Knife edge wing
 

In the ama rule book...

6.6: Knife-edge wings are not allowed

So what is a knife edge wing?

Chris

RE: Knife edge wing
 

Poor description of prescribing a minimum LE radius? Isn't FAI's minimum LE radius 2mm or something?

RE: Knife edge wing
 

Yeah.. has to do with radius of the leading edge. It's not something related to knife-edge flight.

RE: Knife edge wing
 

That rule was changed by a proposal from Tony F in the last rule cycle (I voted against it as I thought it was too vague)

6.6: Knife-edge wings are not allowed. Leading edges must have two (2) millimeters minimum radius.

Change to:

6.6: Knife-edge wings are not allowed.

Intent:
In 34 years of competing in pattern I have never seen the minimum leading edge rule enforced. It is unnecessary for this to be in the rulebook.

The intent of this proposal is to simplify the rulebook and eliminate unnecessary wording.

Proposal passed 9-2

RE: Knife edge wing
 

But that rule without the wording is rather vague. If it's NEVER enforced, why not have proposed to remove it altogether, rather than generalize it to the point of not knowing what it meant without a history lesson? What was it hurting to have the extra wording in there? I've never seen it enforced either, and I'm not disputing it per-se, it just makes it more confusing. Knife-edge wing doesn't mean much to me.

Tony?

RE: Knife edge wing
 

Sort of like the weight rule. Hardly ever enforced, so let's get rid of it.

Draw out a 2mm radius leading edge. There probably wasn't a model out there that would have passed the rule if enforced. The Contest Board is a very funny committee to deal with. Probably if I had tried to eliminate the entire rule it wouldn't have passed. But keeping the wording "knife-edge wings" and just eliminating the measurement got it approved by a 9-2 vote. Really a stunning victory. Maybe next time someone can propose to eliminate it entirely.

Ryan maybe?

RE: Knife edge wing
 

I took a hole punch to a business card...7.5mm diameter and it matched my Prestige stab. The wing looked like about 10mm diameter (5mm radius) at the tip. So the Prestige would have passed (and probably the Bravo as well.) Happy to hear we are able amuse you! ;)

RE: Knife edge wing
 

I stand corrected. But I just checked a popular entry level model I have and at the wing tip it was smaller then 2mm. But what is the whole point? I have seen models with stall strips on them that certainly would not have passed if measured. It was a rule that long ago quit being relevant if it ever was. There are more rules like that in the book that should get the same boot.

With hindsight it could have been worded better. Maybe the CB could issue an explanation on what it means similar to the Masters Nats qualifying?

RE: Knife edge wing
 

Tony's got a point. Having installed stall strips on thick winged sport jobs before to make them do better stuff, their radius was around 2mm or just under.

The rule implies that a "knife edge" wing will hurt more than one with a larger radius when the wing hits you. Absurd.....! It is a silly rule

RE: Knife edge wing
 

Call me crazy, but I'm worried more about the prop and the spinner.[:@]

RE: Knife edge wing
 

Happy New Year Bob...

I actually completed the retrofit of Aesthesis with the Mintor 38 and took a flight today; only had enuff gas for one flight.

Unreal- Dec 31, north Joisey, 55F, no wind. Call ME crazy but that's about the best we've had in 10 years. Still remember last year same time frame....several extra days in hospital (knee replacement) due to the storm. A royal PITA getting back home

RE: Knife edge wing
 

Matt,

Happy New Year to you and all RCU friends and acquaintances!

Great to hear Aesthesis is up and running. I've been wanting to see that one flying for some time, but I know your Temptress is hard to beat.

Yes, a fantastic day for flying in our neck of the woods as well. I stayed at my small local field and flew the 62" Osiris and had a blast working on geometry for Advanced without the hindrance of wind. At least now I know what the figures SHOULD look like, lol!!

RE: Knife edge wing
 

5 or 6 years ago we had a warm spell here in early January, hit a little over 70 for a couple of days. Based on the latest data with us getting down into the mid 50's on Dec 31, I am about to start panicking that we're seeing the onset of Global Cooling. Or maybe it's just the Global warming induced Climate Change doing this. So confusing. Either way, I expect to see glaciers advancing through the area any day now.

Hey Matt, made a lot of progress on project X after we talked. Let's go flying tomorrow, before the glaciers hit! I feel the need to add my fair share of CO2 to start off the new year.

RE: Knife edge wing
 

I'm charging Aesthesis as we speak. Solberg?

RE: Knife edge wing
 

Well, technically we're not members anymore as of 1/1/12. How about Milford? Rt 209 is now OPEN!

RE: Knife edge wing
 

Better yet, let's go to Pocono for the 2012 Freeze Fly! There's hot food, as long as River Road is open.

RE: Knife edge wing
 

Milford sounds great.... We should try to go early. Windy in afternoon

Went to Jim's place yesterday and he filled me in on some intersting developments regarding he and Banshee. I'm sure he'll share. There was also a connection with the new movie "Red Tails", sequel to the Tuskegee Airmen. The man is living proof that one never knows who he may influence through flying toy airplanes well

RE: Knife edge wing
 

Jim is the reason I got interested in RC to begin with. He was at a contest at Mitchell Field back in the late '60s, doing his thing with the Banshee and I just knew right then and there that I wanted to do that too.</p>

RE: Knife edge wing
 

Tony:
We generally don't agree on this weight controversy stuff, but when it comes to the 2mm LE rule, it does seem to be outdated. Not that this rule causes many problems, but what is the point of carrying this forward as a safety rule when the AMA allows up to 55 lb. stuff to fly? This is probably an easy rule proposal to effect a change, just to remove clutter from the rule book.

RE: Knife edge wing
 

I am probably shooting myself in the foot here, but I know for a fact that most of out UMX airplanes have a LE radius of less than 2mm. I think the rule needs to be eliminated completely as it is no longer valid with the micro airplanes we have available to us.

RE: Knife edge wing
 

Iguess Iwould need to really check the rule book, but if this 2mm thing is across the board, then we had better stop flying foamies so that no one gets hurt!

Rule proposal time!

RE: Knife edge wing
 

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Yeah, and what about those indoor micro-film free-flight jobbers?
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Somebody could lose an eye!!!
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