Author Topic: ama speed chart (Read 1530 times)

Joey Mathison 9806 · « **on:** February 22, 2008, 05:47:51 PM »

i noticed that most of the speeds reported from the whitter contest over the last few years are not in the ama speed chart. anybody know why? do they have a new speed chart that i don't know about. for ex. pete soule has a web site that posted the fastest speeds for so cal contest in 2007 only 1 is on the speed chart. would really like some help in figuring out why this is.

Bill Hughes · « **Reply #1 on:** February 23, 2008, 10:05:34 AM »

Joey....Pete...the Brain that he is... is figuring the Speed without a Speed Chart....
He adds the 3 watches together. Then..without Truncating or Rounding Off the Average of the 3 Watches He plugs this in to the Calculations that are specified in the AMA Rule Book. Most of the time this changes the Final Speed by only a little bit. Maybe .0X MPH. But, in the case of the last A Speed Records....hum it changed things alot...The thing that you fellas, the Contrestants need to do is make sure that the Times are recorded and converted to MPH cortrectly...In the AMA Speed Rules, it does not say to use the Average Time to the nearest 1/100 sec for calculating the Speed in MPH. It does state this on the Record Application. Which I feel is the correct method.
Now, The Contests in LA/Whitter run by Pete Soule are the only Contests in the USA that are scored without rounding or truncating the Average of the 3 watches. The AMA Speed Chart listed on the Rule book is calculated by rounding off the average of the watches. Now, Pete wants ALL Speed Contests to be run using the Transistrace Electronic Timer. For now and the forseeable Future...that is impractical. The method that has been used thoughtout the USA for decades is good enough. The Control Line Speed Contest Board Charman (ME) is working on clearing a few of these typos and missed details in the Control Line Speed Section of the AMA Rule Book like this one.....But, it takes Time... IO hope this clears things up for you..By the way,,the A Speed Records were calculated correctly which when done were faster than Pete's method.
Bill Hughes
CLSCB Chairman

Joey Mathison 9806 · « **Reply #2 on:** February 23, 2008, 01:22:28 PM »

thanks Bill one of these days i hope to see the whitter contest get back to where they used to be. not following the rules ama has in print is a bit disturbing and i think it is time for a change as far as the shot caller at the whitter contest. when this mess is all cleared up i will be glad to return in particapting in the whitter contest.

dynasoar1948 · « **Reply #3 on:** February 23, 2008, 01:39:30 PM »

Bill and Joey,

I've kind of taken it for granted that the speed calculation method printed in CL Speed Rules-2007 (ST Oct -Dec 2006) was OK. This gives Vmph = 1799.28/ TIME in SEC, with time assumed to be the average of three stopwatches within 0.2 SEC. This uses the 0.01 SEC stopwatches and digital hand calculators that everyone uses these days, up from the tenth second watches and speed charts from the past.

That being said, I'd be glad to compete using any standardized timing method.

Lets say that next year somebody, me even, flys one of my Sport Jets and gets the following watch readings:

11.00 Sec 11.01 and 10.95, good close readings.

The average of the three watches is 32.96/3 = 10.98666..... Sec. What speeds can be calculated?

Truncated average 10.98 Sec- from AMA Speed Table 163.87 MPH
Rounded average 10.99 Sec- from Table 163.72 MPH

Using true unclipped average available on any calculator, and the 1799.28 constant from Speed Times, the ACTUAL speed is 163.769 MPH, which would truncate to 163.76 MPH or round to 163.77 MPH.

Which of these possible calculations should I make sure is used to record my flights?

Thanks, Will Stewart

Joey Mathison 9806 · « **Reply #4 on:** February 23, 2008, 02:15:00 PM »

163.77 and 163.76 are not in the ama speedchart that i have. to me the speeds recorded should be in the ama rule book period. weather it is right or wrong that is what we go bye. just because someone thinks they are smarter than the rule book and has there way of doing things is not going to cut it with me that is why i won't be at anymore whitter contest untill the problem is removed.

dynasoar1948 · « **Reply #5 on:** February 23, 2008, 03:05:26 PM »

Joey,

I didn't know there was a problem until just recently, and I want to know the Official way the contest people SHOULD calculate our speeds. Then I will be ready to raise an argument if the Official AMA method, whatever it is, is not used.

I know that the 1/2 Mile Speed Chart is not used any more for 1/2A or A or FIA, and that Constants divided by Average Watch Times are used in these classes. Maybe the problem is that AMA does not tell us how to compute this average watch time. I would think the average should be rounded to two decimal places. Bill has mentioned truncating the number- which means simply dropping off everything after the second decimal place. As I showed in my last message, these methods can result in different average times. Bill can tell us which way is the OFFICIAL method, instead of using the 1799.28 Constant for B,D, Jet etc. Just do it before the next contest, so Joey won't have to miss it.

I also believe that the next Speed Rule book should take into account what is in general use in electronic stop watches and hand calculators and allow the average as computed to be directly divided by 1/Constant to calculate speed. The speed read-out can then be rounded to the usual two decimal places. This will eliminate entry errors and rounding errors, as well as misreading the chart, which I've seen happen. (Also, the 0.2 Sec tolerance on watch readings is too large, since we now have 1/100 Sec watches. Maybe 0.1 Sec.)

Again, how do we get the two decimal places? Let me know and I'll make sure we do it that way.

Will

Paul Smith · « **Reply #6 on:** February 23, 2008, 03:26:30 PM »

If the arithmetic is sooooo hard, why not just process a rules change to score speed records purely by TIME, and not even convert to MPH? They could publish "approximate MPH" just for fun.

I liked the system at the WC in Holland several years ago. They counted laps with an automatic proximity system that counted ten laps and automatically and displayed KMPH on a scoreboard instantly - No HANDS, no reaction time.

With human beings in the loop, nothing will be any better than +/- .2 seconds.

Double Deuce · « **Reply #7 on:** February 24, 2008, 11:34:11 AM »

Think the answer to how times should be handled can be found on the backside of an AMA record application form. It seems to be pretty self explanatory. That it is there and not actually in the rule book is the root of the problem. A form can be downloaded from the AMA site if one is not familiar with the method, and it surely sounds like several folks are not.

The comment about just recording times was broached by yours truly probably 30 years ago and was promptly shot down because of folks "need to know what speed they turned." I would still support such a method, simply to remove the need for a lot of work when line lengths are changed. A rounding statement would still need to be applied, however.

Bill Hughes · « **Reply #8 on:** February 24, 2008, 01:47:19 PM »

1st, let me ask who you are Double Deuce? You are correct..the problem is that the Record Application language is not in the AMA CL Speed Section of the Rule Book. This should be a simple correction.

As to the other reply..from ama21835 (Phil?) stated:

I liked the system at the WC in Holland several years ago. They counted laps with an automatic proximity system that counted ten laps and automatically and displayed KMPH on a scoreboard instantly - No HANDS, no reaction time. This was the 1976 World Champs.

This is not entriely true. 3 Manual watches were used for the official results. The 1st time the Transistrace Electronic Timer was used OFFICAILLY was in Muncie at the 2004 World Champs. But, as I said before, this is impractical for all of the AMA Speed Contests around the USA.
Everyone please just calm down...

Bill Hughes
CLSCB Chairman AND F2A Team Selection Committee Chairman

dynasoar1948 · « **Reply #9 on:** February 24, 2008, 02:36:40 PM »

My last AMA CL Speed record forms were submittted in 1999, and had a much different format. The formula for calculating speed on the present form is ideal for contest use at the timers table. I've tried some sample
calculations and the speeds,so far, duplicate the Speed Chart, tho there may be some last decimal place round-off error possible. The 4.284 constant takes the place of all the others for different classes, as well as need for reference to the Speed Chart.

The AMA record formula for MPH (to nearest 1/100) is:

Line Length (in feet) X Number of laps X 4.284
_______________________________________
Average (to nearest 1/100 of the timer's watch reading in seconds)

The calculated average of the watch times (which could run to eight decimal places on hand calculators) must be rounded to the nearest 1/100 sec (this answers the "truncation" question raised earlier).

Would there be any problem if the official AMA record method of speed calculation is used for scoring all flights at Whittier? Bill? Joey?

If there is no problem with this, let me know and I'll do the arguing at this end to make it so.

Will Stewart

PS It would be clearer if the denominator was:

Time (Average of timers' watch readings rounded to nearest 1/100 Second)

Paul Smith · « **Reply #10 on:** February 24, 2008, 03:18:46 PM »

Actually, the olde practice of "rounding off" is an relic of the 20th century.

Today's computers can crunch all the numbers you've got, so shovel 'em in and let the micrcochips fall wher they may.

I have faith that ANY stopwatch you can buy, from $4 to $50,000 is equally accurate for a time span of 11 seconds, when actuated by the human thumb.

Double Deuce · « **Reply #11 on:** February 24, 2008, 04:48:39 PM »

Seems the wheels fell off when the formula Dynasoar quoted was NOT used at the WN contests of late. Had it been used, this total discussion would not be occurring.

The idea of letting the chips crunch the numbers has merit, if one can reconcile how that would match with ye old rulebook. Think maybe just fixing the readout on the calculator to two places, then let the chips get it on might be a legal approach? Certainly would have reduced a large amount of heartburn.

Until it is changed, right, wrong, or indifferent, the rulebook must be followed.

Bill Hughes · « **Reply #12 on:** February 24, 2008, 05:45:29 PM »

Hey D-Deuce...Thanks for the phone message...
Bill

Double Deuce · « **Reply #13 on:** February 24, 2008, 06:17:16 PM »

As I have a habit of approaching most subjects with an open mouth, please disregard my comment on item 11 concerning the fixed decimal. Talked myself into another corner. It will work for the time average but that number must then be entered into the formula for the speed to be legal. Two steps.

Good to hear from you Billy. Be careful

Joey Mathison 9806 · « **Reply #14 on:** February 24, 2008, 06:46:58 PM »

looks like it is time for me to scrap up my bag of worms and put them away i really hope they don't leave any permanate stains. hope to you all at the next whitter contest

don Burke · « **Reply #15 on:** February 27, 2008, 10:13:51 AM »

I really don't see what the big problem is. Mph is distance traveled divided by the time. Nothing too hard about that.

Pete and I worked together to get ACCURATE speeds calculated by a computer spreadsheet based on the average time of three stop watches, and the distance specified by the rule book. This distance is the number of laps times the circumference of the circle. This may or may not be EXACTLY 1/2 mile, 1/4 mile, 1 kilometer. But so be it, it is fact! The numbers may come out slightly different from the chart in the rule book. Got to remember that chart was probably created when slide rules and COMPTOMETERS were the best things available.

I just looked at the spreadsheet. The speed numbers as shown are rounded to two decimal places by the program.

Double Deuce · « **Reply #16 on:** February 27, 2008, 10:39:26 AM »

The problem with it all is trying to reconcile computer generated numbers to values presently considered to be the "standard". No where in the rule book does it state how the speeds should be calculated. It is, however, shown on the reverse side of the record application form. This form can be downloaded from AMA site for those not familiar with it. The AMA rule book is surely outdated, vague, incorrect and other bad words, BUT, it is still the official rule, til changed, updated, and other good words.

My record speed in class A at the TfT07 contest was recorded as 189.14 using computer generated numbers. I filed a speed of 189.21 using the formula on the record application sheet. The record was approved by AMA Hq. It was a matter of using an average time of 8.8333333 for the contest speed, and 189.83, rounded per formula given on the application. Think anyone would consider two speeds awarded to the same flight to be somewhat unsat.

In a record ratio contest(TfT07), comparing speeds turned under one system of figures(computer generated) against records established under another system(reverse side of the record app form) also strikes me as unsat.

Double Deuce · « **Reply #17 on:** February 27, 2008, 10:44:05 AM »

Again I misspoke. The 189.83 comment should read 8.83 See, I can't even write right, much less figure right. Damned Louisiana schools.

dynasoar1948 · « **Reply #18 on:** July 17, 2008, 09:19:43 AM »

Everybody!!!

The speed results from the AMA Nationals, on the actual AMA website are being presented to three (count 'em) decimal places!!!

What gives?

Dynasoar

john e. holliday · « **Reply #19 on:** July 17, 2008, 03:14:08 PM »

Why aren't you here to ask and find out. I don't know as I have been busy meeting people, selling and having a good time. Later, DOC Holliday

dynasoar1948 · « **Reply #20 on:** July 17, 2008, 09:46:00 PM »

Hey John, Sometimes the real world gets in the way. Wish I could be there with you guys playing, but I didn't plan my consulting deadlines far enough in advance. Maybe next year.

Dynasoar

Double Deuce · « **Reply #21 on:** July 19, 2008, 10:38:02 PM »

Ever notice how the person who asks a legitimate question automatically becomes the bad guy on these alleged forums?

I, too, would like to know just what happened in the fiasco called the U S Nationals, better known as the NASS show your *** contest. And I really don't think it is anyone's particular business as to why I was not there to find out for myself. Maybe the answer to the question will suffice to explain as to why I have flown my last Nationals. And why I am not and will not be a member of NASS.

The rule book, until changed, is still supreme.

Double Deuce