Yokosuka D4Y2 Type 12 Suisei (Comet) ***FINISHED***

[PeterB]

I suppose that like many of you, when I was building kits in the 1960's I had no problem getting Airfix, Revell and Frog kits locally but except for the late 60/early 1970 Frog reboxings of Hasegawa kits, very few Japanese or Italian made kits were on the shelves so I had to resort to mail order. During that period a company called BMW in Wimbledon used to advertise all sorts of “exotic” kits in Airfix Magazine, and so when I happened to get a job interview with Marks and Spencer in Baker St. London in early 1970 I though I would pay BMW a visit – in those days they paid for your trip and put you up in a hotel! This being my first visit to the capital I arrived early on the day before the interview and did a bit of touring about, and the following day, after the interview I took the tube out to Wimbledon.

 

After quite a long walk out past the “All England Tennis Club” I finally found their small “shop” - BMW stood for “Builders Merchants, Wimbledon” and that is exactly what they were, but they had started a sideline in Mail Order kits etc a few years previously. Unlike H.J. Walker (Hackney) Ltd who I used a lot in later years, where Tony had a lot of space on two floors in his parents' Post Office on Homerton High Street, BMW were a bit out of the way and must have had very little passing trade, so the shop was just a small single room stacked with all sorts of kits I had never heard of. I ended up buying a couple, probably both by L S – one was the “Yasukuni” - one of the Ki-67 Hiryu aka Peggys that the JNAF borrowed from the JAAF and used as torpedo bombers, and the other was a D4Y2 “Judy”. After a few years the latter was replaced by the Fujimi kit, which was part built when my wife decided to decorate my work room, and during the move it got smashed when something dropped on it. I eventually got a replacement kit but never built it, and when digging out my Ki-100 for this GB I found it.

In some ways the story of the D4Y resembles that of the Ki-100 in that it started out with a water cooled imline engine - initially one based on the German DB 600G, though after the prototypes a version of the DB 601A was substituted, and later it ended up having to be converted to take a Japanese radial engine, but more on that later. I guess that is why the front end is on a seperate sprue. This will therefore be my third attempt at a D4Y2 and I have also got the D4Y3 which is in need of a good refurbishment so I will do that in parallel. The kit was originally released in 1983 I believe and is pretty basic but it does at least have the makings of a cockpit, so the build will be pretty much OOB.

 

A brief note on Japanese inline engines. The vast majority of Japanese aircraft were powered by home grown air cooled radial engines, but between the wars a few had inlines. The Kawanishi E7K floatplane for example had a Hiro 91 inline with three banks of cylinders in a so called "W" layout rather than the more common twin bank "V" whilst the Kawasaki Ki-10 fighter and Ki-32 light bomber were powered by Ha-9 engines which were licenced built copies of the BMW VI. During the early days several companies had arrangements with German manufacturers to help them with design - Aichi for example submitted several designs which were slightly modified Heinkel aircraft, though as time went by the Japanese content increased though German influence remained for a time. Likewise Kawasaki had an arrangement with Dornier, who actually lent them designer Dr Richard Voght (later of Blohn und Voss) for a while, and of course there was a certain British influence as well as a result of the Sempill Mission. These arrangements probably go some way to explaining the Western view that Japanese planes were just copies of obsolete foreign designs! Aichi eventually got a licence to build the DB 600 engine, but soon switched to the later DB 601, which they produced as their Atsuta, whilst Kawasaki also licence built it as the Ha-40 (later renamed Ha-60 under the joint Army/Navy system). Unfortunately the Japanese aero engine industry was not capable of getting the very close tolerances needed by these long engines and this resulted in lubrication and other problems such as crankshaft failure, and a shortage of parts/raw materials saw the inlines falling from favour.

 

Pete

Edited April 12, 2022 by PeterB

[JOCKNEY]

Great stuff Pete

That's a new one on me, which makes it all the better

Best of luck.

Cheers Pat

[PeterB]

15 hours ago, JOCKNEY said:

Great stuff Pete

That's a new one on me, which makes it all the better

Best of luck.

Cheers Pat

Hi Pat,

Although we have a lot more info on Japanese planes these days there are still quite a few that are not very well known. Just taking the JNAF alone between the start of the war in China and the surrender in 1945 Francillon lists over 40 "major" types though one or two of those never entered service like the A7M Reppu. Quite a lot of the more "obscure" ones should be available in plastic so hopefully they will turn up in this GB - types such as the E16A Paul and F1M Pete floatplanes, J1N Irving recce/night fighter and P1Y Frances fast bomber come to mind. As to the carrier attack planes, everybody has probably heard of the D3A Val and the B5N Kate but after Midway the IJN carrier force sort of faded from the limelight so their replacements such as the D4Y Judy and B6N Jill are not well known even though 2000 and 1200 respectively were built, and as to the even later B7A Grace and the C6N Myrt carrier recce plane they are virtually unknown, and yet all of those four were made by Fujimi and/or Aoshima. Other manufacturers have issued kits of the pre war biplanes which make a nice colourful build, so maybe we will see a few of those. It would also be nice to see some of the planes used over China - for example the single engined day bombers like the Ki-32 Mary and the Ki-30 Ann.

 

Pete

 

 

Edited April 12, 2022 by PeterB

[trickyrich]

Welcome along again Pete, with another great choice.

 

These early Japanese models were really nice, when compared to some of the releases from Europe at the time (though they did go through an odd stage in the 80's).

 

This one looks very much of the era and should go together without any issues, though I wonder how the decals have held up. That said I have decals from japanese models that are over 30 years old and still look to be in good condition.

 

Well good luck with this build as well.

 

Oh and did you get the job at M&S?

 

 

[PeterB]

9 hours ago, trickyrich said:

Welcome along again Pete, with another great choice.

 

These early Japanese models were really nice, when compared to some of the releases from Europe at the time (though they did go through an odd stage in the 80's).

 

This one looks very much of the era and should go together without any issues, though I wonder how the decals have held up. That said I have decals from japanese models that are over 30 years old and still look to be in good condition.

 

Well good luck with this build as well.

 

Oh and did you get the job at M&S?

 

 

Hi Rich,

 

I have 2 sets of decs as I kept the bits and pieces from the one I had half built which got broken, but I will give them a coat of Liquid Decal Film as a precaution. Only the Hinomarus and a tail code anyway. As to the job, I am not sure exactly why I applied for it as an Engineering graduate, but it might be because I had put on a fashion show at Uni for some M&S trainee executives and they said they were enjoying the work. I was not too disappointed when they did not offer me a job as my sights were mainly set on the aircraft and motor industries. In the end the only offer I got was from ICI and I decided to stay on and do a Masters, but found it hard going and ended up working in a bank!

 

Whilst waiting for some paint to dry I had a think about my Japanese WWII kits and decided I had built 49 over the years since Airfix released their original Zero. Many of those have been replaced but I still have 27 excluding the 2 or maybe 3 I will attempt in this GB, covering all the various types I have ever built bar the E17A floatplane by Aoshima which seems to have been scrapped at some point. Whilst these cover most of the better know combat aircraft there are still a few missing and that does not include Transport and Trainers plus a whole load of minor types, many left over from the war in China. In fact, although I have a lot more Luftwaffe models they amount to about the same number of types as the Japanese ones I have built, the difference being mostly due to all the variants of the Bf109/110 and Fw190. This GB clearly covers an awful lot of potential planes, let alone anything else ( for example I have a whole fleet of over 40 1/700 IJN warships but I am not building any more) so you could be a busy host!

 

Cheers

 

Pete

Edited April 13, 2022 by PeterB

[PeterB]

As I am going to have my JNAF paints out I am going to refurbish a couple of kits in parallel with the D4Y2, though they will not actually be in the GB.

I have stripped them down with oven cleaner spray and now need to do a bit of cleaning up. On the right is the radial engined D4Y3 and on the left the Nakajima 14 Shi (they seemed to stop using type numbers after year 2/1942) Navy Carrier Attack Bomber Tenzan (Heavenly Mountain) Model II known to the allies as Jill. This aircraft was accepted as a replacement for the B5N Kate before the war started but development was protracted and it did not enter service until early 1943. This particular kit is of the first production version the B6N1 which Nakajima chose to power with their own new NK7A Mamoru engine against the wishes of the Navy who wanted the Mitsubishi MK4T Kasei - Nakajima said it had better fuel consumption and more development potential, but only 133 were built as the Navy then insisted Nakajima dropped the Mamoru to concentrate on their other engines. The main production model was therefore the B6N2 Model 12/12a with the Kasei, which is what I had meant to buy! Fuijimi went through a phase of moulding IJNAF planes such as the D3A, D4Y, B6N, B7A and C6N each in several variants which was useful for the modeller.

 

Pete

Edited April 15, 2022 by PeterB

[PeterB]

Right. I have made a start on the cockpit. So far I have identified 5 possible colours that it could be. One is a slightly greyer version of RAF cockpit grey/green, and another a slightly yellower version of US interior green which sometimes is called “Bamboo” Then there may have been an olive green and also a khaki brown verging on light stone, but the one most kit manufacturers seem to stipulate is a green/blue colour which was known as Aodake Iro. This was a protective lacquer applied over natural metal so it had a metallic look to it. Pictures of the cockpits of the very few surviving planes do mostly seem to be in this colour but some are more of a lightish green, maybe Bamboo whilst some seem to be patchy with both the blue/green and another green. I would not have thought it would have been the most restful colour for a cockpit. Incidentally Volume 6 of Scale Aircraft Modelling International ran a series of articles on Japanese wartime paint schemes and they say the blue/green varied between a blue and a "cabbage green" depending on how many coats were applied, and that the more visible parts such as the cockpit were often overpainted with one of the 3 or 4 other colours I mentioned which could explain my comment about the patchy look, where paint has worn off to show the blue/green underneath. I will use the blue/green in the wheel wells but have gone for “Bamboo” in the cockpit. It looks less patchy and greener in real life!

As you can see it is pretty basic, a floor including seats, a stick, and an IP with a few instruments moulded on. The sort of “pole” between the seats is I guess a sighting periscope which looks out through a window in the floor. If any of you have seen the old film Tora Tora Tora you may remember about 2 hours in a flight of “Kates” approaches the Arizona and the chap in the middle seat bends over his periscope and gives the pilot directions. Unfortunately I have no idea how to capture a film clip so here is a still!

He is calling out what sounds something like 'ouzoooo' which I guess is left, right or steady and once he gets what by today's standards is not a very good model in his crosshairs he drops the bomb! Of course the Kate was a topedo/horizontal bomber, with a crew of 3 and the Judy is a dive/horizontal bomber with a crew of 2 and the kit rear seat points to the back where there should be a 7.7mm mg - there is one provided but no hole in the canopy or mention in the instructions - perhaps it could be pivoted round to face the periscope! Actually I have just worked out that the gun is for the D4Y2-S and is meant to be a 20mm cannon which was mounted obliquely upwards for use in the unlikely event it ever managed to get below and slightly behind a B-29!

 

More later.

 

Pete

Edited April 16, 2022 by PeterB

[PeterB]

The fit is not perfect but nothing a small amount of filler can't deal with.

The nose needed a bit of help - they provide a blanking piece at the rear of the intake to stop it being see-through but nothing at the top so I have added a bit of card.

Construction should not take too long!

 

As this type seems none too well known here is a bit of background.

On June 27th 1936 the second prototype of the Heinkel He 118 broke up in mid air whilst being tested against the Ju 87 to choose a new dive bomber for the Luftwaffe. The pilot, Ernst Udet survived but the hopes of Heinkel were wrecked and the Ju 87 won. A number of authors including Green have sided with Heinkel who blamed Udet – it was intended that the propeller pitch would automatically change to coarse in a dive but as Udet was told, that was not linked up on the prototype and he would have to do it manually, which he may have forgotten. Others however point out that the He 118, which looked like a modified He 70 with its elliptical gullwing, could not be dived at greater than 50 degrees whereas the Stuka could dive at 90, which Udet also seems to have forgotten, so although more streamlined than the Ju 87 and faster, the relatively shallow maximum dive angle would probably have doomed it to failure anyway.

 

So what you ask has this got to do with my build. In fact Heinkel got permission to sell another prototype to the Japanese Navy who were very impressed and about to order it when that too disintegrated in flight so they asked the First Naval Air Technical Arsenal at Yokosuka to rework the design into something smaller and better to replace the Aichi D3A Val. They came up with the Yokosuka D4A1 which was to be powered by a licence built DB601A but due to shortages the first 5 prototypes had instead the less powerful DB 600. According to Francillon in the Putnam book on Japanese aircraft of WWII, it was no bigger in wingspan or area that the A6M Zero and therefore did not need folding wings, and it was still able to cram in almost as much fuel as the Val and had an internal bomb bay to take a 500kg bomb. It could reach a speed of 343mph, 80 mph faster than the He 118, with a normal range of 978 miles and a maximum of 2400 miles, presumably with no bomb and extra fuel. Armament was two forwards firing 7.7mm mg in the nose and one 7.92 at the rear, and max bombload was 560kg. The JNAF were impressed and ordered it into production by Aichi, and then the problems started – it developed wing flutter in a dive and the spars started cracking.

 

More next time.

 

Pete

Edited April 18, 2022 by PeterB

[trickyrich]

off to a great start Pete, it's an interesting read on the history of this aircraft.

[PeterB]

The basic airframe is now complete and at the same stage as the one that got smashed years back.

The D3Y3 is at the back for comparison. The nice thing about JNAF camo is that except for the China scheme it is fairly simple and quick. AFAIK, starting in the early 1930's in all over “silver”, either lacquer or just natural metal, they were switching to all over light grey by the end of the decade, except for those given an upper surface scheme of various greens and browns, mostly in China. After Pearl Harbour they started using green over light grey before too long, though some Zero's were painted with a green mottle over the grey, mostly when land based for cover on the ground I suspect. However, one of my sources suggests some land based aircraft had their undersides unpainted, though those such as the Zero which were intended to operate from carriers probably stayed grey – maybe corrosion protection was a consideration. Also, like the Zero and Val, I had thought that all of the single radial engined JNAF machines had the cowlings painted black but it seems that was not the case as both Fujimi and my other sources confirm the D4Y3 did not! The JAAF camo was far more complicated but I have talked about that in my Ki-100 build.

 

So, to complete the story, until the problems encountered when diving were fixed it was decided to use it for recce as the D4Y1-C and a few had just reached the carrier Soryu in time to be sunk at the Battle of Midway. Production of both the D4Y1 and D4Y1-C continued once the wing had been strengthened. Before too long though the lack of crew and fuel tank protection began to result in heavy losses and the recce versions were found not to be fast enough to evade the latest US fighters – both types were shot down in droves in the battles around the Marianas Islands. The improved D4Y2 had a more powerful Atsuta engine and the D4Y2a upgraded the rear firing mg from 7.92 mm to 13 mm, but neither had any armour and together with the recce D4Y2-C and Ca they suffered heavy losses. Like the Ki-61 fighter, shortages of the inline engine, together with their inherent unreliability were made worse by US bombing raids on aircraft plants and so it was decided to fit a more readily available 14 cylinder MK8P Kinsei 62 radial engine, to produce the D4Y3 Model 33 which had similar performance, but by then the design was out of date. Of course there was a rather hopeless night fighter version D4Y2-S and also a Kamikaze version D4Y4, but having shown considerable promise at first, the Suisei was not a great success. Aichi produced 1818 of all versions and the 11th Naval Arsenal at Hiro joined in with a further 215. Unlike the Val and the Ju 87 which had prominent "gate" type dive brakes below the wing, the Judy had 3 small flush mounted brakes in front of each trailing edge flap.

 

So next up is paint.

 

Pete

 

 

[PeterB]

Well I said it was a simple colour scheme!

Bit out of focus but you see what I mean. This rather washed out underside view shows the small window the bomb aimers sight looked out from.

It perhaps also shows why the blue/green paint was not really suitable for visible areas like in the cockpit, at least not without a coat of something less noticeable over it.

 

Pete

[PeterB]

I don't know why but with kits of Japanese planes I always feel I am on the home stretch when I have painted on the yellow leading edge recognition bands, which apparently started to appear in 1943 on both Army and Navy front line planes, presumably to reduce the risk of friendly fire incidents. They seem to vary both in length and width and I don't know if there were any instructions issued on application but I have never seen any - if it had been the Luftwaffe there would have been chapter and verse on size and position!

They are actually more of a chrome yellow. Still a bit of touching up to do as always, but I will be starting on the decs soon. The colour of the Hinomaru's is problematic as it varies betwwen kit manufacturers and AM decal producers - here for example are a couple of sheets from my stock-

On the left some 10 year old Techmod ones and on the right some ancient Microscale ones. Sources suggest the newer ones are closest but maybe a little too light, but in the strong Pacific sun they faded fast to what I have seen described as a pink colour except of course for the ones under the wings. The kit ones are pretty bright but I have only now noticed that the white outer rings are a bit cream so they are in the window to bleach for a few days. Fujimi have provided 4 medium and 2 small Hinomaru, all with white borders but that is open to question. There was a fair bit of local variation but in general the white outers were only used over the darker camo colours, and even then not always as some of the illustrations I have of Judy's only show the fuselage ones with a white ring. If the kit ones don't bleach out I may have to order another sheet which could delay things a bit - mixing kit decs with AM ones seldom works as the colours don't usually match..

 

In terms of bits to add, there remains the prop, spinner, drop tanks, wheel doors, telescopic sight, radio aerial and pitot tube - in other words what these days seem to be known as the "greeblies" for whatever reason!

 

Cheers

 

Pete

Edited April 20, 2022 by PeterB

[trickyrich]

looking good Pete, you're nearly there.

[PeterB]

Bit more progress.

The D4Y2 I am building is the one on the right, with the D4Y3 in the middle and the B6N1 on the left - the second generation of carrier attack aircraft. I would have liked to build a Saiun recce plane as well but prices for that and the big Ruysei torpedo bomber and the Zuiun floatplane on a certain auction site are ridiculous - anything from £25 to £125 plus in many cases huge postage costs from the US or wherever!

 

So a couple more bits of useless hopefully useful info for anybody unfamiliar with Japanese aircraft of WWII.

 

Propellers were initially silver, though the rear surface was often black to reduce glare. This continued well into the war, but at some point a new colour was introduced on the front surfaces and in some cases, particularly on JAAF aircraft, on the rear as well. This was red/brown shade that kit manufacturers sometimes helpfully refer to as “propeller colour” and which is described as being like tea, presumably the main type we drink in the UK and without milk and when I first became aware of this many years ago I used a tin of Teak enamel bought to paint LNER railway coaches. It is perhaps not quite red enough but I have stuck with it until now for consistency. Unfortunately it has expired after 40 years so I have tried Mahogany instead which is certainly more “tea coloured” to my eye but maybe a bit red so I might tone it down slightly.

 

Warning bands on the front of the props were usually two thin parallel lines near the tip – red on silver blades and yellow on the “tea coloured” ones, though sometimes a single thicker one was used, and I have seen pics of planes late in the war where the entire tip was yellow as on British planes. Some aircraft such as the Ki-84 seem to have had a green/grey prop for whatever reason, and there also seems to have been a single short yellow line near the root of the prop in many cases. Spinners were silver with silver props and tea coloured with those in theory but there were variations such as camo green on JNAF planes, and some units, mostly JAAF, painted them other colours such as red, yellow etc. Illustrations and photos show a single thicker line on the Judy so that is what I have gone for.

 

As for the cowilings of most JNAF aircraft with a single or sometimes twin radial engines, they seem to have been almost universally a shade of black in the early part of the war, but following the introduction of the green camo it varied between manufacturers. Nakajima still continued to use the black, and also used it on the Yokosuka P1Y1 Ginga they built. Mitsubishi Zeros, and presumably those built by Nakajima seem to have had black cowlings, but the Raiden did not, neither did the Kawanishi Kyofu float plane or the land based version of it - the Shiden. The D4Y3 built by Aichi likewise had green cowlings.

 

Hope that is of some use to the odd one or two of you.

 

Pete

 

 

Edited April 21, 2022 by PeterB

[trickyrich]

I know what you mean about the crazy prices on evilBay, plus the ridicules prices they charge for postage as well!

[PeterB]

50 minutes ago, trickyrich said:

I know what you mean about the crazy prices on evilBay, plus the ridicules prices they charge for postage as well!

Does it really cost up to £30 to mail a parcel from either the States or Oz? I could do it for a lot less from over here and we complain about our Royal Mail - maybe it's "super-doopa fast" fully insured? Having said that I know US and Oz Post are somewhat more expensive and probably less reliable to boot or so I have been told by residents of both those countries!

 

Pete 

Edited April 21, 2022 by PeterB

[Andwil]

1 hour ago, PeterB said:

Does it really cost up to £30 to mail a parcel from either the States or Oz? I could do it for a lot less from over here and we complain about our Royal Mail - maybe it's "super-doopa fast" fully insured? Having said that I know US and Oz Post are somewhat more expensive and probably less reliable to boot or so I have been told by residents of both those countries!

 

Pete 

I’ve never had any trouble with Australia Post, generally their service is pretty good, can be a bit slow at times, especially if anything has to come from/pass through Sydney.

 

AW

[PeterB]

1 minute ago, Andwil said:

I’ve never had any trouble with Australia Post, generally their service is pretty good, can be a bit slow at times, especially if anything has to come from/pass through Sydney.

 

AW

We used to have that problem with London, particularly Hackney sorting office which my supplier H.J. Walker (Hackney) Ltd used. It was never publicised but apparently they were rather prone to throwing strikes back in the 1980's for whatever reason!

 

Pete

[PeterB]

Usual problem of Macro lens, high gloss finish and artificial light so a pretty crappy pic, but as you can see I have got the undercarriage doors on and made a start on the decs.

Should look better with a coat of flat varnish sprayed on. Whilst browsing the pics in the Bunrin Do volume on the Suisei I noticed that it had the red/yellow/blue horizontal stripes on the wheel door so I knocked some decs up. I first came across these markings years ago when building a batch of Hasegawa Zero's but it was not until much later I found out what they are for, namely a sort of "traffic light" system for weighing the plane as you would not want to be overweight when trying to take off from a short carrier deck with no catapult assistance - it would probably be fatal!

 

Put simply the main u/c leg is in two parts, the upper fixed to the airframe through some sort of hinge mechanism, and the lower which has the wheel attached and is free to move up and down to a certain extent against the restraint of a damper. In this kit the doors come as one piece-

The instructions tell you to cut off part 4 which becomes the inner door mounted at the fuselage end of the wheel well, and the little tab I have marked "1" should be bent out and fits in the extreme outboard part of the well, apparently hinged to part 2. Although they do not instruct you to cut part 3 from part 2 there is a line (dotted in the pic) and I am pretty sure that as with the Zero this was a seperate part attached to the wheel mount whilst part 2 was fixed to the upper leg - on the Zero part 3 would slide up the inside of part 2 as the leg contracted when under load, such as whilst landing or when fuel and armament was being added. I presume there must have been some sort of pointer or index mark on the lower door, so as the plane settled under the added weight the pointer would effectively move up the coloured "scale" - blue was safe, yellow getting a bit close and red overweight - simple but presumably effective!

 

The drop tanks are ready to go on which just leaves the sighting tube in the windscreen, radio aerial and pitot tube to add after I have put the Hinomaru on - should be done on Saturday.

 

Pete

[PeterB]

Right, once they have had a coat of flattish varnish both my Suiseis will be finished.

Fujimi provide both a pair of drop tanks and also a couple of small bombs and the instructions imply you should fit both but I have my doubts about that. Francillon says the usual armament was a 500 kg bomb on the swing in the bomb bay and a couple of 30kg bombs could be carried under the wings giving a max load of 1234lb but it is not clear if that includes the weight of the tanks, so I have left the small bombs off. I did wonder if the tanks were only used on recce missions but I have seen pics of several with tanks that, unlike the dedicated - C recce variants, still had the dive sight fitted - pity I can't read Japanese!

Quite a nice looking aircraft, decidedly smaller and sleeker than the D3A Val it was meant to replace and nearly 70 mph faster than the D3A2 version. It could probably just about out-run a Wildcat but stood little chance against a Hellcat or Corsair!

 

Pete

Edited April 23, 2022 by PeterB

[trickyrich]

she's an interesting looking aircraft that for sure, nice work!

[PeterB]

My D4Y2 is finished and here it is along with the D4Y3 and B6N1 I have been building in the background.

Competent enough aircraft but they arrived too late due to a combination of the loss of 4 main carriers at Midway and the subsequent struggle against better USN planes in larger numbers. The tide of war had turned against them and they are perhaps not too well known outside of Japan.

 

Pete

[JOCKNEY]

Brilliant stuff Pete

Congratulations mate 

Cheers Pat 

[Grandboof]

Great result . They all are 

Martin H

[helios16v]

Nice collection.