js3

My Feedback: (3)

Where is the burden of proof? Prove to me that the cross section is diamond shaped with 1/4" radius and not a square cross section with a 1/4" radius. After all, a diamond cross sectioned piece is just a square rotated 45 deg.

As to your point of a rectangle including straight sections, like I said above, I would just run a sanding block down the length of the "tube" every 90 deg. Then the straight sections could be as little as .001 or even .0001 of an inch. Or even less for that matter.

Your point about the wing being constant chord however is interesting. I'll have to think about that one.

HighPlains

My Feedback: (1)

Of course the wing is still constant chord. Otherwise any plane with fairings that extends onto the top of the wing would be considered to have non-constant chord, because you cann't see the part of the wing under the fairing.

garys

Are you sure? I believe you are referring to are part of the "fuselage" that blends in the top of the fuse to the top of the wing at the leading edge, correct? I don't disagree with that point at all. Just like a mid-wing Q500 is 100% legal, even though the center section of the wing is completely hidden by the fuselage.

What John was saying is that in the case of Albert's design, the "booms" are considered part of the "wing", not the "fuselage". If the booms are considered part of the wing (which I personally don't believe), would it still be contant chord? I would think not, as the chord would be considerably longer where the booms are than the rest of the wing.

And yes John, the rules don't say how straight the sides are on a rectangular cross section. I would tend to interpret it that there has to be a visible straight section, however. The rules don't say who the burden of proof is up to, so it's going to be a CD's call. If I were the CD, I'd want to see the straight sides, top, and bottom, and if they weren't visible (because they were so small), I wouldn't allow it. If the pilot wanted to challenge me regarding proof, I'd challenge him to show me where the rules say the burden of proof is on me rather than him. That's one issue of the AMA rules compaired to the FAI rules. For example, the FAI rules state the burden of proof is on the pilot to prove their airplane meets the minimum cross section area rule, including being able to show a cross section drawing.

HighPlains

My Feedback: (1)

Here is a 1/2" square fuselage with 1/4" radius on all corners.

http://www.graphitestore.com/itemDet...d=34&curPage=1

garys

Show me the flat sides that define the "square" cross section? That tube has a circular cross section, not a square section with rounded corners.

HighPlains

My Feedback: (1)

It meets all the criteria of the rules which spec 1/4" maximum radius. I admit that this is taken to the limit, but find nothing in the rules that void it. There is no rule that spec's a flat surface. Even defining what flat is would be difficult, since I doubt that you could find a truly flat glass fuselage or even wood that has been glassed.

garys

Show me that tube when it was a square, before it was reshaped into a circular cross section.

That tube meets one aspect of the rules which require a rectangular cross section with up to a .25" radius on the corners. It's still not meeting the rectangular cross section based on the definition of a rectangle.

I'd say there has to be some attempt to produce the rectangular cross section or I wouldn't allow it if I were the CD. The rules that you helped write are ambiguous in that regard, and since the burden of proof isn't specified, if I were the CD I'd say it's up to the pilot to prove to me it's legal. You're a smart person, so find me a geometry textbook or something that says a perfect circle that started as a square is still called a square, and I'll change my mind. But then the burden of proof is on you to show me that a 1/2" diameter fuse was truely a square you started with, and not a diamond... I guess you'd be showing me the fuse with the 1/2" square boom, before it was then reshaped into a tube?

And I just checked one of my NemeQ+'s with a steel straigedge. Since the plugs for the fuse were machined, they are flat on all four sides with the radius on the corners, except for the last 2" of the bottom where the fuse blends into the tailskid on the bottom. Even where it's less than 1/2" wide accross on the top, there is an obvious flat area.

[email protected]

Gary, you make a very good devils advocate...............and you know it! Don't I owe you a sunhat from past w/c we have met at? Everyone has assumed that the radius is taken to maximum allowed, is this always the case. I also play devils advocate. I cannot find anywhere in your rules ( at a quick glimpse) as to what defines a straight line- is it 2 thou, is it 100 thou.
The onus, in my mind, is always on the competitor to prove compliance and if he tells the CD that this is his personal interpretation of the rules I doubt whether, short of a Contest Jury being available ,that he should be turned away.
I don't really know your rules so my comments could be out of order so please accept my apologies if I am in error. regards trevor h[[8D]]nz

js3

My Feedback: (3)

Gary,

Your Neme-Q didn't come out of the mold with square corners that were then rounded to a 1/4" radius. No, it was molded that way with the radius already built in. Thus, the 1/2" CF tube is molded with the 1/4" radius already "built in" the same way as the Neme-Q, Vortex, Shotgun or any other molded fuse. There is no requirement that the fuselage start as a true rectangle in cross section that then is allowed to have a 1/4" radius added on all sides. If there were such a rule, then all molded fuselages (at least ones with the corner radius molded in) would be illegal.

garys

True, the NemeQ, or any other molded Q500 didn't come out of the mold with square corners.

But...the NemeQ does come out of the mold with obviously flat sides that can show that there's a rectangular cross section with the corners rounded off. The tube has no flat sides to show that there's any resemblence to a rectangle.

It's easy to get me to change my opionion. Since a square is a form of a rectangle, just show me where a circle is defined as a squre with it's corners rounded off, and that it is then still called a square.

luv to race

My Feedback: (1)

The radius on the Vortex's are all sanded to shape.. They start as square as the fuse is wood.

Good thread though, interesting reading. I kind of like the P-38 looking quickee. I also like the "runt", especially the take off. I'd like to fly both of those.

RB

garys

Trevor, hopefully I'll be able to get a hat from you in Germany next year Yes, I love playing devil's advocate The underwriter's at work love me for it, haha.

The rules don't list a minimum dimension for the flat sides, prior to the radius, however, they do say they must be "rectangular" in cross section, but they can have rounded corners. Once all straight sides are removed due to the radius, in my opinion it's no longer a rounded rectangle, but a circle. I've said several times that if somebody shows me where a circle can still be considered a square, that I would change my opinion.

The rules also do not state they have to start as a perfect rectangle and then can be rounded, so molding them that way is perfectly acceptable.

RB..I agree, they're pretty cool looking airplanes. I'd like to see if the "runt" took off as bad as Dible made it look

daven

My Feedback: (1)

Gary,

I agree with your interpretation, mine is the same. Now, if you could find an oval shaped carbon tube with at least some semblence of a rectangle with 1/4" radius' I would buy that, but a circle, no.

I flew a plane similar to the runt, and the takeoffs were exciting, even with a 3" tail skid to keep the angle of attack not too steep. It was manageable with an OS, but very uncontrollable with a nelson.

HighPlains

My Feedback: (1)

If you can stomach pushing about 1/2 down elevator on the takeoffs, the shorties do OK. The real secret was lifting the tail into the air so the wing didn't start off stalled. The worst takeoff the airplane went out about 10 feet and did a 180, then it flew around two guys starting their engine (all during a test flight) in another 180 at about waist height. Finally a touch of rudder got it going in the right direction. There had been about 15 guys standing around the start line waiting to test fly. Runway wasn't so crowded for the next test flight.

I rather like the out of box thinking behind the Hauler. It may not offer any improvement over a full fuselage design, but for the first time, a ^-tail was put on the right side up. Two possible problem areas: it might be a be-itch to launch, both from what do you hold on to and the tail grabbing you. Second, unless the fuselage "pod" is shaped very carefully, the drag might be pretty bad. But everyone knows that a standard fuselage is much much longer than the 3.3:1 length to width ratio that gives the lowest drag.

Are the booms part of the fuselage or not? I don't know. If they are, then the maximum radius requirement tend to dominate the shape as any structure is shrunk to 1/2", and thats by the rules. All I can say is that carbon tubes of that size are pretty strong, but still have some flexibility.

All that extra weight that quickies have to haul around gives rise to some interesting posibilities in design.

[email protected]

gary, will have a hat for you in Germany- my wife has indicated we shall be there as long as I paint the house.............if not I'll get a hat to tyou somehow by legitimate means, trevor H

vicman

My Feedback: (10)

Draw a 1/2" square, find the center and draw 1/4" radii for all 4 corners and see what you have

garys

A "circle", NOT a "square" or "rectangle"

vicman

My Feedback: (10)

But they can be both especially with the current definition of how things work.
From a manufacturing standpoint you can bore a 2" ID in 1.5 OD bar. Just won't be much of the original bar left.
Personally I think the design shows a great amount of creativity and hope it works well.

Ed Smith

You guys need a dictionary.

Rectangle:-

Quote "A plane figure with four straight sides and four right angles, especially one with unequal adjacent sides."

Square;-

Quote "A plane figure with four equal striaght sides and four right angles.

Hole:-

Quote "An empty space in a solid body or surface"

Not so, there would not be a solid body left, therefore no hole.

Ed S

Clark L

I can't believe this discussion is still going (yes I can)....

3) Cross-section: The fuselage shall have a simple, rectangular “box” cross-section with a maximum radius of 1/4 inch at the corners.

I dont know, that reads pretty clearly to me... Justify using a round tube all you want but if it doesnt have a rectangular cross-section, it doesn't appear to meet the requirements (or intent) of the rule.

Of course, personally, I dont think those tubes should be considered "fuselage" anyway... They look like empennage booms to me

djlyon

empennage - The stabilizing assembly at the back of an airplane. I don't believe that there is any requirement that it's attachment to the rest of the airplane be via the fuselage, although that is kind of a convenient way of doing it.
This is so fun

Denis

js3

My Feedback: (3)

Clark L,

Don't start with the business of the INTENT of the rules. Q500 now is a VERY different animal than it was intended to be. Don't Go there.

Randy B,

I stand corrected on the construction technique of the Vortex. I apologize if I've misled anyone.

Gary,

I still am not conceding the fact that the tail booms would be considered fuselages--they're not as the fuselage would be the "pod" section which is connected to the motor and wing.

However, for the sake of argument , you seem to be saying that a 1/2" diameter tube would be acceptable if it started as a 1/2" square.

How about this:

My "fuselage" or tail boom will be constructed of pieces of bass wood that I found in the doll house making section of my LHS. These pieces are a bit like triangle stock in cross section i.e. the cross section is a right triangle with two edges measuring 1/4" per side oriented 90 degrees to one another. However the third side of the triangle, rather than being a straight line oriented at 45 degrees to the other sides is concave with, you guessed it, a 1/4" radius. I'll use four of these pieces to construct my tail boom such that each piece is oriented 90 degrees to the adjacent pieces and so that the concave portion of the stock is toward the inside of the boom. Now, in order to attach these four pieces of bass wood, I'll need to use a building jig or crutch. Conveniently enough, the perfect building crutch just so happens to be a 1/2" diameter CF (or whatever material) tube. Now that I've attached the wood to the tube in the manner described above, I have a boom (or fuselage if you insist) that is 1/2" square. So now, because the rules allow the fuselage to have a 1/4" radius between the sides, I'll sand away enough of the bass wood to leave 1/4" radii on four sides.

So I am left with a 1/2" square fuselage with 1/4" radii on the four corners.

Clark L

Maybe this will help...

diggs_74

I don't know about this new version of the Hauler but it should say something when the only guys discussing it are the ones whom haven't flown it.. We have a couple Hauler only heats once and a while and if there's more than 2 that make it into the air it's a miracle..

On the other hand, I believe this will be the most successful version to date.. I don't think the first ones had enough tail area myself..

js3

My Feedback: (3)

I too applaud Albert's outside-the-box thinking. All too many people believe that the way the rules are written state that a Q500 racer must look like a Vortex.