Nats Clover-Please help

LAST EDITED ON Jun-30-03 AT 12:43 PM (CDT)
 
I just finished re-reading Keith Trostle's wonderful Stunt News 4 leaf clover article. I felt this was a good idea since I spent the whole weekend arguing with my flying partners what a clover looks like. Keith did a wonderful job of explaining the "misconceptions" (my word) about the clover and how it should be judged.

I say "basically" it is the size of two vertical eights side-by-side. The rules say the tangents of the 4 equal circles must touch 5' and 90 degrees and each other. To do that, your starting point must be somewhere around 45 degrees!!!

Of course, I was told that clover will not score the big points. The "big point" clover starts at about 35 degrees, has top at about 70 degrees, has 4 little bitty loops, and is flown in a space about 50% wider than the vertical eight.

I can fly and coach it either way, so I will definately fly it however the judges want.

Could someone please tell me how the clover is to be judged?
"Per the rulebook" answers are not requested.

Signed,
Frustrated in Big D

LAST EDITED ON Jun-30-03 AT 12:50 PM (CDT)
 
>Could someone please tell me how the clover is to be judged?
>"Per the rulebook" answers are not requested.

Sorry, that's the only possible answer. Keith's change (start at 42 deg) is not approved or implemented yet. I would suggest you fly them as we have in the past, and from there on, it's up to the judge.

This would be an appropriate topic for the pilot's meeting.

> This would be an appropriate topic for the pilot's
>meeting.
>
> Brett

Crap. I was going to go practice chipping.

Thanks for trying, Brett.

Do you feel I described the "high points" clover correctly?

>> This would be an appropriate topic for the pilot's
>>meeting.
>>
>> Brett
>
>Crap. I was going to go practice chipping.

Might as well. You'd be crazy to wait until Tuesday afternoon and then go out and try to "fix" it from whatever you were doing before.

>
>Thanks for trying, Brett.
>
>Do you feel I described the "high points" clover correctly?

Not altogether. You focused on the dimensions. Making it look symmetrical, with the round parts round, and the straight parts straight, and hitting the intersections, is a lot more important than the dimensions.

>>Do you feel I described the "high points" clover correctly?
>
> Not altogether. You focused on the dimensions. Making it
>look symmetrical, with the round parts round, and the
>straight parts straight, and hitting the intersections, is a
>lot more important than the dimensions.

These points are considered a given.

'zilla--

Keith's excellent re-description puts some good math on what may have been an educated SWAG.

However, even the prior description had it that the tops of the loops on each side of the center line touch what would be the track of a wingover flown cross-wind. That offsets the higher loops, and being offset, they are not going to stay in half the hemishpere if they are 45º tall.

The rule proposal loks good for approval and inclusion in the next rulebook. We can start by "interpreting" present rules the new way, and -- as Brett wrote -- it is a good item for the pilot's briefing.

Judges view or pilots view. BIG DIFERANCE

Scott (like the old way ) Riese

MY way is a perfect example for the judges to score 40 pts. Other interpretations get 10 pts. Is that clear enuf?
Sammy

>Judges view or pilots view. BIG DIFERANCE
>
>Scott (like the old way ) Riese

The current rulebook on the four leaf clover is quite clear, even if it is impossible to fly the maneuver as described because of the incorrect altitude specified in the rule book for the horizontal intersections. The rulebook description is not dependent on the judge's view or the pilot's view. There are three basic elements regarding the size of the four leaf clover in addition to the symmetry, shape of the rounds, and straight intersections as Brett correctly mentioned.

The bottom two loops are to be tangent to the 4 to 6 foot normal flight altitude, while the top two loops are to be tangent to the vertical plane through the circle center. All four loops are to be the same size with the right loops tangent to the left loops along a vertical plane of symmetry through the center of the maneuver while the bottom loops are tangent to the top loops.

If the maneuver is started at the "approximate" 38 degree elevation and if all of the loops are to be the same size, the tops of the top loops will not come close to the tangent points of the vertical plane through the center of the circle. If the tangency requirements are met and the maneuver starts at 38 degrees, the loops cannot be the same size. For the loops to be the same size and to satisfy the tangency requirements at the bottom and top of the maneuver, the entry altitude needs to be approximately 42 degrees. (That is why the proposal for the approximate 42 degree horizontal elevation was submitted.) I think we have seen the attempt to make the entry to appear close to 38 degrees (current rule book) and for the loops to look the same size, we have become so accustomed to see overly small loops (even less than 38 degrees) and the tops not even close to reaching that vertical plane through the circle center that we have accepted the overly small loops as the way the manevuer is supposed to be flown. Typically, even some of the better flyers fly the entire four leaf clover in front of them with the tops not close to being directly above their shoulders. The really good flyers make the loops appear to be the same size, while putting the tops very close to being over their shoulders while the horizontal intersection is noticeably less than 45 degrees. It is the judge's responsibility to interpret what he sees from his perspecive on how well the pilot matches the rule book requirements.

I will not mention any names this close to the Nats, but there will be a handfull of flyers there that fly their four leaf clovers this way and they should get top scores for the manuever by doing so from most if not all of the experienced judges.

>If the maneuver is started at the "approximate" 38 degree
>elevation and if all of the loops are to be the same size,
>the tops of the top loops will not come close to the tangent
>points of the vertical plane through the center of the
>circle. If the tangency requirements are met and the
>maneuver starts at 38 degrees, the loops cannot be the same
>size.
I think we have seen
>the attempt to make the entry to appear close to 38 degrees
>(current rule book) and for the loops to look the same size,
>we have become so accustomed to see overly small loops (even
>less than 38 degrees) and the tops not even close to
>reaching that vertical plane through the circle center that
>we have accepted the overly small loops as the way the
>manevuer is supposed to be flown.

That is what we see.

So, are these flyers going to be down-graded or not?

The really good flyers make the loops
>appear to be the same size, while putting the tops very
>close to being over their shoulders while the horizontal
>intersection is noticeably less than 45 degrees. It is the
>judge's responsibility to interpret what he sees from his
>perspecive on how well the pilot matches the rule book
>requirements.
>
>I will not mention any names this close to the Nats, but
>there will be a handfull of flyers there that fly their four
>leaf clovers this way and they should get top scores for the
>manuever by doing so from most if not all of the experienced
>judges.

Little frustrated by this one, it only seems to go in a round.

Thanks anyway.

The really good flyers make the loops
>appear to be the same size, while putting the tops very
>close to being over their shoulders while the horizontal
>intersection is noticeably less than 45 degrees.

3 degrees? That is "noticable". Especially from 150 ft away?

as a judge, I look for a cloverleaf that starts a bit below 45 degrees(I can't tell 42 from 38 really) All four loops should be the same size and tangent, and the pilot shouldn't go back over his head. The hardest part is judging where the intersections should be, since there is no "marker"- the intersection is supposed to be on the entry level, but someplace a bit off to the left of the first loop. If the pilot gets the size right and the intersection, the straight parts almost have to be right just to make it fit.

I just watched about 40 cloverleafs at the GSCB contest(as a spectator not a judge). Virtually all of them started too low, the first loop was too big, and as a result the intersection was totally screwed up. Several guys did the cloverleaf below about 60 degrees- nice symmetrical shape, but way too small. I have no idea how the judges scored them though.

>as a judge, I look for a cloverleaf that starts a bit below
>45 degrees(I can't tell 42 from 38 really) All four loops
>should be the same size and tangent, and the pilot shouldn't
>go back over his head.

The "bit below 45 degrees" is where the problem comes in. Everybody knows that the maneuver is supposed to start below 45, and that the loops are supposed to be smaller, so the judges and coaches are watching for a noticable difference. The pilots, being obliging sorts, give them something noticably lower. Unfortunately, to be noticable, it has to be a lot more than 7 degrees (~8 feet, or two fuse lengths) different, hence the low entries (compared to the "45" point) and tiny lower loops.

Now, assuming the proposal passes, it's only 3 feet different, but I predict that the lower loops will quickly become to small again, in response to the need to provide a noticable difference. Actually, the firsft few years, people will make the entry noticably *high* to emphasize the difference from the old rules, then later make them smaller again to get the 3 degrees smaller to be noticable.

I also predict that, while people are worried about 1/2 a fuselage difference in the size, that some people will concentrate instead on making it symmetrical, and well-defined, and clean up over those obsessing over the maneuver description.

This is a *hallmark* example of the overemphasis of the seemingly (although not really) "objective" standards for trivial matters.

> I also predict that, while people are worried about 1/2
>a fuselage difference in the size, that some people will
>concentrate instead on making it symmetrical, and
>well-defined, and clean up over those obsessing over the
>maneuver description.
>
> This is a *hallmark* example of the overemphasis of the
>seemingly (although not really) "objective" standards for
>trivial matters.
>
> Brett

This is what I was trying to say about those who fly the better four leafs will have the loops all the same size, will come close to the tangency requirements, will have round loops and straight intersections. And those loops will be noticeably bigger than what has become the "accepted norm" here in the States as they should be anyway.

>
>3 degrees? That is "noticable". Especially from 150 ft
>away?

Not really, but it is definitely less than what most have become accumstomed to be called 45 degrees and it is definitely higher than the entry point of what many fly into the entry to be "approximately" 38 degrees at the entry of their four leaf.

In general, I think here in the States that we have accepted something to be less than 38 degrees as the entry point for the four leaf clover and really small loops for the entire clover as the way the four leaf is to be flown. They do not do it that way in Europe. And I know our team generally lost points on the four leaf clovers when they flew last Summer in Sebnitz. Bill Werwage flew his four leafs, with all the loops appearing to be the same size and the tops as near that vertical plane through the circle center as anybody, and he got good scores for his four leaf clovers.

To answer the question, how do you judge a 4-leaf with the ambiguity with the improper horizontal intersection altitude. Here is my opinion and this is the way I have discussed it at several clinics that I have conducted.

The judge should look for all four loops to appear to be the same size. The judge should look for the two bottom loops to be tangent to the equator of the hemisphere (the 5 foot altitude) and for the top loops to be tangent to the verticle plane through the circle center. (This, in addition to looking for shapes, other loop tangency requirements, intersection positions and straight flight paths through the intersections.) If a pilot hits those tangent points, his horizontal intersections will be something greater than the 38-degrees specified in the rule book but will still be something significantly less than 45 degrees. Nontheless, the four leaf clover will have been performed better than what we have become accustomed to see where the loops are often much less than 38 degrees with the top of the maneuver well in front of the pilot which is wrong.

I think this description is a more accurate portrayal of how the four leaf clover is to be flown than when we see the overly small loops being flown because the pilot is below even the 38 degree elevation to start the four leaf to show that he is really below something less than 45 degrees.