Large scale RC planes. | Forums

[RedToo]

One or two are so big you would have thought they could build a real plane:

http://www.flixxy.com/international-...-show-2011.htm

Redtoo.

[Crazy_Goanna]

Some very nicely built planes there
thanks for the link Redtoo!!

[Cajun76]

Awesome! Was that a model of a real plane around the 2:00 mark? The low, forward front wing had landing gear, and the rear wing was high and at the midpoint of the fuselage, and the tail only had the rudder. Interesting bird. The 109 landed quite realistically.

[Cajun76]

I also wonder about how some of these faithful replicas fly when the real things are a bit unstable and require digital fly-by-wire controls and computers. The Nighthawk and Viper come to mind.

[AndyJWest]

Cajun, I think the tandem-wing model was a Rutan Quickie http://en.wikipedia.org/wiki/Rutan_Quickie, or one of the developments from it. Regarding stability, to a certain extent this depends on the centre of gravity, and you can move it forward a bit in a model, for stability at the expense of manoeuvrability.

Some amazing models there - though why anyone would build an R/C Piper Cub that big, when building a real one would take little more effort, is beyond me...

[Choctaw111]

Thanks for the link. I really enjoyed watching that.
Having flown RC models for many years I can really appreciate the large scale models BUT still can't understand why someone would spend so much money for a large scale model that only has a single or twin engine. The 109 flyby near the 2 minute mark is a good example.
The scale appearance is good but the sound is embarrassing.
There are some V type scale engines out there today and there are plenty of radial engines to choose from.
A big part of why I like the WW2 era planes is because they sound so awesome!

[voyager_663rd]

I also wonder about how some of these faithful replicas fly when the real things are a bit unstable and require digital fly-by-wire controls and computers. The Nighthawk and Viper come to mind.

Because there are certain concessions made in the build to allow for a more stable experience. Corsair comes to mind: compare the rudder shape on a model to the real bird. Big difference. Surface area (wing, stab) can also be increased to provide a more stable flight.

Giant scale is a single wing with w.s. of +80inches and for a bipe 60". It does NOT have to conform to the real plane as far as dimensions, surface area, etc.

In scale competitions, plane outline and markings and other smaller detail (c.ock pit panel for example--gol durn language police) are of key importance but if you were in a "stand-off scale" competition, that is different again (as opposed to "scale" competitions)--less stringent requirements.

[Cajun76]

Cajun, I think the tandem-wing model was a Rutan Quickie http://en.wikipedia.org/wiki/Rutan_Quickie, or one of the developments from it. Regarding stability, to a certain extent this depends on the centre of gravity, and you can move it forward a bit in a model, for stability at the expense of manoeuvrability.

Some amazing models there - though why anyone would build an R/C Piper Cub that big, when building a real one would take little more effort, is beyond me...

Thanks, looks like a Quickie to me too. Reminds me of a dragonfly, which, as insects go, are my favorite to watch as the zip around, hover and maneuver in all directions effortlessly.

I was actually referring to the inherent aerodynamic instability built into the F-16 to make it more maneuverable: negative stability. I'm not sure if a simple weight transfer in a faithful replica would solve that. I suspect the elements that contribute to the instability have been slightly altered to provide positive stability.

The F-16 was the first production fighter aircraft intentionally designed to be slightly aerodynamically unstable, also known as "relaxed static stability" (RSS), to improve maneuverability. ... Aircraft with negative stability are designed to deviate from controlled flight and thus be more maneuverable.

I have to disagree about constructing a real Piper taking just a little more effort than a large R/C though. Just the instrumenting and radios alone puts the price much higher, as well as the structure being different to accommodate pilot, passengers and/or cargo. Pesky humans and cargo are also usually in the way of the most efficient layout for the control linkages and cables. The scale is not where the effort lies except external details. It's the bits that accommodate a real pilot that would significantly impact the differences between a large model and the real thing.

This is similar to the post about some Spitfire replicas being 90% scale or so. Some wondered why not build full scale, even though part of the point of the project was to make replicas that were less expensive and more accessible. The replicas don't need to carry a combat load at 400mph and 20,000 feet, so they don't need quite as big an engine, or as long a span to carry a smaller engine and no guns and ammo. If they keep the heritage alive, that's what matters to me. A kid watching his first Spitfire zoom by and getting the fire in his belly for aviation won't really care if it's 10% smaller.

[Cajun76]

Because there are certain concessions made in the build to allow for a more stable experience. Corsair comes to mind: compare the rudder shape on a model to the real bird. Big difference. Surface area (wing, stab) can also be increased to provide a more stable flight.

Giant scale is a single wing with w.s. of +80inches and for a bipe 60". It does NOT have to conform to the real plane as far as dimensions, surface area, etc.

In scale competitions, plane outline and markings and other smaller detail (c.ock pit panel for example--gol durn language police) are of key importance but if you were in a "stand-off scale" competition, that is different again (as opposed to "scale" competitions)--less stringent requirements.

Makes sense to me.

[Luno13]

Some amazing models there - though why anyone would build an R/C Piper Cub that big, when building a real one would take little more effort, is beyond me...

Insurance companies...FAA...