Special Hobby N.A. BT-9

[Whirly]

Hello,

 

I started 2022 with a strong will to decrease the number of abandoned builds I have in my stash (who does not have them?) and selected this one:

 

 

Inside not what you would expect, since the box is simply a better way to avoid loosing everything with a damned end-opening box 😁

 

 

More details to follow...

Thanks for looking!

 

 

[Graham Boak]

You are lucky not to have a yellowed canopy, unlike mine.

[Whirly]

Hi Graham, it's a very hit and miss issue: I have other kits with badly yellowed canopies e.g. Special Hobby F2G Corsair and AML N.A. O-47. Probably much more but I don't dare check all of them otherwise I'd get depressed! 

 

I started the BT-9 back in 2007 (!) when my local club had a membership build of all Texan variations for the annual model show. It was a success but this model didn't progress beyond main airframe assembly.

Main reason was my inability to understand all the different pre-Texan flavors and make some order in the very fussy instructions provided.

Fourteen years later my ignorance of the subject was not less, but more infos are now available over the internet and I dove into a lot of reasearch to finally complete this model with a reasonable degree of accuracy.

This process was in part successful, since I managed to understand most of the "NA-16 derivatives" as they are called, but after observing several images I got even more confused regarding the BT-9 variants and their differences...

 

I finally identified a couple of subjects with multiple images, but there are no aftermarket decals that I know and the yellow codes are non standard, so in the end I decided to go for the box supplied scheme despite being supported by only one side image.

 

And now, without further ado, it's time to work on the model! 

 

Green cockpit is not correct, at the time I sheepishly followed SH instructions...

 

 

Better now after an auminium repaint! The internal structure was added with plastic rod, nothing is provided in the box.

Here you see also how I did some improvements to the engine mount: out of the box there is nothing more than the resin engine itself to be sanded back at your discretion, then you are on your own placing the cowling around.

I added a spacer about 1,5mm thick behind the engine, then glued nine plasticard disks to the cylinder heads and now the cowling is a tight fight in the correct position.

 

 

The u/c stubs were refined and a fairing was added to the nose underside using parts of old drop tanks. I don't know its purpose but it is very visible in images and completely forgotten by SH.

You see also the landing light recesses I added cutting the wing leading edge: these are omitted from the box and will need further work to devise the lamps and transparent covers.

 

 

This is the cowling with four resin micro fairings added as per instructions. This is another feature often changing in images and I'm not sure what is right for my specific example.

 

 

 

And here some finishing to do after a coat of Mr.Surfacer to blend the surfaces, the cowling is just a dry fit.

 

 

 Thanks for looking!

[Graham Boak]

The most easily available way into the NA.16 variants is Dan Hagedorn's work, either the Warbird Tech which is a good summary of all the variants, or the later thicker book for which I can't find a reference to the publisher at the moment.  I can well understand why confusion sets in when looking at internet sources.  

 

I must admit not having noticed these four fairings before.  The fairing under the nose is in the position for the engine air intake, so are you sure that doesn't have a opening at the front?

[Whirly]

Hi Graham,

 

I admit I'm no less bewildered regarding the undernose fairing but I can't see any opening:

 

 

 

 

You can see in the images above also some variations of the fairings on the engine cowling. Even more here:

 

 

I found a preview of the excellent book by Dan Hagedorn at this link, unfortunately it's just a teaser to taste how good it is but no pages from the pre-Texan era are visible.

 

https://books.google.it/books?id=vpcgBQAAQBAJ&printsec=frontcover&redir_esc=y#v=onepage&q&f=false

 

It currently commands very high prices so it's not an option for me, I will try to get hold of the Warbird Tech book as an alternative. Thank you for suggesting them.

[Graham Boak]

Nice photos.  I notice that they show the cowling bumps on aircraft with the fixed slats, which I think - I really should check first but the book is in the loft - makes them BT-9C.  I don't see why there should be any connection between the two, but it could just be an unconnected introduction on this variant.  The bump underneath clearly isn't for the air intake, as this (these?) are on top of the cowling.  The only vague suggestion I can make is that it is somehow associated with a fuel pump - the SNJ-2 apparently had a slightly wider centre-section to include such a device but this was further aft and on a fairly different airframe.

 

From a modelling point of view, note that 488 in the foreground appears to have retained the earlier darker blue on the canopy frame.  It also has the shorter opening "gunner" rear canopy rather than the original design of longer fixed section for pilot training only.  (Does that mean these are BT-9B?  I really must dig out those books again.

[Whirly]

Back to this build after a long hiatus: first I delved into various books to finally understand all the nuances of BT-9 versions but many grey areas remained, so in the end I threw the towel and went more or less the straight from the box route!

Then I suffered lack of modelling time so progress was very slow, but I trust I will finish it by the deadline.

 

Here you see the cockpit ready for joining the canopy and the wing landing lights built with acetate smash moulded on the leading edges.

 

The propeller is very basic and not so accurate: I replaced the shaft with a metal rod and the boss with a longer plastic rod, then a couple of plasticard disks were added to simulate the balancing weights.

 

 

Here it is all primed, in the final stages of improving the canopy fitting. Note also the resin slats which are quite difficult to fit without appearing like a last minute addition.

 

 

Nearly ready for paint! Note the carburettor intake above the nose: the instructions are very confusing, I chose piece B16 for the BT-9, which seemed the most similar to what I can see in images of the real plane.

 

 

 

Time to paint!

Canopy is masked with a Pmask product, most useful but could have been better since the vinyl material struggled to adhere to the uppermost curved windows...

 

 

Fast forward a few days (I realized later I didn't take images during the painting process 🙄) and here it is in its garish livery:

 

 

Thanks for looking!

[jean]

Beautiful!!!

This build is turning out really neat, and I won't deny that I love these colors!!!

 

Great show.

 

JR

[Whirly]

Thank you @jean !

Here another update, decalling is nearly completed 

 

 

 

 

 

 

 

 

[arfa1983]

Very nice! Very striking scheme that's going to take pride of place in the display cabinet 

 

The colour match between the wings and the numbers is perfect. I was going to ask if you masked them.... surely not?!

Edited March 3, 2022 by arfa1983

[Whirly]

If you get a little closer you see things get a bit worse 🙄

Numbers are from the decal sheet and they are noticeably off register to the underlying white layer. Now I touched up a bit he smaller ones with blue, because the white showed really too much, but there's little more one can do. It's also a non standard format which you can't find in aftermarket sheets.

Anyway, thanks for your good words: I also find it a fabulous scheme and can't look forward building more subjects I have in my stash!

 

 

 

[Graham Boak]

I can't find any reference calling for the field number to be on the leading edge, but several photos of these aircraft show them present.  It may have been specific to one training field.  I'd hoped that these could be tied to the serials but no.  That would at least have helped sort out the difference between variants.  If you care any more:

BT-9 - basic airframe, unarmed, long fixed canopy for pilot training

BT-9A - armed variant with short openable rear canopy for gunnery training

BT-9B - improved original, long canopy,  perhaps with outer wing washout, equipped for optional forward firing gun, and with the four bulges for cowling vents,  They also seem to have had the fairing aft of these vents absent on others, as shown in your photos.

BT-9C - fixed slats outboard and full armament option with short canopy

BT-9D - one aircraft only as testbed partway to BT-14 modifications.

only comparatively small numbers of each were built.

 

I can't find any explanation/reason for the bulge under the nose aft of the cowling, it does not appear to be visible on other sister variants.  Possibly this is because many photos don't show this area clearly.

[Whirly]

Hi Graham,

 

I surely care! I had to cut some corners with my model, otherwise I will never finish it. My interest in the historical side is however well alive and your research is very helpful.

Let me say however, that some details like the fixed slats are really difficult to tie to a specific variant: if you check photos available online a lot of cases don't match. Maybe they were retrofitted or there were other reasons.

Another thorny detail is the pitot for example: you can find it in at least three different locations and shape and I'm going to flip a coin to make a choice for my model!

 

 

[Whirly]

When I was nearly ready to cross the finish line, another issue came out. Please look at the stance on the u/c and wheels and compare with the real one below. Way too high!

Unfortunately it is not only a case of shortening the legs: actually the u/c is totally wrong because the bent section should emerge from inside the faired part, not below it.

 

 

 

Now totally discouraged with this model, I removed entirely the u/c and I'm going to fit the original big fairings: maybe they are not really accurate for a late service BT-9 but at this point I don't care anymore...

 

 

 

 

[Whirly]

I forgot the deadline on monday but I actually managed to finish this beast!

Just the wire aerial missing but I'll call it done.

In the end I'm very satisfied with the result and want to say thank you to all who contributed with precious informations or simply encouraged me along this tortuous path, not least to the moderators for setting up another KUTA edition.