Results of Flight Performance Determination of the Lak‐17a FES

[Renny]

Based on some previous postings on the FES and the questions regarding the drag effects of the FES propeller blades, attached for everyone's info is a URL to the final Idaflieg FES testing report dated Feb 21,2014.

http://www.front-electric-sustainer.com/Documents/IDAFLIEG%20test%20LAK17A%20FES_en.pdf

Keep in mind that this evaluation was done on a LAK-17a FES. For new LAK gliders FES installations at the LAK factory are being done on the LAK-17b and more recently, an FES installation was done on a LAK-19.

As many of you are also aware, the FES is available on the Alisport Silent 2 Electro.

Thx - Renny

[Sean F (F2)]

Looks like 2-4% to me from the L/D diagrams. Very significant. Handicap committee?

Sean

[anderson....@gmail.com]

On Monday, February 24, 2014 7:20:13 AM UTC-8, Sean F (F2) wrote:
> Looks like 2-4% to me from the L/D diagrams. Very significant. Handicap committee?
>
> Sean

Here you go:

http://www.ssa.org/files/member/RulesCommitteeProceedures_Rev1.PDF

Something to consider for 2015. The window for making changes is closed for 2014.

FAA Registration Database shows 2 LAK-17B FES registered in the US (no A models - is there a difference?). One is registered in FL - the registered owner shows up in SC for SSA records. The other one is in New Mexico. Neither registered owner has flown in a contest since 2005 according to SSA.

Maybe some FES models are coming to contest pilots in 2014? If so, they will need to fly with the normal LAK-17A handicap - if they fly in a handicapped class.

9B

[Steve Leonard]

On Monday, February 24, 2014 9:20:13 AM UTC-6, Sean F (F2) wrote:
> Looks like 2-4% to me from the L/D diagrams. Very significant. Handicap committee? Sean

Don't forget the adjustment the other direction for the higher weight. There is a formula for that, too, Sean.

[Sean F (F2)]

My initial goal was to press home that the FES system (blades, etc) has a significant impact in aerodynamic performance (drag) over the exact same glider without FES I think that it is now clear that a credible study has shown FES performance degradation that is both measurable and significant.

I'm not sure why I should have to fill out a form for action to happen?

While there may only be 2 Lak17b FES in the US at current, there are also others in Canada. A re-factored handicap may encourage a few more!

Can someone from the handicap committee do the "rough math" (assume 2-4% drag) on the Lak17bFES handicap with a 75 lbs increase weight. Does that result in a handicap?

What is the equation or equation set used to create a handicap? Or is it a subjective process?

Thanks, Sean

[Steve Leonard]

On Monday, February 24, 2014 12:04:10 PM UTC-6, Sean F (F2) wrote:
> My initial goal was to press home that the FES system (blades, etc) has a significant impact in aerodynamic performance (drag) over the exact same glider without FES I think that it is now clear that a credible study has shown FES performance degradation that is both measurable and significant. I'm not sure why I should have to fill out a form for action to happen? While there may only be 2 Lak17b FES in the US at current, there are also others in Canada. A re-factored handicap may encourage a few more! Can someone from the handicap committee do the "rough math" (assume 2-4% drag) on the Lak17bFES handicap with a 75 lbs increase weight. Does that result in a handicap? What is the equation or equation set used to create a handicap? Or is it a subjective process? Thanks, Sean

How about if you please relax, take a deep breath, and allow more than three hours between the posting of a link to performance data and publication of a revised handicap number? The drag difference has been presented. There is a standard method applied to correct for weights above initial handicap weight. It is in the rules. Please permit enough time to elpase so that those on the handicap committee at least have a chance to be informed of the data, review it, and provide some sort of comment to the competition committee relative to a change in handicap for this plane, if they believe one is needed.

[Steve Leonard]

On Monday, February 24, 2014 9:57:37 AM UTC-6, anderson....@gmail.com wrote:
> The window for making changes is closed for 2014.

> 9B

FWIW,9B, I have seen handicap changes in mid year.

ZS

[uncl...@ix.netcom.com]

On Monday, February 24, 2014 1:04:10 PM UTC-5, Sean F (F2) wrote:
> My initial goal was to press home that the FES system (blades, etc) has a significant impact in aerodynamic performance (drag) over the exact same glider without FES I think that it is now clear that a credible study has shown FES performance degradation that is both measurable and significant. I'm not sure why I should have to fill out a form for action to happen? While there may only be 2 Lak17b FES in the US at current, there are also others in Canada. A re-factored handicap may encourage a few more! Can someone from the handicap committee do the "rough math" (assume 2-4% drag) on the Lak17bFES handicap with a 75 lbs increase weight. Does that result in a handicap? What is the equation or equation set used to create a handicap? Or is it a subjective process? Thanks, Sean

This is a discussion group that facilitates exchange of information and ideas.
It is not in any way a formal part of the competition rules process.
If you have a request of the rules or handicap committees you should make that request directly to them.
Skewering volunteers in the hope of accomplishing your objective will accomplish nothing.
The polar information referenced will be useful in allowing the handicap folks a chance to project expected cross coutry speed and create an appropriate handicap.
UH

[soa...@gmail.com]

By the way don't we need two sets of handicaps one adjusting for the weight for sports class and one not adjusting for the weight for FAI handicap contests with water?

[Sean F (F2)]

I had no intention of skewing volunteers! Just trying to understand the process. Yes I am passionate about the Lak17b FES. I assumed (wrongly) that the HC was a more proactive body.

Social media and even Google Groups seem to be a much easier way to ask questions than emailing. Perhaps the SSA Handicap Committee could consider creating a Google Group or... (hold on to your chairs) even a Facebook group?

Social is a much more efficient means of communication and open discussion that email for sure. Facebook groups for example can be private and each member can be approved once credentials are confirmed.

Just a thought.

Sincerely,

Sean

[Sean F (F2)]

Some guidance on the Lak17bFES contest results here (look at 18 meter overall middle of page):

http://www.wgc2012uvalde.us/index.php?option=com_content&view=article&id=110&Itemid=7#18M

My understanding is that these were fairly accomplished pilots. Clearly the FES is not "helping!"

[Kevin Christner]

Based upon these "results" the handicap of a LAK-17 FES should be 31% lower than an ASG-29. I'm sure we can agree that is not accurate. Perhaps you should do the math before spouting an opinion.

[Kevin Christner]

On Monday, February 24, 2014 4:40:22 PM UTC-5, Sean F (F2) wrote:
> I had no intention of skewing volunteers!

Actually that is exactly what you intended. Since us mere mortals could never live up to your standards, we must be roasted over an opinion fire to make an example of us so know when will question Sean, the god of gliding knowledge!

[Ramy]

I am not a competition pilot myself but find it absurd that a glider with FES will get better handicap than one without due to loss of 1 point in glide performance. Surely the advantage of self retrieve outweight 1 point in glide. Otherwise just take the blades off during the contest.

Ramy

[uncl...@ix.netcom.com]

On Monday, February 24, 2014 4:40:22 PM UTC-5, Sean F (F2) wrote:
> I had no intention of skewing volunteers! Just trying to understand the process. Yes I am passionate about the Lak17b FES. I assumed (wrongly) that the HC was a more proactive body. Social media and even Google Groups seem to be a much easier way to ask questions than emailing. Perhaps the SSA Handicap Committee could consider creating a Google Group or... (hold on to your chairs) even a Facebook group? Social is a much more efficient means of communication and open discussion that email for sure. Facebook groups for example can be private and each member can be approved once credentials are confirmed. Just a thought. Sincerely, Sean On Monday, February 24, 2014 4:00:39 PM UTC-5, uncl...@ix.netcom.com wrote: > On Monday, February 24, 2014 1:04:10 PM UTC-5, Sean F (F2) wrote: > > > My initial goal was to press home that the FES system (blades, etc) has a significant impact in aerodynamic performance (drag) over the exact same glider without FES I think that it is now clear that a credible study has shown FES performance degradation that is both measurable and significant. I'm not sure why I should have to fill out a form for action to happen? While there may only be 2 Lak17b FES in the US at current, there are also others in Canada. A re-factored handicap may encourage a few more! Can someone from the handicap committee do the "rough math" (assume 2-4% drag) on the Lak17bFES handicap with a 75 lbs increase weight. Does that result in a handicap? What is the equation or equation set used to create a handicap? Or is it a subjective process? Thanks, Sean > > > > This is a discussion group that facilitates exchange of information and ideas. > > It is not in any way a formal part of the competition rules process. > > If you have a request of the rules or handicap committees you should make that request directly to them. > > Skewering volunteers in the hope of accomplishing your objective will accomplish nothing. > > The polar information referenced will be useful in allowing the handicap folks a chance to project expected cross coutry speed and create an appropriate handicap. > > UH

If you have input for the RC, or the HC for that matter, the time needed to organize your thoughts and any supporting information is and order of magnitude greater that that needed to do the e-mail itself.
If it is not worth taking the time to thoughtfully put the input together, it certainly would not be worth much of their time to consider it. Every e-mail sent to the RC should, and as far as I recall when chair did, get a response and was added to the list of topics to be considered when putting together the annual rules change agenda.
UH

[Sean F (F2)]

just look at the current handicap boys and girls, which is equal for pure and FES. is that what it needs to be? you tell me HC.

god of soaring? wow, thanks? take a pill there pal. you'll feel better soon. WTH?

[ZL]

On 2/24/2014 7:17 PM, Sean F (F2) wrote:
> just look at the current handicap boys and girls, which is equal for pure and FES. is that what it needs to be? you tell me HC.
>
> god of soaring? wow, thanks? take a pill there pal. you'll feel better soon. WTH?
>

Have you looked recently? Current handicaps from the SSA web page on 2/24/14

AB Sportine Aviacija LAK-17B W 18 868 0.845
AB Sportine Aviacija LAK-17B FES MW 18 998 0.835

Keep in mind the handicaps are for sports class, no disposable ballast.
So they think the extra weight allowed more than makes up for the extra
drag.

I wonder if there is a handicap adjustment for removing FES blades like
there is for aftermarket wing root fairings or turbulators?

[Sean F (F2)]

people. please stop trying to add a handicap PENALTY to a glider on the merits of it having a motor and folding propellers on the nose. nothing in the rules considers a motor as a performance advantage. there is no precedent for it. if there is i challenge you to name it. the idea of a penalty for being a motor-glider is absurd. an asg29e does not get an additional handicap penalty because it has a motor last i checked.

the only fact that will be considered here is that there is a CLEAR performance degradation (significant and for OBVIOUS reasons) for gliders equipped with the FES system on the nose of the aircraft. the FES glider has more drag, PERIOD. look at the performance charts. the glider suffers this drag penalty every second it flies vs. the pure version. the idea that a motor somehow provides an advantage is subjective fantasy. no other motor-glider gets a penalty for being a motor-glider alone. again this logic is absurd. but please, show us your examples.

handicaps are based on performance data and gross weights, PERIOD.

this is what we are discussing here. PERIOD.

lets focus on facts here and standard procedures for handicap assignment... PERIOD.

[Sean F (F2)]

ill bet money that handicap is only based on weight differences.

HC, please describe how this handicap was calculated? was there any aerodynamic (see study) considerations? or is this handicap based purely on 75 lbs additional mass?

[ZL]

On 2/24/2014 7:37 PM, Sean F (F2) wrote:
> ill bet money that handicap is only based on weight differences.
>
> HC, please describe how this handicap was calculated? was there any aerodynamic (see study) considerations? or is this handicap based purely on 75 lbs additional mass?
>

Current scoring rules adjust handicap 2% per 100 lbs difference from
reference weight. The weight difference here is 130 lbs. Handicap
difference is 1 %. If you just showed up with a heavy 17B, the
adjustment would be 2.6%.

Theoretical increase in glide speed for 130 lbs extra in the LAK 17B is
> 7%.

I don't know what kind of thermal model the handicappers use to know
what kind of climb degradation they assume.

Also the spreadsheet version of the handicaps show it was updated in the
last week.

Sure, its not fair. No handicap is ever fair. But they are part of the
game in sports class.

[acm...@gmail.com]

the idea of a penalty for being a motor-glider is absurd. an asg29e does not get an additional handicap penalty because it has a motor last i checked.

the idea that a motor somehow provides an advantage is subjective fantasy. no other motor-glider gets a penalty for being a motor-glider alone. again this logic is absurd. but please, show us your examples.
>

Sean
I don't know where you have been the last 29 years, but the first sports class nationals was in 1985 and mg/sustainer versions have always had higher handicaps than pure gliders. Read the hc list first and then comment. ASG29e is .01 higher than ASG29. The additional wingloading is the advantage, not the motor, and these HC's have been working very well for a long time.
Rick Walters

[Sean F (F2)]

Rick,

My point is that there is no handicap penalty for "being a motor glider". The only factor that is measured in the handicap calculation is the additional weight of the motor equipment. The FES is a new situation in which it has both additional weight AND IMPORTANTLY it also has a significant, measured aerodynamic disadvantage which needs to be taken into consideration objectively when considering its handicap.

In this case, if you run the numbers, the FES handicap for the Lak17bFES is only considering the additional weight (75lbs not 135 I think boys). Regardless, no consideration or calculation has been factored in (current US handicap) to compensate for the aerodynamic drag penalty of the system (propellers, etc). These propellers effect the Lak17bFES performance each and every second it flies in contest flight. It should also be considered in the handicap ALONG WITH the extra weight.

I think the current handicap is incomplete and unfair to owners of the Lak17bFES and highly discouraging to potential new owners or those considering a modification to a current pure glider.

Sincerely,
Sean

[herbk...@gmail.com]

Duly noted, Sean. Way too much noise on a 2% handicap change that nobody besides yourself gives a flip about. A couple of years ago the handicap on my LS8 was changed from .925 to .915, no idea why. Rather than screaming like a little girl about it I just concluded that - just like a fine wine - my glider is getting better with age. No conspiracy here, Sean, move along.

Herb

[uncl...@ix.netcom.com]

On Tuesday, February 25, 2014 9:35:19 AM UTC-5, Sean F (F2) wrote:
> Rick, My point is that there is no handicap penalty for "being a motor glider". The only factor that is measured in the handicap calculation is the additional weight of the motor equipment. The FES is a new situation in which it has both additional weight AND IMPORTANTLY it also has a significant, measured aerodynamic disadvantage which needs to be taken into consideration objectively when considering its handicap. In this case, if you run the numbers, the FES handicap for the Lak17bFES is only considering the additional weight (75lbs not 135 I think boys). Regardless, no consideration or calculation has been factored in (current US handicap) to compensate for the aerodynamic drag penalty of the system (propellers, etc). These propellers effect the Lak17bFES performance each and every second it flies in contest flight. It should also be considered in the handicap ALONG WITH the extra weight. I think the current handicap is incomplete and unfair to owners of the Lak17bFES and highly discouraging to potential new owners or those considering a modification to a current pure glider. Sincerely, Sean

Then write to the handicap committee and make your case instead of campaigning on RAS which is not part of the process.
It appears to me, possibly incorrectly, that the report on this was only published very recently. I see a 1/14 date on it. If that is so, it was not really available as part of the HC consideration this year. Additionally, they would likely not be aware of it unless an affected person brought it up.
Use the process.
UH

[Sean F (F2)]

will do. thanks hank.

[Sean F (F2)]

Where can I find the contact info for the Handicap Commitee? I just looked on the SSA website and could not find anything. Did I miss it?

[Sean F (F2)]

Herb,
Thanks for your opinion. Brilliant as usual.
Sean

[Dave Leonard]

On Wednesday, February 26, 2014 8:26:59 AM UTC-7, Sean F (F2) wrote:
> Where can I find the contact info for the Handicap Commitee? I just looked on the SSA website and could not find anything. Did I miss it?

Direct link:
http://www.ssa.org/Volunteers

You will need to sign in.

Look for

Contest Handicapping Committee

Or through the menus

The SSA|About the SSA|Governance|Other Volunteer Committees

[Sean F (F2)]

Thanks Dave.

All, here is a video on the FES performance testing: https://www.youtube.com/watch?v=o0twY9cWOUg