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Do large RC airliners like the huge Emirates RC A380 still need all the same control surfaces that a real A380 has I,e leading edge slats? If not why is this the case.

Many thanks for your time in advance Lee

Camille Goudeseune
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Lee
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    Consider an edit-- a leading-edge slat is arguably not a control surface. – quiet flyer Jan 10 '23 at 12:33
  • Also the term you want is probably l.e. flaps not slats-- – quiet flyer Jan 10 '23 at 12:38
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    Related : https://aviation.stackexchange.com/questions/35723/why-do-model-aircraft-fly-and-maneuver-so-differently-from-real-aircraft – quiet flyer Jan 10 '23 at 12:49
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    @quietflyer Slats (and other high-lift devices) are sometimes grouped under secondary control surfaces (e.g. SKYbrary says "Secondary flight controls are intended to improve the aircraft performance characteristics or to relieve excessive control loading, and consist of high lift devices such as slats and flaps as well as flight spoilers and trim systems."). – Bianfable Jan 10 '23 at 12:51
  • @Bianfable -- good point – quiet flyer Jan 10 '23 at 12:52
  • High-lift devices (slats and flaps) are normally used also as control surfaces on fighters. On jetliners they are used mainly, if not exclusively, as... high-lift devices. Since we are dealing here with an A380 then I suppose it would be better not to call them control surfaces. – sophit Jan 10 '23 at 13:10
  • If you fill a scale-down model A380 with helium it could also fly without an engine. – user3528438 Jan 11 '23 at 13:13

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I've seen several r.c. airliners first-hand and none had leading-edge flaps. It's a matter of scaling. Kinetic energy scales according to velocity squared and these r.c. planes don't land at the same velocity as their full-scale counterparts, so stopping distance is less of an issue and the need to slow down the touch-down speed a bit more vanishes.

Same reason that the r.c. versions usually also dispense with wheel brakes, thrust reversing (some actually do have this, the electric ducted fans are simply run in the reverse direction), elaborate Fowler flaps (simpler hinged flaps serve instead), etc.

There are also Reynold's number effects to consider, but we really don't need to get into that to understand why features such as operating leading-edge flaps are usually omitted from r.c. model airliners.

In any oddball cases where the pursuit for scale accuracy is carried so far as to include features such as leading-edge flaps, it is clearly not a matter of a need for such features!

Here's a related ASE link-- Why do model aircraft fly and maneuver so differently from real aircraft?

quiet flyer
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    I've noticed that certain features in an RC model may not be required aerodynamically, but the designer/builder includes them for realism. I'm amazed at the level of detail that some of these people achieve. – jwh20 Jan 10 '23 at 12:36
  • KE = 1/2 mv^2, but v is linear in m, so that's why KE varies with v^3 not v^2? – Camille Goudeseune Jan 10 '23 at 17:19
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    @CamilleGoudeseune -- I didn't realize until reading your comment that I had typed "cubed" instead of "squared", was simply an error-- – quiet flyer Jan 11 '23 at 12:59