A bit of an F.155T theme developing

[kitbasher]

De Havilland DH117 Viper F.1

The Subject
Specification F.155T was raised in 1955 for a long-range, highly advanced all-weather interception system capable of destroying very high-altitude enemy raiders operating at 60,000ft and Mach 1.3.  All of the major British aircraft companies submitted designs and these are no strangers to this and other modelling forums, being described in (for example) Tony Buttler in 'British Secret Projects: Jet Fighters since 1950'.  I suggest Dan Sharp's 2019 'bookazine' 'RAF Secret Jets of Cold War Britain' and the more detailed book 'Cold War Interceptor: The RAF's F.155T/O.R. 329 Fighter Projects' generated further awareness and interest in the designs.

De Havilland submitted the DH.117, to be powered by two Gyron Junior turbojets and a Spectre booster rocket in the tail, with a crew of two seated in tandem.  Provision was made for a pair of their Blue Jay missiles (which would lead to Red Top), although de Havilland did include a drawing showing the 117 with wingtip-mounted Red Hebes.


de Havilland Viper F.1 XN730 'J', 64 Squadron RAF Coltishall, June 1963

The Kit
Alistair Reid (aka this forum's Lost Cosmonauts) has under the Gannet Scale Models banner released several 1/72 3D-printed kits of F.155T designs, with plans to release more.  A number have already appeared on this forum, including The Wooksta's fleet of English Electric P.8s that debuted at last year's SMW.  I've invested in a P.8 myself (still some way off completion), so when Alistair asked if I'd be up to test build the 117 I jumped at the chance!.

First impressions?  The DH117 is actually a hefty beast.  A fraction longer than an F-101B in 1/72 (in fact not much shorter than a Canberra), but rather smaller than an F-89 in span.  I mention both given that I've long thought the 117 seemed a rather pedestrian design, a bit like a hi-tech Scorpion or a lo-tech Voodoo.

Printed in a mix of clear and white resins, parts breakdown is extremely logical, pointing towards a straightforward build.  Unlike the earlier P.8's integrally-moulded undercarriage and doors, the 117 (and I believe a couple of the other subsequent kits) features separate items.  This is for me a very positive development, a great aid to the PSR work needed as risk of u/c breakage is significantly reduced plus it makes the 'wheels up' option so much easier.

The material used and the quality of the print itself - and I may be imagining this - seems noticeably more refined than the earlier P8 kit.  But treat the resin with respect – it's very hard and can take a lot of 'preparation punishment' but can break if mishandled.



The Build
Parts were carefully removed from the 'sprues', then just as carefully washed in soapy water and allowed to thoroughly air dry.  The kit parts need to be thoroughly prepared prior to assembly.  I used a variety of sanding sticks, sanding pads and wet & dry paper, all wet.  A lot of rubbing down of was needed in places to get the surfaces smooth.  The parts' mating surfaces also need to be thoroughly rubbed flat to minimise joins and further PSR.

I'd previously scaled up to 1/72 some of the 117 plans featured in the Sharp bookazine.  Matching kit parts to these threw up no surprises, although the cockpit canopy part appeared a shade too narrow - by about 1.5 mm either side - certainly not wide enough to allow for an ejection seat to be fitted into the cockpit (or indeed to vacate it!).  Certainly not as wide as a Hobbycraft CF-105 canopy, or a Fujimi Phantom canopy.  This was fed back to Alistair – one of my almost daily progress updates to him – and he's going to widen the canopy accordingly.

In my haste I fitted the canopy to the forward fuselage part before considering nose ballast, d'oh!  Ther forward fuselage part features slots and holes to facilitate attachment to the mid-fuselage part, so a combination of Liquid Gravity and nails plus superglue were passed the through the holes and allowed to set.  I probably overdid the ballast but of course now had no way of checking until the build was almost done, so my advice (again fed back to Alistair) is to leave the canopy off until the rest of the build is done, add as much balance as necessary and then attach the canopy.

The integrally-moulded tailplanes were slightly warped, so needed some hot water treatment to get them straightened out.  Alistair will be looking to amend the printing process to reduce/remove the chance of this and additionally to better define rudder and elevator hinge lines.



Preparation of the mating surfaces of the middle and aft fuselage sections was pretty quick.  The centre section may look as though it doesn't matter which way round it could be fitted, but it does - the end with the two small holes in the engine nacelles attaches to the nose section.  The forward fuselage part is best fitted after the intake interiors are painted.  I struggled to get the rear jointing surface to mate up properly with the front surface of the mid-fuselage section.  In the end I reached an acceptable state, Gorilla Glued it into place and inserted small shims of extremely thin plastic sheet to make up the gaps.  Once dry, these were flooded with medium Zap-a-Gap and left to cure overnight. 

The wings are cleverly designed to slot into the fuselage - much easier than the tab/slot arrangement on the P8 – and allow for a positive fit that aids and abets accurate alignment of the wings.  One can't go wrong with the wings – the anhedral is very evident (as is the wing root training edge fairing into the fuselage) but do dry fit prior to fixing to avoid inadvertent dihedral!  Also scribe/rescribe aileron/flap lines to taste but do this slowly and gently to avoid damaging the fine trailing edges.  I learnt the hard way!  I've recommended to Alistair that the wings are fitted and that joints are filled/sanded prior to fitting the undercarriage to reduce risk of breaking the u/c legs. 

Once the fuselage and the wings were well and truly set, I selected the wingtip tanks over the Red Hebes that are included in the kit (a pair of underwing drop tanks is also included).  At this point I began to deviate from an otherwise OOB build by fitting a pair of pylons from an Airfix Hunter and the launch rails from a PP Aeroparts Firestreak/Red Top missile set, as I'd decided to finish the kit as an 'in service' machine.  The kit includes a pair of Blue Jays but these have been worked off F.155T brochure images and measure out at a scale 8' 9" (ish).  Resultant Firestreak and Red Top (via Blue Vesta) missiles were 10' 6" and 10' 9" respectively, so aftermarket Firestreaks were used.  The kit's Blue Jays won't go to waste, though.

I found the wing joints around the leading/trailing edges a bit of a fiddle to clean up.  Nothing a bit of care and various files couldn't resolve, but I feel it would have been easier if the wing root slot (and corresponding wing 'mounting block' been extended forward and aft by around 5mm.  That would also reduce the risk of not damaging the fine wing leading and trailing edges.



Once I was happy that no more PSR was needed I attached the nose and undercarriage parts.  All fitted snugly with minimal filler needed around the nosewheel but some noticeable gaps around the main u/c items (the nosewheel doors were fitted at this stage, the main u/c doors being left off until after painting and decaling).  Once all sorted out I began the painting process.

I elected to go for Dark Sea Grey/Dark Green uppers and High Speed Silver undersides, more or less following the pattern in the Sharp book.  That then would put the finished model in the early 1960s - Light Aircraft Grey replacing High Speed Silver around 1965.  Initial priming with Humbrol 56 Aluminium was allowed to thoroughly dry before a thorough but gentle all over rubdown of the model with very fine wet and dry cloth and more primer applied.  Once happy, base coats of Humbrol Dark Sea Grey and Dark Green were applied ahead of Xtracolor topcoats of the same colours.  A couple of coats of Xtracolor High Speed Silver were applied to the undersides.  Main u/c doors were prepainted at this point.



Like most of the F.155T designs, the canopy was heavily framed; I can't help but feel that 'in service' F.155Ts would have acquired clearer canopies so in a further departure form the 'actual' 117 I masked what I decided would be 'in service' canopy frames and applied a mix of blue, silver and grey paint to represent the canopy.

Once dry, markings were applied.  These were a mix of Modeldecals: sheet 47 roundels and fin flash stripes (I used a Lightning F.2A item as my fin flash template), 64 Sqn Phantom markings and selected stencils from sheet 30 and serials from sheet 23.  XN730 was, btw, actually a Lightning F.2/F.2A.  Only when the decals were properly set were the prepainted main u/c doors and a pair of Red Tops tacked into place for the purposes of some initial 'beauty shots' I wanted to get to Alistair (these have already appeared on FaceBook and Instagram).  For the fully finished model I've used PP Aeroparts white metal/etched brass Firestreaks (and of course glued the u/c doors).


earlier 'beauty shot' with tacked on Red Tops

Overall, a very straightforward build.  Yes, a kit for an experienced modeller but average modelling skills such as mine will see you through the build process with no major challenges.  Treat the resin with patience and respect and your efforts will be rewarded.  One unforeseen bonus is that I'm less daunted by the P.8 – work on it has resumed – and I look forward to my next Gannet Scale Models kit.

Having now built the 117 I now think it's more of a cross between the F-89 and the F-101B, and not an 'F-104 on steroids' as some say.  There's an interesting DH117 thread on the Secret Projects forum that includes an overlay of a 1/48 X-3 over a 1/72 DH117 and there are a lot of similarities in the basic shape.  And I must say I'm won over by it.  Whilst a conventional design is in fact rather elegant, and if handsome is as handsome does then it could have been a very good
aeroplane.  We'll never know, and whatever one's opinion it's a lot of machine just to get two Blue Jays in the air – much more than the Lightning! – but I'd like to think it had lots of design potential (and a proper name, one leading on from Vampire/Venom/Vixen):
  •   Viper F.1 – two Firestreaks
  •   Viper F.2 – provision for up to four Firestreaks and air-to-air refuelling
  •   Viper F.3 – Viper F.2 upgraded to carry up to four infra-red (IR) Red Tops
  •   Viper F.3A – Viper F.3 upgraded to carry up to four IR or radar-guided Red Tops (or a mix of these).
  •   Viper F.4 – 'Super Viper' with Spey engines, Westinghouse AN/AWG-10 radar in a shortened radome, redesigned larger wing, provision for four Sidewinder and two Sparrow missiles.

[Tophe]

Good!

[PR19_Kit]

A very 'sharp' looking machine Dave, in more ways than one. 

It doesn't give you a sense of its size in the pics, but if it's almost as long as a Canberra that's one BIG aeroplane!

Nice one. 

[The Wooksta!]

It's alreet, I s'pose...

Light Aircraft Grey - the Lightnings never got it until the grey era, as the Grey/Green ones still had the Aluminium underneath.  Serial?  Lightnings were ordered and serials issued for the F2 by the time the effects of the Sandystorm hit, so codes from F3 could be available.  Me, I'm just nicking a Phantom one.

I think mine will be the F4, as it's got in IFR probe and the (still to be fitted) pylons.  I'll be nicking the Red Tops from the Sword Lightning T-Birds as the fins are separate - photos of Lightnings in the 80s show finless missiles, as they were removed to reduce stress.  May do them as green acquisition rounds though.

[kitbasher]

Thanks for your comments, lads.

Light Aircraft Grey replaced High Speed Silver on painted undersides.  Transport aircraft such as the Comet, VC10, Belfast and Argosy were updated, I think even Pioneers and Twin Pioneers.  Not sure about transport helicopters.

Most camouflaged Canberras had their repainted but IIRC some of the B(I)8 fleet didn't.

Dark Sea Grey/Dark Green Lightnings F3/T5/F6 always had natural metal undersides (never painted), as did the F2As that ended up with Dark Green uppers.  I think T4s may have been the same but not certain whether T4s got DSG/DG uppers, but Germany T4s did get DG uppers.

As you say, Lee, they got LAG as the grey schemes were applied.  Looking forward to your Viper F4, btw.  I've my own idea for an F4, but don't hold your breath!

[The Wooksta!]

Really should pull me finger out and get cracking with mine, but the mojo has gone on a business trip elsewhere and my mind is currently occupied with a train derailment and aftermath in West Europ Dome.

[Wardukw]

I like large single seat fighters and this one is a very nice one 
The nose and front part of the canopy look like F4 and i like the F4 so thats a like right there..even if it aint still a like  ..its a simlier idea im gonna do to a B58 .

[Lost Cosmonauts]

Thanks for taking on the test build and giving feedback throughout - all led to an excellent result.

[kitbasher]

I like large single seat fighters and this one is a very nice one 
The nose and front part of the canopy look like F4 and i like the F4 so thats a like right there..even if it aint still a like  ..its a simlier idea im gonna do to a B58 .

The burner cans remind me of Spey Phantom afterburners, hence the 'Viper F.4' description.

[Wardukw]

Yeah Dave after taking a better look at the cans there is F4 in there for sure ..another like 
I am surprised that the wings are so straight with a mild taper to the leading edge ..would have thought for very high speed flight the wings would have more sweep to them ..like  a F4s for example and would also produce less drag.

[kitbasher]

Yeah Dave after taking a better look at the cans there is F4 in there for sure ..another like 
I am surprised that the wings are so straight with a mild taper to the leading edge ..would have thought for very high speed flight the wings would have more sweep to them ..like  a F4s for example and would also produce less drag.

I think the wing plan is what prompts comparisons with the F-104 and to a lesser extent the X-3.

[The Wooksta!]

I like large single seat fighters and this one is a very nice one 
The nose and front part of the canopy look like F4 and i like the F4 so thats a like right there..even if it aint still a like  ..its a simlier idea im gonna do to a B58 .

The burner cans remind me of Spey Phantom afterburners, hence the 'Viper F.4' description.

I used a spare set of Tornado burner cans to busy mine up.

[NARSES2]

Come out really well Dave 

[Glenn Gilbertson]

Maybe a pedestrian design for a fighter, but a very elegant model!

[Wardukw]

Yeah Dave after taking a better look at the cans there is F4 in there for sure ..another like 
I am surprised that the wings are so straight with a mild taper to the leading edge ..would have thought for very high speed flight the wings would have more sweep to them ..like  a F4s for example and would also produce less drag.

I think the wing plan is what prompts comparisons with the F-104 and to a lesser extent the X-3.

Oh theres F104 in there for sure ..admittedly a crap load larger 
Sticking to that wing (this is what id done ..but thats me  ) id angle them down ..giving them a F104 look and we both know how fast that missles with a man in it was ..yours woulď be probably as fast with its monster engines 

Lee that would have blinged the hell out of it mate.
If i was gonna go nuts on that kit id have hunted down some AM burners like F15 or F4 .fully detailed jobbies .