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Author Topic: Best Stunt Ship  (Read 8795 times)

Offline Motorman

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Best Stunt Ship
« on: November 28, 2012, 10:49:49 PM »
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« Last Edit: September 03, 2021, 11:56:30 AM by Motorman »

Offline Clint Ormosen

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Re: Best Stunt Ship
« Reply #1 on: November 28, 2012, 11:13:42 PM »
The latter.
-Clint-

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Offline wwwarbird

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Re: Best Stunt Ship
« Reply #2 on: November 28, 2012, 11:27:10 PM »

 You may want to check Clint's "Forum Realities" post on this one. ;D
Narrowly averting disaster since 1964! 

Wayne Willey
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Offline dankar

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Re: Best Stunt Ship
« Reply #3 on: November 29, 2012, 08:47:58 AM »
Right on Ty !

Offline Howard Rush

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Re: Best Stunt Ship
« Reply #4 on: November 29, 2012, 11:14:00 AM »
So, after decades of stunt flying have we identified the best design, is there a formula for surface area/moment arm ect. or, is it one of those things where a wide variety of things will work just as well?

We're still looking for the best combination, but I don't think the "numbers" are a particularly useful way to look at the problem.  People use the same concept to pick women.  It leaves out some parameters.
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Online Brett Buck

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Re: Best Stunt Ship
« Reply #5 on: November 29, 2012, 11:24:02 AM »
So, after decades of stunt flying have we identified the best design, is there a formula for surface area/moment arm ect. or, is it one of those things where a wide variety of things will work just as well?

     There is a fairly narrow range of parameters that have been arrived at that appears to provide the best performance. Look at some currently competitive airplanes  (SV-11 and similar airplanes, Impact, Trivial Pursuit, Geobolt, etc) and you will see that they are very similar. The arguments you see are over very minor details - no one is doing anything radically different from anyone else. All of these ideas were arrived at in the early/mid-90s to take advantage of superior power available.

   A wide variety of things will NOT work just as well, depending on your definition of "wide". I consider all the current competitive airplanes are in a very narrow range of variation. There are no exotic designs, canards, biplanes, etc. The biggest differences are things like (for example) the aspect ratio of the stabilizer, I think the SV-11 and similar have too high an aspect ratio tail, Randy et. al would undoubtedly argue that mine is too low and either one could be right. But we are talking the difference between a 6:1 and 4.5:1, we aren't debating to any degree what the far more important factors are, like the tail moment or the tail volume coefficient, almost all of them are within a few inches and within a very narrow range of about .4 to .5 or so. Everything else is like that too, we don't discuss the gross numbers anymore because we all agree.

      One the airplane design side, there have been about two important changes since the Nobler was designed in ~1951 - more tail volume and thicker/blunter wings. In *60* years that's about it. There are a bunch of details that make noticable difference but in terms of raw, big-picture design numbers, there isn't any significant debate on what works.

    The details of the engine/motor setup make far more difference than the airplane design, and there have far bigger and more recent changes.

     Brett

Online Tim Wescott

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Re: Best Stunt Ship
« Reply #6 on: November 29, 2012, 11:26:39 AM »
So, after decades of stunt flying have we identified the best design, is there a formula for surface area/moment arm ect. or, is it one of those things where a wide variety of things will work just as well?

The "Moitle".  But then those sneaks at the AMA went and changed the rules so it's not competitive any more.
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Online Brett Buck

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Re: Best Stunt Ship
« Reply #7 on: November 29, 2012, 11:32:32 AM »
The "Moitle".  But then those sneaks at the AMA went and changed the rules so it's not competitive any more.

???   You can build a Moitle anyway you want, fly it any way you want, and as far as I know there are no rules that make it impractical. Good luck going up against Paul Walker.

    Brett

Online Dave_Trible

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Re: Best Stunt Ship
« Reply #8 on: November 29, 2012, 11:41:11 AM »
So, after decades of stunt flying have we identified the best design, is there a formula for surface area/moment arm ect. or, is it one of those things where a wide variety of things will work just as well?

Thanks,
MM
For an interesting exercise take the Shark 45 plans and compare to todays designs.  Add a bit more tail area,  modern adjustables and a piped .51-.65 and you'll be pretty competitive.  Mostly I think its about grooming a design to fit your style and liking.

Dave

I still need to check out Howard's dating service.
« Last Edit: November 29, 2012, 01:54:25 PM by Dave_Trible »
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Offline Allan Perret

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Re: Best Stunt Ship
« Reply #9 on: November 29, 2012, 02:04:58 PM »
    But we are talking the difference between a 6:1 and 4.5:1, we aren't debating to any degree what the far more important factors are, like the tail moment or the tail volume coefficient, almost all of them are within a few inches and within a very narrow range of about .4 to .5 or so.
What is the definition / formula of the "tail volume coefficient" ? 
Mostly trying to understand if this measurement takes into account the tail moment arm, or is just a ratio of wing and tail areas 
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Offline Howard Rush

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Re: Best Stunt Ship
« Reply #10 on: November 29, 2012, 02:11:56 PM »
Here's a good writeup: http://www.eaa62.org/technotes/tail.htm .  It does take into account the tail moment arm and divides it by wing mean aerodynamic chord to make it nondimensional.  Tail volume coefficient is still a little too simplistic: it doesn't take aspect ratios into account, even though they are easy to measure.
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Offline MarcusCordeiro

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Re: Best Stunt Ship
« Reply #11 on: November 29, 2012, 02:50:14 PM »
I think this is kind like trying to get the best player in some ball sport, or the best driver ever.
There are many issues, but it all comes down to your favorite.
Maybe some like the Nobler, but will not tell, it's such an old ship, isn't it?
I'm about to get started on a Thundergazer, 'cause I liked he looks, and of course, it's a very good model.
But my favorite, and with a bit of luck, my next year's main building goal is Bill Simmons's Rogue...

Which is better

'69 454 Camaro Rs or '69 429 Boss Mustang?
2012 Camaro or 2012 Mustang?
I guess it depends on the way you like to drive.

Me? '69 Plymoth Roadrunner superbird...

Marcus
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Offline Douglas Ames

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Re: Best Stunt Ship
« Reply #12 on: November 29, 2012, 03:00:25 PM »

Which is better

'69 454 Camaro Rs or '69 429 Boss Mustang?
2012 Camaro or 2012 Mustang?
I guess it depends on the way you like to drive.

Me? '69 Plymoth Roadrunner superbird...

Marcus

Big Block musclecars from the past handled like pigs and braked even worse. The Boss 302 and Small block Z28 were decent for their time.

I currently own a 207 Shelby GT500 which blows away any past era Mustang.

Like others have said, "Best Stunt plane" is relative to the era  it was designed and flown.
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Offline Allan Perret

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Re: Best Stunt Ship
« Reply #13 on: November 29, 2012, 03:16:49 PM »
Here's a good writeup: http://www.eaa62.org/technotes/tail.htm .  It does take into account the tail moment arm and divides it by wing mean aerodynamic chord to make it nondimensional.  Tail volume coefficient is still a little too simplistic: it doesn't take aspect ratios into account, even though they are easy to measure.
Thanks for the link Howard.  Most interesting thing I learned it that TVC has application to all planes.  
For some reason I was thinking it was unique to c/l stunt because of the non-standard flap functioning.  
So what are some typical TVC numbers that work good for c/l stunt ?  

Also,  from the link  "SH = horizontal tail area"  ,   this is total area of stab plus elevator, right ?
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Offline Don Hutchinson AMA5402

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Re: Best Stunt Ship
« Reply #14 on: November 29, 2012, 03:39:17 PM »
Regarding "Moitle", she was designed and flown in 1944 and there were no stunt rules back then. The first itieration of stunt rules was used at the 1946 Wichita Nats and they were nothing at all like the OTS rules we fly to today. "Moitle' by the way is a very nice flying OTS airplane, leastways my first one ten years ago was, I now have another in the hopper for a spark ignition Torp 32, hope it is the same!. I am sure "Moitle" was the first model to use a symetrical airfoil and able to do outside maneuvers. Francis Reynolds, the designer was a very bright guy!

Online Tim Wescott

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Re: Best Stunt Ship
« Reply #15 on: November 29, 2012, 03:43:40 PM »
Modern stunt ships seem to favor a TVC of 0.5 or so.

But if it were just TVC, then a teeny tail on a long stick would fly just as well as a huge tail on a short moment arm -- but you don't see any long-moment, little-tailed stunters out there.  So there's got to be more to it than TVC (and even, for that matter, wing and tail aspect ratios).
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Online Tim Wescott

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Re: Best Stunt Ship
« Reply #16 on: November 29, 2012, 03:48:37 PM »
Regarding "Moitle", she was designed and flown in 1944 and there were no stunt rules back then. The first itieration of stunt rules was used at the 1946 Wichita Nats and they were nothing at all like the OTS rules we fly to today. "Moitle' by the way is a very nice flying OTS airplane, leastways my first one ten years ago was, I now have another in the hopper for a spark ignition Torp 32, hope it is the same!. I am sure "Moitle" was the first model to use a symetrical airfoil and able to do outside maneuvers. Francis Reynolds, the designer was a very bright guy!

Hah!  You make my point!  The ultimate ship arrived early, and then two years later they went and made rules just because of it!

(Moitle is on my long "to build" list -- but at the rate I build, the sun just may go out before I get around to it).

Sigh. My comments were a joke! I am thinking it would be a lot easier all the way 'round if youse guys would elevate your appreciation of humor, 'cos there is no way I will reduce myself to using those faggoty smiley things!

(Quoted because I couldn't say it better.  And besides, if I just repeated it, Dan would accuse me of copyright infringement)
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Offline Howard Rush

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Re: Best Stunt Ship
« Reply #17 on: November 29, 2012, 04:00:09 PM »
But if it were just TVC, then a teeny tail on a long stick would fly just as well as a huge tail on a short moment arm -- but you don't see any long-moment, little-tailed stunters out there.  So there's got to be more to it than TVC (and even, for that matter, wing and tail aspect ratios).

Yes, there is, and I should have mentioned the other stuff.  The first 9 items in the list of 10 in post 36 of http://stunthanger.com/smf/index.php?topic=20427.msg199505#msg199505 are some of the other things. 
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Offline MarcusCordeiro

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Re: Best Stunt Ship
« Reply #18 on: November 29, 2012, 04:08:05 PM »
Big Block musclecars from the past handled like pigs and braked even worse. The Boss 302 and Small block Z28 were decent for their time.

I currently own a 207 Shelby GT500 which blows away any past era Mustang.

Like others have said, "Best Stunt plane" is relative to the era  it was designed and flown.

That's my point exactly...
They were more fun to drive, taking to the limit all the time... VD~


marcus
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Action is his reward, look out
Here comes Marcus, man..."

Offline Howard Rush

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Re: Best Stunt Ship
« Reply #19 on: November 29, 2012, 04:12:43 PM »
Also,  from the link  "SH = horizontal tail area"  ,   this is total area of stab plus elevator, right ?

Yes, and the wing includes the flaps.
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Offline wwwarbird

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Re: Best Stunt Ship
« Reply #20 on: November 29, 2012, 04:40:16 PM »
Tail volume coefficient is still a little too simplistic: it doesn't take aspect ratios into account, even though they are easy to measure.

 Howard,

 I believe this concept has also been used to pick women, but again leaves out some parameters.
Narrowly averting disaster since 1964! 

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Offline Bob Hunt

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Re: Best Stunt Ship
« Reply #21 on: November 29, 2012, 05:36:34 PM »
The question was, what is the "Best Stunt Ship?"

That's simple: Mine!  LL~

Bob Hunt

Offline Howard Rush

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Re: Best Stunt Ship
« Reply #22 on: November 29, 2012, 06:15:35 PM »
I believe this concept has also been used to pick women, but again leaves out some parameters.

Reminds me.  I need a couple spinners.
The Jive Combat Team
Making combat and stunt great again

Offline Ted Fancher

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Re: Best Stunt Ship
« Reply #23 on: November 29, 2012, 06:51:49 PM »
Here's a good writeup: http://www.eaa62.org/technotes/tail.htm .  It does take into account the tail moment arm and divides it by wing mean aerodynamic chord to make it nondimensional.  Tail volume coefficient is still a little too simplistic: it doesn't take aspect ratios into account, even though they are easy to measure.

Howard's EAA link is a dandy one that may have been overlooked by some.  Not only does it give a good derivation of tail volumes but it also discusses the various "whys" of big versus small...a matter of no little discussion on these fora for the last decade or so.  I thought I'd cut and paste some of the pertinent pluses and minuses.  He also has a good picture of a pictorial method of determining the MAC (Mean Aerodynamic Chord) of a surface (yes, by the way a wing should always be considered including flaps and the tail including elevators when doing such things).  I've settled on using the phrase "average chord" vice MAC in my several thousand pages of blather about such things because it doesn't require much explanation and for any reasonable surface planform suitable for stunt will get the user into the right "ballpark" for the sorts of bench trimming we do to set up a new ship...usually refined by flight testing but that testing can be minimized greatly by paying attention to tail volume coefficient and the appropriate CG to accompany it.  Again, this sort of thing is the basis for my "wet finger in the air" method for determining an initial CG location when setting up for first flights.  It ain't rocket science but will get you in very close proximity of optimum and is pretty much guaranteed not to get you in trouble.  That method is simply dividing the area of the tail by the area of the wing, getting a 'percentage' and then locating the CG at that percentage aft of the MAC/average chord.  Tiny tails, tiny percentage aft.  Bigger tails, greater percentage aft (and reduced loads on the controls...see the writer's comments early in the following)

Ted

Here's the outtakes from the EAA document.  I've highlighted in green the "positive comments from our stunt perspective" and used red to highlight why we shouldn't let our tails get too small.  The purple is simply to  highlight the discussion of determining MAC which was accompanied in the link with a fine diagram.  That same diagram (or a reasonable replica) was included in my Model Aviation construction article for the Imitation that is viewable through the AMA web site if you want to go there.  Otherwise simply click on Howard's link.

Edited p.s.:  I did note when reviewing my post that the author (Stan Hall, my apologies for ripping off his stuff without crediting him) did address aspect ratio in passing in his brief discussion of regaining a stable setup by increasing tail area rather than moving the CG forward.  He suggests adding span because higher aspect ratios are more efficient (produce more lift per unit of drag when doing their jobs).  This may or may not be the best approach for a stunt ship, by the way, as Brett mentioned earlier.


"How Big The Tail
by
Stan Hall
Technical Advisor, Engineering, EAA Chapter
 62

In design, sizing the tail is a very subjective process, one which involves often conflicting requirements of c.g. range, stability, control and desired aircraft handling properties. Small tails tend to limit the permissible c.g.travel and thus yield low static stability, but on the plus side, yield low stick (or pedal) forces and low drag. Conversely, low-stability airplanes are harder to fly on instruments than higher-stability aircraft. For single-seat airplanes, however, the pluses of small tails sometimes outweigh the minuses. This is, however, the exception, not the rule.

On the other hand, airplanes carrying large tails provide a wider permissible c.g. range and tend to be more stable and thus easier to fly on instruments - but are often heavier on the controls, (depending on where the c.g. is). Large tails also produce more drag.

How, then, does a designer decide how big to make the tail on his new project? Unless he is a good mathematician and simply loves complicated arithmetic he will find what is known as the Tail Volume Coefficient much simpler to use, yet very effective.

The Tail Volume Coefficient is denoted by the letter V and is determined by one equation for the horizontal tail and another, quite similar one, for the vertical tail. The Tail Volume Coefficients relate the area of the surface, the distance that area is from the aircraft's c.g., the wing area, the mean aerodynamic wing chord and the wing span. Aircraft having the same Volume Coefficients tend to have similar static stability characteristics. Knowing this eases the design process.

In equation form Horizontal Tail Volume Coefficient (VH) looks like this.
VH = SH x LH / SW x m.a.c.
where SH = horizontal tail area, LH = distance from tail's aerodynamic center (more of which later) to the aircraft c.g., SW = wing area and m.a.c = the mean aerodynamic chord (more of this later, too)



Shown below is a sketch of how to determine the mean aerodynamic chord (m.a.c.) and the position of the aerodynamic center (a.c.) by graphical means. While the results are approximate they are considered accurate enough for the purposes discussed here. :'( :'(

Let me close by reciting a couple of old engineering bromides. (1) It is easy to design a tail that is too small. It is difficult to design one that is too large. (2) Big tails are more user friendly than small ones. Hint: Tailheaviness can often be cured simply by the addition of horizontal tail area. Adding it by increasing the tail span is more effective than adding it elsewhere because the tail aspect ratio is then increased, making it more efficient."
[/color]
©2000-2002 Stan Hall
Questions and Feedback can be sent to the webmaster



Online Crist Rigotti

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Re: Best Stunt Ship
« Reply #24 on: November 29, 2012, 07:48:49 PM »
The question was, what is the "Best Stunt Ship?"

That's simple: Mine!  LL~

Bob Hunt

You beat me to it! 
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Online Crist Rigotti

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Re: Best Stunt Ship
« Reply #25 on: November 29, 2012, 07:49:24 PM »
Reminds me.  I need a couple spinners.

Now that's funny!   LL~ LL~ LL~ LL~
Crist
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Offline Clint Ormosen

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Re: Best Stunt Ship
« Reply #26 on: November 29, 2012, 08:04:50 PM »

Which is better

'69 454 Camaro Rs or '69 429 Boss Mustang?



A '69 454 Camero? ???
I don't think there is one.
-Clint-

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Offline RandySmith

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Re: Best Stunt Ship
« Reply #27 on: November 29, 2012, 09:16:24 PM »

A '69 454 Camero? ???
I don't think there is one.

Biggest engine they put in was 396,  except for the very few COPOs that some had 427

R

Offline Clint Ormosen

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Re: Best Stunt Ship
« Reply #28 on: November 29, 2012, 09:47:15 PM »
Biggest engine they put in was 396,  except for the very few COPOs that some had 427

R


Right. Also some 427 Yenko Cameros, but those were dealer modified. Not factory.
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Offline Larry Fernandez

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Re: Best Stunt Ship
« Reply #29 on: November 29, 2012, 10:29:38 PM »


Which is better

'69 454 Camaro Rs or '69 429 Boss Mustang?
2012 Camaro or 2012 Mustang?
I guess it depends on the way you like to drive.

Me? '69 Plymoth Roadrunner superbird...

Marcus
[/quote]

Chevy didn't put 454's in camaros in 1969.

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Offline Larry Fernandez

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Re: Best Stunt Ship
« Reply #30 on: November 29, 2012, 10:41:53 PM »


Right. Also some 427 Yenko Cameros, but those were dealer modified. Not factory.

Actually, the 427's were installed at the factory. not all COPO cars were Yenko's.
Yenko took delivery of a few Copo 425 horse 427 Camaros (L-72), tweeked them a bit added the Yenko badging.
He also did some Chevelles, Novas, and Corvairs.
Any of these cars today, if properly restored, are worth well over 200K
I saw a Yenko Nova sell for 750K at the Mecum Auction a few months back.

Larry, Buttafucco Stunt Team

Offline wwwarbird

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Re: Best Stunt Ship
« Reply #31 on: November 29, 2012, 11:01:05 PM »
Reminds me.  I need a couple spinners.

 LL~ LL~ LL~ LL~ LL~
Narrowly averting disaster since 1964! 

Wayne Willey
Albert Lea, MN U.S.A. IC C/L Aircraft Modeler, Ex AMA member

Offline Igor Burger

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Re: Best Stunt Ship
« Reply #32 on: November 30, 2012, 01:02:33 AM »
Guys, you must remember that tail volume coefficient is good parameter of flat flying airplanes, but it is not enough for stunt airplanes. The reason is, that while normal airplanes has angle of attack on tail very close to constant (the same like wing), stunt airplanes fly radiuses, so angle of attack on tail is variable and can be +/- 20 degrees on our models. This makes difference between small tail on large arm and large tail on small arm. The difference is in effectiveness of airfoil of deflected elevator.

While short tail solution tends to have stronger and stronger pitching effect during tighter and tighter turn, long tail solution loses its effectiveness as model enters tight turn. So while short models can do tight but not so well controllable turns (so they need to be little nose heavy) long tails will show good initial movement but in reality they do not do 90deg turn so well and they need little more back CG.

So it is necessary first to find proper tail length which can keep initial moment to corner and effectiveness during turn in good balance (so the pilot can do clean and tight corner) and only then to play with area of the tail.

And second thing - larger tail volume can allow back CG, but too large tail and too back CG is also not good, especially if CG goes close or back of 25% of MAC. It is because too back CG can pust tail to produce positive lift, while maneuvering needs negative lift. Theoretically in clean air and perfect airfoils does not matter, but that transition from positive to negative lift in tiny inputs from pilot in level flight cannot do anything positive, I think it simply must lead to hunting, because quaily of flow is quicly changing in such conditions and so also microscopis change of deflection leads to large effect on such large area. My last model has tail area far over 25% of wing area (close to 30%) and CG is still front of 20%. However that large tail allows anything from 15 till 25% without too much difference :- ))

Offline Howard Rush

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Re: Best Stunt Ship
« Reply #33 on: November 30, 2012, 01:20:05 AM »
So it is necessary first to find proper tail length which can keep initial moment to corner and effectiveness during turn in good balance (so the pilot can do clean and tight corner) and only then to play with area of the tail.

Does the logarithmic flap linkage allow you to use a longer tail?
The Jive Combat Team
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Offline MarcusCordeiro

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Re: Best Stunt Ship
« Reply #34 on: November 30, 2012, 01:22:20 AM »
Guys

You are right, my bad here...
The 454 came in the Chevelle and Corvette.
The Camaro got the 396.
Anyway those cars were 100% muscle.
I got confused because one acquaintance is building a 69 Camaro with a fuel injected 454, and all the works
Blue and white. Mean machine..


Marcus
Live to fly, fly to live
Aces High!

"There's no try. Do or Do not." - Master Yoda

"Wealth and fame, he's ignorant
Action is his reward, look out
Here comes Marcus, man..."

Offline Igor Burger

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Re: Best Stunt Ship
« Reply #35 on: November 30, 2012, 01:29:07 AM »
No, it has nothing to do with flaps ... at least if I do not take its effect on aif flow deflection to the formula. If you want analyze what I wrote, you make loft curves for both configurations with deflected elevator before trasition to circular path and in the circular path. You will see that short and long tails are on different points.

Offline Igor Burger

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Re: Best Stunt Ship
« Reply #36 on: November 30, 2012, 01:45:29 AM »
I do not have coordinates of real tail airfoil, but here is NACA 0007 with 40% flap deflected to 30 degrees.

You can see that flap instantly deflected to 30 degrees before corner will cause separation. Negative angle of attack 5 degrees will push it to its maximum and negative angle 10 degrees or more again looses its effectiveness because low AoA.

So while short tail very close to wing when AoA of tail is only -5 degrees because of circular flow, will make tail more effective and it will want to do tight turns, tighter than the effect before model enters circular path. While too long tails will not be able to keep entered path because of too small deflection. Both can confuse pilot.

Well ... it is simplified, because I do not count AoA of wing, flap effect on air direction and deflection is also not really instant, but the main effect is clear from that description I thing.

BTW some people asked me why I use such small movable elevator. I think picture shows it well :- ))) .. just not to allow slying over critical AoA before corner. 

Offline Avaiojet

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Re: Best Stunt Ship
« Reply #37 on: November 30, 2012, 07:32:37 AM »
Is this design, Lou Wolgast's 'Pentastar,' a good performing model?

The kit is offered in two sizes.

Charles
Trump Derangement Syndrome. TDS. 
Avaiojet Derangement Syndrome. ADS.
Amazing how ignorance can get in the way of the learning process.
If you're Trolled, you know you're doing something right.  Alpha Mike Foxtrot. "No one has ever made a difference by being like everyone else."  Marcus Cordeiro, The "Mark of Excellence," you will not be forgotten. "No amount of evidence will ever persuade an idiot."- Mark Twain. I look at the Forum as a place to contribute and make friends, some view it as a Realm where they could be King.   Proverb 11.9  "With his mouth the Godless destroys his neighbor..."  "Perhaps the greatest challenge in modeling is to build a competitive control line stunter that looks like a real airplane." David McCellan, 1980.

Offline Bill Morell

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Re: Best Stunt Ship
« Reply #38 on: November 30, 2012, 08:19:29 AM »
Is this design, Lou Wolgast's 'Pentastar,' a good performing model?

The kit is offered in two sizes.

Charles

No, doesn't fly for s h i t. Eric traditionally kits planes based on lack of performance................. LL~ LL~ LL~ LL~
Bill Morell
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Offline Avaiojet

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Re: Best Stunt Ship
« Reply #39 on: November 30, 2012, 08:37:20 AM »
No, doesn't fly for s h i t. Eric traditionally kits planes based on lack of performance................. LL~ LL~ LL~ LL~

Bill,

Thanks for the humor.

Are you making fun of my dreams?   n~

Didn't know you could say  s h i t  on the Forum? Usually it looks like this S#*t.

IMHO, I think Lou Wolgast's 'Pentastar,' is the most attractive stunt model.

I googled 'Pentastar,' be interesting to know how the name came about?

Bill, thanks again for the humor!!

Charles
Trump Derangement Syndrome. TDS. 
Avaiojet Derangement Syndrome. ADS.
Amazing how ignorance can get in the way of the learning process.
If you're Trolled, you know you're doing something right.  Alpha Mike Foxtrot. "No one has ever made a difference by being like everyone else."  Marcus Cordeiro, The "Mark of Excellence," you will not be forgotten. "No amount of evidence will ever persuade an idiot."- Mark Twain. I look at the Forum as a place to contribute and make friends, some view it as a Realm where they could be King.   Proverb 11.9  "With his mouth the Godless destroys his neighbor..."  "Perhaps the greatest challenge in modeling is to build a competitive control line stunter that looks like a real airplane." David McCellan, 1980.

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Re: Best Stunt Ship
« Reply #40 on: November 30, 2012, 08:48:48 AM »
I wouldn't discount the psychological effects here. Some of us (should probably read most, myself included) usually convince ourselves that the best stunt ship in the world is the new one gassing off in the paint stand.

This effect is so strong that when we go put the maiden flight on this new bird, that we dare to put a full pattern on it just for bragging rights or because we mentally mask all the planes real inadequacieses.

Funny how a few flying sessions later, the posts start to roll in, asking trim questions about planes that "flew perfect, right of the bench".

I see this work in reverse too. Get to a contest, especially a pressure cooker like the Nat's, and oh, my world beater is flying like cr@p!  When in reality, its is flying the same as it always has, but our adrenaline is so high that we are super sensitized to every little nuance of what the plane is doing.

After a full week of intense flying at the Nat's, I once retrimmed my plane so that when I got home and took a month off of flying and finally got back to fly it, it felt extremely sensitive like a combat ship with explosive corners. At home I was yipping it all over and felt like an amature, where at the Nat's, I was "into it" from all the hours of flying every day and didn't give it a second thought and the plane felt rock solid. (Note: I left the plane alone, and learned to fly it that way. It only took a few flights to get back into it. And why put it back, and go through it all over again at the next Nats?)

Sometimes a little "top secret" confidence booster helps. Like some silly little modification you make and don't tell anyone about... "the airfoil varies somwhat from the plans, it's .00000000002% thicker at secret spot on the back side of the highpoint, bwaahahahahaha! I will dominate!!!!" or some such crazy thing. In reality, whatever effect such things have are probably lost in the noise, and certainly inside the building tolerance and capability of the average builder, but hey, if it give's you the confidence to walk out to pick up your handle with a little swagger and burn one in, I say why not. Heh heh.

So... while I know a "great" plane may be required to win a contest, I don't necessarily think you need the "best stunt ship" just one that YOU THINK is the best at that moment and have the confidence to drill through the tricks without choking.

Well, that's my silly .02 cents worth anyways.
EricV

Offline john e. holliday

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Re: Best Stunt Ship
« Reply #41 on: November 30, 2012, 09:46:50 AM »
If someone had really came up with the perfect stunt for everybody, why would that person come out with another design of the plane with minor changes.   I think and  still beleive the George Aldrich "Nobler" came the closest.  Look at how many planes have used the Nobler flying surfaces and moment arms.   I have had several that flew really well for me.   But, then I have had some that wound up being fun flying planes as they  will never fly well enough to really be competitive in  the stunt wars.   But, they were different and were built to prive some people wrong when I was told they would not do a stunt pattern.   Dick Sarpolous'   "Wild Goose" is one.   When I manage to get engine set right and weather helps, it will fly a recognizable stunt pattern.   If I really wanted to, I think it could use some changes to make it competitive, but, why as the judges would think it such a strange looking plane they would not give it the score it deserves.  My opinion as I have already had a judge tell me a certain plane I flew did not look right in the air doing the pattern.  In front of other judges it always score well.  But, that was his opinion and I thanked him for the comment.
John E. "DOC" Holliday
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Offline Larry Fernandez

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Re: Best Stunt Ship
« Reply #42 on: November 30, 2012, 10:55:49 AM »
[quote author=john e. holliday link=  My opinion as I have already had a judge tell me a certain plane I flew did not look right in the air doing the pattern.  In front of other judges it always score well. 
[/quote]

This individual should not be judging stunt.
Five foot bottoms are five foot bottoms, 45 degree tops are 45 degrees, intersections are merely tanget points. If you nail all of these and your loops are round and your squares are square, you should score well, no matter what the plane looks like in the air.
He needs to attend a couple of judging clinics if he wants to judge fairly.

Larry, Buttafucco Stunt Team

Online Brett Buck

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Re: Best Stunt Ship
« Reply #43 on: November 30, 2012, 11:04:52 AM »
[quote author=john e. holliday link=  My opinion as I have already had a judge tell me a certain plane I flew did not look right in the air doing the pattern.  In front of other judges it always score well.  


This individual should not be judging stunt.
Five foot bottoms are five foot bottoms, 45 degree tops are 45 degrees, intersections are merely tanget points. If you nail all of these and your loops are round and your squares are square, you should score well, no matter what the plane looks like in the air.
He needs to attend a couple of judging clinics if he wants to judge fairly.

Larry, Buttafucco Stunt Team

  The comment above could mean almost anything, from what you presume (that he was dinging him because it didn't look right) to "its' out of trim, looks bad in the air, and those out of trim conditions are causing you to make a lot of mistakes". I have probably said something similar myself, and I don't think I need to go to a judging clinic.

    You should never ever score the flight based on anything aside from the accuracy of the path it travels, but many times it is clear to the judges (who also tend to be more experienced pilots) that there is something wrong with the airplane that is making it more difficult or causing the mistakes, and it's not all that unusual to comment on it, at least at local contests.

    Brett
« Last Edit: November 01, 2015, 10:43:50 PM by Brett Buck »

Offline Randy Powell

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Re: Best Stunt Ship
« Reply #44 on: November 30, 2012, 11:07:07 AM »
I always love these "what is the best" conversations.

There is a performance design envelope that you have to stay in if you want a competitive ship. You can move outside of it, but you will be gain one thing and giving up something else. For instance, I built a lot of high aspect ratio designs. You gain a lightning corner and great groove but give up stability, particularly in turbulent conditions. Everything is a trade-off.
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Offline Shultzie

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Re: Best Stunt Ship
« Reply #45 on: November 30, 2012, 11:37:40 AM »
LOL![/b LL~  LL~ :!
After reading the discussions about best stunt ship....Hummmmmm!
 Wonder why the name and memories of that little BAAAAHUMMMMBUG! of Bob Baron's amazingly little high revin' 4 pitched prop'd .19 powered "combatish' looking stunt model waaaay back at the Olatha Kansas 68 nationals ...as it cut like a knife THROUGH THOSE MIDWEST SUMMA'TIME WINDS  with all the precision of a CLPA BRAIN SURGEON WITH TOTAL PERFECTION!

That little plane.....being flown BY BOB that DAY!!! (AT LEAST TO MY 2 PENNIES WORTH) IN MY FEEEEBLE' MIND....SHOULD HAVE EASILY TAKEN 1ST PLACE. H^^
Don Shultz

Online Tim Wescott

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Re: Best Stunt Ship
« Reply #46 on: November 30, 2012, 11:59:30 AM »
Well, what I'm asking is for someone to name one that does. Which design won the nats/worlds shouldn't they be considered the best. You guys pontificate too much. Just name a few planes that have the potential to win the nats next year.

Then you've changed what you were asking.  You asked which design is "best", and the answer (in amongst all the fruitful discussion about what makes "good") is that there is no "best".  That's it.  That's the answer to your original question.

There's a lot of good designs.  There is no best design.  What's best for me isn't what's best for you.  What's best for you isn't what's best for Paul Walker or Igor Burger, and I dare say (get out your stake and kindling) that what's best for Paul Walker or Igor Burger isn't what's best for you or me.  What's best for anyone this year may not be what's best for that same person next year.

As far as designs that won the Nats or Worlds -- well if you must have just one name for "best", then put the names of all the designs that have placed at Nats or Worlds in the last five years into a hat, pick one, and call that "best".  Then stand back and watch something else win the Nats this year.
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Online Brett Buck

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Re: Best Stunt Ship
« Reply #47 on: November 30, 2012, 12:02:04 PM »
Well, what I'm asking is for someone to name one that does. Which design won the nats/worlds shouldn't they be considered the best. You guys pontificate too much. Just name a few planes that have the potential to win the nats next year.

    I did. Understand that thread drift is a very positive feature.  

   Go look at the Trivial Pursuit, Impact and SV-11, those will be within a few percent in any measurable parameter of anything likely to win. That covers just about all the Walker Trophy winners in the last 30 or so years.

  There is essentially no serious debate among the contenders about what sort of airplane is most competitive and what the basic outline and dimensions might be. And at the level you are discussing there is no consequential variation, and it's most definitely NOT a matter of opinion or personal preference, as far as the type of parameters you are asking about.

 I would also contend it's not that much different at any level you look at it, but that is a different argument.

  But, again, you have to consider that the details that you are not asking about are critical, more important than slight variations on the dimensions that covers the entire range of competitive models.

   Brett

Offline Howard Rush

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Re: Best Stunt Ship
« Reply #48 on: November 30, 2012, 12:18:59 PM »
But, again, you have to consider that the details that you are not asking about are critical...

Amen, and not conveniently summarized.
The Jive Combat Team
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Offline Larry Fernandez

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Re: Best Stunt Ship
« Reply #49 on: November 30, 2012, 12:23:40 PM »
  The comment above could mean almost anything, from what you presume (that he was dinging him because it didn't look right) to "its' out of trim, looks bad in the air, and those out of trim conditions are causing you to make a lot of mistakes".

    Brett

     Brett

I completly agree. If the mistakes are there, they should be scored as such.
If the plane flies an accurate pattern, the pilot should not receive a lower score just because a judge didnt think the plane looked right to him.

Larry, Buttafucco Stunt Team


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