US club class definition

On Tuesday, January 31, 2017 at 8:28:26 PM UTC-8, Sierra Whiskey wrote:
I always find it hard to believe that an LS-8, ASW-28, and Discus 2 are considered "club" class. Seems a little modern and pricey for the average "club". Those are considered the top gliders of their own class (Standard) and are on the club class list among other aircraft that cannot claim the same merit.

Over time the Club class drifts downward in handicap (or upward if you're looking at FAI handicaps which are inverted from US). It's just a question of timing. I suspect it won't be long before all Standard Class gliders show up on the FAI list.

The gliders that go into Club are based on a tradeoff between two considerations: critical mass of non-handicapped classes and having tight clustering of the Club handicap range. Standard Class is on the edge of viability as a standalone Class and the latest generation of Standard Class gliders are effectively out of production so in the US we've elected to give racers who own these gliders the option to race in Club.

In many ways Club Class is a misnomer in the US because there aren't likely enough Club Class gliders actually owned by clubs in the US to populate a contest. The few that are owed by clubs are typically not easy to take to contests. These gliders are mostly owned by individuals and syndicates. The situation in many other countries is quite different, with a lot more race-ready gliders owned by Clubs and actually available to race.

9B

I like the explanation of "Club Class" on the FAI site:
"The Club Class arose to provide international level competition in club-type gliders for the large number of talented pilots who could not aspire to owning an expensive modern glider of their own. It has kept demand high for a number of older but still very valid designs."

Of course the term "Expensive" is relative, but the current US Club Class list spans roughly $10,000-$80,000 where the FAI list is much narrower.

My Two Cents:
If the handicapping of gliders were quantifiable through the use of a formula that accounted for the performance of the glider in order to actually level the playing field of the aircraft and allow for a measure of the pilot then the introduction of modern gliders to the class would make more sense. Correct me if I am wrong, but for over a decade the US handicap system has been more of an arbitrary assignment than a calculation.

I look at the Std. Cirrus compared to the LS-8. Their US Handicaps respectively are 1.0 and 0.915. To me this would imply that the LS-8 is 8.5% "better" than a Standard Cirrus. (Better is not the best descriptor, but is meant to be a summary of glide performance and speed).

Lets assume that the two gliders mentioned above are flying at Best L/D.
LS-8: 43:1 at about 50 kts
Std. Cirrus: 36.5:1 at 50 kts
I calculate the difference in performance by looking at a multiple of the GR*V_(L/D). Since in this case the V_(L/D) is the same we can omit them, and just compute (36.5/43) which gives 0.849.

The numbers above are a bit crude because they are pulled from various sources online. Even the LS-8 data is "Calculated" and the tested data is slightly different. Looking at it from other sources:
LS-8: 43:1 at about 50 kts
Std. Cirrus: 38:1 at 50 kts
This still gives the LS-8 an advantage of 0.884.

In a final "base" example I will use some extreme numbers, degrading the performance of the LS-8, and exaggerating the performance of the Standard Cirrus:
LS-8: 42:1 at about 50 kts
Std. Cirrus: 38.5:1 at 50 kts
We finally arrive at an advantage of 0.917! (I take this as a "Factory New Std. Cirrus" flying against a "Buggy LS-8 without Gap Seals"?)

The above examples would be great if we flew contests while flying at Best L/D speed over three hour courses of 150 miles. The fact of the matter is we are frequently pushing MacCreedy "2" speeds on four hour courses that exceed 240 miles. (Let's compare the performance at 60 kts)

Since I don't have either of these factory polar curves to use, again, I am coming up with crude numbers, but I still think they speak volumes. These are a comparison of the L/D at a constant sink rate (2 m/s):
LS-8: 24:1 at about 92 kts (92*24=2,208)
Std. Cirrus: 22:1 at 86 kts (22*86=1,892)
Now we have a performance comparison at a more representative cruise speed in competition with a yield of 0.857 in favor of the LS-8. This means at a target MacCreedy speed I would expect the LS-8 to perform roughly 14% more efficient than the Standard Cirrus assuming the exact same pilot in the exact same point (Position/Altitude). This seems to be quite far from the 8.5% advantage given by the current Handicap List.

Does anyone have any information on how the current US handicaps are derived? I would really like to see what performance numbers were used to calculate the level playing field numbers that we currently use.

Thank you for any help or pointing me in the right direction! Only one of my calculations even come close, and it seems to be an extreme example!

On Thursday, February 2, 2017 at 7:58:01 AM UTC+3, Sierra Whiskey wrote:
I like the explanation of "Club Class" on the FAI site:
"The Club Class arose to provide international level competition in club-type gliders for the large number of talented pilots who could not aspire to owning an expensive modern glider of their own. It has kept demand high for a number of older but still very valid designs."

Of course the term "Expensive" is relative, but the current US Club Class list spans roughly $10,000-$80,000 where the FAI list is much narrower.

My Two Cents:
If the handicapping of gliders were quantifiable through the use of a formula that accounted for the performance of the glider in order to actually level the playing field of the aircraft and allow for a measure of the pilot then the introduction of modern gliders to the class would make more sense. Correct me if I am wrong, but for over a decade the US handicap system has been more of an arbitrary assignment than a calculation.

I look at the Std. Cirrus compared to the LS-8. Their US Handicaps respectively are 1.0 and 0.915. To me this would imply that the LS-8 is 8.5% "better" than a Standard Cirrus. (Better is not the best descriptor, but is meant to be a summary of glide performance and speed).

Lets assume that the two gliders mentioned above are flying at Best L/D.
LS-8: 43:1 at about 50 kts
Std. Cirrus: 36.5:1 at 50 kts
I calculate the difference in performance by looking at a multiple of the GR*V_(L/D). Since in this case the V_(L/D) is the same we can omit them, and just compute (36.5/43) which gives 0.849.

The numbers above are a bit crude because they are pulled from various sources online. Even the LS-8 data is "Calculated" and the tested data is slightly different. Looking at it from other sources:
LS-8: 43:1 at about 50 kts
Std. Cirrus: 38:1 at 50 kts
This still gives the LS-8 an advantage of 0.884.

In a final "base" example I will use some extreme numbers, degrading the performance of the LS-8, and exaggerating the performance of the Standard Cirrus:
LS-8: 42:1 at about 50 kts
Std. Cirrus: 38.5:1 at 50 kts
We finally arrive at an advantage of 0.917! (I take this as a "Factory New Std. Cirrus" flying against a "Buggy LS-8 without Gap Seals"?)

The above examples would be great if we flew contests while flying at Best L/D speed over three hour courses of 150 miles. The fact of the matter is we are frequently pushing MacCreedy "2" speeds on four hour courses that exceed 240 miles. (Let's compare the performance at 60 kts)

Since I don't have either of these factory polar curves to use, again, I am coming up with crude numbers, but I still think they speak volumes. These are a comparison of the L/D at a constant sink rate (2 m/s):
LS-8: 24:1 at about 92 kts (92*24=2,208)
Std. Cirrus: 22:1 at 86 kts (22*86=1,892)
Now we have a performance comparison at a more representative cruise speed in competition with a yield of 0.857 in favor of the LS-8. This means at a target MacCreedy speed I would expect the LS-8 to perform roughly 14% more efficient than the Standard Cirrus assuming the exact same pilot in the exact same point (Position/Altitude). This seems to be quite far from the 8.5% advantage given by the current Handicap List.

Does anyone have any information on how the current US handicaps are derived? I would really like to see what performance numbers were used to calculate the level playing field numbers that we currently use.

Thank you for any help or pointing me in the right direction! Only one of my calculations even come close, and it seems to be an extreme example!

BGA has them at 90 and 100, so 10% or 11.1% different depending on which way you look at it.

The problem with these is one number can't apply across all conditions, especially with gliders so far apart in performance and generation.

On strong days, the LS8 is obviously going to run away into the distance and win a three hour race by far more than twenty minutes.

But on a weak day where you can barely stay aloft and the thermals are weak and narrow? It might be a lot closer, maybe even close to equal.

There probably exist days when a Ka8 can beat an LS8. Not often, mind.

On Wednesday, February 1, 2017 at 11:58:01 PM UTC-5, Sierra Whiskey wrote:
[...]
My Two Cents:
If the handicapping of gliders were quantifiable through the use of a formula that accounted for the performance of the glider in order to actually level the playing field of the aircraft and allow for a measure of the pilot then the introduction of modern gliders to the class would make more sense. Correct me if I am wrong, but for over a decade the US handicap system has been more of an arbitrary assignment than a calculation.

I look at the Std. Cirrus compared to the LS-8. Their US Handicaps respectively are 1.0 and 0.915. To me this would imply that the LS-8 is 8.5% "better" than a Standard Cirrus. (Better is not the best descriptor, but is meant to be a summary of glide performance and speed).

Lets assume that the two gliders mentioned above are flying at Best L/D.
LS-8: 43:1 at about 50 kts
Std. Cirrus: 36.5:1 at 50 kts
I calculate the difference in performance by looking at a multiple of the GR*V_(L/D). Since in this case the V_(L/D) is the same we can omit them, and just compute (36.5/43) which gives 0.849.

The numbers above are a bit crude because they are pulled from various sources online. Even the LS-8 data is "Calculated" and the tested data is slightly different. Looking at it from other sources:
LS-8: 43:1 at about 50 kts
Std. Cirrus: 38:1 at 50 kts
This still gives the LS-8 an advantage of 0.884.

In a final "base" example I will use some extreme numbers, degrading the performance of the LS-8, and exaggerating the performance of the Standard Cirrus:
LS-8: 42:1 at about 50 kts
Std. Cirrus: 38.5:1 at 50 kts
We finally arrive at an advantage of 0.917! (I take this as a "Factory New Std. Cirrus" flying against a "Buggy LS-8 without Gap Seals"?)

The above examples would be great if we flew contests while flying at Best L/D speed over three hour courses of 150 miles. The fact of the matter is we are frequently pushing MacCreedy "2" speeds on four hour courses that exceed 240 miles. (Let's compare the performance at 60 kts)

Since I don't have either of these factory polar curves to use, again, I am coming up with crude numbers, but I still think they speak volumes. These are a comparison of the L/D at a constant sink rate (2 m/s):
LS-8: 24:1 at about 92 kts (92*24=2,208)
Std. Cirrus: 22:1 at 86 kts (22*86=1,892)
Now we have a performance comparison at a more representative cruise speed in competition with a yield of 0.857 in favor of the LS-8. This means at a target MacCreedy speed I would expect the LS-8 to perform roughly 14% more efficient than the Standard Cirrus assuming the exact same pilot in the exact same point (Position/Altitude). This seems to be quite far from the 8.5% advantage given by the current Handicap List.

What phase of competition flight, often comprising nearly half the total time on course, have you left out? How much distance and speed is made during this phase? How different are the LS-8 and Std Cirrus during this phase? Does this affect your analysis at all :-)?

best,
Evan

No argument there, it is difficult to quantify the climb performance utilizing upward moving air. This would take some evaluation of the wing loading and sink rate at thermaling speeds.

That in mind, the analysis of speed and sink comparisons does indicate that if those two gliders left the same thermal at the same altitude and at the same time, the lower performing glider would arrive at the same next thermal lower and after the higher performing glider. Any delta in the climb performance (if one could be accurately calculated) would be negated by the point of arrival in the next thermal. So in a way the climb performance of the glider is accounted for in the calculation, probably as an under-estimate..

The above is probably why it is also so difficult to handicap variable ballasted gliders!

A while back I developed a plan to create a variable handicap where a Contest Director (with the help of the Weather Adviser) would declare three components to the race: Task, MacCready Value for the day, and a wind value for the day. Each handicap for the day would be based on the sink rate of each glider at the given MC and Headwind Values defined for the day. The idea was to level the playing field between a PW-5 and an ASG-29 across the different soaring conditions.

Examples:
1) Strong Lift- ASG-29 will cruise much further and more efficiently than a PW-5
2) Weak Lift- PW-5 will climb and stay aloft much easier.
3) Heavy Wind- ASG-29 has much better penetration into a strong headwind.

The reality is that the development of this system would take a significant amount of time due to a lack of high resolution data for glide performance across the spectrum of aircraft. Though the solution is difficult to design and implement, it would provide a better system to handicap gliders based on the soaring conditions, and not just a single performance value. The negative impact of this system is the requirement for rules protecting the CD from making a less than desirable call on the day values, and would introduce some new soaring strategy to optimize the performance of each aircraft based on the variable handicap for the given conditions.

This all came about while I was trying to determine how each glider's handicap is calculated. Unfortunately I am still unclear on how that happens.

On Tuesday, January 31, 2017 at 10:28:26 PM UTC-6, Sierra Whiskey wrote:
I always find it hard to believe that an LS-8, ASW-28, and Discus 2 are considered "club" class. Seems a little modern and pricey for the average "club". Those are considered the top gliders of their own class (Standard) and are on the club class list among other aircraft that cannot claim the same merit.

FAI is considering a proposal at their upcoming meeting to further expand the FAI definition. The proposal does not change the handicap range but it does propose to allow water ballast in the club class and set a maximum weight. The goal of this proposal apparently is to shift the range of competitive gliders up.

Read all about it. Let your IGC representative know what you think.

http://www.fai.org/downloads/igc/IGC...genda_Ax8_2_10

On Wednesday, 1 February 2017 14:58:21 UTC+2, Tony wrote:

FAI is considering a proposal at their upcoming meeting to further expand the FAI definition. The proposal does not change the handicap range but it does propose to allow water ballast in the club class and set a maximum weight. The goal of this proposal apparently is to shift the range of competitive gliders up.

Read all about it. Let your IGC representative know what you think.

http://www.fai.org/downloads/igc/IGC...genda_Ax8_2_10

Same Cirri/Libelle/etc. will fly the competition, only now with ballast. Current scoring system dictates that you have to fly together with other pilots, so you need to have same performance glider as others. This fact does not change with water ballast.

Regarding modern standard class gliders such as LS8 in Club Class, my opinion is that given an appropriate handicap factor, they may be perfectly acceptable provided ballasting is prohibited (as it is in the FAI definition of the class).
FAI leaves a lot of freedom about national rules for the gliders eligible in club class events (excluding those sanctioned by FAI at world or continental level).
In Italy we strictly apply the "IGC club class handicap list" which includes small adjustments for wingloading (think: Discus bT, PIK20E). The actual handicap for a single sailplane after the adjustments shall not exceed the max. accepted hcap factor indicated in the class definition.

Aldo Cernezzi

"... I, for one, have no interest in handicap soaring (or sailing) "competition."

Although this is a part of the tome on handicapping it is interesting that he is on the standby list for next month's Senior's.

Maybe he thinks running his ASG-29 against such as Silents without handicapping could improve his chances?

KS

Karl does your new duo have its nose wheel?

;-)