A Pair of Two-Seater Spitfires

[kitnut617]

Some time ago, Greg posted this profile of a Two-Seater Spitfire.  I thought I would give it a go ---

[kitnut617]

But things didn't go to plan ---

[kitnut617]

Greg's profile shows it to be a trainer and have two ejection seats, but in the space as shown I couldn't get it to work.  For the yellow Spitfire I reverted back to regular seats and then tried to get them in place with a fair bit of room for each cockpit.  I found if I used the same reasoning as I used on my Seafire (Hybrid) Mk.45 build, that was to raise the seat by 6-8 inches, I could make something to work.

First though I built up a couple of cockpits, one was from a 'low-back' Spitfire and the other was from a regular fuselage Spitfire.  This was to determine how much room I would need for the project.  I found that if I moved the front cockpit forward as far as it would go (in real life that is) I only had to move the rear cockpit a short distance backwards and upwards.

However, I then had to reason as to where the displaced main fuel tanks would go.  The answers came fairly easily.

Quite a large tank could be placed under the rear cockpit, and the wings I used are from an XtraKit Mk.22 which already have quite large leading edge wing tanks engraved so there was almost all the tankage recovered, but I've taken it a bit further.  The story behind these two builds stems from preparations for the Tiger Force operation in the Pacific, so for training I needed a Spitfire which could fly for long distances.  I also thought that the latest equipment would have been used so I've gone with a Mk.21 as a base.

[kitnut617]

The biggest problem I had was to find a canopy that would fit, searching through my spares box of clear plastic I found a long thin canopy which I just could not identify.  But because all the spare stuff are left-overs from models I built it had to have been from one of them.  It turned out to be from an OA-4M Skyhawk but as it is it was way too long.  Plus I wanted to have a rounded profile to the top of the canopy.

What I did was cut about 4mm out of the center, then filed the rear end so I had a vertical finish, then filed the underside of the windshield so it would match the Spitfire's fuselage.  Then I hit a snag, I buggered it up ------ a huge crack appeared half way up one side and went horizontally backwards which you can see in this pic below.  You can see here I've built up the rear fuselage even more than what a regular fuselage is. It's about 2mm higher at the end of the canopy, this is to accommodate the raised rear seat.  Also you can see how much the front cockpit has been moved forward by the gap under the center of the canopy

[kitnut617]

The model is a mish-mash of different Spitfire kits though, fuselage, prop/spinner and one cockpit is from the Academy Mk.XIVc kit (1/72 scale of course  ), the wings, tailplane, u/c, front cockpit and airfilter are from an XtraKit Mk.22, then some combat tanks and enlarge rudder come from a Special Hobby Mk.24 kit (there's a pile of spare parts in this kit BTW)

[kitnut617]

Anyway, a request on the forum for another canopy was answered by both Evan and Carl, the one I got from Carl went on this one, the one from Evan is on the black Spitfire (actually it's Humbrol 181 Sea Blue).

In these pics you can see that there's plenty of room in the cockpit, and also the new canopy from Carl.  This was also shortened the same way I originally done the other one only refined it a bit.

In the top pic you can see behind the rear seat some styrene card, I put this there so that I could scribe onto it the rear shape of the canopy which I then filed down too.  I then massaged the fuselage side plastic so it would match the bottom rail of the canopy, then I filled in behind the styrene card with putty which was sanded down to the new rear fuselage shape.  I've read in the Morgan & Shacklady book that changing the top side shapes and profile of the fuselage was a regular accurance so this would fall under the same reasoning.

[kitnut617]

So I'm going to call the yellow Spitfire a T.Mk.21.  They would have been converted in Canada by Canadian Vickers and issued to some of the training bases that littered the Prairies providing up-to-date training for operations in the Pacific (I've read recently that Canadian squadrons had already been transitioning back across the Atlantic before the end of the European phase of the war had finished and were trainig-up for operations in the Pacific, though mostly these were bomber ones but I could see fighter ones doing it too if the war had continued).

Another pic of the T Mk.21

[Jeffry Fontaine]

Robert, you always manage to come up with some amazing models no matter how difficult the path was to get to the point to show us mere mortals what can be done with some imagination and ingenuity.  You claim mistakes were made but the end result is a rather nice looking two-seat late mark Spitfire training aircraft.  The other two-seat/two engine Spitfire is also looking quite promising. 

There is one question I would ask.  What about an increase in the rear control surfaces to compensate for the new canopy and fuselage changes?  Would the existing surfaces be sufficient for the modifications? 

As always, keep up the most excellent and exacting work! 

[kitnut617]

There is one question I would ask.  What about an increase in the rear control surfaces to compensate for the new canopy and fuselage changes?  Would the existing surfaces be sufficient for the modifications? 

Thanks Jeff --

On the trainer, I've gone with the enlarged Spiteful type tailplane from the XtraKit box and in the Special Hobby Mk.24 box there are about 6 different rudders, a few of them are for a Seafire variant.  But there is one very large rudder which I've used for the trainer, I really should say a much broader rudder which I can't really say what it's for, because it's not the rudder the instructions say to use for the Mk.24.  It could possibly be for a Mk.XVIII which I know had a much broader type.

For the Double-Spit (build story coming soon), I haven't quite made up my mind if the fin needs to be bigger, they're both Spiteful type fin/rudders.  If it does I'll have a look through the Morgan & Shacklady book to see if there's something I could copy, but I don't really like what they came up with for the Spitfire Mk.23

[Brian da Basher]

Wow that's some fantastic and incredibly well-thought out work, kitnut!

The yellow one, from the side view, reminds me of a Scottish Aviation Bulldog trainer a little.

I've got to commend you for taking on all that work on the 'pit and it sure paid dividends!

Brian da Basher

[kitnut617]

Not long after I got the trainer to the stage you see in the pics, the canopy Evan sent arrived.  So I got to thinking just how could I make a two-seat Spitfire have ejection seats and look right too.  Now I've had something on my mind for quite a while, I've always wanted to have a go at a Twin-something or other, and here was an opportunity because all of a sudden I had a spare Spitfire Mk.22 fuselage. And recently I bought about half a dozen XtraKit Mk.22's because they were going really cheap at Hannants (6 for C$45) just for what-iffing.

The first thing I did was to sort out the cockpit, I decided to use Martin Baker Mk.4 seats in the version I was going to build (a NF Mk.28) but quickly found out that a much longer space would be needed than the trainer has.  This was to accommodate the radar control panels etc plus the much larger seat area.  I did the same thing as the trainer by moving the front cockpit way forward but I had to cut much too much out of the rear end so the only solution I could come up with was to stretch the rear fuselage out some, which I did, about 9mm (24").  This played into my design because it now looks more in proportion.

Once the cockpit was sorted I then turned to the center wing section, for this all I did was to cut the kits bottom wing part right down the fuselage center to make two separate wings, then scratch built a new center section using various types of styrene strip and card.  One thing I decided to do was to give it wing leading edge radiators because having built quite a few Spitfires over the years, it always struck me as being really sleek looking aircraft without the underslung radiators.  So having a few sets of Tempest Mk.I conversions I decided to use one of them here.

In the pics below, you can see where I went about cutting and adding styrene and you can also see what I did with the other fuselage ---- I've since refined this from what you see here, but I taped it together just so I could get a visual on it.

[kitnut617]

So this is the idea behind this one:

It's going to be a dedicated post-WWII nightfighter and the story will go along that it was a rushed 'stop-gap' solution to fill in after the sudden and unexpected demise of the Mosquito which was much sooner than what the RAF had planned.  It evolved from a Supermarine project that was proposed to the RAF for their 1944 Very Long Range Fighter spec (for Tiger Force) which was eventually awarded to the De Havilland Hornet.

As you can see it has a crew of two in the port fuselage and a pair of heavy cannon in the starboard fuselage (30mm Hispano for this story).  You can see them just protruding out along the top of the fuselage.  These cannon are operated similarly to how the Germans had their "Schrage Musik" and was adopted by the RAF after the captured equipment had been thoroughly tested.  Supermarines design had them depressed into streamlined channels and they could be elevated into one of a couple of pre-set positions moments before the actual attack would happen.  One position would have the line of fire just clearing the prop diameter, and then another at it's highest position, about 45 degrees (they could not be fired straight ahead though, that was for the wing cannon, which comprised of one Hispano 30mm and one short barrelled Hispano 20mm in each outer wing).  This would give the pilot several tactical options for attack, a line astern attack, slight below and almost below.

Below are some pics of where I've steadily refined the idea,  I've had to change the canopy slightly because once I got the pilots onto their seats I needed a bit more room (bottom pic).  I've gone with 50's style figures for the pilots (from the new Airfix F-86 kit kindly provided by Lance [lancer] on the What-If Forum)

[kitnut617]

Wow that's some fantastic and incredibly well-thought out work, kitnut!

The yellow one, from the side view, reminds me of a Scottish Aviation Bulldog trainer a little.

I've got to commend you for taking on all that work on the 'pit and it sure paid dividends!

Brian da Basher

Thanks BdB ---

[Camthalion]

they are really cool.  Fantastic work.

[kitnut617]

they are really cool.  Fantastic work.

Thanks --

[Jeffry Fontaine]

Robert, is there going to be any "signature" radar pod or antennae affixed to your twin-engine Spitfire to suggest a night fighter/interceptor role? 

[kitnut617]

Because the wing leading edge radiators protrude further out (by about 3mm), I thought that this was a good opportunity to have a revised airfoil for the center section.  In the top view pic a couple posts above, you'll notice that I've extended the trailing edge further back than what the outer wings have by about 4mm.  This created a problem on how to blend in the wing root fairing, but the answer proved easier than expected.  I just moved the wing root fairing back 4mm too ----

But after looking at the result for a while I didn't quite like the look of it.  So I've modified the trailing edge of the outer wings (at least on the port side for the moment).   I was told sometime ago by John Adams (of Aeroclub fame) that when aircraft are drawn up, the leading and trailing edge lines were always extended through to the center line of the fuselage and this is where the dimensions were always taken to.  So what I did was glue some styrene strip to the trailing edge of the outer wing from just where there's a little fairing on the aileron trim tab back to the wing root fairing, then using a ruler which I lined up on the trailing edge of the center section, I drew a line to the fuselage center line. After that I used a Spitfire Mk.I wing as a pattern (like a French Curve) and traced a line on the styrene from this center line intersection back to the little fairing on the trim tab.  What this did was broaden the wing at the wing root by 2mm which meant I had to move the wing root fairing back 2mm to.  In this pic below you can see the result ---

[kitnut617]

Robert, is there going to be any "signature" radar pod or antennae affixed to your twin-engine Spitfire to suggest a night fighter/interceptor role?

Absolutely Jeff, but not that honking great big thing that the F-82 got --- 

Sometime ago I tried to make some 200 Gal Mosquito tanks and my first attempt came out a bit small.  I stored that one away for another time and this seems to be a good time to use it.  Here's some pics of it and the last one showing it sitting on top of the wing to give you a size perspective.  Of course it will eventually go on the bottom of the wing.

[Jeffry Fontaine]

The "Long Dong" pod used on the F-82 for the AN/APG28 (F-82F) and SCR-720C18 (F-82G) was certainly obscene but it served the purpose to get the antenna ahead of the propellers and away from any possible interference. 

[kitnut617]

I gave that some thought Jeff, but my thinking is that the Rotol contra prop I'm using for this project are made of wood, composite wood yes, but wood all the same (Freightdog's Seafire 46 conversion), so from what I've read wouldn't effect too much that couldn't be compensated for.  Of course the blades could also be made from fibreglass or something like that.  Plastics were beginning to be used in a lot of things at the end of WW.II, my 'Aircraft of the Fighting Powers' books have all the advertizing for this product in the front pages.

In this pic, you can see how much I've added to the outer trailing edge and also how my u/c will be orientated.  It's my opinion that the only outfit to get a ""twinned"" aircraft right, is North American ---  so I'm following along those line with certain things. 

The u/c BTW, is modified Tempest gear --

[kitnut617]

The "Long Dong" pod used on the F-82 for the AN/APG28 (F-82F) and SCR-720C18 (F-82G) was certainly obscene but it served the purpose to get the antenna ahead of the propellers and away from any possible interference.

It should be mentioned that the P-82D was to have APS-4 which was a much smaller radar, something along the lines of the radar used on Hellcats, Corsairs and Fireflys. my Double Spit would have something similar I think, the Brit version 

[kitnut617]

In the Double Spit', I've reversed how the pilots are situated, this is because I'm having the u/c fold away under the fuselage and into the center section, I raised the pilot up to be above the u/c bay while leaving the radar operator at normal seating level.  The canopy shape allows me to do this. The canopy is from a TA-4 Skyhawk and I cut out the middle of it, not quite as much as the trainer canopy though. Then because I knew that the width of the canopy rails are just about the same as a Spitfire bubble canopy, I reasoned that somewhere along the two types of canopy there had to be something in common. And there was --  I carefully filed and sanded each canopy until I got a match, so right at the bulkhead behind the radar operators seat is where the two canopies are glued together.  I got a nice flowing shape to it ---

For the u/c bays, I've used as much of the bit's and bobs that come in the XtraKit box, the internal sides of the bays are all separate pieces.  I've also cut out the top of the bay in the outer wing and repositioned it in the new center section, the cannon bays are now moved into what was the wheel bays and the underslung radiator hole is now all filled in along with the rest of the 'old' u/c bay.  The starboard wing will all be done in a similar fashion once I get all the little details sorted on the port wing.

[FAAMAN]

Excellent concept, great build!!

[kitnut617]

The "Long Dong" pod used on the F-82 for the AN/APG28 (F-82F) and SCR-720C18 (F-82G) was certainly obscene but it served the purpose to get the antenna ahead of the propellers and away from any possible interference.

I had a re-think last night about what you said here Jeff, and I could do it another way.  I could use the pod as what it is, a drop tank, then rob my Airfix Fairey Firefly of it's wing mounted radar pod and fuel tank.  Or I could make a copy of them ----

But there's a precedent out there for doing it the way I planned to do it, I have a Fairey Firefly NF Mk.II conversion in the stash which has two wing leading edge mounted pods, but these are positioned close to the fuselage.  So the radar beam would have to pass through the prop disc and I think these NF Mk.II's had metal prop blades, but I could be wrong   ---

Top pic shows the conversion I have.  Bottom pic is of a NF Mk.I, you might notice that the operating date for this one is 1948-49, right in my project time line.

[kitnut617]

Excellent concept, great build!!

Thanks mate !

[kitnut617]

On the underside view in reply#20 you can see I've taped a Seafire FR.47 style air intake onto the port fuselage, this comes from the Special Hobby FR.47 kit and I'll make a copy of it because apart from the use of it on this project, I've got a number of other projects I could use one on.  I've enhanced it a bit by digging out the hole for the air intake ---

Reading the 'big' book (Morgan/Shacklady), there's photos in there showing that Supermarine trialed this intake on a number of other Griffon engined Spitfires, one of my Aeroclub Mk.XVIII's will get the treatment   

For what it's worth, there's no aftermarket product of this in 1/72 scale, got one in 1/48 but that doesn't help me here --- 

[kitnut617]

Another thing you might notice is the odd looking exhaust stubs, that's because they're not exhaust stubs but an exhaust shroud. These were taken from some spare Shackleton cowlings I had left over from another project.  The intention is that they're flame suppressors and the actual exhaust exits out the rear end of them.

[Old Wombat]

Another thing you might notice is the odd looking exhaust stubs, that's because they're not exhaust stubs but an exhaust shroud. These were taken from some spare Shackleton cowlings I had left over from another project.  The intention is that they're flame suppressors and the actual exhaust exits out the rear end of them.

Logical for a nightfighter.

:)

Guy

[ChrisF]

Liking the yellow one and watching the "twin" with great interest ! :)

[kitnut617]

Thanks guys --

[Tophe]

  Wonderful Twin-Spitfire! Belated congratulations!

[kitnut617]

Wonderful Twin-Spitfire! Belated congratulations!

Thanks Tophe,    I had a thought you might like it ---- 

[kitnut617]

After Jeff's observations about the radome installation and doing some thinking about it, I decided to revise the plan.  The large tank will be just that, a large drop tank on the centerline of the wing center section.  I might even go with something bigger too (maybe a modified 300 Gal P-38 tank).  But whatever I use it will be on the center line.  But what about three of those flat F-86 tanks, on the centerline and one just in-board of the cannon bays on each side --- hmm! give that some more thinking I will -----

I've ordered a couple of Hellcat wing radomes and I'll see how these look once they arrive.  It might have just one or I might go with two radomes, or one radome and a tank for the other, I'll have to think up a revision to the back story

[Brian da Basher]

You know, with all that extra engine power, you could put a radar pod on both wing tips. Or not.

I've come to realize that not only is your thinking much better than mine, but so are your talent and skill, kitnut!

I eagerly await your next update!

Brian da Basher

[kitnut617]

I've come to realize that not only is your thinking much better than mine, but so are your talent and skill, kitnut!

Brian da Basher

we need a bigger version of this BdB  ----        But thanks for your kind words

[apophenia]

Your retractable Schräge Musik concept is brilliant!  :)

[kitnut617]

Thanks ap'  my idea with that is the cannon is mounted along the top edge of a laid down drum, the ends of the drum having a bearing and the ammo being stored in the drum. When elevated, the cannon would sort of roll backwards and upwards.  When fired, the empties would be gathered in a bag also in the drum.

[kitnut617]

Making progress  - albeit slowly ---

I've got the wing mods all done, although that didn't go quite to plan.  While trying to save it from dropping onto the floor, I caught it with my legs and promptly broke it in half.  Anyway, all repaired now.

Top two pics show it compared to an F-82 (I've started to do some panel line scribing on the port wing), third pic shows the modified Tempest main u/c, I shortened the legs right down to the minimum and then re-shaped the doors to look more Supermarine.  Last pic shows that I used the Tempest tail wheel too, but because this is a much bigger wheel/leg, I had to move it into an area which could house the u/c bay.  It's still in the tail assembly group, just that it now would mount directly to the tail assembly joint frame instead of being right at the rudder hinge.

[Tophe]

It's great to see the comparison to a P-82 at the same scale, thanks!
And the work you did for the tailplane is amazing (I feel jealous)...

[kitnut617]

Thanks Tophe --

[Camthalion]

It's great to see the comparison to a P-82 at the same scale,

I agree.    Its looking very good

[kitnut617]

Thanks Geoff, 

Well since Jeff (Mr Fontaine) made a comment about enlarging the tail I've been giving it a lot of thought.  Browsing the 'big book' (Morgan/Shacklady), I looked for something that would suggest ""Supermarine"" and found that what they really did was they just made the tail bigger as the Spitfire got developed.  Interestingly though, the rudder hinge position stayed exactly in the same place when measured from the engine bulkhead.  Which sort of posed a problem, the Spiteful tail was the biggest that was developed and is about as big the tail assembly can handle --- and my project has two of them.

But as things happen I've got a plan ---- sometime ago I bought a number of Tempest Mk.I conversions (to be used on another project) and I just happened to notice that the Spiteful fin/rudder sort of matches the profile of the fin/rudder of the Tempest Mk.I.  It's just bigger -----  so playing around with one tail I had already cut off I found with a little bit of re-profiling, I could make the tail look like a Spiteful tail --- just it's bigger ---  see where this is going ---- 

[kitnut617]

It's great to see the comparison to a P-82 at the same scale, thanks!
And the work you did for the tailplane is amazing (I feel jealous)...

FYI:  I did some dimensional checking of various aircraft that I would consider being in the same catagory.
                           Span            Length
NA F-82              51'-3"          38'-3"
DH Hornet          45'-0"         34'-6"
Twin Spitfire       48'-11"       34'-11"

Although the F-82 and Hornet both have 14'-0" from center to center of propellers, I have my Twin Spifire's propellers at 12'-0" center to center.  I did this so that I would have one foot between the blade tips (using a 11'-0" diameter prop), but the Seafire Mk.46 contra-props I'm using are only the 10'-3" diameter ones so it didn't work out quite as expected.

[The Big Gimper]

It's great to see the comparison to a P-82 at the same scale, thanks!
And the work you did for the tailplane is amazing (I feel jealous)...

FYI:  I did some dimensional checking of various aircraft that I would consider being in the same catagory.
                           Span            Length
NA F-82              51'-3"          38'-3"
DH Hornet          45'-0"         34'-6"
Twin Spitfire       48'-11"       34'-11"

Although the F-82 and Hornet both have 14'-0" from center to center of propellers, I have my Twin Spifire's propellers at 12'-0" center to center.

A belated awesome build Robert.

You now have me thinking about a twin Hornet: "Twornet"

[Brian da Basher]

It's great to see the comparison to a P-82 at the same scale,

I agree.    Its looking very good

I've got to agree. Nice progress, kitnut!

You may think you build slow, but you're going at a much faster clip than I am currently.

Already looking forward to more,
Brian da Basher

[kitnut617]

My radome order arrived quite quickly, they're from a Hellcat nightfighter.  Slipping them on the wings I have to admit that it makes the Twin Spit' look quite good so this is how it will go.  I'll use the center hard point for a large drop tank but not like the tank I was going to use as a radome  I've also made progress with the larger fin/rudder, you can see the visible difference between the original and what I've changed.  Lining up the hinge line with what is already there, I then found a corresponding point on the rudder trailing edges that blended in.  This dictated just where the cut lines would be for the match-up.  Some chord thickness thinning of the new fin was needed though  ---

[taiidantomcat]

I am loving this  :)

[Brian da Basher]

I am loving this  :)

You & me both, Mr Tomcat! I especially like the asymmetrical fin & rudder.

Looking great, kitnut!

Brian da Basher

[kitnut617]

I am loving this  :)

You & me both, Mr Tomcat! I especially like the asymmetrical fin & rudder.

Looking great, kitnut!

Brian da Basher

Thanks guys, the tails will look the same  ----- eventually   

[kitnut617]

Bit of an update:

After enhancing a Seafire 47 carburetor intake from a Special Hobby kit, I made a mould of it.  Then made some casting.  Bottom pic is the result, the little bit at the tail end of the fairing will be carefully cut off and glued to the appropriate u/c bay door.

[kitnut617]

And some top view pics and also showing the new tail fin.  Just got to do the other one now and then it's off to the races ---

[Tophe]

  :-*Wow! Wonderful!

[Brian da Basher]

That's some outstanding progress, kitnut!

The contra-props are a fantastic touch!

Brian da Basher

[kitnut617]

Thanks guys, it's taking a while but I'm getting there.  I want to get these two Spitfires done before November, then I can concentrate on the Turbo-prop Sunderland and AV-19 in the 'Clear your Bench' GB

[kitnut617]

Well as things happen, dick-all has happened to any model building this last month or so ----   

But another member has come up with another solution to make a 2-seater, Keith (talleng) has built this marvelous T Mk.22 where he found something more easily to use, a Canadian operated Chipmunk canopy.  It sort of matches Greg's original idea perfectly and I'm going to add a couple more 2-seaters to the build using this canopy.

Here's a pic of Keith' 2-seater which has given me some new ideas ---

[GTX_Admin]

 :)

[Silver Fox]

Fascinating to get the thought process and the build process all at once!

Truly outstanding work, I would never have considered it... but it looks so right that now I have to wonder why. :)

[kitnut617]

Thanks mate!

[Tophe]

Great!