When I started to fly control line aerobatics I wanted to get as much information as possible. Being a rather curious individual I instantly subscribed to several model magazines. I ripped out all the page plans and collected them in a thick folder, in order to build them one fine day. I never did. But I used the drawings as reference for my own designs.      
As I’ve pointed out on another page of this website, I think the creative aspect is the greatest gift control line stunt can give us (even on my first “real” stunter, a Nobler, I couldn’t resist to apply a tiny modification). I’ve never developed one design through several versions to finally arrive at the maximum “Final Edition”. Each airplane had its own new design. On this route success sometimes fails to appear, but the urge to realize my own ideas has always prevailed. Thus those collected pages were a welcome help to decide on dimensions - which seem to be called “numbers” in our circles.      
        From conversations among flyers I get the impression that many of them just don’t dare to attempt their own design, and in several forums you can find those FAQs (frequently asked questions) about this topic. I do not expect a beginner to create a world beater, but anybody who has build an airplane from a kit or a plan should have some basic knowledge about what it takes to draw and construct a decent stunt airplane. A problem may arise when known dimensions have to be transferred to another engine respectively airplane size.      
                     
This is where those “numbers” come into play. After all, among us there’s probably not one single soul who has never "borrowed" a nice idea from here or a clever solution from there - there’s no need to reinvent the wheel !      
Since I’m so fascinated about the creative nature of our event, I’d like to encourage everybody to use available knowledge to his own advantage and come up with his own dream machine. For this purpose I’ve gathered some useful numbers and put into a table. In order not to exceed the patience of potential readers and the generosity of my server, I’ve concentrated on a small selection only. This selection includes airplanes which I consider TYPICAL for their size, engine capacity, and stunting capabilities. There are not only top class airplanes, but also examples of small size, profile construction, basic design, and a few cult designs. I’ve also added some samples of my own design where I didn’t find suitable material.
By using these numbers it shouldn’t be too difficult to draw a basic layout. Of course any desired change regarding engine size and weight (!) has to be considered, too. If for instance you intend to replace a Fox with a Super Tiger 46, you'll be well advised to reduce the fuselage nose length quite considerably or to increase the rear part of the fuselage. The first table will show the selected designs with a short explanation why I have chosen them.
      
                                   
GIGOLO was an attempt to find out how small you can get with a somewhat "serious" stunter. With a 2,5 ccm ( 15 ) size engine Gigolo flew better than expected and can hold its own in contests. Since it requires the same building efforts as a full grown PA model it's not recommended for beginners. I don't think that anything smaller can fulfill requirements for demanding levels of aerobatic flying.Span 106 cm.
Don Still's famous STUKA was originally flown with a Fox 29. A modern powerful 25 ( 4 ccm) should be a suitable, if not superior replacement. For those who want to stay within this capacity range - or dare to accept the challenge - this airplane size should be the right choice. Span 121 cm.
The BARNSTORMER is not an outstanding beauty. It represents the most popular 35 ( 6 ccm ) size airplane which is very easy to build. Simple box fuselage, simple wing construction without flaps, sheet tailplane. A capable design for those who want to enter the stunt scene, but yet don't like to fiddle around with more complicated construction details. Span 122 cm.
TWISTER represents the simple principle: profile fuselage, rectangular wing, sheet tailplane - but it has flaps! The most simple and cost effective entry into flapped aerobatics. Suitably powered by a Fox 35 or any other engine in that power range. In my eyes it's the perfect entry into serious stunt flying when efforts and risk should be kept low. Span 122 cm.
POLYGON was my first own design, built in 64. Basically it is a minimum stunt airplane ( like the Twister ) but with a built up fuselage. Upright engine may help to avoid a few engine problems for stunt beginners. The wing based undercarriage is for better looks. It's easier to try this feature in a rectangular wing than on a trapeze planform. Dimensions very similar to the Oriental. Span 124 cm.
ARES - a cult airplane! No need to spend any more words. Probably the most beautiful airplane ever created. Detroiter wing, 35 size engine. Construction and engine should be light !! Span 125 cm.
NOBLER - the father of all modern aerobatic airplanes. With classic dimensions which very often serve as a basic layout theme, even today (maybe today we prefer thicker wing sections). Also, even the construction methods are generally used. Span 128 cm.
UNITED - Bob Lampione's design of 72. In my eyes the perfect combination of simplicity,looks, and performance! Simple box type fuselage, trapeze wing planform, sheet tailplane, wing mounted undercarriage, cowled inverted engine - as simple as you can get for high performance! Even some modern, popular, and good stunt designs use this basic layout. 35 size engine. Span 132 cm.
ESCAPADE - one of my racer style designs. Those pretty cheek cowl are dummies, but they add a lot to optics. Inverted engine, fuselage mounted exchanchable gear. Typical 46 size airplane ( original had Super Tiger 46 or Jett 50 ).. Span 142 cm.
MAGNUM - the well known and popular SIG kit. Many were "customized" and served as a quick and easy way to get a satisfying stunter. 45 to 50 engines. Span 147 cm.
STILETTO - Les McDonald's 3 times World Championships Winner. Best selling control line model plan ever by Model Aviation magazine. The typical 46 size airplane. Regarding it's success rather simple construction. Span 146 cm.
SHARK - one of the first 45 size stunters, started the trend to this engine size.Trike gear. Span 148 cm.
DUETTO - my attempt to produce a competitive biplane. I wanted to find out: how well can a biplane fly. Probably not quite up to the level of highest performance stunters, yet it had some respectable success in contest circles. Designed for 46 size engines (original had Super Tiger 46). Flaps on both wings. Span 112 cm.
TRIVIAL PURSUIT - Ted Fancher's beautiful, successful, and world wide copied airplane. A typical 60 size design, but very often flown with bigger capacity engines recently. Span 152 cm.
M 35 - my (far from) semi scale model of the Messerschmitt M35 full size aerobatic craft. Since I believe in short (fuselage!) noses, the nose is kept as short as possible. Circular engine cowling, 60 engine. Span 156 cm.
CARDINAL - Windy Urtnovski's famous design. From my experience: everybody who has built the Cardinal has improved his flying considerably. Designed for 60 engines, it is flown with much bigger engines, too. It's a big model and needs a powerful engine. Span 157 cm.
 
In sketch 1 you’ll see which dimensions are given, and their designation. It is these dimensions which are the base of each design. I cannot claim these numbers to be 100% correct (more about this later). But they are the essential components to build upon, and are generally accepted, used, and published. These numbers work quite well as long as we talk about the typical aerobatic design with popular and traditional shape and proportions.
 

The next table shows which dimensions were taken and the definition of all numbers.

 
 
  Definition
1
 Wing area, including flaps, of course ( flaps are part of the wing )
2
 Weight, as far as known
3
 Tailplane area. Means: stabilizer plus elevator area
3
 Tailplane area in percentage of wing area
A
 Wingspan
B
 Dimension spinner backplate to wing nose ( at root )
C
 Wing chord at root
D
 Flap chord at root
E
 Dimension between hinge lines of Wing and tailplane
F
 Tailplane span
G
 Stabilizer chord ( at root )
H
 Elevator chord ( at root )
       

Right from the beginning let me state: some of these numbers may not be 100% correct! In most cases I had to calculate a multiplication factor to transfer the dimensions from a DIN A4 format ( those pages mentioned above) to full size. Sometimes these dimensions are difficult to take from the drawing, sometimes there are several versions of one design. I have worked as precise as my abilities allow. Wing area numbers were taken from printed information or calculated from existing plans. And finally - weight figures were asked from flyers who had built this design ( I’ve tried to give an “average” number).
  1 2 3 4 A B C D E F G H engine
Gigolo 20,5 675 5,7 27 106 16,2 18 5 30 48,5 8 6 15
Stuka 32 950 5,7 18 121 16,7 21,5 6,5 30 45,5 6,3 6,3 25-30
Barnstormer 29,7 900 5 17 122 16 20,5 (7) 31 46,5 6,5 6,5 35
Twister 31 1300 5,4 17 122 19,5 21 6 34 46 7,6 6,7 35
Polygon 31,8 1250 5,5 17 124 22 21,5 7 33,5 50 7,5 6,5 35
Ares 32,4 950 5,1 16 125 22,5 24 7,5 34,5 55 5,5 7 35
Nobler 35,6 1100 6,7 18 128 21,5 25,5 7,2 36 50 7,7 7,7 35
United 39 1380 6,6 17 132 23,5 26,5 7,3 36,8 52,5 7,6 7,4 35
Escapade 40,5 1650 10 25 142 24,5 25,5 7,5 43 66 9,5 9 46
Magnum 45 1750 10 25 147 25,5 27 8,4 42 70 8,5 8,5 46
Stiletto 42,6 1600 8 19 146 26,5 26,5 7,5 43 70 7 7 46
Shark 42,9 1800 8,8 20 148 26,5 27,5 7,5 46 60 12 9,5 46-50
Duetto 41,4 1750 7,9 19 112 19 15,5 3,5 48 58 10 8 46
Trivial Pursuit 43 1870 10,9 26 152 25,5 26 7 46,5 65 11 9 60+
M 35 42 1750 10,7 25 156 23 26 7 46,5 72 10 8 60
Cardinal 44,5 1850 12,7 28 157 28,5 27 8,5 46,5 79 11,5 10 60+
 
Measurements in the table are given in decimal numbers. For those trapped in the Imperial world here are the conversion factors:
all dimensions in Centimeter times 0,3937 = Inches
wing area in Square Decimeter times 15,5 = Square inches
Weight in Gramm times 0,0353 = Ounces
 
                           
Now I can already see that some experts’ hairs stand on end. This ominous dimension “E”! It doesn’t really take into account wing and/or tailplane shape. Oh, I know. I’m fully aware that this information is totally incorrect. It shouldn’t be the dimension between hinge lines. Aerodynamically correct it should be the distance between the location of ACs (Aerodynamic Center, chordwise ) of wing and tailplane. Alas this is never marked on plans, has to be figured out ( somewhat complicated ), and probably a few people don't know about it and how to define it. For the majority of flyers (including me!) I feel this number is a little less than absolutely decisive. As long as we have to deal with usual traditional shapes, dimension E as given in the table is throughout appropriate.
In sketch 2 you can see the problem. As soon as the wing and/or tailplane planform differs considerably from common shape, it’s quite obvious that the simple hinge-to-hinge rule doesn’t work any more. In such a case (like for instance Jack Sheeks’ “Freedom” design) we really have to go to the trouble and find out AC locations. I’ll try to give a detailed explanation on another page - as soon as time (or laziness !) permits.
  An additional problem arises when we consider a biplane design - especially if we are inclined to swept wings - staggered !!! For my biplane design I’ve assumed an average lengthwise location of an imaginary wing, positioned right in the middle between both actual wings, and measured the B and that dreaded E dimension. I hope you’ll forgive me for this unconventional method.
One last thought. The full task of designing an airplane right from the beginning cannot be done by just choosing several measurements and combining these "numbers" on an empty sheet of paper. Parameters like aspect ratio, moment arm, or tail volume are formulas which are not given in Centimeter or Inch. However I don't think that the occasional "designer" wants to delve into aerodynamics that deeply. So, these commonly used numbers should be a quick and easy reference to be used as a data collection to base our own creation on.