The R.A.F. Short Stirling

Some little known facts. The Stirling was the only aircraft to serve with Bomber Command in World War Two that was actually intended to carry four engines. Both the Lancaster and the Halifax started out life as two engined designs. The Stirling was also the tallest of any aircraft to serve with the RAF in World War Two - at 22 feet and 9 inches from the ground at her highest point, she cut an imposing sight to those not used to seeing her standing proud on her somewhat lanky undercarriage. Tip of the nose to the end of her guns at the tail was a shade over 87 feet, which made her the longest of any aircraft to serve with the RAF in the War. She had lovely clean lines, and everything seemed to be just in proportion. And finally, the Stirling, contrary to popular misguided belief, was actually a jolly fine aircraft. Although superceded by her sisters the Lancaster and Halifax in the second half of the campaign, she continued to give excellent service with the HCUs, Transport Command, and a host of other units and departments well past the end of the war.

The Stirling was the result of Air Ministry specification B12/36, which called for a "heavy bomber, capable of being launched via a catapult system, able to maintain height with one of its four engines shut down and carry a heavy bomb load, and have a wing span of no more than 100 feet." It was to be this last point of the specification which was to prove the Achilles heel of the Stirling in later years, but more of that later.

The name of Shorts was already well known in the aviation world. The marvellous Sunderland flying boat was already making friends with whoever flew in it, and in response to the above specification, Shorts produced plans for a heavy bomber that drew on some of the successful design points of the Sunderland. A wingspan of 112 feet was part of the design, and it was this point that the Air Ministry (AM) was opposed to. With almost characteristic lack of forward planning, the AM insisted on the maximum wingspan of 100 feet mentioned in the specification, in order that the Stirling would fit in the then standard RAF hangar. That this shortened wingspan could and probably would have some detrimental effect on performance (in particular the service ceiling of the aircraft) seemed not to have swayed the AM from their decision. However, revised plans were drawn up, and a final design chosen. And then a half scale model was built, capable of normal powered flight, so that the design team could see how well their new steed would handle in the air.

Known as "M4", the half size prototype made several test flights in and around Rochester, Kent (where Shorts had a large factory) in the autumn of 1938. As a result of these flights, several changes were made to the design of the Stirling, including lengthening the undercarriage struts, which were already long. This one modification alone was to have severe repercussions later on in the Stirling's life, as she gained a reputation for an unreliable undercarriage. However, generally things were looking good for the Stirling, and permission was given for a full size prototype to be built.

By this time war wasn't so much of an "if" as a "when", and so the RAF were keen to get their hands on some heavy bombers, and so it was that on May the 14th 1939, a whole four months before we would declare war on Germany, the Stirling was ready for her first flight. Assigned the RAF serial number L7600, she breezed into the air for a trouble free flight. Handling characteristics seemed to be good, and the test pilots seemed pleased with her. However, the joy was short-lived, as in some kind of premonition of the problems that would beseech her later life, the landing was a complete disaster. The undercarriage collapsed when the aircraft landed, and the resulting damage to the aircraft was so severe that she was scrapped. However, things weren't gloomy for long, and as the faulty parts were traced and replaced with better quality pieces, morale soon rose again at Shorts.

December of that year saw the second prototype completed, and on the 3rd of the month made her maiden flight. By this time of course, we were at war with Germany, and the need for a heavy bomber was becoming more pressing. The flight was a success, and off she went for further trials with the RAF at Boscombe Down. The first of the production models were soon coming off the line at Shorts, the first of these, N3635 making her maiden flight in May 1940. The only hiccup was in the engines - Bristol Hercules Mk.IIs were having to be fitted due to a delay in delivery of the Mk.III engines, and so the Short Stirling went into squadron service with Bomber Command. 7 Squadron, then resident at Leeming in North Yorkshire, were the first to equip. Not only were they the first to receive the Stirling, but with it they became the first squadron in the RAF to take delivery of a four-engined bomber. A great accolade, but one which manifested something of a problem. Who would fly the Stirling? Simply, there was no-one in Bomber Command who had experience of flying four-engined aircraft. Indeed, the only men who did have such experience, were those flying the Sunderlands and Singapores with Coastal Command. So, some of these Coastal Command men were seconded to 7 Squadron, in order that the process of converting men to four-engined types could begin.

As the spring of 1940 wore on, so 7 Squadron continued their training, but deliveries from the factory at Rochester were slow, and, in an effort to try and increase the numbers delivered to the RAF, Shorts opened up a second Stirling manufacturing plant at Belfast. Stirling production was still slow however, hindered by a bombing raid on the Belfast works which destroyed four of the type under construction there. The company's Rochester works were also attacked, damaging another six of the type, which led to construction of the type becoming dispersed (a precursor perhaps to her more famous sister the Lancaster), with components being constructed at various locations including Swindon (at the famous Great Western Railway's works), and Gloucester.

7 Squadron, who were still the only squadron formed up with the type, would have their Stirlings after all. However, things were far from rosy - by September 7 Squadron still only had three of the type on their charge (four had actually been received, but one had been lost in a crash), and mechanical problems were manifesting themselves all over the aircraft. All of these early Stirlings fitted with Hercules Mk.II engines were designated Stirling Mk.Is, and ostensibly to be used for training up crews only. The end of 1940 saw 7 Squadron at Oakington in Cambridgeshire receiving their first operational Stirlings fitted with the much-improved Hercules Mk.X engine and then in February 1941, after a couple of false starts due to bad weather, the Stirling went to war for the first time.

The night of the 10/11th of the month saw 7 Squadron dispatch 3 Stirlings, as part of a force of 43 aircraft, to attack oil storage tanks at Rotterdam. Not only was this the first time a Stirling had gone into battle, but it was also the first time a four-engined bomber had been used against a target in Occupied Europe by Bomber Command.

The Stirling beat the Halifax into operational service by exactly one month, the Halifax first seeing operational service on the night of 10/11 March 1941 against Le Havre. A few nights later a small force of bombers went to Boulogne on the night of 15/16 February 1941, and two 7 Squadron Stirlings contributed their worth to an attack on the docks of this French port occupied by the Germans.

The first time Stirlings operated as part of Main Force was on the night of 24/25 February 1941, when 3 Stirlings, again from 7 Squadron (still the only operational Stirling squadron) formed part of a force of 57 aircraft detailed to attack Brest. Of some interest is that this raid saw the operational debut of the Avro Manchester, 6 being detailed for the attack from 207 Squadron. It is interesting to note that Main Force at this time comprised just 57 aircraft - four years later as the war in Europe was playing out its final stages, Main Force would often comprise 700+ aircraft, almost 15 times the number sent to Brest on the night of 24/25 February 1941.

The reader will note that all of these early Stirling raids were to targets in France, but the Stirling was soon to see action over Germany. The night of 17/18 March 1941 saw N3652 from 7 Squadron act as the sole representative of the type on a Main Force raid to Bremen. Berlin, "The Big City", was visited by Stirlings for the first time on the night of 9/10 April 1941, when 3 of the Stirlings from 7 Squadron took off for operations against the German capital. 2 of the Squadron's aircraft aborted, and the third was lost to enemy action over Germany.

75 Squadron became the second Stirling squadron at the end of March 1941, becoming operational at the end of April 1941. The two squadrons were contributing Stirlings on a fairly regular basis to Main Force attacks, although not without losses. Berlin was visited again on the night of 30 April/1 May 1941, one of 7 Squadron's aircraft crashing on return to this country due to a shortage of fuel, and two nights later on the 2/3 May 1941, Hamburg was visited, with another of 7 Squadron's aircraft crashing in the UK, this time as a result of a Luftwaffe intruder aircraft, who shot down the bomber whilst it was in the circuit awaiting its turn to land. Only one of the crew survived the crash, to die the day after in hospital from his wounds.

Deliveries of the Stirling to squadrons, in particular the two operational ones, were slow, and especially if compared to the speed with which Lancasters were delivered to squadrons just two years later. By June 1941 only 57 had been accepted "on charge" by the RAF from the manufacturers. At this time Bomber Command were undertaking escorted daylight raids, codenamed "Circus" raids, and the Stirling was to feature prominently in these operations. These operations continued through the summer with the two operational squadrons putting up as many aircraft as they could. In October 1941 149 (East India) Squadron formed up with Stirlings, the third such to do so. On the 12th of the month the first two of the four-engined bombers arrived at the squadron, although it would be early 1942 before they were ready for operations.

On the 7/8 November 1941, 23 Stirlings were detailed for operations against Mannheim and Berlin. This was a new record for the number of Stirlings dispatched on a single night, although it is not as impressive as it might first appear. It had now been nine months since the type had entered operational service, so a record of 23 dispatched in one night was really quite unimpressive. However, this was no reflection on the aircraft - indeed it was a vast improvement over earlier twin engined types, and was far superior to the Avro Manchester which had entered service a short time after the Stirling and which was seen at the time as being the answer to all of Bomber Command's problems. No, the problem lay with the method of production of the Stirling. The Lancaster which followed it some time later employed "production line" methods of construction, whilst the Stirling was built up using more traditional "craftsmen" techniques. Each and every part put into the Stirling was made by a man who had perhaps served many years in his trade, hence the slower rate of build and delivery.

Away from the bombing campaign, trials were being conducted with the bombing and navigation aid Gee. It was first fitted to a Stirling (N3639) for airborne trials, which were successful and of course Gee was later to become one of the most successful airborne aids of the Second World War. 218 (Gold Coast) and 214 (Federated Malay States) Squadrons had both started to equip with the Stirling by the Spring of 1942, and at about this time a specialist Stirling repair facility was set up just outside Cambridge, in the heart of "Stirling Country". At about the same time, just as Sir Arthur Harris had taken the reigns of Bomber Command, a new record for the number of Stirlings dispatched in a single night was set, 82 taking part in "Operation Millennium" against Cologne on the night of 30/31 May 1942.

In August of the same year, the "Pathfinder Force (PFF)" was born, and of just four squadrons chosen to form the new target-marking elite, 7 Squadron and its Stirlings were one of them, and were destined to remain in the PFF for the duration of the war, giving up their Stirlings for Lancasters the following year. At the end of the year, two more squadrons were re-equipped with Stirlings, 75 (New Zealand) and 90 Squadrons both receiving examples of the new type to train up with. 75 (New Zealand) Squadron flew operationally for the first time on the night of 20/21 November 1942 against Genoa, and 90 Squadron going operational for the first time with the type on mine-laying duties off the Dutch and German coasts on the night of 8/9 January 1943.

Most people with a knowledge of Bomber Command will be aware of the famous "Battles" into which the Command entered at various stages in the war, engineered by their dedicated C-in-C Sir Arthur Harris. In the Spring of 1943, the first of these Battles commenced, with the opening of the "Battle of the Ruhr". During the previous winter Harris had concentrated on building up his force to one of some potency and strength, for what he hoped would be a concentrated effort against the German industrial heartland. The opening salvoes were fired on the night of 5/6 March 1943, when the Krupps Works in Essen became the focal point of 442 Bomber Command aircraft, 52 of them being Stirlings. But when it is realised that the Stirling had now been in operational service for two years, it is a slightly disappointing figure, although again, it is no reflection on the aircraft itself. Deliveries were still slow, and engine reliability had given some cause for concern during the previous autumn and winter.

The new Mk.III Stirling was now operating with most of the squadrons, and it was hoped would give improved climb, speed, and maximum ceiling capabilities. Loss rates were getting higher in the face of operating against the higher flying Lancasters and Halifaxes - the night of 14/15 April 1943 against Stuttgart saw 8 Stirlings lost from 83 dispatched, a loss rate of nigh on 10%. The night of 28/29 April 1943 saw 32 Stirlings dispatched on mine-laying duties, and 7 of them lost, an attrition rate of nearly 23%. However, the number available for a single raid was getting better, and on the night of 23/24 May 1943, in a raid against Dortmund, the number of the type dispatched exceeded 100 for the first time, when 120 made the trip, with 7 Squadron alone putting up 20 of the type - a marvellous achievement.

199 Squadron, later to become prominent in the radio counter-measure role, became operational with their Stirlings on the night July 30/31 1943, dropping mines in the sea lanes around the Frisian Islands. All returned safely to Lakenheath. Just a few nights earlier, on 24/25 July 1943, the Battle of Hamburg had opened, with 791 aircraft attacking the cosmopolitan city. 125 Stirlings were included in that total, and due to "Window" being used for the first time on this raid, losses were very much reduced compared to recent raids. Window was nothing more than strips of tin foil, but dropped en masse it threw the German radar system into complete disarray. From the 791 aircraft dispatched, just 12 were lost, including 3 Stirlings. At around this time, the number of Stirlings dispatched on any particular raid was generally just over the 100 mark - 119 went to Nuremburg on the night of 10/11 August 1943 (3 lost), 112 over the Alps to Turin on the night of 12/13 August 1943 (2 lost), and 124 to Berlin on the night of 23/24 August 1943 (16 lost).

Berlin was soon to become a regular destination for the crews of Bomber Command with the up and coming "Battle of Berlin", and this period of the war is often referred to by historians as "The Road to Berlin". However, as well as being a period of regular activity for the Stirling, it was also, per se, a period of high losses. From August to the middle of November the number of Stirlings lost was 109. Not many perhaps when compared with the number of Lancasters and Halifaxes that were lost over similar three month periods in the coming winter, but when expressed as a percentage of the total numbers operating, it was an alarmingly high figure. The problem wasn't that the Stirling was a bad aircraft, far from it, but because of the limited wingspan imposed on the type by the Air Ministry, it couldn't maintain the height of her four-engined sisters, and flying below them in the bomber stream, they were at the mercy of the ferocious German flak defences below. It was clear that something had to be done about the appalling loss rates, and as the number of Lancasters and Halifaxes available for operations grew, the Stirling would be withdrawn from bombing operations to Germany. But not before, they had the opportunity to play a part, albeit briefly, in the Battle of Berlin, the bloodiest period of the war for Bomber Command. The Battle of Berlin opened (depending on which version of history you subscribe to) on the night of 18/19 November 1943, with an all-Lancaster force, but a big diversionary raid saw 114 Stirlings attack Ludwigshafen and Mannheim as part of a force of 395 aircraft. 10 Stirlings failed to return to their airfields from this raid. The first attack by Stirlings on the "Big City" during the Battle of Berlin was on the night of 22/23 November 1943. This would also be the last time a Stirling would participate in bombing operations over Germany. 50 Stirlings made the journey as part of Main Force, alongside 714 other heavy bombers. 5 were lost, 10% of those dispatched.

However, contrary to popular belief, this was not the end of Bomber Command and RAF service for the Stirling. With their withdrawal from German operations came the opportunity to utilise the type on a number of other duties. Minelaying and Special Duties (such as those carried out by 138 and 161 Squadrons) operations kept the type and its squadrons busy. Bombing operations were still on the agenda too, with French flying bomb targets coming in for attention from the Stirlings and her crews. On the night of 16/17 December 1943, 26 Stirlings attacked the Flying Bomb site at Abbeville in France, without loss. Spring 1944 saw the type used almost exclusively on mine-laying operations, supplemented by Special Duties such as SOE (Special Operations Executive) agent drops. The 6th of June 1944 will be forever remembered as "D-Day", the long-awaited push by the Allies back into mainland Europe. 218 Squadron Stirlings played an important part in the run-up to the landings by dropping a very precise screen of window, confusing the German radar. It led the Germans into believing that the invasion was happening much further along the coast (Boulogne) than was actually the case. In the region of the landings, 199 Squadron, who had become a specialist radio counter-measures' squadron just a few weeks before, jammed German radar, affording the invasion flotilla and the bomber stream flying just ahead of it valuable protection. Glider-towing Stirlings of 38 Group also played an important part in the D-Day landings.

By July of 1944, most of the 3 Group squadrons that had been operating the Stirling had converted to the Lancaster, and just two were now flying the type - 149 (East India) and 218 (Gold Coast) Squadrons. Minelaying operations and Flying Bomb sites were the staple diet of the two units. The Stirling finally bowed out of Bomber Command service on the 8th of September 1944, a mere eight months before the end of the war. On the day, four of the type from 149 Squadron bombed German positions at Le Havre. All returned safely to Methwold.

The Stirling carried on important work in the transport role - the same month of September 1944 saw them dropping paratroops at Arnhem, and towing gliders with supplies to keep the offensive against the bridge over the Rhine going.

138 and 161 Squadrons mentioned earlier, were still busy in the Special Duties role at Tempsford, and along with the Stirling squadrons of 38 Group, had seen the number of Stirlings available to them increase as the Halifax Mk.IIs formerly operated by them had been reduced in number. Overseas, 148 Squadron was operating in the Special Duties role from Brindisi in Italy, whilst at Blida in North Africa 624 Squadron was formed up with the type for supply drops.

Then in January 1945 the Stirling found itself once again in the bombing role, albeit under the auspices of 38 Group and not Bomber Command. Operations were carried out against German troop positions in Belgium in support of advancing Allied ground forces. V-E Day saw the Stirling back in the transport role, ferrying supplies to Europe and bring POWs back.

Post-war, the Stirling commenced flights, again in the transport role, to India, Gibraltar, the Middle East and North Africa. The final user of this magnificent aircraft was 1588 Heavy Freight Flight, who finally dispensed with the services of the type in July 1946, more than a year after the war in Europe had ended. And so the Stirling story came to an end. That one was not saved for posterity, to be admired by future generations as an example of the first "Heavy" to see bombing operations in World War Two, is nothing short of one of the greatest travesties of our time. Even the original drawings no longer exist, being destroyed in a fire at the Short Brothers' works after the war.

There is a full size mock up of front fuselage section being reconstructed by enthusiasts, a slow and difficult task given the absence of plans and designers' drawings to work from, but we here at BCHS applaud the efforts of the team involved. The Stirling, more than her sister the Halifax, has passed into post-war obscurity. Often wrongly maligned, she made an important contribution to the war effort, at a time when Bomber Command's fortunes were not at their best. Had the later, more powerful versions of the Bristol Hercules engine been available earlier, had the wingspan remained at the designers intended 112 feet instead of being restricted by a short-sighted Air Ministry, had the bomb bay been built as a single, more capacious unit instead of being divided down the middle... History is full of such "ifs", but in the case of the Stirling, I am certain that had the above been so, then the Stirling would have ended the war with a reputation wrongly missing today, that of one of the RAF's "classics."

The above article is copyright © The Bomber Command Historical Society
and was first published in their newsletter in the autumn of 1999.