh ) AuxAF Squadron. (Arpingstone, Public domain, via Wikimedia Commons)

This paper briefly describes the history of the Castle Bromwich Aircraft Factory and its significant contribution to aviation, particularly during the Second World War.

The author of this paper has become acutely aware during the preparation of seven papers on the history of the Coventry based firm of Sir WG Armstrong Whitworth Aircraft Limited, that he has tended to neglect other aircraft manufacturing centres that were once active in the county. The writer of course refers to a period long before boundary changes removed significant parts of Warwickshire and reallocated them to the West Midlands. One such important manufacturing centre was the Castle Bromwich Aircraft Factory, situated in the district of Minworth, on the North Eastern fringes of Birmingham, which in the war years was firmly a part of Warwickshire.

It was at the Castle Bromwich Factory that a very significant proportion of the twenty-two thousand Vickers – Supermarine Spitfires and Seafires were built, during the years 1940-1946. In addition, over a slightly shorter period, just over three hundred Avro Lancaster bombers were also constructed there. Upon completion, every one of these aircraft was test flown from the airfield adjacent to the factory.

With the first flight of the prototype Vickers-Supermarine Spitfire, K5054, from Eastleigh airfield Southampton, on the 5th March 1936, it was immediately apparent to the management of Vickers Armstrong, the parent company of Supermarine, that they had a winner on their hands. However, a number of very important issues had to be resolved, including the need to develop the prototype aeroplane into a fully formed interceptor fighter and then produce it in quantity. In June 1936, even before the Spitfire had started it service trials at Martlesham Heath, the Air Ministry had placed an order for 310 aircraft. Additionally, Reginald J Mitchell, Supermarine’s Chief Designer, was seriously ill and time was short.

One of the major concerns surrounding the Spitfire was its relative complexity, particularly the construction of its wings, the machine requiring substantially more man-hours to complete than its less sophisticated stable mate, the Hawker Hurricane and its major opponent the Messerschmitt Bf 109. Additionally, Supermarine with its headquarters at Woolston, Southampton, and a factory at Hythe was a relatively small manufacturing organisation with limited facilities quite unsuited to high volume aircraft manufacture.

These were troubling issues and time was of essence. Eventually, the output of Spitfires from the Woolston works was supplemented by the opening in 1939 of the nearby River Itchen factory. Both these Southampton factories were destroyed by concerted enemy action on 26th September 1940, and on the orders of Lord Beaverbrook, Minister of Aircraft Production, were completely abandoned after the attack.

Beaverbrook personally visited the devastated Southampton works’ and ordered the immediate dispersal of Spitfire production. The Supermarine headquarters including the design office and experimental department were relocated to Hursley Park, a country mansion situated just to the south west of Winchester. Spitfire production was scattered across the south of England encompassing the counties of Berkshire, Hampshire and Wiltshire. Numerous garages and similar premises were requisitioned in these areas and production gradually recommenced. Fortunately by September 1940 another major Spitfire production facility was on stream.

The roots of aviation at Castle Bromwich appear to go back to January 1911, when a meeting of Midland Aero Club took place there. The location was subsequently examined by the Midland Aero Club secretary and found to be most satisfactory for their requirements, being about three-quarters of a mile in length by a quarter of a mile wide and flat and well drained. From March 1912 the Midland Aero Club were granted permanent use of the field, with the exception of weekends when football matches were being played – there were a large number of marked-out pitches on the site – so aviation had to vie with the national game!

Several aviators of note visited Castle Bromwich in these early years, including Robert Slack of the International Correspondence Schools and Bentfield C Hucks. Mr Hucks is credited with being the first British aviator to loop the loop. He is generally perhaps better known internationally for his invention of the Hucks starter; a device that permitted higher power aero engines to be started without resort to hand propeller swinging. Poor Hucks died at a comparatively young age in 1918, a casualty of the so called “Spanish Flu” pandemic. Very apposite!

Between the years 1912-1914 there were several aero gatherings at Castle Bromwich attracting large crowds. In June 1914 an air race with eight participants was conducted between London (Hendon) and Manchester (Trafford Park) via Castle Bromwich, where a compulsory stop of 30 minutes was stipulated.

With the onset of the First World War the military took over the airfield and the facilities were steadily developed, including the erection in 1918 of a large hangar to facilitate the assembly of aircraft, particularly the huge Handley Page 0/400 bomber, known as the “bloody paralyser”. These hangars after the war were to form the nucleus of what was to become the British Industries Fair (BIF), which opened its doors for business on 23rd February 1920. The BIF was to become an annual event; a fortnight’s celebration of the products of British ingenuity and industry, which flourished for many years and certainly continued well into the 1950s. The author as a boy well remembers attending several of the post war BIF’s and missed them when they were discontinued. Perhaps that was really the point when British Industry died?

In the nineteen twenties and thirties Castle Bromwich entered perhaps its “golden era”, when there were numerous flying events and attendances by privately licenced aircraft of all descriptions. These were the great days of private flying for the privileged few, who could enjoy the freedom of the skies in the pursuit of their hobby. But it was not to last, these halcyon days were coming to an end. With a deteriorating political situation in Europe it was almost inevitable that the Castle Bromwich site, due to its location on the edge of a great manufacturing conurbation, would be earmarked for future wartime industrial development.

The government in the late 1930s realising that the indigenous aircraft industry would not be able to fulfil the future requirements of the armed services if war came, decided that help that would be needed from elsewhere and turned to leaders of the motor industry for assistance. The aid enlisted from the motor industry was eventually to develop into the “shadow factory” system, whereby the government provided the finance to build the factories, which were then managed and run by the motor industry itself, to guidelines prescribed by the relevant government ministries. It was decided that a shadow factory for Spitfire production would be built at Castle Bromwich, to be managed by Morris Motors Limited, with Lord Nuffield at its head and overseen by the Ministry of Aircraft Production (MAP).

On the 15th July 1938 Sir Kingsley Wood, Secretary of State for Air, flew into Castle Bromwich to officially perform the ceremonial duty of cutting the first sod of turf for the new Spitfire factory. It was not a moment too soon! The factory of 135 acres, later to be considerably enlarged, cost over £3million to build and would eventually employ many thousands of people. Lord Nuffield saw to it that in true motor industry fashion the most modern machine tools were provided and everything, wherever possible, was jigged to the “Nth.” degree. In a previous paper the writer has indicated the importance in the aircraft industry of jigs, tools and fixtures to ensure complete interchangeability of components and assemblies. Lord Nuffield and his production engineers fully understood this and were confident in their approach to producing the Spitfire in volume – it was the way to do it. Unfortunately, they were wrong – at least initially!

Sir Kingsley Wood cuts the first sod of the site for the new aircraft factory at Castle Bromwich

When the Castle Bromwich factory was being built and tooled for production from 1938 onwards, the Spitfire was far from the finished article; indeed it perhaps could be argued that throughout its long, distinguished and much modified life the aircraft never achieved that “happy” condition. Aeroplanes, and particularly state of the art ones like the Spitfire, demanded constant modification to meet ever changing service requirements. For example, after extended trials it may be discovered that at an anticipated fighting altitude the guns are rendered inoperable because of insufficient hot air being ducted through to frozen breech blocks.

The modification to cure this problem may require changes to many wing rib diaphragms to permit more ducted hot air to reach the required locations. Every wing rib necessitated dedicated tools for its manufacture and hence the requisite router and press tools would have to be modified accordingly. All this took time and money, and in some instances it may not have been possible to modify the tools anyway! Therefore, new tools would have to be made – requiring even more time and money. Modifications are therefore an anathema to production engineers! The above is only cited as an example and may not hold strictly true for the Spitfire, although freezing of the guns was actually a problem on early machines and the hot air ducting had to be improved.

In the “cottage industry” atmosphere of Spitfire manufacture, such as that prevailing at Supermarine at Woolston, Eastleigh, etc, the above modification would have been relatively easy to incorporate by skilled fitters marking out the required new ducting hole positions and cutting the apertures by hand. This is all fine and dandy with a skilled workforce; the modification could probably be incorporated with the ribs in-situ in the wing, just prior to skinning. However, completion of a particular set of wings would be considerably retarded. Multiply this example many thousands of times and one gets an impression of the difficulties facing Castle Bromwich when it tooled up to make Spitfires using unskilled labour. Unfortunately, the design of the Spitfire was rather like a moveable feast, with all the contingent consequences.

The first variant of Spitfire Castle Bromwich was designated to produce was the Mk II. Outwardly there was hardly any discernible difference between the Mk I and Mk II Spitfires. The actual external differences being confined to a slightly blunter propeller spinner (probably made by CSA of Warwick for the constant speed airscrew) and a small blister on the starboard side of the engine cowling just aft of the spinner to accommodate the gear wheel train of the Coffman cartridge starter. Internally the biggest change was to the engine; a slightly more powerful Rolls-Royce Merlin XII with pressurised water-glycol cooling being installed. Undercarriage retraction was now performed by an engine-driven hydraulic pump; a great improvement on the hand operated variety installed in the very early Mk I Spitfires. In the early service days of the Spitfire take-offs were noted for their “switchback” like character, as pilots’ frantically hand-pumped up the undercarriage whilst doing the same to the control column!

Unfortunately, due to the production vicissitudes broadly outlined above, not one completed Spitfire had been produced at Castle Bromwich by early May1940. Lord Nuffield and his management team at Castle Bromwich were floundering. It was not entirely their fault and Vickers-Supermarine were far from guiltless, but there had to be scapegoats and the new Minister of Aircraft Production, Lord Beaverbrook, was taking no prisoners. On the 17th May 1940, just three days after his appointment, Lord Beaverbrook telephoned Lord Nuffield to ascertain why no Spitfires had left the plant. It was a fair question; the government had supplied the finance for a huge super-production facility and nothing at all had been delivered from it.

During the conversation Lord Nuffield told Beaverbrook that he could either have modifications or Spitfires, but not both. Then possibly thinking he was playing his ace card, Nuffield suggested, “Perhaps you would like me to give up control of the Spitfire factory?” Beaverbrook immediately retorted in his Canadian drawl, “Nuffield, that’s very generous of you. I accept”. The conversation terminated there! Lord Nuffield was shaken. So the motor industrialist and high-priest of production techniques was ousted and a new team was installed to get Spitfire production moving.

Lord Beaverbrook immediately handed Castle Bromwich over to Vickers for them to run. Vickers installed senior management and skilled staff from Supermarine to organise production. The directive was to produce 10 Spitfires by the end of June 1940. It was realised from the outset that this would be an impossible task using solely Castle Bromwich resources, and it was therefore necessary to bring in finished sets of components and completed fuselages from Southampton to enable the task to be accomplished. With much effort 10 Spitfires were indeed completed by the end of June. It was a start.

In his autobiography Sigh for a Merlin, Alex Henshaw, who eventually assumed the role of Chief Test Pilot at Castle Bromwich for the duration of the war, and came to know the Spitfire as perhaps no other, vividly describes the drive with his wife Barbara from Eastleigh to Castle Bromwich in June 1940, to test the plant’s second production Spitfire. When he arrived at Birmingham at first light the aircraft was not ready, with personnel crawling all over the machine, each getting in each others way! This pantomime continued for the best part of the day. Eventually, with the sun setting, Henshaw was offered the aircraft for test. The machine appeared to fly surprisingly well, and after a few minor adjustments had been made, Henshaw decided to give a demonstration of the Spitfire’s capabilities to the tired but expectant workforce. They probably witnessed one of the finest exhibitions of aerobatic flying that they would ever see; the display dramatically enhanced by the Spitfire cutting a swathe through a low evening mist that had settled across the airfield.

Henshaw’s return journey to Eastleigh with Barbara was almost a disaster; overzealous Home Guard personnel and police brought their car to an abrupt halt at Kenilworth, with a constable aiming a revolver at him. Henshaw was understandably shaken and very angry with the Kenilworth constabulary and Home Guard! Not all wartime Dad’s Army incidents were of the harmless slapstick humour variety. This was of course the time of heightened tension due to the threat of invasion and everyone was a little trigger happy!

It was realised that if Castle Bromwich was to run with any degree of efficiency and achieve its potential a compromise was going to be necessary; allowing for the fact that modifications were mandatory and had to be incorporated. Therefore, Castle Bromwich would manufacture those items that it was ideally set up to produce using unskilled labour, to be supplemented with components provided by the skilled labour force at both Castle Bromwich and Southampton. Using this approach the factory started to produce Spitfires in increasing numbers. In July 1940, 23 machines were delivered, followed by 37 in August and 56 in September. The first Squadron to receive the Mk II Spitfire was No. 611 based at Digby. Subsequently, No’s 19,74 and 266 Squadrons were to have the new Spitfire and it entered into the Battle of Britain in its closing stages.

The initial order for 1000 Mk II Spitfires was placed with Castle Bromwich in April 1938, before construction of the factory had even commenced! The actual breakdown of production was as follows: 750 (or 751 depending on the data consulted) were completed as the Mk IIa with eight 0.303”machine guns; 170 as the Mk IIb  with 2 x 20 mm cannon and four 0.303” machine guns; a further 80 machines were completed as the Mk V a/b. By March 1941 the Spitfire Mk II was being phased out in favour of the Mk V.

The Spitfire Mk V, destined to be the most produced version with over 5,000 built, was essentially a Mk I or II Spitfire with strengthened engine mounts to accept the more powerful and heavier Rolls-Royce Merlin 45 engine. As with previous Spitfires there were several sub marks viz, V a, b and c.  One version of the Spitfire Mk V for example had “clipped wings”, introduced to improve the rate of roll, although altitude performance was very slightly compromised. The Spitfire Mk V was introduced at about the time that Fighter Command was changing its tactics, going from a defensive to an offensive role, with sweeps over occupied Europe. Although the Spitfire Mk I had enjoyed a slight edge over its opponents in the Battle of Britain, with the Mk V version the aeroplane was becoming a little pedestrian. When this mark started to encounter a new German Fighter in combat it was shown to be demonstrably outclassed.

The new German fighter was the Focke-Wulf  Fw 190A series, a superb machine that outperformed the Spitfire Mk V in almost all respects, certainly at low to medium altitude. A smaller turning circle was the only real advantage the Spitfire enjoyed over the Fw 190. Consequently, Fighter Command’s losses started to mount.  The Spitfire Mk V served in nearly every Squadron of Fighter command and Castle Bromwich was fully occupied in producing them in large numbers.

Fortuitously, on 23rd June 1942 a Luftwaffe pilot who had become disorientated and erroneously thinking the RAF station at Pembrey in South Wales was his own base in France, landed his aircraft and thus unwittingly presented the British authorities with a pristine undamaged example of the Fw 190 A -3 (Werk-Nr 5313). This permitted the British to learn its secrets and fly the machine in comparative tests against Allied aircraft. In the short term this detailed information was used to formulate tactics to minimise, counter and nullify the Fw 190s obvious superiority. What really was needed was a vastly improved Spitfire!

Prime Minister Winston Churchill talking to Alex Henshaw, after a 1941 demonstration flight on a Spitfire. Source: Imperial War Museum online collection IWM Collection No.H 14264

Because the Spitfire had attained the status something akin to a national icon, it was inevitable that a number of important dignitaries would come to see the aircraft actually being manufactured. Castle Bromwich was therefore visited by such personages as the exiled King Haakon of Norway, Mrs Eleanor Roosevelt, Winston Churchill, Sir Oliver Lyttelton and the Lord Mayor of Birmingham. Churchill visited Castle Bromwich on September 26th 1941, having previously been the guest respectively of Armstrong Siddeley Motors and Armstrong Whitworth Aircraft at Coventry earlier on that same day. At Castle Bromwich Churchill was treated to a thrilling flying demonstration performed as usual by Alex Henshaw, the aerobatic maestro of the Spitfire. Henshaw almost made a fatal mistake in this particular aerobatic display by glancing at his watch during a critical manoeuvre, costing him vital altitude. He makes the point in Sigh for a Merlin that extreme concentration is required at all times, particularly in low level aerobatics. He was annoyed with himself that he had flouted this cardinal rule.

The constant production testing of Spitfires at Castle Bromwich was inevitably not without incident or accident, as Henshaw relates in his autobiography. Many of the incidents were of a routine nature concerning perhaps the trim of the aircraft, balance of ailerons, or other minor defects that could be easily rectified. Sometimes, however, they were more serious. Under the chapter heading, “Skewgear and Prop”, Henshaw relates two of the more serious types of problem that he and his team of test pilots encountered. The so called “skew gear problem” was one of considerable concern because it could happen suddenly, without warning, and manifest itself at the conclusion of an otherwise entirely satisfactory test flight. It was a fault that concerned the Rolls-Royce Merlin engine, which just stopped running and was described by Henshaw, “……as if the magnetos had been turned off.” It became such a cause for concern that Henshaw memorised suitable terrain, including roads, surrounding Castle Bromwich where a possible “dead stick” landing might be made in an emergency.

Perhaps at this point it would be apposite to give a brief description of what the skew gear did and the effects of its failure. At the rear of the R-R Merlin engine an internally positioned vertical upper shaft, geared to the crankshaft, delivered the drive via a pair of skew gears to the twin magnetos – one fitted on the port side of the engine and the other on the starboard. The vertical shaft continued upwards and terminated in a bevel gear which drove two inclined shafts that supplied the drive to the two overhead camshafts, one port and the other starboard. The magnetos were driven at 1.5 x crankshaft speed and supplied the ignition spark to twenty-four sparking plugs. In the event of any form of failure in the skew gears or the drive shaft both magnetos, at a stroke, would be rendered inoperative. This had the effect of cutting the ignition to the sparking plugs, and hence the explosive mixture in the cylinders was not ignited and the engine stopped.

Unfortunately for Henshaw, one of these many skew gear failures occurred over Willenhall, a densely populated part of the Black Country, with next to no opportunity for a safe forced landing. His Spitfire ended up in a cabbage patch in a small back garden, with both wings snapped off and the engine poking through the wall of a property whose garden Henshaw had just torn up! Very little of the Spitfire was left except the cockpit section in which Henshaw remained seated, doused in petrol! Realising he was still alive, Henshaw hurriedly released his Sutton harness and parachute and eased himself out of the cockpit and onto terra firma. Realising the aircraft was not going to burst into flames, he leant on the wreckage until assistance came. Although not seriously injured, Henshaw suffered severe bruising from the Sutton harness straps, which he had deliberately overtightened immediately prior to the crash. Henshaw’s wife, Barbara, was appalled when she subsequently saw photographs of the wrecked Spitfire.

After a seemingly long time the cause of the skew gear failures was determined; Rolls-Royce from Lord Hives down having pursued this mode of failure with vigour. The engines so afflicted were all from one source and it was discovered that they were being built in a manner different to that prescribed. It is possible that the skew gear backlash clearances did not conform to the specified tolerances due to the incorrect, reversed manner of build. Alex Henshaw must have felt some sense of relief; after all, one of these failures had nearly cost him his life.

Together with his fellow test pilots, Henshaw encountered yet another serious set of problems in the form of a spate of propeller malfunctions. The propellers failed when the blades suddenly changed into either coarse or fine pitch; the former stalling the engine and the latter causing the engine to dangerously over-speed and sometimes blow up. Both conditions necessitating forced landings. These were more tangible, obvious and sometimes noisy failures, as opposed to the silent and insidious skew gear problems. Nevertheless, the outcomes were just as potentially dangerous with the need to land the afflicted aircraft very quickly. The trouble emanated from faulty hydromatic valves in the airscrew.

The Spitfire Mk IX was initially introduced in 1942 as something of a stopgap to counter the German Fw 190, which was outperforming the Mk V Spitfire. The Mk IX airframe was suitably strengthened to take the increased weight and absorb the greater power of the Merlin 61 series engine with two-stage supercharger and aftercooler; the latter to cool and hence increase the density of the highly compressed charge prior to entering the cylinders.  In comparative trials against the captured Fw 190 A-3, the two machines were very evenly matched over the entire combat spectrum, each aircraft possessing advantages and disadvantages. On the whole, the Fw 190 was the more manoeuvrable, with better aileron control and rate of roll. However, the Spitfire at altitudes above 22,000 feet was superior in speed. These differences in performance were very small indeed and in the final analysis it was piloting skills that probably determined the outcome in combat. In the event the Spitfire Mk IX was an extremely effective stopgap and continued in production until the end of the war. Alex Henshaw records that he flew the first Castle Bromwich built Spitfire Mk IX in March 1943.

The Castle Bromwich plant suffered only one really damaging air raid and that occurred during 1940, when 11 workers were killed and a further141 were injured.  However, there was never a serious attempt at a knock-out blow, such as that administered to the two Southampton works in September 1940. The Germans certainly knew of the importance of Castle Bromwich and had target photographs of the Spitfire works, flight shed and airfield. It is a little hard to understand, in fact it is almost inexplicable, why the enemy did not press home its advantage at that critical time. If they had bombed both the Castle Bromwich and Rolls-Royce Derby plants sufficiently early in the war, using radio beams to locate the respective targets with precision, the situation for Britain may have become very difficult indeed. Fortunately for Castle Bromwich and Derby, it was a very serious German tactical misjudgement. Air raids, however, were an ever present threat which often necessitated the rapid dispersal of aircraft awaiting test on the Castle Bromwich flight line!

One of the senior flight shed team at Castle Bromwich during the war years was a man called Jim Hastings and he is mentioned several times in Henshaw’s autobiography, Sigh for a Merlin. When an apprentice at Hawker Siddeley Aviation, Bitteswell, the author of this paper became acquainted with Jim, who by then was probably in his sixties. He was a tall, ruddy complexioned man with a shock of fairish hair and a northern (Yorkshire?) accent. Jim Hastings had probably arrived at Castle Bromwich via Supermarine, where the author thinks he may possibly have worked on the Schneider Trophy Racing Seaplanes, produced by the company in the late 1920s. The author’s one regret is that he did not converse with Jim a great deal more on aspects of his working life at both Supermarine and Castle Bromwich. Alas, that information is now lost to posterity. Indeed, if he had written this paper it would have been far more illuminating! Jim was a fine man and the author is proud to have known him.

In days of yore, when the wonderful old Birmingham Science and Engineering Museum existed in Newhall Street, it had amongst its many somewhat haphazardly presented treasures a Castle Bromwich-built Spitfire. Associated with the exhibited Spitfire was a wooden trophy-type plaque, with many signatures upon it, probably of flight shed personnel at Castle Bromwich during the war years. It is a very long time since the writer last saw that particular item, but feels sure that among the many inscribed signatures was that of Jim Hastings. The writer has never visited the Think Tank since it moved from Newhall Street, and has no intention of doing so. Apparently, the Spitfire is exhibited at the Think Tank, but whether the plaque is on display is not known.

Castle Bromwich, in addition to the production of Spitfires, also manufactured the Avro Lancaster bomber and by the termination of the war had constructed just over 300 of them. In Sigh for a Merlin, Alex Henshaw discusses how he frequently barrel-rolled Lancaster aircraft that he was testing. His view as Chief Test Pilot was that this manoeuvre imposed no undue stresses on the airframe, if done correctly; the emphasis being on, if done correctly. Some years ago the author of this paper discussed this very point with Mr Henshaw, and he reiterated what he had said in print, that the stresses imposed were very small indeed, probably not more than Ig, and well within the Lancaster’s capability. A typical Lancaster in service would have been subjected to far higher stresses and strains when, for example, being severely dived or “corkscrewed” to avoid enemy fighters. Anyone who has ever attempted to clamber over the Lancaster’s massively deep wing spar, which passes right through the fuselage, will be struck by the sheer strength of the aeroplane. It was not the type of aeroplane that was just going to fall apart as a result of benign aerobatics!

Alex Henshaw’s last flight from Castle Bromwich, in January 1946, was in a contra-rotating propeller Spitfire Mk 22, LA 449. It was hardly believable that its antecedent was the Mark II Spitfire, which had been first produced with so much difficulty in June 1940! It was a far more powerful and heavier machine; much faster, with a higher operational ceiling and packing a heavier punch, and yet for all of its superiority most of R J Mitchell’s original Spitfire magic had gone! It had been a very intensive number of years for Henshaw personally, and for the entire production team at Castle Bromwich. Under the pressures of war they had manufactured and tested one of the world’s greatest aeroplanes, and had helped to keep it ahead of the opposition for most of that time.

Between June 1940 and January 1946, approximately11,750 Spitfire and Seafire aircraft were produced at Castle Bromwich, and its dispersal factories at Cosford and Desford. Another source is more precise and suggests 11,694. Whatever the actual figure, it represents more than half of all Spitfires manufactured and included, Mks II, V, IX, XIV, XVI, 21 and 22. Additionally, 305 Lancaster bombers were also produced. This was a tremendous midlands contribution to the British war effort.

At the conclusion of aircraft production in 1946, the Castle Bromwich factory was acquired by Fisher and Ludlow and turned over to the manufacture of car body pressings and body shells for the British motor industry. Fisher and Ludlow subsequently became Pressed Steel Fisher and was itself ultimately absorbed into the British Motor Corporation, later to become British Leyland. Dunlop, an adjacent company, purchased part of the site for its development department. In 1977 the plant was taken over by Jaguar, who now occupy the site.

After the war the Castle Bromwich airfield remained open, playing host to various organisations associated with flying. Battle of Britain “At Home” days were particularly popular during this post war period, with many thousands of people attending these annual events. However, by 1958 the sole users of the airfield, at weekends, were the Birmingham University Air Squadron. British Industry Fairs (BIF) continued at Castle Bromwich until at least 1957. In 1960 the airfield was sold to Birmingham Corporation for housing development and this culminated in the present day Castle Vale Housing Estate.

Apart from Alex Henshaw’s lucid autobiographical account, there has been very little other first hand material on the subject of Castle Bromwich during wartime and it seems fairly unlikely that other authoritative narratives will now surface, although it could happen. Another equally vivid account of testing the Spitfire by Jeffrey Quill, Assistant Experimental Test Pilot at Vickers Armstrongs, gives the almost parallel Supermarine side of the story. There are, of course, facts and figures type books galore, but very little from the personal angle recording the day to day vicissitudes of actually producing aircraft like the Spitfire. This is a great pity as the Second World War was just as surely won in the design offices’ and manufacturing shops of Britain as it was in the actual war zones.

Alex Henshaw – Chief Test Pilot

Alex Henshaw, c. 1941

Alexander Adolphus Dumphries (Alex) Henshaw was born in Peterborough in 1912, the eldest son of a wealthy Lincolnshire family. As a boy he attended for a time the King Edward the VI  Grammar School at Stratford upon Avon, sitting in the famous bard’s desk. He also attended Lincoln Grammar School. Always keen on aviation he obtained his pilot’s licence in 1932 and at the age of 20 competed in the 1933 King’s Cup Air Race. He set his heart on winning the King’s Cup, and this he achieved in 1938. In 1939, piloting a suitably modified Mew Gull aircraft, he established a world record flight from London to Cape Town and back. This record stood for more than seventy years. With the onset of war he considered joining the RAF, but lacking service experience thought he may be of more use as a test pilot. He joined Vickers – Armstrongs Limited at Weybridge in Surrey, test flying Wellington bombers. Becoming somewhat bored with this work he accepted Jeffrey Quill’s offer to join him at Southampton. Here he test flew Spitfire and Walrus aircraft. Subsequently he was offered the position of Chief Test Pilot at Castle Bromwich, a post he occupied until 1946. Henshaw records that he personally flew 2,360 different Spitfires and Seafires, representing more than 10% of the grand total of aircraft produced.

Post war he briefly became a director of Miles Aircraft, and following its financial collapse continued with his own business and farming interests in Lincolnshire. Very surprisingly, still only in his mid thirties, he gave up piloting aircraft. For his work in the 1953 East Coast Flood Disaster he was awarded The Queen’s Commendation for Brave Conduct.  He wrote three autobiographies; Sigh for a Merlin (1979) Flight of the Mew Gull (1980) and Wings Across the Great Divide (2004). In recognition of his services during the war he was awarded the MBE. He died in 2007 aged 94.


  •  Sigh for a Merlin, Testing the Spitfire, Alex Henshaw, John Murray,1979
  • The Spitfire Story, Alfred Price, Arms and Armour Press,1982
  • Spitfire, the Story of a Famous Fighter, Harleyford, 1960,
  • Spitfire, A Test Pilot’s Story, Jeffrey Quill, John Murray, 1983
  • Rolls-Royce Merlin 45-55M, Aero Engines, Manual-Air Ministry Publication, April 1941
  • The Focke-Wulf  Fw 190, Gordon Swanborough and William Green, Purnell Book Services, 1976
  • Warwickshire Aviation, Alfred J Jenks 2020

Copyright © J F Willock January 2021

Alex Henshaw flight testing a MkV Spitfire at Castle Bromwich Birmingham 1941.
This ( apart from a few brief seconds with XF) is the only known footage of him actually flying.

The Sentinel monument on Spitfire Island, Castle Bromwich, Birmingham commemorates the manufacture of almost 12,000 Spitfire fighter aircraft by Vickers Armstrong at this site between 1940 and 1945. The sculpture was designed by Tim Tolkien, great nephew of J R R Tolkien author of The Lord of the Rings and was unveiled in October 2000 by Alex Henshaw the former chief test pilot at Castle Bromwich aerodrome.

An interesting illustrated history of Castle Bromwich Aerodrome 1914 – 1958 is available here.