Large RC concorde

[saaby93]

How large can a model be, before it can accomodate a human
https://www.youtube.com/watch?v=3zGeVSAHeuk

[Simpo Two]

That's impressive.

Size is one thing but payload is another - could that lift a human?

[Silver Smudger]

I like the to-do list down the window line!

[Petrus1983]

Wow. I imagine it requires quite a lot of skill to fly too.

[Wozy68]

Wow

[saaby93]

How long until these things begin flying at Mach 2?

[s2kjock]

Stunning.

I started off watching it and thought, yeah but the nose doesn't droop like the real thing and then ............

Assuming these sorts of large scale RC "models" are designed and built purely from scratch, how do they make sure it will actually fly? Lots of expensive trial and error work? Can they now use computer modelling in some way? Is the power to weight so much higher than real life aircraft that they just need to get a few fundamentals right and be very skilled at flying them?

[Simpo Two]

s2kjock said:

Stunning.

I started off watching it and thought, yeah but the nose doesn't droop like the real thing and then ............

But he raised it before the take-off run... maybe it doesn't like taking off 'drooped'.

[Dr Jekyll]

saaby93 said:

How large can a model be, before it can accomodate a human

https://www.youtube.com/watch?v=_yaKCkXa-rs

[FourWheelDrift]

saaby93 said:

How large can a model be, before it can accomodate a human

1/3rd scale is this is to go by https://www.youtube.com/watch?v=Uuq8rad3H-M

[Equus]

s2kjock said:

Assuming these sorts of large scale RC "models" are designed and built purely from scratch, how do they make sure it will actually fly? Lots of expensive trial and error work? Can they now use computer modelling in some way? Is the power to weight so much higher than real life aircraft that they just need to get a few fundamentals right and be very skilled at flying them?

The fact that wind tunnel models are used to predict the flying characteristics of real aircraft logically means that the reverse is true:if you replicate a real aircraft accurately, with the CoG in the right place and a few sums based on the Reynolds number, you can predict from the real thing how it will fly.

If you're designing a model aircraft absolutely from scratch, you can calculate the lift of the wing from published data on the aerofoil you intend to use, which then allows you to calculate the CoG location with reasonable accuracy (subject to fine trimming the finished model).

[Simpo Two]

Equus said:

The fact that wind tunnel models are used to predict the flying characteristics of real aircraft logically means that the reverse is true:if you replicate a real aircraft accurately, with the CoG in the right place and a few sums based on the Reynolds number, you can predict from the real thing how it will fly.

If you're designing a model aircraft absolutely from scratch, you can calculate the lift of the wing from published data on the aerofoil you intend to use, which then allows you to calculate the CoG location with reasonable accuracy (subject to fine trimming the finished model).

IIRC from my KeilKraft days, scaling down perfectly doesn't work beyond a certain point because aerodynamics are different. IE the model is scale but the air isn't. Probably in the same way that a model of a ship when underway doesn't have the same wash as the real thing.

I calculate CoG by putting a finger under each end and sliding them together

[Equus]

Simpo Two said:

IIRC from my KeilKraft days, scaling down perfectly doesn't work beyond a certain point because aerodynamics are different. IE the model is scale but the air isn't. Probably in the same way that a model of a ship when underway doesn't have the same wash as the real thing.

That's where the Reynolds Number comes in. The equivalent for displacement ships/boats is the Froude Number.

But yes, both only work so far: which is why bumblebees can fly, when famously early aerodynamicists reckoned they shouldn't be able to.

Edited by Equus on Sunday 14th November 20:21

[Simpo Two]

Equus said:

That's where the Reynolds Number comes in. The equivalent for displacement ships/boats is the Froude Number

Thanks - I didn't have the maths to work stuff out in actual numbers, just an instinct for it!

[J4CKO]

Simpo Two said:

That's impressive.

Size is one thing but payload is another - could that lift a human?

Cant imagine even the full size Joan Collins weighs much, its the number of miniature spirit bottles required that might be heavy.

[easyhome]

I might be completely wrong but I’m sure for the money some people put into these huge models you could get a ppl and hire a real plane, surely a microlight at least?

Each to their own and all that, but it does seem odd to me that people are that into flying, but don’t actually fly.

[Silver Smudger]

Maybe they are more into building, and the flying is just proof that they can build?

[stinkyspanner]

I wonder what the situation would be if one of those big rc planes crashed and seriously hurt someone? Not being a naysayer or anything, I find these things pretty amazing but are there any rules about where it could be flown?

[CarCrazyDad]

saaby93 said:

How large can a model be, before it can accomodate a human
https://www.youtube.com/watch?v=3zGeVSAHeuk

That's fantastic

[Simpo Two]

easyhome said:

I might be completely wrong but I’m sure for the money some people put into these huge models you could get a ppl and hire a real plane, surely a microlight at least?

Each to their own and all that, but it does seem odd to me that people are that into flying, but don’t actually fly.

Different interests. It's top-end model-making rather than bottom-end flying.