Your opinions please

N'uther thread today was asking about the !QUOT!best!QUOT! F-6F. I commented that the Wing kit was a great flyer but way off in scale. They state that the kit is 1-3/8 inches equals one foot. The kit ends up with a 61 inch wing and 44 inch fuselage. For the stated !QUOT!precision!QUOT! scale kit the wing is 103% too big and the fuse is 95% of what it should be.

The plastic building folks go ballistic if a plastic kit doesn't scale out exactly to the stated mm.

So how far off from a stated scale can a scale model be and still be a scale model of the original subject?

Maj. Tom
USAFR ret etc.

When I built my first real airplane I checked what the factories were up to.
A 150 was several inches out of square. I add up the tolerances and a big aircraft will vary in feet .
Darryl Usher

Wing Mfg advertises their short-kits as "Sport" Scale. That means they closely resemble a real aircraft in outline and porportions.

A scale kit should have an accurate outline, no two airplanes are identical inch to inch, But the kit should not radically change the outline, wing dihedral, engine placement, canopy shape from the true outline. The relative ratio between span and length should be same as the full size airplane. If the model is 1/8 scale the fuselage should be 1/8 of the full size and wing should be 1/8 size. All dimensions should be 1/8 of the full size airplane.

Several examples of things not to do (I have plans that have done this)

DC-3 pushed the engines outboard to gain prop clearance to the fuselage, yet did not change wingspan
B-29 push the wing back to improve CG location, nose was too long, tail was too short
enlarge elevator to improve stability yet wing and fuselage is normal size

When you read the rules for scale competition they judge several things:

1) scale outline
2) Markings
3) Color scheme

1) - don't change outline it sticks out like a sore thumb when compared to a 3-view
2) - don't change markings from full size, must match full size letter for letter
3) - Paint scheme must match full size being copied, color for color

Just my thoughts on this
Fred Cronenwett

the scale will change with whatever you have for documentation. So scale is what your documentation says it is. You match your three views then you are scale. The problem you will find is that alot of documentation does not match . It all depends upon the source that was used. So on to the practical side of things. My eye can spot a deviation in outline a mile away. It just stands out so once my eye sees it, its only funscale. Make sense?, probably not.

quote]ORIGINAL: TLH101

Wing Mfg advertises their short-kits as !QUOT!Sport!QUOT! Scale. That means they closely resemble a real aircraft in outline and porportions.
[/quote]

Sorry Terry but Wing lists the Hellcat as PRO scale kit which from the wing add means "The pro kits have everything that the experienced builder/flyer needs to build an exact scale of some famous aircraft. "

My experience with this one kit is that there was nothing "exact" about it. My intent is not to bash wing, just get a feel for how inaccurate can a scale model can be before it becomes sport scale?

You ask a difficult question. I think your poll does not provide enough information to get usable results. In other words, it's a rather ambiguous question. I think you will get similar results.

For instance, if a model had a 100% accurate outline, but lacked any details what-so-ever, including a painted over canopy, it might be sold as a fun scale airplane. So, in my mind, scale has much to do with the detailing.

Imagine entering Top Gun with a perfect outline airplane. It's painted in perfect colors but lacks any detail what-so-ever. Then compare it to an airplane that deviates somewhat in outline. But this second airplane is detailed to incredible museum quality. Every rivet, seatbelt, smudge mark etc. is done to amazing quality. Which one would win Top Gun (or some AMA scale contest maybe) to the letter of the law? Which one would win, considering humans do the judging? Which one would be more impressive?

I would consider both airplanes to be scale airplanes. But they would be scale for different reasons. I would prefer the one with the hundresds of hours of extra labor. Certainly, the simple looking airplane would quickly become "un-scale" very rapidly if it's outline started to deviate from perfect. The highly detailed airplane can get farther away from perfect outline before it became "un-scale".

That is why I feel the poll question is difficult to answer. It just lacks enough "what-if" information. By the way, a scale airplane is a "scale airplane" if it resembles the full scale version. Is that a P-51? Sure it is, if it looks like one. But I don't think that is what you likely meant by the original question.

Wait, there is more! What if I score a 50 for static at an AMA scale meet? Is it scale or not? How many percent from scale outline does that make it? For that matter what if my Corsair is painted the wrong color but the outline is dead on?

What a messy thing, this scale question. I personally being somewhat unknowing on the complete AMA (and others) rules on scale would love for an expert to share some thoughts on this subject.

Chuck

The AMA scale rules can be downloade to a computer near you. Even to your desk top! Look at the AMA website and then look at the downloads and then "Scale". All the information you desire is right there. The USSMA (Scale Masters) also publish their competition giude for downloading as does Frank Tiano (Top Gun). Regards BobH.

Major, One other factor is what three view were you using to compare the Wing kit too? Just like G-man said, you can get six three veiws from different sources and none of them will match perfectly. Don

This is a very interesting poll! As it stands at this moment;

A scale model has outlines that are off by no more than 10% 32% (10)

It's a scale model if it looks like the prototype no matter how off. 12% (4)


While ChOpp3r brings up some valid discussion points, this question strictly pertains to the scale outline.
It appears that the IMAC 10% deviation and "scale" combat deviation from scale rules may have had an impact on perception of what scale is.

I find it particularly interesting that 12% don't care how far off it is...they would still call it scale.

Don, I started with the most basic of data, the published wingspan and length for the Grumman F-6F. I checked multiple sources such as Janes, the internet and US Naval Fighters. Convert these dimensions to inches then multiply by 1.375 the pro ported scale used by Wing. Then compare these to the finished dimensions of the kit. The wingspan is too long and the fuselage is short. That's why my poll is so simple. There are multiple discussions of fit, finish and color accuracy, but what good are these if the airplane doesn't' have the correct outline, or the reverse can all of these make up for an inaccurate outline?for an inaccuate outline?

I have the Wing kit and the wingspan you mentioned is 61" but the length according to the plan is 46.5". Using the Kokofan three view provided the fuselage should be 47.2". So that is close to being correct according to the three view. I think you measured from the front of the cowling instead of to the front of the prop dome. Almost all full scale manufacturers measure from the prop dome not the fuselage itself. According to the figures the fuselage is 98.5% of what it should be .

Hal

Major, I am a real stickler when it comes to outline myself. A less than 5% deviation shouldn't be too noticable on the model. More noticable to me are thick non-scale airfoils and wing taper from root to tip. Also a lot of them increase the size of the horizontal and vertical stab. Most "scale" kits for the mass market have a lot of deviations like this and for the average guy its just fine. Competition models have to be done to a higher standard and match the documentation that you present the judges. Again there are many deviations in three veiws from accepted sources. I have at least a dozen Spitfire three views and not one exactly matches the other but my airplane matches the one I chose to use.
So in answer to the origional question I think its matching the documentation as close as possible. Then comes sport or stand off scale that represents the subject closely. Then at the bottom is the kinda sorta looks like it ARFs. Some of the ARFs out there are really awfull looking but they sell a lot of them because a lot of people are more than happy with a plane the resembles something scale. Remember the majority of flyers don't have the building or flying skills required for an exact scale model. Don

my 2c,

After working in the aircraft industry for over 24 years, I believe that if the model is to be used in a scale competition, such as top gun, any deviation from the production documentation should be a deduction. There could be other events that allow for say a 10 or 20% deviation provided that the deviation is noted in the documentation.

Lew

Lew, The problem with that is most factory three views are so far off they are worthless. Factory blueprints have a drawing of the part and then all of the dimensions so the drawing doesn't have to be very accurate. As an example North American's factory three view of the Mustang is way off. Also how do you get production documentation when none exists as for WW1 or early airplanes? Also the judge has to go by the three view and pictures you modeled the plane from. If it matches that you get the maximum points.
Back to the origional question in the beginning of the thread, what do "you" consider scale. If the plane matches an accepted three view perfectly but the three view is 5% off is it scale? In my mind if it looks like the real thing its scale. If its a sport plane painted up to look like something scale its not. Don









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I'm all in agreement with Pittsdriver.

To me, scale means scale outlines, and a scale airfoil. Not too many full scale WW1 fighters had a Clark Y airfoil, and changing basic stuff like that puts it in the " Stand off in the next county" scale classification to me. Sure it 'll probably handle a lot better as a model, but it isn't scale.

Pittsdriver is correct. I have the ability to obtain scale information from actual aircraft that are in the museums. That was the type of information I was referring to. Additionally, I would have thought that the plastic versions of the models would have more accurate information, but obviously if they draw from only the 3 views that are incorrect, the problem still exists. You had brought up a point that I hadn't thought about.

Lew

In many aircraft with retracts you must vary the wing to house the retract
unit. While 3/8" bolts were good for real gear, .050 bolts would not do for a 1/8 scale plane. As far as WWII airfoils go we fly 100 to 120 MPH while are real airplanes were 400+ MPH.
Darryl Usher

Darryl, The speed of WWII aircraft is misunderstood out there. Lets take a Mustang. Sure it could do 400 at 30,000ft with everything to the firewall but for a short time because you'd be burning 120+gph. Take a fully loaded Mustang with a couple of full drop tanks and we are talking about 180-190mph cruise. At 55% cruise power a clean Mustang will do around 250. It does very nice aerobatics between 180 and 250 any faster and the ailerons get pretty heavy. So a 1/5 scale Mustang should fly in the 40 -65mph range to be scale. A 1/7 scale doing 100 is going way too fast for scale but you know who cares as it sure looks cool flashing past. Don

You can't do scale speed, a 1/5 scale J3 should go 15 MPH? Wing loading can't be scale eather. So the shape should fit the plans and the landing gear fit the wing and we will call it good.
Darryl Usher

Scale Flying...
I find this most aggitating! You take a 1/5th scale airplane to the Scale Master Qualifier. Your flying is judged by several different people who each have their own perception of what is scale to the real airplane. They ding you, because you are flying too fast, or that is what they perceive. Many scale models can not fly a true scale speed, due to high wing loadings. The problems overcome to keep a 100% scale airplane in the air are increased as the model becomes smaller. The aircraft reduces in size, but the air molecules don't. No one uses a redar gun or other device to know at what exact speed the model is flying at. Each judge has their own opinion at what speed something is moving through the air. It's like several different eye witnesses at a traffic accident giving their interpretation as to how fast the involved vehicles were moving. I build scale and fly for fun, but I don't get too hung up over the flying part, as long as the low fly bys are right down the runway!
"Keep 'Em Flying!"
Flak

I am not so particular as some as to what is scale but I do not like to see an engine head or muffler sticking out of a plane. This is one of the reasons I like electric planes. Scale planes look a lot like a full size and sport planes are toys that fly. I build both.

scale means exactly scale. If it of a bit than it is not quite scale.

Given simple error factors such as measuring device accuracy rounding errors in calulations, etc, etc, etc, you cannot ever conclusively achieve "exactly scale", that's why I voted for 1% off, although I believe that 2% is probably more realistic for the same reason as stated.