Replica plane scaling visualisations (BF109 edition)

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Tiger Tim

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I feel 5/8 scale is a little cramped. 75% scale would work for a Hurricane
I wholeheartedly agree. Having crammed myself into WPN twice now, there’s no way I could actually fly it.

Shame my group never did pull off a full scale Hurricane…
 

cluttonfred

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I'll oragise that shortly. I'll have to alter the camouflage scheme of course to represent Middle East Theatre! Of course, scaling it up a bit would help as I feel 5/8 scale is a little cramped. 75% scale would work for a Hurricane

LOL, the problem with that approach is that I already have Sindlinger Hurricane plans and you already have too many projects. 😜

I’d be more than happy just to hear what small tweaks you would make to the existing 5/8-scale Hurricane design for a more realistic look without any major changes.
 
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I knocked these visualisations up quickly yesterday so I could get some idea of how each modeling scale looks. Posting here in case these are useful for anyone.
I find being able to picture the sizes helps to know what the end result will look like.
Why is it that the bigger the scale, the smaller the bulge in the man's crotch, but no change to the woman's bust line?
 

Tiger Tim

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WHAT? Now you have to tell us about the full scale Hurricane........!
"Please".
In short there was at one time everything but a fuselage either present or located and available to restore a Mk.XII. The main driver behind it all passed a year and a half ago but the rumour is there’s an engineered set of drawings somewhere in the hangar for a welded tube fuselage that’s a direct replacement for the hollow-riveted nightmare that Hawker designed.
 

flitzerpilot

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Thanks Shayde, It's still a little 'chubby' and could do with a little bit of a stretch. I'll make some further simple improvements and create a stretched version to see how that looks. I'll also do the tropicalised version for Matt.
 

Shayde

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I looked at building a scaled down Me-109 many years ago. After running a bunch of numbers I concluded the 80% scale was the minimum. It is possible to build a 80% model without distorting the shape. For example, I was able to lay a tape measure on the Me-109G-10 that Planes of Fame has at Valle, AZ. The cockpit rails measure 30" wide to the outside edge. 80% would be 24" which is as wide as my Thatcher CX4. I don't remember the fuselage depth at that point but it is deep enough to work. 80% gives a large enough wing to make stall manageable. The canopy might be the biggest problem since it isn't very tall. The best option for the canopy might be the Galland hood. The other problem might be the tall narrow landing gear. The landing gear was splayed out further on the late models so that would help.

I did some measuring of my own in a large area to get a feel for the sizes before I knocked up those renders, and the 80% felt about the right size, if 100% was out. Perhaps still a bit small, but at 80% it's almost bang on half the volume of the 100%, so it gives one a better idea of how it compares to it.

Out of curiosity, what caused you to not end up building your 109?
 

wiloows5050

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No that the original prototype that Fred and his built. It’s still owned by his son Lyle. It hanger up in Puyallup Washington
 

Shayde

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Mo' comparisons, mo' planes.

This time we have the BF109E, the BF109F, the FW190A, the Zero, the P40, and the Corsair. I've checked and scaled these models to their published sizes. Even so, that Corsair looks huge. These models will have varying degrees of accuracy in regards to details. Just look past those...

In hindsight, the dark-coloured platform wasn't a great choice.

So, let's start with the real plane sizes...

100%:

100.jpg

80%:

80.jpg

75%:

75.jpg

67%:

67.jpg

50%:

50.jpg

W.A.R. replicas did tend to deal with the larger fighters out there, Mustang, Corsair, Thunderbolt, Seafury, in fact the original W.A.R. plane, the FW190 is about the smallest of the lot, and you wear it more than sit in it.

I see your point. At 50% the other planes don't look as bad as the 109, the 109 being a small plane to start with.
 

ScaleBirdsScott

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These are really cool renders and a good way to visualize vs how I've been doing it. I lost patience for using rendering and art modelling a long time ago.

What we did with the ScaleBirds concept and what I tend to think makes the most sense for any replica project that isn't being done by scaling original drawings via slide rule, is just find the size of airplane you want first. Then just adjust the scale of the original arbitrarily over top of the idealized template until it overlaps as close as possible. Then tweak from there either up or down to something that's vaguely round or nominal or fractional, or accept that the ideal final resulting machine will have so many subtle deviations from the original that you can call it an 80% when really it's the 81.42% fuse and a 82.14% wing with a 76.4% landing gear and a cowling that's stretched 106% athwartships and 98% longitudinally from exact proportion at 81.42% and the cockpit is at 93% scale with some canopy elements pretty-much unchanged from original and yet the whole thing is forward about 20% from where it should be. Ultimately if you're within 5% of a notional scale factor on 90% of the shapes, and stick the details in the relationally correct spots, no-one is going to be able to really say you're wrong.

I can't find any good data on one at this point, but would HIGHLY doubt a WAR 109 was truly 50%. Must be closer to 65-70% but everyone just knows that the WAR were 'generally' 1/2 scale with a very broad brush of what 1/2 means.

Then the real challenge is just whether your original 'ideal airplane' actually ends up what you wanted afterall. It can start getting into a real headscratcher if you think too hard about it. Maybe new engines come out that would affect the best possible design, or the detailed design stage reveals issues with fit that weren't fully appreciated during the initial layout stage. Maybe you get 87.6% thru the build and wonder why it wasn't just that 3% bigger so that a 34.79% more powerful engine could fit and allow the scale to be 130% more accurate by moving the cockpit 11.1% further aft, or maybe a 1.3% percentage increase of the wing volume would have allowed using a newly available nicer looking 81.31% landing gear scale vs the 76.4% you settled on due to sizing of available wheel/tire combos.

Fun times!

And then yes, what's interesting about the array of different warbirds at different scale levels is that you just got to pick from the different batches different warbirds and using the comparison of the person standing next to the nose, you can end up with a smattering of scales that end up with different warbirds at nearly the same final size and proportions. So a "5/8 P-40" can equate to roughly the "3/4 109" and so on.
 

Tiger Tim

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What we did with the ScaleBirds concept and what I tend to think makes the most sense for any replica project that isn't being done by scaling original drawings via slide rule, is just find the size of airplane you want first. Then just adjust the scale of the original arbitrarily over top of the idealized template until it overlaps as close as possible.
Reminds me of some of the early scale plastic models. While today we have popular scales for model building, at one time they did what’s now referred to as ‘box scale.’. Just like it sounds, they made the kit however big would fill the box it was to be sold in.

I guess the smallest successful scale warbirds could be called ‘pilot scale.’
 

ScaleBirdsScott

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Pilot Scale yeah I can dig it, even if even that allows some fudge factors based on interperetation. But makes some intuitive sense? I'd say if we call it the smallest that a pilot can practically fit regardless of other things it's probably in the 50-70% window.

Then there's various "engine scales" you might find where the size/power of available engines more-or-less drives it. For radials I'm starting to notice a "Verner scale" where everything is sized to whatever works with the engines' diameters, typically in the 65-80% region for WWII stuff; but then it's 80-100% for WWI due to performance more than size.

And there's probably a "V8 Scale" which could be roughly plotted in the 75-85% realm.
 

Shayde

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What we did with the ScaleBirds concept and what I tend to think makes the most sense for any replica project that isn't being done by scaling original drawings via slide rule, is just find the size of airplane you want first. Then just adjust the scale of the original arbitrarily over top of the idealized template until it overlaps as close as possible. Then tweak from there either up or down to something that's vaguely round or nominal or fractional, or accept that the ideal final resulting machine will have so many subtle deviations from the original that you can call it an 80% when really it's the 81.42% fuse and a 82.14% wing with a 76.4% landing gear and a cowling that's stretched 106% athwartships and 98% longitudinally from exact proportion at 81.42% and the cockpit is at 93% scale with some canopy elements pretty-much unchanged from original and yet the whole thing is forward about 20% from where it should be. Ultimately if you're within 5% of a notional scale factor on 90% of the shapes, and stick the details in the relationally correct spots, no-one is going to be able to really say you're wrong.

One of the attractions of going 100% - no need to bother about what to scale where to make it work. There's also the question of whether you're trying to just recreate the looks, or you're aiming for similar flight handling too. The Jurca 75% scale 109, for instance, has a different wing profile from the Messerschmitt one, so it won't handle the same. Presumably you could only recreate the handling if you had the same size, shape and weight as the original, but I'm not any kind of expert in aerodynamics.

Of course, doing 100% brings its own challenges...

I can't find any good data on one at this point, but would HIGHLY doubt a WAR 109 was truly 50%. Must be closer to 65-70% but everyone just knows that the WAR were 'generally' 1/2 scale with a very broad brush of what 1/2 means.

They do not currently offer a 109 to the public, but I believe it's a work-in-progress by the new owner. I wonder what size he will go with.
 

cluttonfred

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Reminds me of some of the early scale plastic models. While today we have popular scales for model building, at one time they did what’s now referred to as ‘box scale.’. Just like it sounds, they made the kit however big would fill the box it was to be sold in.

I guess the smallest successful scale warbirds could be called ‘pilot scale.’
Peanut and Pistachio rubber-powered flying scale models are like that—maximum dimensions rather than a specific scale. It means planes with relatively low AR (Fike E, for example) can be quite competitive because they can fit so much wing area in.

6F6B9D1B-4146-47AE-8C50-5D9C5340DC7F.png B4778652-973B-4C77-B18F-2263E172C7BB.png

If we took the same approach with WWII warbird replicas, I suspect some Italian and Japanese fighters would be popular…and of course the Polikarpov I-16!
 
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RJW

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If I were to build a 109 replica it would be 100%. 109s are small airplanes. You really have to go see one to realize how small they are. They're not much bigger than an Archer or C172. I would use similar construction methods as the original but greatly lightened. Target empty weight would be around 1800lbs. Power would be a LS V8 of around 400hp (early 109s flew on 600hp and weighed around 4000lbs). I'd also change the airfoil to something more suited to recreational flying (no slats). I'd likely replicate a 109f just because I like it the best. So what I would end up with would be a larger, reasonably high performance sport plane that would look like a 109f.

Rob
 
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