RE: Plastic Props
 

Judging by the number of threads on the Quickie list for the past 90 days { 78} - vs. the 7 threads Q40 over the same period, one might think that Q40 is already a dying event. Is it do to higher speeds? I doubt it, since the top speeds are only slightly higher than 428 Quickie. Higher costs? One molded airplane costs about the same as another, engine about the same. Higher difficulty in flying? I think that Q40 are easier to fly than Quickie, though you might make the case that the landings are slightly more difficult. So what is left that presents a barrier to greater numbers of racers and more races? I only see the prop, and I would guess that most would agree.

At the last rules rewrite, I suggested and pushed for changing the fuselage height requirement to the rest of the committee. My reason was that at that time only Mustangs and Mustang derivatives were being built, since they were not exactly following the intent of the rules in terms of cross section with their “speed bump” belly pod radiators. The result was predictable, planes like the Polecat and other Goodyear/Formula One designs were now going to be competitive. I doubt that this change made the designers and sellers of those designs happy, but I believed that for the growth of the event it was necessary.

As far as predicting the future, as an engineer by training, yes I can predict the effects of rule changes. With the engines at a rather stable level of development, we have a fixed, limited amount of horsepower. With the airframe rules static, we have roughly stabilized the airframe drag. Since the propellers have been developed to a rather high level by some of the competitors, then not expecting a radical increase in speeds with composite props is reasonable and predictable.

Letting an event die because changes might not be exactly in your favor seems rather petty. Racing has been on the decline for a long time. We have out-priced, and out-tech’ed too many potential RC fliers from racing. Tony Pacini is correct about what it takes to have contests. Most clubs view racing at their field as a fund raising activity, and that takes entries. When they don’t make the money, they stop having races.

I proposed a Sport Formula One event in the last rule cycle. It would have been Formula One designs scaled up for .91 engines and only flown at about 130 mph. True, 424 Quickie is about this speed, but a lot of people seem to think that the model airplanes they fly should look like an airplane and not the box it came in. The proposal received a 6 for - 5 against final vote, so it failed to pass. It’s purpose was to get scale racing into the ranks of the average RC’er at the average field. Once you get a course on a field, then it is easier to bring in the faster events. This is because it would have allowed more people to buy into racing, even though they might not be flying the fast events. But several on the contest board seem to think that allowing other events will dilute Quickie and Q40. Perhaps they are right. But I am constantly surprised at the number of local warbird, trainer, one-design events that keep popping up at clubs across the country. Yet none of these types of events appears to help add to the ranks of pylon racers in Quickie or Q40. Why? Because they are outside the AMA rulebook events, so they have no national following. I intend on submitting the same proposal with some additional simplification the next rule cycle. Perhaps by then 422 will be just a memory as the original Formula One is today.

RE: Plastic Props
 

Bob,

I agreed with the lower fuse-height for non-mustange type airplanes, but I disagree with your thoughts about props, so you think I'm petty, I can live with it.

I just looked at the last 10 threads listed on the Q500 forum. Of the last 10 threads, 4 were about Q500 specifically, 3 about Q40, and 3 were just general racing questions or other classes, or not really about racing at all. Just because a discussion isn't in the Q40 forum, doesn't mean Q40 is not being discussed. I'm sure if you go through all the threads from the last 90 days, you would find similar results, although I would naturally expect more discussions for Q500 due to there being more divisions of it (424, 428, local deviations) compared to Q40 (422 only).

"As far as predicting the future, as an engineer by training, yes I can predict the effects of rule changes"

I hope your engineering backgroud is better at predicting the future than it is as giving out accurate data. I really don't see how you can guarantee the carbon props are at their developmental limits, as the current prop wasn't even developed to take advantage of it's material and manufacturing properties.

I really don't see why simply trimming the current prop wouldn't be a good solution....

GS

RE: Plastic Props
 

Gary,

Nothing is personal here, just a good open debate, right? I said that if we let an event die, when we could make a few changes that would promote it would be petty, not saying that you are petty for opposition to the ideas. Trimming the prop might work, though one guys trimming might be the next guys reworking. What ever happen to heat guns anyway?

I have always shared my discoveries in racing to try to promote the sport. This is not always the case with some. For instance, when Jim Walker invented the bellcrank and started the U-Control in the 40’s, the first thing he did was obtain a patent and I believe that he collected something like 50 cents for every kit that was built for years. So when I came up with the high aspect ratio wing in pylon in ’87, I could have easily got a design patent on the concept and made a bit of money or froze out the competition for quite a while. Same thing for the idea of the increasing width fuselage in Quickie where the widest point is at the trailing edge for drag reduction.. Instead, I published the concept in an article in Model Aviation in ’98. Same thing for fuel tanks on the CG.

Do you know why the new rules specified wood props needed to have two blades of equal area, length, and shape? I had discovered that I could run a prop that was about a blade and a half and pick up about 4 seconds on a Formula One. Unfortunately, I had shared that little nugget with Duane Gull and he didn’t forget about it at that last rewrite. Because of the time working with Chris Machin at Rev-up, I flew a experimental laminated wood phenolic impregnated prop in Phoenix that was about 50% stiffer than regular maple. That allowed a much thinner blade, good for about a thousand rpm. I was the only guy in the country that had access to that prop, but I only used it at one race. You will notice that the rules kind of ban that type of propeller now too with the language of “a single piece of wood”. The minimum length of airplanes made it into the rules perhaps because I was flying quickies shorter than people thought possible. They were quite a bit faster. I told Phil Buscell in Dallas years ago (1980) that I was going to build a diamond shaped quickie because it would meet the width and height rules and give the effect of wing fillets with a much smaller fuselage size. Got the idea from an old Lou Andrews control line design from the 40’s Banned the very next rule cycle. Good thing too, would have been a bit ch to build.

So what I am saying is that sometimes we need to give on some cherished ideas or advantages to promote the sport. Wood props in Q40 is one of those areas. And that’s very hard for someone that would rather fly a wood prop in most cases.

Oh, and BTW, my numbers on the threads were accurate. I didn’t say what the threads were about. (A little spin doctoring in this election year seems appropriate.)

Bob Dible

RE: Plastic Props
 

I love a good discussion (debate?) and this is one of the better ones.

I don't think that Q-40 is "on the ropes" or on the verge of dying. It is the fastest event, the most expensive, requires more skill (perhaps), and can't be flown easily at shorter fields. It is the crown jewel of the racing community and, as such, isn't destined to be the most popular. Q-500 is simpler in many aspects which helps explain why it's more popular than Q-40.

If I could carve fast wood props AND if I felt it gave me an advantage (which it might) I suppose I would have a different perspective. That's not the case, though, and I believe the same applies to the rest of us. Those who can carve are in the minority. That doesn't make them wrong, just outnumbered.

Making the event a bit easier won't take anything away from the experts. It may narrow the gap a bit but the winners will still win and the duffers (like me) probably never will. The cream always rises to the top and this case is no exception.

That plastic prop had better work EVERYWHERE (on a healthy engine, anyway) or it really doesn't make things much better. Making the event easier might draw more pilots into the event. Allowing a series of plastic props which WOULD work everywhere should be a step in that direction.
Last time I checked racing numbers were down in most areas. Growing the event shouldn't hurt. Remember that much of the current racing crowd has been around for a while (and won't be around forever) and we must draw new pilots in order to keep this event alive. This current generation (myself included) will be less enthused about carving a prop to be competitive than the seasoned modelers are. Think about the younger newcomers - they are the future of this event.

I'm sure that Fred is capable of producing a faster molded prop. His is just a copy of a hand-carved wood prop and was intended for practice only. If he started with a fresh sheet of paper I know he could do better.

I'm certainly not in favor of putting wood props at a disadvantage. IF the current complaint is that the current plastic prop is too heavy for use in all areas then the logical solution would be to design, test, and allow LIGHTER VERSIONS that COULD be used in all areas. Since you don't go faster by using less pitch (with a given diameter) I don't see how speed creep would be an issue in this case. I'm not saying that we should allow an infinite number of different molded props which WOULD turn out to be faster.

Making the event easier for most WON'T tip over the card table and make everything even for everyone. It should make the event easier for most to approach, though, and therefore it should increase participation. You winners will still win. Increasing the number of participants will guarantee that there's still an event for you to win in the future.

The props aren't an issue for me. The one that's allowed works fine on my stuff and when it won't turn up anymore it's time for an engine rebuild. I spend more on gas driving the 90 miles to the field and back that it would cost for a wood prop. If for some reason I couldn't use the plastic ones anymore I'd have to learn how to carve or just drop a few more bucks. Either way I'd still race. I'm already hooked so you don't have to worry about losing me (and I'm sure you aren't). My concern regards the added difficulty of NOT having readily available, competitive props for everyone.

The average newcomer won't know where to buy a competitive wood prop let alone how to make one. He or she is also likely to tear up a few in practice, too. They must be readily available or it's a deal breaker.

Formula One died because it was just too "everything": too loud, too expensive, and too hard to figure out. A plug-per-run on a good needle, an engine-per-run on a bad one. F1 pilots didn't go away they just started flying Q-40 instead (probably just 'cause it's easier). Most (if not all) those getting defensive about the wood props cut their teeth in F1. You won't have this argument with someone who started in Q-500 and has never carved a prop before.

You've all made good points and I'm sure that nobody meant anything personal. Dan's one of the nicest guys I've ever met and I can't say that he's shown even the slightest hint of an elitist attitude. I don't believe that comment was directed at him, anyway. Don't take it personally, Dan. Bob's general line of thinking about allowing plastic props that could work everywhere might not be such a bad thing.

RE: Plastic Props
 

Bob,
Yes, nothing personal. I already said to define a set amount of each tip that can be trimmed, thinned, reworked, etc. If somebody goes beyond that (farther in from the original tip), they're disqualified. I haven't heard of people using heat guns in a while, but I'm willing to bet there's going to be some engine and prop inspections done at Phoenix during at least one of the races in the winter.

I guess I just don't get the true reasoning for allowing more carbon props. The APC prop was allowed because it would give the less experienced the ability to bolt on a prop and be competitive, and it works great at that. The way I look at it, modified wood props is the ONLY tangible item that makes Q40 more difficult than 428 Q500. The engines aren't any more difficult, the airplanes aren't more difficult (or more expensive), the speeds aren't different enough to be more difficult. The art/black magic/etc of making a good wood prop is different. If we take out the one thing the realistically makes Q40 different from 428, why bother having both events?

Oh, and Bob...regarding the numbers of the different threads....what political office are you running for?

GS

RE: Plastic Props
 

Gary,

Only one that I'm qualified for - Dogcatcher !

RE: Plastic Props
 

I forgot to add that I am Bob Dible and I approve of this ad.

Only one that I'm qualified for - Dogcatcher !

RE: Plastic Props
 

Gary-

This thread started with a wish for LIGHTER props which shouldn't be a threat to the good woodies. I don't believe anyone in this thread has proposed anything that might put good wood at a disadvantage.

I agree with your point that this little "fiddle factor" is the biggest difference between Q-40 and Q-500 and that it should probably stay. It's not the ONLY difference, though, just a distinquishing one. Q-500s are easier to build, cheaper to buy (even in molded form), and land more like a lightly-loaded sport plane. Like you said, though, take away the wood props and it's nothing more than a glorified Q-500 event (not necessarily a good thing).

RE: Plastic Props
 

Bob, I question your qualification for being a dogcatcher...what makes you qualified as such?

Tony, The biggest issue I have is just how is a "lighter" prop going to come about? How can we be assured that it won't be faster? I really doubt it would just be the same exact prop but with less pitch, and like I said before, I wouldn't blame Fred for making it faster if he's allowed. I think the easiest way to make them "lighter" is to allow a certain amount of the tip to be trimmed, thinned, or whatever.....no other airfoil changes, pitch changes, just reworking of the tips. Seems to be that it would be the easiest way to give people what they claim to want (more RPM's for poor weather conditions). The problem is realistically, if a new prop is allowed and it's faster at all, it would put wood props at a disadvantage, and that "tinker factor" would be gone. In most cases, the current carbon prop is better than all but the absolute best wood props, and I've been to several races where the only props that were really going fast were the carbon ones.

I seriously doubt adding a bigger selection of carbon props will entice any more people to try Q40 than if we simply allowed people to trim the last .25" of each tip to gain RPM's. Maybe I'm wrong, I've been wrong before, and will be wrong again......I just don't think I'm wrong this time.

GS

RE: Plastic Props
 

Gary,

Back when the black prop was being introduced for competition and our rules changed to allow it, I proposed that it should be legal to clip the tips up to 1/4" so that the prop could be used in a wider range of climates. That went over like a lead balloon. I still think it was a good idea then and it is now as well.

You make valid points and perhaps you have hit upon a good compromise: Allow the tips to be modified so as to make the props more usable while keeping the wood carvers happy by not introducing new equipment.

BTW, I still have to laugh at the whole 8 vs 8.0 fiasco! :)

RE: Plastic Props
 

Yes, I concede that the tip-trimming proposal is the quickest and easiest fix and nearly guarantees that the plastic props won't be any faster. The heat gun would still work, though, and the trimming versus re-work issue would rear it's ugly head. Nobody's really policing the props at this point (not even checking to make sure they're 8.0s and not 8s). There would always be allegations that the guy going fast is using a "hot" (massaged) prop. Might be tough to check......

Great idea, though. You've evidently put a lot of thought into this. Has anyone tried trimming .250 per tip and measuring the RPM gain? That tired old engine on the front of Tanner's Polecat (that wouldn't pipe up at the Basin) might just have some life left in it!

RE: Plastic Props
 

Tony,

Perhaps you can trim some off a prop and see how Tanner's engine likes it. I had never thought of simply trimming the tip, it was mentioned by Terry early in this thread, and I totally agree with his thinking. I don't think there would be any more "trimming vs. rework" issues as there currently are now. I know many people's "flashing removal" seems to increase their RPM's, but I've never seen a change....maybe I am still leaving too much flashing? I think if the rule was such that only the last .25" of each tip (measured from the original tip) was all that could be touched, it would be fairly easy to police (6.9" of the prop diameter still must be 100% stock).

Funny that you mentioned props not even being checked at most races. Jim Allen and myself talked about that subject, as well as engines, about a month ago. Don't be surprised if there are checks at the next big races in Phoenix.....

John,

I was one that was against the .25" allowed when the carbon prop was introduced, and I don't think it would be much of an issue if the 7.4x8 prop was still in use. The last time I ran the 7.4x8 at a race, I switched to wood because the engine was spinning over 25k with the carbon. I know Fred had to recut the mold, and don't know if the change was intentional or not, but it did change. By the way, all his molds need recut periodically to keep the parting lines clean, and he goes through several molds for the popular sport props every year.

GS

RE: Plastic Props
 

Trimming the tips works very well. Just a 1/16" off each tip really helps get the rpms into the 23K range even on a bad day. I have a bunch of CF props where just a small portion of the tip is bent over from props not stopping at TDC. One of my engines stops at all kinds of weird spots and it not very consistent. If you nose these over on tar, scratch 1 prop.

They did do pretty good spot checks at the Nats this year. Not only for weight, but venturi size, and a gauge to measure the CF props for length and proper size. I think they found one of the carbs in the 11mm range. They checked alot of the fast guys, and even my engine.

I'd be all in favor of allowing the last 1/4" of each tip modified of the existing legal prop. Now how do we get this through without waiting until 2007?

RE: Plastic Props
 

Allowing 1/4 of an inch to be clipped with no further rework down the blade is a bad idea for a rule change. Rules have to be enforceable this suggestion is not. If just a 1/4 inch is chopped then no further tip blending would be allowed as this would extend the rework down the blade more than a 1/4". How would anybody measure this?

Instead of dreaming up more silly unenforceable rules why do we not enforce or correct what we already have. READ THE RULE BOOK and do not just use the parts that suit you best.

The cowlings on the latest crop of Q40s are illegal.

The Nelson muffler is illegal.

Vee tails for use as a stab are illegal.

Fibreglass Landing gears on Q500s are illegal.

Racehorse Starts are illegal.

All of the above mentioned rules are continually ignored. Now you want to enforce a 1/4" of the prop rule. Good Luck!!

Ed S

RE: Plastic Props
 

Ed

What are you talking about? It would appear that you haven’t read the rules lately!

“Instead of dreaming up more silly unenforceable rules why do we not enforce or correct what we already have. READ THE RULE BOOK and do not just use the parts that suit you best. “

Here are where you find the sections that cover your concerns.-------------------

The cowlings on the latest crop of Q40s are illegal. – Section 16.1.1.C.4.c allows for a cover to restore contours of the fuselage

The Nelson muffler is illegal. - Section 16.1.2.a.4.a,b,c deals with tuned mufflers

Vee tails for use as a stab are illegal. - Section 7.3.1 mentions the use of V-tails for control

Fibreglass Landing gears on Q500s are illegal. – What? Are they too thick?

Racehorse Starts are illegal. – Everything is Addendum A are not rules, but suggestions

“All of the above mentioned rules are continually ignored.”

Again the Canadians just don’t understand their big brothers to the south

RE: Plastic Props
 

Oh dear, Oh dear, Here we go again. Another hostile tone.
For the past two years I have been one of the starters at the US Nats. This year I was an assistant starter as well as the starter for F.A.I. F3D and F5D. Do you really think I would stand out there running the event without knowing the rules?.

Yet again there are some Americans that just do not understand their Brothers to the north!


I will let the rules speak for themselves.

Rule 16. 1. 4. (c) the very first sentence says "Removable cowls prohibited".

Rule 16. 1. 2. (c) the last part of the last sentence, "...and both the inside and outside diameterof the outside shell shall remain constant for at least 4 1/2 inches". I trust you can measure?

Rule 7.1. Conventional design.
Aircraft used in RC pylon events shall be of conventional design with forward wing, aft horizontal stabilizer and a single engine mounted in front.

your Vee tail is acceptable for yaw control only!

Rule 16.2. 1.d The fourth sentence. "Struts shall be either round wire, at least 1/8 inch in diameter, or Flat Stock no more than
1/8 thick". molded gears hardly fit the description of 'Flat stock"

Under "Operation of the race", not some imaginary addendum read :-
Rule 13. 1. 9. Third sentence:- "The aircraft shall be flagged off the starting line in two groups, The first group in lanes #1 and #3 and the second group in lanes #2 and #4.

So, to use your hostile tone, it would seem that my "Brothers" to the south simply cannot read, Or if they can read they cannot comprehend what they read.


Now we can have hostile verbal battles if you like. I can more than hold my own in that arena, or we could do as I suggested in my post. Enforce the rules or correct them. I do not have access to the AMA rules making process. If as you say you do then rather than wasting your time sparring with me, spend the same amount of time working to correct the ambiguity in some of the rules.

Ed S

P.S. I lost count of the number of models at the NATS that did not carry numbers. Read the rule on that one!

RE: Plastic Props
 

Ed,

I don't doubt that you are holding your own.

The portions of my post that appeared "hostle" were quotes lifted from your post.

No doubt there are conficting sections of the rules.

What shape are these fiberglass landing gear? We allow the shaping of metal to an semi-airfoil, so what?

I guess I will have to look closer at the Nelson pipe, but the INTENT of the rules allows them, perhaps a measurement error occured.

I don't doubt that many airplanes did not carry proper registration numbers. It's been a problem for decades. That should have been corrected at registration, not at the starting line.

Your BIg Brother

RE: Plastic Props
 

Ed,
Allowing only the last 1/4" of a prop to be reworked is enforceable. Like Dave said, a 1/16 inch off the tips can make a big difference, and that would allow 3/16 to blend to the rest of the prop. If somebody were to take 1/4" off a tip, they simply couldn't blend in a nice tip shape, it would just be cut off square. Before anybody says that's not enough to blend to a smooth tip, most of my wood props basically only have the last 1/8-3/16" of each tip shaped.....

I'll let you argue with Bob regarding your other rules issues. I agree with you on some, but not all of them.....

GS

RE: Plastic Props
 

Gary,

I'll hold the Northern border if you get the Southern.

Hounded

RE: Plastic Props
 

Ed,

Don't blast me on this, but I thought there was something in the rules (don't have a book handy) that mentioned you could have "either" your AMA numbers on the plane, "or" your name and address located somewhere on the plane.

Maybe it was a dream, but I'm not sure.

The problems with many of the rules, is that they contradict each others in different ways through out the book.

How about firewall size? Must be 2 1/4", but is this measured at the front of the firewall or the back? After looking at the rules, its not very clear. I would agree the intent would be at the front, but going by the way it is worded that is not the case.

I'm thinking about a 3/4" thick firewall so that I can skinny up the nose at the front. May have to use one of the older motor mounts, but thats ok.

RE: Plastic Props
 

That's a good one Dave,

I believe that everyone has always used a projected line for the 2 1/4" because of the 1/4" radius is allowed in the airframe on all sides. Since so many are now using radiused mounts, both methods are allowed. But I guess you could say that the front is 1 3/4 flat section with 1/4" radius to the fuselage sides.

BTW, you can access the AMA web site to review the rules in a PDF format.

Ed's right on most of his points, the rules are a lot like Human DNA. A lot of verbage survives that no one really has analyzed. And this was after a clean up. We need to strike horizontal from the "aft tail".

I don't know how the error on muffler tube length came in. Maybe someone was measuring one from 10 years ago...???

RE: Plastic Props
 

Well,

I just checked the rules, and I didn't see the portion about name and address inside the plane that I am sure I remember from someplace. This should be caught in pre-inspection, all you would have to do is write your AMA number (in 1" tall numbers) on your lane Sticker as I saw quite a few people do.

As to the race horse start, the rules do state that 1 and 3 go first, and 2 and 4 go second. However, it also states "unless otherwise specified". Not sure if mentioning it before the finals counts as "unless otherise specified", but I prefer the race horse start anyways (especially if in an even lane).

What about the "go when ready rule". Its in the book, if agreed upon at the pilots meeting. Why don't we use that rule?

RE: Plastic Props
 

Again, Read the Rule. It quite clearly states "The front firewall" shall be 2 1/4 square. That is the wall that the engine is screwed to.


We do use the rule. However if one pilot disagrees then it is not agreed upon and cannot be used. Furthermore, anybody who advocates to "Go when ready" totaly does not understand the importance of establishing their own one minute starting procedure.

Ed S

RE: Plastic Props
 

Yep, it does say "front" firewall. Must have missed that.

I'm not sure about how you are intepretting the go when ready rule. I don't see anything in there about having a vote? Can't the CD make this call?

RE: Plastic Props
 

Hi Dave,

In your very first post on this thread you said something about a can of worms, wasn't that the truth!

Rule 13.1.8.2.
If determined at the pilots meeting before the race, the heat may be started on a "Go when ready" basis, that is when all Pilots and callers are ready before the starting period has elapsed. If the pilots have elected to go when ready, the starter shall...............

The underlined section would indicate a vote would it not? Yes the CD can make the call as well.

That is it. I am not explaining any more AMA rules to AMA members!!!!

Ed (The Northern Brother) S