Since I've been working on some new designs and 'researching' others, I've run into something that stumps me. I'm not sure of IMAC, Clover Creek or Tucson Shootout rules, but back in the TOC days all measurements had to be with-in 10% of scale. I've drawn up a few planes in CAD (outlines are as good as I get) and when I check the dims to some of the current offerings I've seen online and am not sure about mostly one measurement. All of the 3-views I have in my collection are measuring the fuselage length as tip of the rudder to the tip of the spinner. Now maybe some manufactures aren't specifying that their measurements are including a certain spinner, but back in the 'old days' the spinner didn't count because of different lengths available.

Example: Extra 300L

Scale length is 274" from tip of spinner to tip of rudder (ws is ~315")
Same measurement on a 40% is 109.6" (ws is 126", 40% scale)

Maximum fuselage length is 120.56", including the spinner.

Scale length measured from the front of the cowling (no spinner) to the tip of the rudder is 253.75"
Same measurement now on a 40% is 101.5"

Maximum fuselage length using the 'old 10% rule' is 111.65", not including the spinner.

I guess what I'm wondering is if there is a need to design planes with-in 10% of the full-scale for any competitions, or just make it 'look right'?

*OK, just found the IMAC rule book. So the planes are supposed to be with-in 10%... but does anyone ever check this? I know at the TOC and Masters you had to provide 3-views (before and during processing) to PROVE your plane was with-in 10% of scale. Haven't seen that since.

Thanks for the feedback,
Jason

I think they should make the 15% rule,, Seriously,

Don't Ask.... Don't Tell


lol

IMHO.. (Which doesn't count)... they should abandon the scale requirement.....

models are ahead of real aerobatic designs.... holding to some scale outline is holding us back......

grow a 2 meter pattern plane to 10 feet and make the flippers big enuff for 3d..... and THAT my friends will be the best flying plane on earth....

Originally Posted by Mithrandir

IMHO.. (Which doesn't count)... they should abandon the scale requirement.....

models are ahead of real aerobatic designs.... holding to some scale outline is holding us back......

grow a 2 meter pattern plane to 10 feet and make the flippers big enuff for 3d..... and THAT my friends will be the best flying plane on earth....

Sounds like my ShowTime 4D .90. Except it isn't 10 feet. lol

I know my feeling on the subject is unpopular, but the original concept was to have a event to miniturize full scale aerobatic competition, emphasis on the SCALE part. Hence the label "Scale R/C Aerobatics". Some (most) of the currently popular IMAC models are nothing but giant pattern "models" labeled Extra 300,330, 300L, Edge 540, etc. Some are so far off, the only way you can tell what they supposedly represent is by their graphics. Jason, the TOC manegment took the scale "thing" very serious because there was serious money involved. You can ask Hanno Pretner about that...
I guess what I'm saying is I think the scale aspect ought to be tightened, not loosened. If you want to fly pattern style airplanes, there is an event for that. It's R/C Aerobatics.
I also think the perfect venue to force the issue is the TAS. It,s rapidly evolving into the "new" TOC, and is starting to involve relatively big money. I also know that, like the TOC flyers of yore, the TAS flyers would meet ANY tightened requirement, and still water our eyes with their flying skills...
Old Dawg

Perfectly put there Old Dawg

I think we should have to fly with scale power to weight ratios! At least people would fly a smaller sequence. Just joking- that would suck.

Considering the work your going to put into this project if indeed it is to be the sizes you mentioned then I would bye pass public opinion and go directly to the judges. Or else you could find months of hard work and cost are wasted come the day you enter an event. I scratch build models of this size but I dont compete so for me, what looks right is all that matters. In your case, competing you cant afford to do the same.

Originally Posted by sweetpea

Perfectly put there Old Dawg

+1 as well Old Dawg

BURGER KING!

if yo design your plane within the 10% rule , your plane will never be disqualified . there are very few planes out there that are within the rules ..Better to be safe then sorry .. stay within the 10%

Originally Posted by JAS

Example: Extra 300L

Scale length is 274" from tip of spinner to tip of rudder (ws is ~315")
Same measurement on a 40% is 109.6" (ws is 126")

were good, we are 115" with spinner and 126" wingspan.

I think it depends on what you really want to fly. If you are purely a IMAC guy I think the extra length is fine, however if you are a 3d pilot I don't really think it matters and what looks good is more likely going to be the winner.

Just because the airplanes are flying doesn't mean they are legal. As it stands now, the rule is never enforced at local/regional contests.

Our airplanes come with no documentation. It would be nice if each airplane came with a 3-view that showed how each of the critical measurements has been stretched. You could just show that at a local contest. If you make it easy for a CD to enforce the rule, the rule will get enforced.

I like the look of a scale airplane. Sometimes that has more to do with fuse shape and other things than it does length.

"SCALE" is sooooo 20th century....

IMHO, we should be doing all out awesome flying planes and to H3LL with scale....

c'mon... we are in the 21st century... lets build models the full size guys try to copy!!!

lol