Detailing the Defiant: Classic Airframes' 1/48 Boulton Paul Defiant By David Batt

Download David Batt's drawings that accompany this article. They are in Adobe Acrobat format and are drawn to 1/48 scale. Approximately 713kb in size.

Usually it’s the bad guys’ machines that receive negative propaganda both during and after a conflict, but that hasn’t been the case with the Boulton Paul Defiant, the RAF’s Battle of Britain turret-armed fighter. When I got into the research of this extensively slandered machine I realised just how wrong the popular pundits have been, and I think the sympathy I was feeling for the type overflowed into my building of Classic Airframes’ multi-media kit.

A Bit of History

The Defiant’s claim to fame was when 264 Sqn recorded the greatest number of kills for no loss in one day - 37, on 29 May 1940 - that have ever been recorded. During the course of May 1940, the period of the fall of France and leading up to Dunkirk, 264 Sqn claimed 67 aircraft destroyed and an unrecorded number damaged against 14 Defiants and seven aircrew lost. This vindicated the theory of the turret-armed bomber destroyer, for most victories were scored against large formations of bombers, in the main Ju-87s and -88s. The secret was that the Defiant had to seize the advantage if it was to succeed, to be used aggressively and be able to choose its opponent.

The greatest risk to the Defiant came when it was attacked by single-engined fighters and 264 Sqn adopted a standard defensive routine; the aircraft immediately formed a circle where they were all covering each others' tails and they descended swiftly in this formation to sea level where they were invulnerable to any attack from below. On 28 May ten of 264 Sqn 's Defiants were bounced by around 30 Me-109s and shot down six of their attackers with the loss of three of their own number.

Many have said this was only because the Luftwaffe found the Defiant unfamiliar, thought it was a Hurricane and flew into the gunner’s sights. Sorry, not so, for a detailed appraisal of the type had appeared in a German magazine in 1939 and a Defiant had force landed almost intact behind the lines during the invasion of Holland. They knew what they were dealing with. There were however from time to time mixed formations of Hurricanes and Defiants, which must have spoiled the day of many a Luftwaffe fighter pilot.

Alas, 141 Sqn (the other day fighter squadron equipped with Defiants) had adopted a different defensive tactic. It appears that they were to fly straight and level in line astern as if they were some sort of aerial battleships, which would have given their gunners a stable platform while they did not have to worry about 'friendly fire' as all the friendly aircraft were in each other's blind spots. Put bluntly, this tactic didn't work and saw the debâcle that coincided with the end of the Defiant's day fighter operations, when on 19 July a formation of nine 141 Sqn aircraft were bounced on their first and only daylight sortie by, once again, 30 Me-109s and seven Defiants were lost against four Me-109s. Even so, one has to admit that given the odds of worse than three-to-one and hamstrung by incorrect tactics the Defiant was far from defenceless.

Later in the war, should members of these two squadrons encounter each other off-duty the result was frequently a brawl, for members of 264 Sqn blamed 141 Sqn for the poor reputation suffered by a favoured aircraft. Such were the contradictory emotions engendered by the Defiant.

Had it remained in the front line day fighter role it’s hardly likely to have shared the success of types like the Spitfire or Hurricane, but when the night blitz began it was the right aircraft at the right time. It had been designed from the outset as a night fighter and reigned as the RAF’s most effective aircraft in this role until the winter of 1942/43 when it the title was taken by the Mosquito.

On to the Model

The overall shape of the kit parts are seen to be extremely accurate when offered up to Pat McCaffrey’s scale drawings from Nexus Publications, with the notable exception of the tailplane. However there are other areas that can be improved. The lines around the engine access panels are very faint compared to mainstream offerings and these were sharpened up with a couple of passes with an engraving tool, while cutting in a couple of auxiliary intakes and outlets also improved the front end a lot. The greatest improvement to the nose was made by correcting the spinner. It’s spot-on as far as length and diameter are concerned but it tapers too sharply for a Mk I Defiant and therefore looks long and pointed, much more like that of a Mk II. A skim of plastic filler bulked it out nicely and it then it was only a few moments work to sand it to its proper shape.

The accompanying drawing shows the correct spinner profile for the Defiant Mk I, plus details of the interior of the rear fuselage. As the lower part of the gun turret is an open framework I thought much of the fuselage interior would be visible in the completed model. I was proved wrong on this, for the only part of the fuselage structure that is visible is that part immediately behind and below the gunner’s seat. However, there was some satisfaction in building all this detail in, and it can still be viewed by lifting the turret out of the model.

The hinge lines for all the control surfaces are also very faint and I spent some time deepening the lines and scraping them to get the effect of a rounded leading edge to the ailerons and rudder.

Correcting the tailplane

Comparing the aircraft with the plan showed that the tailplane and elevator was correct in span but was too short in chord at the root and had a noticeable triangular planform compared to the original’s emphatic diamond shape. To be fair the shortness in chord is only a matter of 1.5mm or thereabouts, but it does put the leading edge root in the wrong place relative to the base of the fin. However, thanks to the lovely easy-to-work plastic that Classic Airframes use it’s very easy to correct, and I made a start by separating the elevators from the tailplane along the kit’s moulded hinge line.

A wedge of plastic card was glued to the back of the tailplane section, 1.5mm wide at the root and tapering away to nothing at the tip (i.e., the aerodynamic balance’s inner edge) and the elevator then glued back in place. The entire tailplane was covered in filler and sanded smooth before new panel and hinge lines were scribed in. Measuring back from the leading edge, the new hinge line’s inner end starts 19.5mm back and the outer 7.5mm back. The line of both inner and outer edges are correct, so the aerodynamic balance correctly ends up larger than it was.

Considerable care has to be taken to work the tailplane roots to the correct angle, working from the rearmost point to allow for rudder movement, and then the tailplane halves may be fitted as normal with the roots faired in with filler in the time-honoured fashion.In addition to the drooped elevators I intended to animate the model with dropped flaps, extended crew step and opened canopies, so some surgery was needed on the wing. Making the flaps was straightforward with plastic card, though adding the external linkages to the flaps from plastic rod was an unusual chore. These were a distinctive feature and can be clearly seen in the accompanying photo, along with the additional detail I’d added to the undercarriage wells.

Another photo shows the undercarriage in detail with the correct arrangement of the undercarriage linkages, for they’re shown upside down in the kit’s instructions, and also how the oleos have been shortened by some 1.5mm to correct the model’s ‘sit’.

Detailing the Gun Turret

I then moved on to what for me was the focal point of the Defiant, the Boulton Paul A Type II turret. When I first checked out the parts the indifferent detailing in this area almost put the kit onto the "permanently pending" pile, but in some way this initial rejection turned into a morbid fascination. I found myself making personal contact with both the Boulton Paul and the Air Gunners’ Associations, and ferreting out over-specialised books and plans on gun turrets. I even got my hands on a loaned copy of the original working drawings for the Type A turret. The result was my own scale plan of a Type II turret and eventually some cold-cure silicone moulds for the basic turret parts.

The drawings are shown here. Annotations are as follows; M - ammo belts, N - spent case bags, O - magazines, P - hydraulic motor, Q - oxygen cylinder, R - electric motor, S - gun elevating ram, T - seat, U - gunsight, V - turret control handgrip (just like a computer game!), W - high/low speed selector, X - footrests, Y - movable armour plate (between gun mountings).

This work did turn out to be valid, for when the model is displayed with the turret’s doors opened the interior is clearly visible. The only kit parts that were used were the guns themselves with their air shields and the clear cupola, while the seat was cut down to an accurate shape. The rest was from home-cast resin, plastic rod and tube, and stretched sprue.

One feature to note is the way in which the retractable rear decking has been dropped with the turret turned to the right, for this is how Defiants would often be parked prior to the aircrew boarding the aircraft. There is an access hatch in the underside of the fuselage but this would rarely be used by the gunner except in the event of the aircraft turning over. It was more commonly employed by the armourers when they were feeding belts of ammunition into the turret magazines, at which time the turret would be traversed to face front and the fairing would have automatically raised. The retractable foot step is shown on the detail drawings, and please note that this is only my interpretation of the foot step, which I have only ever seen in contemporary photos. One other addition was the pitot head on the port wing, a fairly major item that is somehow omitted from the kit.

I specifically wanted to build a Battle of Britain aircraft so was delighted with the kit’s decal choice, the 264 Sqn aircraft ‘owned’ by the CO, Sqn Ldr Phillip Hunter. I used Xtracolor paints throughout, beginning with the undersides sprayed X-7 RAF Sky. Masking tape was used to get a hard demarcation before the uppersurface colours were added; X-2 Dark Earth and X-1 Dark Green, these colours being masked with my favourite method of paper masks held in place with tiny pieces of Blu-Tack to get a random mixture of hard and slightly soft demarcations.

I’ve heard some comments that the model looks too clean for a combat aircraft during the Battle of Britain, but take my word for it that contemporary photos show it was kept in a very spruce condition. I therefore restricted my weathering to a few paint chips around the access panels, wing roots and entry steps, plus just a hint of exhaust staining. Weatherers can take heart in that there were a couple of 264 Defiants that were very heavily weathered (for examples -S and -T) which would only involve a change in individual letter and serial number.

I’d love the chance to build a night fighter Defiant, but will wait until some courageous resin manufacturer turns up with a Merlin XX nose and larger rudder, not to mention some AI radar aerials, so that a proper NF Mk II can be built. 

Note: An in-depth account (nearly 8,000 words and 27 photos!) of this model’s construction first appeared in the January and February 1997 issues of Scale Aviation Modeller International.