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Not 744 but pretty amazing...

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Member
Registered: May 2009
Posts: 503
Location: Mumbai, India
https://www.youtube.com/watch?feature=player_embedded&v=-Rt9zX1rZFU
Member
Registered: Dec 2009
Posts: 334
Location: KTPA
Farrokh:

As a long time R/C Heli pilot, I can appreciate the commitment such a project takes. Pretty amazing, thanks for sharing.

Best- C
Moderator
Registered: May 2009
Posts: 5140
Farrokh, you can post all aviation related topics in "Hangar 7" :-)
Member
Registered: May 2009
Posts: 944
Most remarkable!

How much would such an aircraft cost, approximately?
_______________
Best wishes,

Phil Bunch
Member
Registered: Jun 2011
Posts: 307
Location: TX
10k for each engine they are miniature turbines hate to think the time effort and energy that has gone into the fuselage...a rich mans hobby.. I now consider myself normal did you see the F14 go up in a ball of flame :-(
Member
Registered: May 2009
Posts: 958
Location: Chicago
Pretty amazing. Is the landing done 100% visually by the pilot? Or are there flight instruments to look at? I can imagine that lining up on final would be fairly challenging, not to mention making onto the runway ay the right speed to flare and land safely.
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Will /Chicago /USA
Member
Registered: May 2009
Posts: 503
Location: Mumbai, India
Sorry Hardy! I assumed the Pit was for all non PSX stuff...

Quote
The place for forum problems and other urgent off-topics.


I must learn to read.... apologies...

will do..

FC
« Last edit by farrokh747 on Tue, 14 Jul 2015 02:57:38 +0000. »
Member
Registered: May 2009
Posts: 503
Location: Mumbai, India
The builder is Peter Michel, and here's the concorde he built...

https://www.youtube.com/watch?feature=player_embedded&v=2ZeGylHqo7M

fc
Member
Registered: Dec 2009
Posts: 334
Location: KTPA
All visual- and the new R/C pilot's greatest challenge- finding the extended centerline while "flying" from a fixed position (typically around center field). Still- lots and lots of practice (years/decades) before tackling a project such as this with 4 turbines.

The cost in money & TIME is immense. Still, like everything, it's ALL relative. I would pull up to F3C meets with 2 airframes in my Volvo whilst others would arrive in Prevost motor coaches with a dozen airframes and support staff. We would both enjoy the event....

Best- C

Will wrote
Pretty amazing. Is the landing done 100% visually by the pilot? Or are there flight instruments to look at? I can imagine that lining up on final would be fairly challenging, not to mention making onto the runway ay the right speed to flare and land safely.
Member
Registered: May 2009
Posts: 944
How do the 4 miniature turbine engines keep their power matched? Is there some sort of computer control?
_______________
Best wishes,

Phil Bunch
Member
Registered: May 2009
Posts: 958
Location: Chicago
The planes (both Concorde and the A380) seem to be over-engineered. Meaning higher thrust-to-weight ratios than the real things. They just spring up into the air pretty quickly, as if they have thrust and runway to spare. Any comments about that? Do they worry about having enough runway? Are sophisticated performance calculations needed, or do they have adequate performance reserves for even the shortest hobby runways?

Without flight instruments and without being able to feel a buffet, how do they know when they're getting too slow? How do you judge your approach speed? Probably by power setting, I assume, but how do you know what power setting to use? (Trial and costly error?)
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Will /Chicago /USA
Moderator
Registered: May 2009
Posts: 5140
They have a lot less inertia.

They have no flaps.

You probably land them at VREF+100 :-) ... in the respective ratio of real size to model size.


|-|
Member
Registered: May 2009
Posts: 958
Location: Chicago
The relative lack of inertia is pretty apparent. If they rotated and maneuvered proportionately to the way the real things do, the passengers would have whiplash from being flung about.

Yes, I agree with VREf + 100. I would bet they are rarely at their performance margins.

In the RC community, would it be a sign of accomplishment and skill as a pilot to have the flight path on takeoff and landing mimic the real aircraft? Or are they more concerned with just getting their amazing models successfully into the sky?
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Will /Chicago /USA
Moderator
Registered: May 2009
Posts: 5140
Will wrote
If they rotated and maneuvered proportionately to the way the real things do, the passengers would have whiplash from being flung about.

These little pax too, and their stomachs, have very little inertia :-)

When you jump off a tower, how high must the tower be so that the touchdown will kill you ...

... if you're a mouse

... if you're a human

... if you're an elephant

... ?


I have seen a human surviving a fall from 12 meters onto grass without major injuries. I guess this wouldn't work for an elephant ...


|_|ardy
Member
Registered: May 2009
Posts: 958
Location: Chicago
Yes, of course, but I'm talking about perceived velocity, as in: if this were a real movie of a full-sized plane, the passengers would all be bruised and writing angry letters to the VP of passenger comfort.

But mouse passengers, in a model aircraft? Just another day. Like sitting on a tree branch in a stiff wind. (Do mice do that?)
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Will /Chicago /USA
Moderator
Registered: May 2009
Posts: 5140
Just in theory :-) I am against animal testing ...
Member
Registered: Jan 2013
Posts: 318
Location: YSSY
RC turbines have between 9-25kg of thrust, so if the 4 engine model weighs 80kg, the thrust to mass ratio is between ~1:2 to 1.2:1 (the latter having more thrust than weight, you can hang the thing from its engines vertical and still climb).

Big scale (real) jets have thrust to mass ratios on order ~1:3.

The mouse stomachs are just going to have to get used to it... the force will be minor, given F = m*a, and m is very small for a mouse stomach... :)
Member
Registered: Dec 2009
Posts: 334
Location: KTPA
Balt is completely correct- One of the most difficult things for an R/c scale pilot to learn, is to operate in a SCALE fashion. The size translates far easier than operation- which is why, when you see a scale model that is capable of operating in a scale fashion (aerodynamically and pilotage wise) it is a RARE thing of beauty.

Usually, the "scale" is limited to the visual model- operating far too fast and erratically.

Best- C
Member
Registered: May 2009
Posts: 479
Location: EFTO
Will wrote
Like sitting on a tree branch in a stiff wind. (Do mice do that?)
No. Squirrels do, though! And they have built-in parachutes!

Cheers,
Martin
PSX Zoologist
Member
Registered: Jul 2014
Posts: 170
Location: Antwerp
Some people have golden hands, maybe even from an other planet!
In one word amazing
http://youtu.be/is5erfr4mGg
Ivo
Member
Registered: Sep 2009
Posts: 176
Location: South Bavaria
Ivo de Colfmaker wrote
Some people have golden hands, maybe even from an other planet!
In one word amazing
http://youtu.be/is5erfr4mGg
Ivo


Yes, really amazing. Especially the solution with the slats seems to be more elegant then on the original. A few years ago I saw a film on the german TV ( of course the builder is from Germany :mrgreen: ) The documentation showed him building, I think it was an A380 or A340, and all the problems he had to solve.The end of the film showed the first flight of the model. This was not done by him, but by an professional RC pilot. He was too nervous to fly his masterpiece.
Cheers
Member
Registered: May 2009
Posts: 944
Ivo de Colfmaker wrote
Some people have golden hands, maybe even from an other planet!
In one word amazing
http://youtu.be/is5erfr4mGg
Ivo


Another amazing RC aircraft, with fully functioning leading edge slats and flaps.

How does one learn to fly such a thing, with your first flight being a solo? In some ways, it seemed to fly like an ordinary small single-engine prop RC aircraft.

Landing seemed to be done via descending in short bursts, instantly pulling the aircraft up if your descent rate seemed too fast. As a passenger, I would prefer a smooth, glideslope-based flight path!
_______________
Best wishes,

Phil Bunch
Member
Registered: May 2009
Posts: 503
Location: Mumbai, India
I had posted this earlier (i think)

she dosen't fly, but equally (if not more) amazing LOD

https://www.flickr.com/photos/lucaiaconistewart/sets/72157632208677161

https://www.youtube.com/watch?v=_v3JQCcG61I

flap drive system

https://www.youtube.com/watch?v=1LckG_P135Q

reversers

fc
Member
Registered: May 2009
Posts: 958
Location: Chicago
farrokh747, that man is the Hardy Heinlin of paper and glue.
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Will /Chicago /USA

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