2548 Official rules - scale tail feathers

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tfilemyr
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2548 Official rules - scale tail feathers

Post by tfilemyr »

I appologize if this subject has already been beat to death but I cant help noticing that all the planes I want to build have less than ideal tail moments. On the RCCA website it says 10% deviation but some of the posted pictures show what look like "sport scale" sized tailfeathers...

I did a bit of number crunching and found that typical (read famous) carrier based planes Zero, Hellcat, Corsair, etc, have huge scale tail surfaces and short moments. I guess its no wonder these are popular combat choices.

Likewise some of the more famous land based planes Me-109, FW-190D, Ki-61/100 all have tiny tail feathers offset by somewhat long moments. Im no expert but it seems these are somewhat of a disadvantage in r/c combat. (Some super small planes benefiting from huge scale factors seem to be an exception... you know who you are.) [;)]

Is the "new" provisional 2548 rules change supposed to address this by allowing larger (than 10%) scale deviation? Or is this already accepted practice in the interest of safety, etc? Im not looking for a rules bending freak. Im just feeling the infrequent urge to build something and want to see some Doras and Tonys in the fray. [:D]
wrnstockwel
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Post by wrnstockwel »

Along that theme, our Texas Flugwerks 3696 Zero flies and groves just fine (scale tail) while the FW190 for both 3696 and 2548 required a slightly larger than scale vertical and horizontal stabilizer, without exceeding the 10% rule, the difference is very noticable in performance. Our twins (P-70 and Me-110) have been using scale tail surfaces, without giving up anything in performance.

Just the nature of the beast I guess,
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Ed Kettler
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Post by Ed Kettler »

I don't want to go past 10% on the tails as it will start looking like my cartoon scale P-39s I fly in SSC.

You need to keep in mind that we are not looking for SSC furballing in 2548 ... the wing loading was designed to make it more scale like, more pursuit oriented.

The other factor on carrier based planes is they tend to have less taper in the wings and broad tips, making them less subject to tip stalls and snapping.

I fly 2548 P-51s with scale outlines (including the crank in the wing for the D models) and they fly fine with an engine running at 14,500 and at 3.25 pounds. I did fly a FW-190D with a longer tail moment (real plane had a 12" fuselage extension just forward of the tail cone) , and with a hard pull the tail would force a rotation harder than the wing wanted to pull for a smooth turn. I just maidened a FW-190A that flies great, but Scott cut the tail so he can fess up if it is not really scale.[:D]
Image
Image

Lots of choices out there, find something you like then build and test it
combatgoblin
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Post by combatgoblin »

3.1.2 Key Dimensions. Fuselages must be three-dimensional. Profile fuselages will not be
allowed. The maximum wingspan shall be 48"
tfilemyr
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Post by tfilemyr »

Yep. However, if Im reading this correctly the RCCA 2009.1 Provisional and the RCCA 2009 official (AMA?) rules appear to be different in handling deviation from scale outline.


RCCA Rules for Scale Combat (All Classes) Revised 27 January 2009

3.2 Aircraft must resemble their full-scale counterparts. Single engine models are to be scaled to a wingspan of no more than 48 inches and no less than 40 inches. Multiengine aircraft are to be 1/12th scale +/- 10%. All deviations from scale outline must be within ten (10) percent of each other and within ten (10) percent of scale, and retain scale shape and proportions. For example, scaling a model’s wingspan up 10% and the fuselage down 10% is not allowed. The deviations shall all be in the same direction (plus or minus); it is not permissible to scale some elements up and others down.

3.2.1 The Contest Director shall determine accuracy-of-scale by simple visual inspection at 15 feet and may, at his discretion, request from the pilot a three-view drawing or photo, to help in determining scale fidelity. The burden of proof of scale fidelity shall reside solely with the pilot of the aircraft.

//

RCCA 2548 2009 Provisional Rules v 2009.1 27 January 2009

3.1.2 Key Dimensions. Fuselages must be three-dimensional. Profile fuselages will not be allowed. The maximum wingspan shall be 48â€
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Ed Kettler
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Post by Ed Kettler »

The AMA rules are for 2610 which allows 10% deviation (in other words, measurable). 2548 has no set deviation range, it has to look like the original plane ("closely match" = qualitative); the approach has its pros and cons. What we don't want are people overly manipulating the plane for competitive advantage.

The right answer is based on which event you are flying. We fly 2548 in North Texas, and I have enough guys that can recognize something that is "off". So far, nobody has brought a "what the heck is that" to a contest here, and I have not disqualified anybody, nor have I heard of anybody being disqualified.
Lee Liddle
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Post by Lee Liddle »

In a nut shell, currently, AMA rules for "all scale classes" do not apply to 2548 because it is not an AMA rulebook event. Keep it close to scale. Enlarge the tail feathers a little if you need to. Just keep it "looking right" and have fun.
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Post by THend »

Just build and fly a highly recognizable WWII AD1 SkyRaider...with Lee's dimensions....

You'll be fine..[:o)]
Lee Liddle
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Post by Lee Liddle »

At least the AD1 is on "The List"

BTW my tailfeathers are within 10%, eventhough there is no rule stating that they have to be.
THend
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Post by THend »

Yup, it is on the list and it has great dimensions and an already appropriately sized scale tail that is great for combat. Plenty of area on the vert...and the moments are right on.. a dead on winner.

Now, if a plane does have a longer moment with a smaller empennage technically would be somewhat similar to a shorter moment with larger empennage give or take to some degree. But you want authority when there are streamers out on the wingtips...hence better to have long moment and larger emmpennage.

So the AD1 Sky Raider built to Lees specs is a winner and will be accepted by those flying 2548, and it capitalizes on a longer moment AND larger emmpennage... I am pretty sure it would suit 2610 too.

Why would I not suggest to everyone to fly that plane? Like you said, it is on the list of highly recognized WWII combat planes, and you can build it to scale with no worry of deviation...pretty simple outline with plenty of wing area. It is the new Ta-152..everyone should have one.

It is a winner, and you put it there. I guess I could have told the guy to just build an AD1 Sky Raider and leave it at that...just tell him to have a go at it.

Your last comment wasn't very cool, but what else would I expect...

You guys rationalized putting it on the list, I rationalize poking fun at it....and the others that don't belong on the list.

We all rationalize..

It goes round and round...
cosmo64
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Post by cosmo64 »

I still am trying to figure out how the skyraider made the list..I do not see how it meets the criteria of A.3....

If it does please educate me...I think I am pretty saavy on WWII aircraft..Only prototypes produced prior to '46...actived duty started in '49

IMHO...looks like a ringer

Stir...stir...stir
THend
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Post by THend »

Sorry tfilemyr for the off subject sidebar hijack...

I would highly recommend building whatever plane you choose to fit the class of combat you will be flying. It may be a good idea to whittle in on what is considered "close enough". If it is 2610, follow the rules, if it is 2548 maybe peer check with others that fly 2548 for acceptability.

The Sky Raider...
It is a great plane, Lee is a great guy and leader in RC Combat, and even if I was of the original 2548 crew and flew with those guys every weekend, went to their kids birthday parties etc.. I would still poke fun at the Sky Raider being on the list.....

Maybe I am the only one who sees the humor in it... Wouldn't be a first. I apologize if I ruffled any feathers, I take 2548 very tongue in cheek...and I didn't take into consideration the feelings of you guys who fostered the class.

My comment wasn't intended to be hurtful at all in any way, sure some poking but not intended to foster ill will.

Just like one of my bestest best combat flying buddies has to go up and see if he can flat spin and snap roll his combat plane... I poke fun at him too, regularly..... because it doesn't add up in my book, and I think it is funny.

BTW, saw the doctor yesterday and I was told "no more snacking"....[:o)]
Lee Liddle
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Post by Lee Liddle »

Glen, the criteria for being on the list are pretty simple. They are.....
Lee Liddle wrote:........... of a single or twin piston engined aircraft
- that flew prior to 1946
- that saw air-to-air combat or active squadron service at some point
(including after 1945)
First flights of the AD-1 were in the Summer of 1945, so it flew prior to 1946.

It flew air to air combat in Korea and Southeast Asia, with well documented air to air kills. Even kills on Migs.

So those are the requirements, and it meets the requirements.
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Post by Lee Liddle »

Terry, it`s all good. I just followed Pete`s lead. As much grief as I`ve given you about the Manta over the years, you have every right to poke fun of the AD-1. It doesn`t bother me at all, really.

I like the plane because it flies great and is a piece of cake to build, and has plenty of room for batteries and esc. I fudge the specs here and there, no doubt, but it would still fly great as a dead nuts 100% scale combat plane.

As far as "The List" goes, look for a few new additions for next year. Just for fun.[;)]
cosmo64
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Post by cosmo64 »

Lee,

I guess my beef then is that the statement in parenthesis (including after 1945). This statement appears to be an afterthought to the rule to allow an airplane that somebody already had designed and wanted to use in this provisional class. There are'nt many airplanes in this category. Even the TA-152 saw action in WWII.

I do not think that the Skyraider would have a significant advantage over any other WWII aircraft and it would be a fine aircraft to model for all the reasons you stated. But...If 2548 is to be for WWII aircraft then it should be for aircraft that actually saw combat in WWII.

I am sorry for the thread getting hijacked...
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