10.31. Dealing with present problems does not mean not working on the future.
It was late at night and Sir Phillip was still working through his Parliamentary boxes, once more he thanked his good fortune that he had a good team of civil servants who not only winnowed out the politically inspired dross but also prepared succinct summations and briefing papers on each report and proposal. One report had caught his eye, it was one of the regular updates upon the latest fighter aircraft project undertaken by the Marin Baker aircraft company. This current project had resulted from the failure of the earlier MB 2 project built as a private venture to fulfil specification F5/34 to generate any orders or real interest from the RAF, as it failed to offer any advantage over the new Spitfire and Hurricane that were then entering service. Returning to his drawing board James Martin had drawn up plans for a new aircraft using the latest new and more powerful engines available to provide a fighter that exceeded the performance parameters of any fighter yet designed to an Air Ministry Specification as set out by the requirements of specification F18/37. To this end in late May 1939 James Martin and Valentine Baker had presented their proposal for their MB3 fighter using the new RR Griffon engine. This design had generated much interest within the AM but concerns were raised about the choice of the RR Griffon as Earnest Hives at RR had already informed the AM that with the need to concentrate resources in developing the Merlin engine, that despite the cancelation of the Exe and the Vulture engines, production Griffon engines would be unlikely to be available before the first quarter of 1942. To expedite development of the MB3 RR had agreed to provide several of the most powerful version of the RR Merlin at the time of the construction of a protype.
One faction within the AM and RAF was at this time pushing the new Sabre engine from Napier as the powerplant of choice for future fighters and recommended that the MB3 design be modified to use it. With the demise of the RR Vulture the Hawker Tornado fighter design to F18/37 had been changed from using that engine to the Fairey Monarch engine whilst the Typhoon aircraft used the Napier Sabre. To mirror this a proposal was generated within the AM to order three protypes from MB aircraft all to share the same basic modular design and ease of construction as previously demonstrated by the MB2 but each to have a different engine installation. So the RAF’s preferred option of the Napier engine would be designated the MB3 and the Fairey Monarch engine version would become the MB4 with the RR Griffon aircraft being given the MB5 designation. The MB3 and 4 prototypes were to be built in parallel whilst the MB 5 would be allocated materials and resource compliant with the progress RR made on the Griffon engine. So in June 1940 contact 1165/39 was awarded to M&B for the three protype aircraft and final design work on the first two proceeded apace.
Well aware of the very negative effect the Dagger engine had had on the MB2 project and the recorded reservations of both James Martin and Valentine Baker in Napier’s ability to deliver a reliable production engine, Napier with the sanction of the AM had assigned Arthur Hagg an aircraft designer recently poached from De Haviland and an expert on engine cowling and cooling systems to act as their liaison with the Martin Baker company. At his first design meeting with James Martin, Arthur Hagg, on behalf of Napier’s ( with the slightly reluctant agreement of Heston aircraft and Lord Nuffield) had shown James Martin the drawings and specification of the Napier Heston Racer aircraft that was at that time being constructed. The two main points of interest in this design were the low drag wing section and the advanced aerodynamic cooling system. The wings of the Napier Heston were designed for high speed being a thin section airfoil having a thickness to cord ratio of 16.2% at the wing root and only 9% at the tips more unusually the maximum thickness of the wing was designed at 40% of the cord. This was much further aft on the wing than most airfoils at the time. To further reduce drag on the Heston designed aircraft Hagg had helped to design a then novel cooling system, this consisted of a special Galley radiator matrix buried in the fuselage well aft with an air intake on the underside of the fuselage approximately level with the rear or the wing roots, this intake was designed with ducting within the rear fuselage that was designed to slow the air by about two thirds before it past through the large area V shaped Galley radiator matrix at speeds of around 3 MPH before being exhausted out of the rear fuselage. Whilst this exact design might not be suitable for a fighter aircraft Arthur Hagg assured James Baker that a modified version of the system would result in much less drag than a conventional radiator system. After much discussion and checking of figures and calculations James Martin had incorporated these ideas into his design and had forwarded the revisions to the AM for approval. The drawings had been forwarded to the Royal Aircraft Establishment at Farnborough and to the Aeronautical Research Committee for their comments in mid June 1939. As Chair of the Aeronautical Research Committee (amongst several others) Sir Henry Tizard had reported on the finding of the committee. These were that the benefits of applying these advanced design features to a new fighter design were justifiable and could result in an aircraft of remarkable speed and performance. Further the committee recommended that immediate work be done in the wind tunnel at the RAE, to verify the figures and also to investigate whether the Meredith effect could be exploited to further reduce the cooling system drag. It was further recommended that official support for the Napier Heston racer should be forthcoming as a proof of concept aircraft and that it be completed to flight status as soon as possible. Tizard also noted in his report that the engine sub committee of the Aeronautical Research Committee also recommended the AM provide support for this aircraft so as to get at least one example (even if it is a hand built special racing engine) of the Napier sabre engine flying as soon as practicable. This approval and support for the Napier Heston was about to be approved in august 1939 when the critical political situation in Poland intervened. Despite this resources were made to enable work on the aircraft to continue.
Work on the final design of the MB3 and 4 continued whilst the RAE carried out wind tunnel tests on the proposed radiator system. By early 1940 this research had been completed and the Aeronautical Research Committee had undertaken a review of the results and passed their recommendations on the AM and to MB aircraft.
By happenstance in late April 1940 Sir Winfred Freeman had signed a contract with North American Aviation to build a new fighter to a British specification. Preliminary designs for this aircraft had been sent to the AM in April and these had been sent to Tizard and the ADC for their comments. The Basic conceptual similarity between the North American design and the Martin Baker MB3/4 and 5 was immediately noted and a complete comparative analysis of the design of both aircraft was recommended.
The fall of France and the invasion panic had threatened the progress of these projects but after a short hiatus work on both the Martin Baker fighter aircraft and the Napier Heston had resumed. So in late June of 1940 Sir Phillip and a number of other senior people in the AM, MAP and the RAF had been invited along with James Martin and Valentine Baker to the airfield at Heston to witness G-AFOK’s first official flight. Taxing and other ground trials had been proceeding for some weeks in preparation for this flight and there was high expectation as the chief test pilot of Heston Aircraft Squadron Leader G.L.G. Richmond lined up the aircraft at the end of the runway. For this first test flight the cockpit canopy had not been fitted and there was just the wind screen that had been fitted for the ground trials.
As the throttle was opened and the noise from the large H form Napier Engine rose from a growl to howl as the variable pitch three bladed De Haviland propeller transmitted some two thousand horse power into thrust. The little aircraft seemed to leap forward like a sprinter out of the blocks and gathered speed remarkably quickly. Despite the Engine weighing 2,900lb and constituting some 40% of the entire aircraft weight it was still a very light aircraft for the power and very soon the wheels were clear of the ground as the aircraft climbed gently, for this first flight there was no intention of raising the undercarriage and the flying speed was to be kept fairly low to get a feel of how the aircraft handled. Suddenly there was complete silence from the engine and the left wing was seen to dip as Squadron Leader Richmond appeared to have some difficulty controlling the now powerless aircraft. Abandoning any attempt to get back to the runway Richmond attempted to land the aircraft on the grass just inside the airfield boundary, some thirty feet of the ground the aircraft was observed to stall and impact the ground pushing both sets of undercarriage through the wings as the aircraft broke up under the force of the impact and burst into flames. Squadron Leader Richmond was thrown clear but grievously injured and burnt. All present were shocked by the turn of events and later investigation would show that the engine had suffered a catastrophic failure of one of the sleeve valves resulting in an instant seizure of the engine. The sudden transfer of torque resulting in the drop of the left wing that was observed by those whatching from the ground was exacerbated by the fact that the now motionless propeller could not be feathered. Though he would eventually recover and be lauded as a member of the ‘Guinea Pig Club’ Squadron leader Richmond would never fly again. James Baker was greatly shaken by this near fatal accident and the horrific injuries suffered by a pilot both he and Valentine admired and knew so well. This shocking event would result in James Baker starting research on a number of technical issues that would greatly influence future aviation but that is another story.
One immediate effect of this untimely accident was that all Napier Sabre engines were grounded until the accident and its causes hand been thoroughly investigated by Vernon Brown and his air accident investigation team based at the RAE Farnborough. This resulted in all MB’s available resources being put into preparing the Fairey Monarch engine MB4 ready for it’s first flight. Here the added complication of have two sets of instruments for the two halves of the engine with duplicated controls as well’ made for a very congested cockpit and instrument panel. Here James Bakers talents as a designer and his skill at ergonomics came to the fore as he designed a logical and clear layout that formed a horseshoe around the pilot, grouping dials and controls logically by function and consistently arranging the two sets required by the left and right side of the engine in pairs. Later the MB4’s cockpit would be used as an exemplar of how things should be done whilst other aircraft were shown to have cockpit panels laid out as if all the instruments had been hurled into the aircraft willynilly.
The reason for the file now being on Sir Phillips desk was that Valentine Baker had just completed the first series of flight trials in the Fairy Monarch engine MB4. Initial results had shown that the aircraft could achieve four hundred and thirty mph at twenty thousand feet and with development, James Martin was confident that the slight lateral instability experienced by Valentine Baker at high speed could be corrected and a true four hundred knot top speed achieved with an aerodynamically clean aircraft. To that end MB aircraft were requesting permission to complete both the MB 3 and the MB 5 airframes as MB 4’s to expedite the acceptance trials and getting the aircraft ready for series production. Reading the notes there was paragraph summing up a brief design appraisal made by a team from the RAE. They noted that the modular system with a tubular structure with a semi stressed skin permitted large easily remove access panels that facilitated maintenance and servicing the aircraft. They also noted the wide track of the under carriage, fifteen feet two inches on a wing span of thirty five feet. The very good access to the four cannons and the stowage for two hundred and fifty rounds per gun was also noted. Fitting this into the comparatively thin wing of the MB 4 had taken clever design of the ammunition feed system. The overall length of the air craft being also thirty five feet was almost equal to the wingspan and this might be the cause of some lateral stability problems that were becoming apparent as the performance envelope of the aircraft was explored. The immediate solution was to increase the tail fin area and this was being done on the second prototype so as not to delay the service trials on the MB4. Any further developments would need to be accessed once the full service trials had been completed.
Sir Phillip penciled a note that he recommended proceeding with is course of action. Sir Phillip also noted that the first of the North American Mustang aircraft NA-73X had been rolled out just a few days ago in September and flight testing was due to begin. As yet No MB aircraft had been ordered whilst some three hundred and twenty North American Mustangs had been ordered off the drawing board back in April with the first deliveries due in January 1941. If the MB4 was to be available at any date close to that then production was going to need to be expedited, Sir Phillip again made a note to ensure that decisions were made rapidly and the necessary people in both the AM and the MAP were gingered up. Decisions would have to be made now rather than later if this new fighter was to be in service anytime in 1941. In the rush to expand the RAF in the period immediately prior to the war, in order to get new aircraft into service many new types had been ordered directly from the Drawing Board. This was a high risk strategy that Sir Phillip had always opposed, the number of unsuccessful or compromised designs that the RAF had coming into service in 1940 showed the flaws in this system. Now Sir Phillip with Sir Archibald Sinclair as the MAP was determined to get new aircraft into service that were fit for purpose as rapidly as possible. A prime example of this was the De Haviland Mosquito, once the design was proven to be sound and only then was large scale production implemented. So as soon as the MB4 had proved itself then the button could be pushed but much needed to be done to facilitate a rapid build-up of production and as soon as the basic soundness of the design had been proved.
Great stuff!