ResultsÂ*ofÂ*FlightÂ*PerformanceÂ*DeterminationÂ*o fÂ*theÂ*Lakâ€�17aÂ*FES

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....A%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

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

Sean

On Monday, February 24, 2014 9:48:51 AM UTC-5, Renny wrote:
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....A%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

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/Rule...dures_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

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.

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

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.

On Monday, February 24, 2014 9:57:37 AM UTC-6, wrote:
The window for making changes is closed for 2014.
9B

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

ZS

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

On Monday, February 24, 2014 12:21:30 PM UTC-5, Steve Leonard wrote:
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.

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?

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, 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