New 1928 Junkers A50 Junior

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Stolch

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Stolch

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Yeah I think it’s Art Deco awesome. But those digital displays just ain’t right. I understand the need for an EFB or similar portable SA device but the panel should be populated with classic analog instruments.
And what up with the corrugated wings? Is it just a tradition thing or is there a benefit gained, like hundreds of low strakes?
Zenith bought the build rights to a somewhat similar aircraft a few years back and introduced it to the kit builder world with great fanfare, but never took it to market.
 

Tom DM

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EBGB Grimbergen airfield (N of Brussels, Belgium)
That's the way alli airplane wheels were back in the day, the better to roll over the ruts in the cow pasture.
Well, there is for sure enough prop clearance if one goes down.

History has a knack of repeating itself. Next time some bling-22 incher stops next to me, I'll ask if his granny was a Junkers.

But your observation (cow pasture) might hold truth... still today: those SUVs with low profile tires. Who should have guessed?
 
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Bill-Higdon

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The little son of Aunt Ju!

I like it but then I am biassed when it comes to corrugated structures. The EFIS-screens however clash a bit with the general appeal.
And it needs a canopy... for the pilot at least, that the passager freezes his head off: he choose to be the passager

Why are those wheels so massif?
Or Badger holes
 

flitzerpilot

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Hirwaun, Aberdare, S.Wales, UK.
Why do Flitzers have such tall wheels? The rolling radius irons out rabbit holes, they are relatively easy to build, provide good prop clearance especially with the big propellers swung by Rotec or Verner radials and present the aircraft on the ground at the ideal angle for flaring; but mostly they are 'period'. Tundra tyres by contrast are ugly and draggy and look horribly out of place on most aircraft although I acknowledge their usage for niche operations in the Bush. The Junkers Jr. reproduction fulfills the desire for ownership of such historical types but I agree that conventional instruments would be more suitable.
 

AdrianS

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Australia
Yeah I think it’s Art Deco awesome. But those digital displays just ain’t right. I understand the need for an EFB or similar portable SA device but the panel should be populated with classic analog instruments.
And what up with the corrugated wings? Is it just a tradition thing or is there a benefit gained, like hundreds of low strakes?
Zenith bought the build rights to a somewhat similar aircraft a few years back and introduced it to the kit builder world with great fanfare, but never took it to market.
I think the corrugated structure stiffens the skin a lot, albeit with a weight penalty for the skin.
It may still pay off with less supporting structure.
 

Tom DM

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EBGB Grimbergen airfield (N of Brussels, Belgium)
I think the corrugated structure stiffens the skin a lot, albeit with a weight penalty for the skin.
It may still pay off with less supporting structure.
No: it stiffens the skin in 1 direction without weight penalty as a thinner skin can be used and can introduce other significant weight-savings in parts around it.

Leaving apart higher fabrication costs, the only real penalty (which is very small below 100 kts) in aircraft is the extra drag linked to higher surface area. Close to all (alu) aircraft employ the method but most do it more discrete than the Junckers.

If a boffin (word used as a compliment) refers to a material as anisotropic he means that its characteristics change upon the applied direction. There are lots of such materials (wood for example). Sometimes this property is not wanted and solved by overlapping them in different directions (think laminated wood, woven fabrics, etc)
 
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Dana

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Why do Flitzers have such tall wheels? The rolling radius irons out rabbit holes, they are relatively easy to build, provide good prop clearance especially with the big propellers swung by Rotec or Verner radials and present the aircraft on the ground at the ideal angle for flaring; but mostly they are 'period'. Tundra tyres by contrast are ugly and draggy and look horribly out of place on most aircraft although I acknowledge their usage for niche operations in the Bush.
What does the Flitzer use, motorcycle wheels?

The subject comes up occasionally with regard to "latter day antiques" line the Hatz. Original wheels (and tires) are pretty rare, but motorcycle wheels aren't made for the kind of side loads a plane sees. I've heard of people using automobile compact spares with a suitable hub.
 

PMD

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Apr 11, 2015
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Martensville SK
Motorcycle wheels are extremely easy to make to tolerate some more side loading. You start with OTC rim and make a new hub that is much wider than the motorcycle needed. Then you simply lace it with sufficiently strong spokes. Back yard tech. BTW: if the spoke angle exceeds where the holes in the dimples of the rim are, you just need to buy the rim further upstream in the supply chain as undrilled and make up a jig to drill at new angle(s). IIRC, the dimples are spherical so the spoke "nuts" will align. Note on the Werner powered one there s a BEATIFUL set of wheel disc fairings!!!! TASTY TREAT!
 
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Stolch

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Jan 10, 2022
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What are those, those, ummm I dunno, red-striped thingies mounted to the landing gear that are visible just above the wheels in Tiger Tim’s photo?
 

Dan Thomas

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Sep 17, 2008
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Corrugated wing skins bother me. Spanwise flow is a well-documented phenomenon, and corrugations are just going to add drag and turbulence. Even poorly-shrunk fabric on a wing will allow it to balloon upward and interfere with the flow, slowing the airplane.

1657855083876.png
 

Tiger Tim

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Thunder Bay
Corrugated skins are sub-optimal from a performance standpoint but pretty ideal from a ‘replicate a nearly hundred year old design’ standpoint. That and they’re a heck of a conversation point.

If my airplane life didn’t already have focus and direction I’d be looking more into this modern Junkers.
 

scramjetter

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Mar 2, 2020
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That's a beautiful celebration of such an old design! I did some searching and found that the same company is doing a side-by-side version with retractable tricycle gear, the A60. (article in German)
 
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