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Pulpits in the sky

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  • Pulpits in the sky

    An early attempt to produce a fighter might be summarised as ‘stand up and fire over the top of the propeller’. In 1914 a lightly armoured French Deperdussin two seat monoplane was modified to use this approach. As was the practice at the time the pilot occupied the rear seat with the observer in front just behind the engine; a metal tube structure rather like a skeleton lectern was fitted, in front of the observer’s seat, on top of which could be mounted a light machine gun. On approaching an enemy aircraft the observer was to stand up in his cockpit and fire the machine gun over the top of the propeller. This had the merit of mechanical simplicity but failed to take into account shifts in the centre of gravity and the change in the aerodynamic properties of the aircraft when the observer was standing. These could make the aircraft nearly uncontrollable and in danger of going into an unrecoverable spin. The aircraft was flown over the front lines but the pilot always gave the observer strict instructions to remain seated at all times no matter how tempting the target. At about this time Deperdussin himself was being convicted of major fraud and embezzlement and so had ceased to take a further interest in aircraft development. His company was taken over by SPAD who initiated an even weirder method of avoiding the propeller. We shall look at this a little later.

    In 1915 the Russians also adopted the stand up and fire approach. The Imperial Russian Air Service was using some Nieuport IX two seater biplanes. In these the pilot and observer shared a common cockpit, the pilot sitting in the rear. A rectangular hole was made in the upper wing, above the observer’s seat and a Madsen light machine gun fitted on a tripod mounting on the centre section. When attacking an enemy aircraft the observer stood up so that his head and shoulders were through the hole and operated the machine gun. Unfortunately the Danish Madsen was a very light firearm, and did not have the weight of fire or range to be very effective as an aircraft weapon. Worse still the effect of the observer standing up could cause the aircraft to go into an uncontrollable spin. Some Austro Hungarian and German aircrew must have been bemused at seeing a Russian fighter fly at them and then spin away to crash without them having had to fire a single shot in defence. Many of the Nieuport IXs were converted into single seat fighters with a machine gun fixed over the centre section.

    Austro Hungarian designers, limited by the lack of a synchronised gun, adopted a more robust form of stand up and shoot. A number of aircraft had streamlined ‘conning tower’ structures fitted to them. These had a top above the line of the upper wing (and the propeller). A gunner stood inside the tower and operated a machine gun. A small number of Hansa Brandenberg aircraft so fitted were flown and assessed in combat areas but proved ineffective (and unpopular) as the added drag significantly degraded performance. Moreover there was no effective communication or coordination possible between the pilot and the gunner on top of the tower. Some gunners had long pieces of string tied to the pilot’s arms; by pulling the appropriate piece they indicated directions to the pilot (whose forward view was in any case partly blocked by the engine housing). This was fly by string and not fly by wire and not likely to be conducive to an effective combat performance.

    Another approach can be reasonably dubbed ‘the pulpit solution’. In this the gunner is provided with a pulpit like construction from where he can fire the gun without danger of hitting the propeller. Pulpits were placed above upper wings, out on wings (one per side) and even out in front of the propeller. None of the aircraft fitted with pulpits were particularly successful, performance and handling characteristics were usually mediocre at best, and all exposed the gunner to considerable risk. It is actually surprising to see how many designers (some of them with considerable experience and reputation) adopted the pulpit solution. Yet despite all the inherent drawbacks some pulpit fighters actually saw action.

    In the first part of 1916 design work began on the Vickers FB 11 that was intended as a multi seat escort fighter to protect bomber formations; its fuselage was much like that of a conventional two seat fighter, albeit a somewhat large one, with a gunner sitting just behind the pilot and armed with a Lewis gun on a ring mounting. Synchronised guns were becoming available but instead of the usual fixed forward firing gun a pulpit was fixed to the top wing, protruding out beyond the leading edge. In this was seated a gunner armed with a second Lewis gun. This arrangement was intended to give the top gunner a 180-degree arc of fire that covered the entire front of the aircraft without the propeller getting in the way. A 250 hp. Rolls Royce engine provided the power. The top gunner was at considerable risk if the aircraft nosed over during landing and ended upside down (a not infrequent event for the aircraft of the time with rough grass landing strips predominating). The FB 11’s undercarriage was fitted with a skid, presumably to reduce this possibility, however with the weight of a gunner, gun and ammunition so high up and forward in the structure a summersault landing would have always been a risk. In his lofty pulpit the top gunner was totally isolated from the other crewmembers and any coordination would have been impossible. Given the shallowness of the top gunner’s pulpit standing up to operate the gun would put him at some risk if the aircraft had to undertake violent combat manoeuvres. The start of flight testing of the prototype was held up until the summer of 1916 because of delays in the delivery of the engine and by the time this had been completed new DH 4 bombers were entering service. These aircraft began a De Havilland tradition of building very fast day bombers (culminating in the Mosquito of the Second World War) and were the fastest operational bomber of the period As such they were over 40 mph faster than the FB 11 that was intended to escort them; with twin Lewis guns and a forward firing Vickers machine gun they were also more heavily armed. The DH 4 was able to out pace most if not all German fighters opposing it and was deemed eminently able to take care of itself (indeed on at least one occasion DH 4s provided top cover for Sopwith Camel fighters engaged in dive bombing attacks). No further development of the FB 11 was undertaken. The single prototype crashed sometime in 1917 and was written off.

    The Sopwith L.R.T.Tr was a huge triplane powered by a single Rolls Royce 250 hp inline engine and with a similar armament configuration to that of the Vickers FB 11 of which it was a contemporary. Its nickname in the company was ‘the eggbox’. It has been described as being the ugliest single engined fighter (despite considerable competition for this title). It was intended as a long range escort fighter. The very deep fuselage contained a fuel tank bigger than that carried by the day bombers of the day so one must wonder what it was supposed to escort that had such a long range. One possible explanation is that it was also intended to be another anti Zeppelin fighter, perhaps with a Davis gun in the above wing position. Its large fuel tank would allow it to loiter in the night sky awaiting an airship raid. It has also been suggested that it might also have doubled as a long range reconnaissance aircraft. The top gunner was housed in a large tear drop shaped housing (that also contained a large gravity feed petrol tank) high up on the upper wing and was even further away from other crewmembers than on the FB 11. In his very elevated position he was also even more at risk from a nose over (especially if night landings were to be attempted) and to try to protect against this eventuality the aircraft was fitted with a cumbersome four wheeled under carriage. This must have produced considerable extra drag and would adversely affect performance whilst being unlikely to be completely effective. Sharing his pulpit with a petrol tank cannot have done much for the gunner’s chances of surviving such and accident. In the days before self sealing fuel tanks the very large internal main petrol tank might also have been viewed as a significant hazard in the case of a take off crash (let alone from combat damage). Sopwith were very reticent about the L.R.T.Tr (possibly out of embarrassment) and there are no official reports on its performance and handling. A number of sources do suggest that it was a dangerous aircraft (for its crew rather than to the enemy).

    By the end of 1916 single engined fighters armed with mixed tracer and explosive ammunition were beginning to get the measure of the Zeppelin. The Bristol F2 fighter was already in production and this fast, manoeuvrable and heavily armed aircraft was more than capable of undertaking normal day bomber escort duties, reconnaissance and night fighting roles (plus many others). There was no role for the L.R.T.Tr and Sopwith never even submitted it for official trials. The L.R.T.Tr was retired to a hanger somewhere on the Brooklands aerodrome whilst Sopwiths got on with what they did well – producing superb single seat fighters

    Whilst Dutchman Anthony Fokker’s company was busy producing aircraft for Germany and Austro Hungary another citizen of the Netherlands was designing aircraft in Britain. He was Frederick Koolhoven who worked first for Armstrong Whitworth and later for the British Arial Transport (BAT) Company. Unlike Fokker (who took all the credit from his designers), Koolhoven did know how to design aircraft and in his own right could produce very effective warplanes (such as the Armstrong Whitworth KK 8 reconnaissance and artillery spotter). Unfortunately he had a thirst for innovative design that sometimes led him down some very strange paths. One of these led to the Armstrong Whitworth F K 12, surely a rival to the Sopwith L.R.T.Tr for the title of the ugliest single engined fighter.

    Produced in 1916 to meet the same basic requirements as the Vickers FB 11 and the Sopwith L.R.T.Tr, the FK 12 was an unequal span triplane (the middle wing was much longer than the bottom and top planes) with pulpits mounted under the port and starboard middle wing putting two gunners well forward. The pilot sat in an extremely commodious fuselage well behind the wings (presumably to prevent any possibility of fraternisation with the gunners). None of the aircrew could have had any effective means of communication with any other! There was no rear gunner which must have made this large and ponderous machine a sitting duck for a single seat fighter. Two prototypes were built both with the same general configuration.

    In the second aircraft the gunners’ pulpits were repositioned which brought each occupant within two feet of the of the engine’s exhausts thus adding carbon monoxide poisoning to all the other hazards of air warfare. Looking at the aircraft one wonders how the gunners accessed their isolated pulpits, ladders must have been necessary. The pilot sat in a very deep fuselage but the gunners’ pulpits appear to be very shallow so that the occupants must have been very exposed to the elements. The second prototype FK 12 made a small number of test flights, trundling around a few circuits of the airfield but it must have been obvious to all that there was no future for this portly warplane and no further development was undertaken.

    At least two types of aircraft had the gun pulpit placed in front of the propeller where it would both maximise the risk to the gunner and reduce to near zero his ability to communicate with the pilot. Strangely enough both saw some exposure to combat conditions and one went into production and was issued to squadrons on active service.

    The French company SPAD (Société Pour Aviation et ses Derives) was the successor to the Société Provisoire des Aeroplanes Deperdussin after the owner of the latter was convicted of massive fraud. It produced some of France’s most famous fighters of the First World War but before it created the hawks it first produced a real turkey. The SPAD A series (SA1, SA2, SA3 and SA4) introduced in 1915 were tractor biplanes powered by a rotary engine mounted slightly behind the wing leading edges (part of which were cut away to allow the propeller to rotate). Struts projected forwards from the undercarriage and the top wing to support a gun pulpit in front of the propeller. In the SA1 and SA2 a gunner occupied the pulpit and manned a Lewis gun on a rather complex mounting. The pulpit could create a problem for the air cooled rotary and scoops were fitted in its side to divert air back to the engine. The connection to the top wing could be disengaged and the pulpit swung down from the undercarriage to permit access to the engine for maintenance.

    With the engine and propeller between the pilot and the gunner there was no way at all that they could communicate. Any form of crash landing was almost certain death for the gunner, if the engine was still running on impact he would be chopped and diced by the propeller, if it was off he would be merely crushed. If enemy fire hit the connection to the top wing the pulpit fell forward and the aircraft became uncontrollable and crashed killing both pilot and gunner.
    The SPAD SA1 and SA2 were mainly distinguished from each other by the engine horsepower (the SA1 had 100 hp and the SA2 110 hp). About 100 were built and issued to French escadrilles where they immediately became extremely unpopular for the reasons described above. Their performance was in any case barely adequate and the Nieuport fighters fitted with an over wing gun were proving adequate to deal with the German Fokker Monoplanes. The French government applied what was a fairly consistent policy for dealing with French warplanes that the French forces did not want to the SPAD SA pulpit fighters and sold them to one of their allies, in this case the Russians. The Russian aircraft industry was incapable of supplying the needs of the Imperial Flying Corps for fighters and the Tsar’s government would accept almost anything with an engine, wings and a gun. The pilots and observers who had to fly them may have been less sanguine and the aircraft seem to have been no more popular than they had been with the French escadrilles. Nevertheless the Russian aircrew seem to have been more stoic and tried to make some use of the SPADs; a number were fitted with skis for operation from snow and ice. The SPAD A4 was a version produced specifically for the Russians and incorporated some improvements to improve the flow of air over the engine; only 10 of these were built. However there is only one instance on record of a Russian SPAD SA shooting down an enemy aircraft. As soon as Russian licence production of Nieuport fighters reached a viable level the SPADs were retired.

    The SPAD SA3 variant replaced the pilot’s position with another gunner’s position and provided duplicated controls in both gunners’ cockpits so that either could fly the plane when the other was using his gun. One has to assume that they agreed before take off who would actually act as pilot in the case of being attacked from the front and rear at the same time! Only one was built.

    The SPAD SG.1 variant replaced the gunner in the pulpit with three fixed forward firing machine guns, turning the aircraft into a single seat fighter with a powerful punch. French synchronised guns were becoming available by the time this had been done and the SG.1 was built only as a prototype, this was also sold to the Russians. What they did with it remains a mystery.

    In 1915 the Royal Aircraft Factory in Britain built the BE 9. This was almost certainly inspired by the SPAD SA series and was basically a BE 2c two seater with the observer’s position deleted and the engine moved backwards to bring the propeller almost in line with the leading edge of the top wing. Struts from the undercarriage and the top wing supported a pulpit in front of the propeller; these were less elegant than those fitted to the SPAD SAs but appeared to be more robust. The gunner’s pulpit was shaped very much like a hipbath, the rising back presumably protecting him from the propeller. The risks to the gunner were exactly the same as those afflicting the SPAD SA gunners. A number of leading RFC officers voiced their discomfort at the concept but despite this the prototype BE 9 was sent to the front for evaluation. A number of flights were made over the lines and attempts made to engage German observation aircraft. Unfortunately the BE 2c had never been the most sprightly of aircraft even in its usual configuration and in the form of the BE 9 it was handicapped by the extra drag of the pulpit, as a consequence the German two seaters that it was attempting to attack were much faster and easily able to stay out of range. The pilot’s forward view on the BE 2c had never been good; on the BE 9 it must have been nearly non-existent. Had a Fokker Monoplane attacked the aircraft the result would have been without doubt the shooting down of the slow and unresponsive BE 9. The DH 2 single seat pusher fighter was already in squadron service and quite capable of catching and downing enemy two seaters so that the BE 9 was a dangerous irrelevance and the idea was quickly dropped.
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    Last edited by MarkV; 04 Dec 15, 08:06.
    Human history becomes more and more a race between education and catastrophe (H G Wells)
    Mit der Dummheit kaempfen Goetter selbst vergebens (Friedrich von Schiller)

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