What is the logic behind 2/3rds Red Baron build?

[cronus]

If you are gonna go that far why not the whole hog? It is almost there, man. You scared to fly in it?

[Hermit]

Might be a matter of economics. The market for full-scale Fokker triplane replicas is already saturated. A kit costs ten grand and you still have to supply your own engine. Maybe the two thirds model is aimed at people who don't want to spend quite so much on a toy.

[cronus]

The engine does look small in the replica I suppose. Could carry a cat or dog though?

[mistermack]

Fuck this Alzheimers.
I read an article on someone doing something very similar with another plane. And he made a very clear and convincing case for not going full-size. Buggered if I can remember what it was though.

They do look the same in the air. Actually, I think that the one I'm thinking of could carry a pilot. Spitfire or something.
The spitfire was a lot bigger than that Fokker, so 2/3 is still quite big enough to carry a man.

I didn't realise how tiny those WW1 planes were.

[Clinton Huxley]

Maybe he's 2/3 human size?

[cronus]

Maybe he's 2/3 human size?

A lot are with some surgery.

[Animavore]

Maybe a full-sized one won't fit in his gargae.

[klr]

The real thing was small enough as it was. Anyway, if this reduced size replica is an a perfect scale reduction in all aspects, it would have substantially different flight characteristics than the original.

[cronus]

Still doesn't make sense to me.

[Xamonas Chegwé]

It's a matter of Maffs and economics. A 2/3 replica has weight & volume only 8/27 of the original. So, while 2/3 might look like only a small saving, it uses less than a third of the materials and takes a far smaller motor (and much less fuel) to fly the thing.

[cronus]

The trouble with efficiency explanations is there is no sign humans are except for the bean-counters who get torched every-time they get it wrong.

[Clinton Huxley]

XC, coming over here with his "maths" and "explanations", the damned bully.

[klr]

It's a matter of Maffs and economics. A 2/3 replica has weight & volume only 8/27 of the original. So, while 2/3 might look like only a small saving, it uses less than a third of the materials and takes a far smaller motor (and much less fuel) to fly the thing.

Compare the original specs:

http://en.wikipedia.org/wiki/Fokker_Dr. ... .28Dr.I.29

... against those of the replica:

http://www.billhempel.com/triplane/index.php

So it's around 2/3 by dimensions. It's a lot less than 8/27 of weight. Maybe half that again, or less. Between that all the extra wing area area (about 50% more in relative terms), it must have an extremely low wing loading - i.e., a very little weight being lifted by a lot of wing. That's just in comparison to the original Dr.I, which had a very low wing loading by any measure.

But then, the replica is only an RC model.

[Xamonas Chegwé]

It's a matter of Maffs and economics. A 2/3 replica has weight & volume only 8/27 of the original. So, while 2/3 might look like only a small saving, it uses less than a third of the materials and takes a far smaller motor (and much less fuel) to fly the thing.

Compare the original specs:

http://en.wikipedia.org/wiki/Fokker_Dr. ... .28Dr.I.29

... against those of the replica:

http://www.billhempel.com/triplane/index.php

So it's around 2/3 by dimensions. It's a lot less than 8/27 of weight. Maybe half that again, or less. Between that all the extra wing area area (about 50% more in relative terms), it must have an extremely low wing loading - i.e., a very little weight being lifted by a lot of wing. That's just in comparison to the original Dr.I, which had a very low wing loading by any measure.

But then, the replica is only an RC model.

My figures were based on using identical materials to the original - obviously, lighter, yet stronger materials are available these days - hence the disparity.

[klr]

...
My figures were based on using identical materials to the original - obviously, lighter, yet stronger materials are available these days - hence the disparity.

Let's hope it's better built than the original:

http://en.wikipedia.org/wiki/Fokker_Dr.I#Wing_failures

...
Postwar research revealed that poor workmanship was not the only cause of the triplane's structural failures. In 1929, National Advisory Committee for Aeronautics (NACA) investigations found that the upper wing carried a higher lift coefficient than the lower wing — at high speeds it could be 2.55 times as much.
...

In other words, the upper wing was always trying to detach itself from the rest of the airframe, especially at high speed.

Anyway, I wonder if Bill Hempel is considering a 2/3 replica of the Zeppelin-Staaken?

http://en.wikipedia.org/wiki/Zeppelin-Staaken_R.VI