Short S.42 1912 monoplane

[Pete Fardell]

Big thanks to George for getting this forum up and running here. Great effort!

This is my latest indoor scale project, started when I came back from the IIFI feeling inspired to start on a new Indoor Nats model. It'll be 25" inch span,1/16 scale for rubber.
It's a Short S.42 which was very much based on the Bleriot XI, the main difference being it had a beefier undercarriage that dispensed with the Bleriot sprung 'bedstead' system. It was flown in the early days of the RNAS by the legendary Charles Rumney Sansam.
Some pics and two 3-views can be found here: https://flyingmachines.ru/Site2/Crafts/Craft28639.htm

Mine is based on the drawing from the Putnam book:'Short Aircraft since 1909'by C. Barnes.
(The other drawing on that webpage is from the Peter Lewis Putnam book:'British Aircraft 1809-1914' but to my eyes it's not quite as accurate as the other one.)
I only have the makings of a fuselage so far, with quite a lot of rigging done in the open section. I'll be using the same aerofoil as on my Bleriot, as plotted for me by Toon Verbruggen.

[Squirrelnet]

Great subject Pete I shall look forward to following this one.

Hopefully this will some of the wonderful flying characteristics of your Bleriot, the fuselage is looking pretty good already . Interesting that the Short appears to be a larger aircraft than the Bleriot given the different scales between your two models. I had always assumed it was more of a copy but clearly not

[Pete Fardell]

Sorry, should've said 1/14 scale, not 1/16. Span of original aircraft was 29' 3".

[Pete Fardell]

I now have wings! I used the same Toon Verbruggan aerofoil as on my Bleriot, which is quite drastically undecambered and a bit of a faff to make as none of the spars can be laid flat on the board. Done now though, so hopefully the effort will be worth it. Tips were laminated round a form.

The tailplane on this aircraft was also undercambered. I'm not sure how closely to replicate this on my model. I suspect such lifting tailplanes are a bit of a pain when it comes to trimming so am tempted to tone it down a bit, or maybe even flatten it completely. Does anyone have thoughts or experience with this?

[TheLurker]

The tailplane on this aircraft was also undercambered. I'm not sure how closely to replicate this on my model. I suspect such lifting tailplanes are a bit of a pain when it comes to trimming...

I built the Mooney peanut one with a reflex tail as per the plan, but didn't get enough intact landings out of it before I gave up repairing it to be able to tell whether or not I should have gone for a flat tail. However the flights it did make were quite... swoopy which suggests to me there was an up elevator effect giving a climb / soft stall cycle. 

I may be able to tell you more when I finally finish my "big" Chiribiri, see pic.

[cvasec]

Why not use the same section as you did on the Bleriot. You know it worked!
Ron

[Prosper]

Hi Pete,

Very nice, clean, accurate woodwork! I always enjoy your builds.

Stephen.

[Pete Fardell]

Why not use the same section as you did on the Bleriot. You know it worked!
Ron

My thoughts too. The real Channel Bleriot had a more or less flat tailplane though, so although mine is of thinner section I didn't have to worry so much about it looking unscale. I think it'd be more obvious on this one.
 I think I might do it flat and put 'cheat ribs' at each end to sort of suggest a bit of undercamber.

[Spiros]

The tailplane on this aircraft was also undercambered. I'm not sure how closely to replicate this on my model. I suspect such lifting tailplanes are a bit of a pain when it comes to trimming...

I built the Mooney peanut one with a reflex tail as per the plan, but didn't get enough intact landings out of it before I gave up repairing it to be able to tell whether or not I should have gone for a flat tail. However the flights it did make were quite... swoopy which suggests to me there was an up elevator effect giving a climb / soft stall cycle. 

I may be able to tell you more when I finally finish my "big" Chiribiri, see pic.

It's a masterpiece! Very clean job!! Bravo!

[Squirrelnet]

Why not use the same section as you did on the Bleriot. You know it worked!
Ron

Sounds like a good plan. My co2 Bleriot had a lifting tail but it has a modest undercamber rather than the deep undercamber you can see in the photo's. I think you are right to compromise on the section and you know the Bleriot one works

[Pete Fardell]

Thanks for the thoughts on the lifting tail. I really both Lurk's Chiribiri one and the Brainwood Bleriot's. However, I've now built mine with a flat underside and just a bit of camber on the top. Hopefully it won't misbehave.
I've also made the tailskid and rudder. I'm slightly worried the rudder is a bit small, but it is to scale dimensions. It would be a very quick job to make a larger one though, so I'll leave it for now.

[Pete Fardell]

I've made the wheels now too using a patent  "lolly stick" method which worked out rather well. The stick was removed after the first round of spokes were threaded on, then I cut more grooves in the rim and added another lot of spikes to fill in the gaps. Just two lengths of thread were used for each wheel.

[Pete Fardell]

Tyres are just rings of 1/32 balsa stuck together and glued onto the rims.
They still need painting of course, but here they are in situ and also a mock-up shot of all the bits now made. Dummy engine next.

[TheLurker]

I didn't know Sir Michael Caine built model aeroplanes.  Live and learn, live and learn.

[Squirrelnet]

Oooh that's looking very evocative already. Wheels look great too