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Aug 17, 2019, 07:48 PM
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I've only had to share the field with power fliers a handful of times and agree it's a bit of a pain. I usually fly from a dedicated soaring field or from a rural high school with lots of room....as long as there aren't kids playing any number of sports. Football is starting back up so weeknights and Saturday mornings are going to become problematic again.
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Aug 17, 2019, 08:20 PM
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I was honestly surprised how well the bungee actually did! For some reason not nearly as nerve wracking as the winch
Aug 17, 2019, 09:51 PM
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Oh, the hi-start is always less nerve wracking. lol
My bungee is barely up to the task, but I throw it hard and I can get close to 200', which is enough some days.
Aug 18, 2019, 08:49 AM
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This just makes it more of a point for me to bring my bungee along with the winch each time I go to the field. Thinking a bungee would be much easier for guys to cope with.
Aug 25, 2019, 01:05 PM
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line length for these launches


Quote:
Originally Posted by GliderJim
Went out tonight and did some launches. Overcast skies, a bit breezy. I'm guessing a steady 10 mph. I'm getting less timid on the winch. With this much wind the tension on the line builds enough that when I go to full pedal at the top the winch barely turns. I've got one bad one in there, but that 252 foot zoom topping out at 580 feet was definitely fun.

1st Flight - 314 to 534 = 220
2nd Flight - 316 to 560 = 244
3rd Flight - 328 to 580 = 252
4th Flight - 354 to 538 = 184
5th Flight - 327 to 560 = 233
Thanks for your efforts and for posting this information. I read that you fly on an athletic field with a football field. For mixed launch contests, winch line length can be tricky to try to arrive at zooms that top out at the 150 meter (492 feet) cutoff for the motor in the nose models. Based on the 100 yard football field is the line length about the 400 feet you originally estimated?
Aug 25, 2019, 07:58 PM
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I pace out 160 steps to the turn-around. I estimate that to be "about" 400 feet. However, I flew at the S.O.A.R contest this weekend. They marked the winch and turn-around positions for us (it was bring your own winch) and I believe they used a range finder to set the distance. I also have launch data on my transmitter so I will get the distance and launch numbers and post them here.
Aug 25, 2019, 08:59 PM
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What is the maximum wind you guys would launch in? Had wind sustained 20mph and gusts around 35 or more. Obviously I am not going to personally launch, but being as it is always windy here in ND I need to get comfortable launching in higher winds.
Aug 25, 2019, 09:31 PM
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I'm guessing we were 10 sustained with gusts to 15 today. I suppose I would launch in 20 mph wind if it were right down the line and steady, but I don't know if I'd enjoy it.
Aug 26, 2019, 12:37 PM
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Long Post Alert

All of my data so far has been with my winch to turn-around pulley distance at 160 paces, which I estimated to be around 400 feet. I flew in a contest this weekend where the winch to turn-around distance was 150 meters (measured with an optical rangefinder). I paced it off and it was 190 paces.
150 meters = 492 feet = 190 paces
492/190 = 2.59 feet per pace.
160 paces * 2.59 = 414 feet.

Ok - so I was pretty close. 414 feet is the new number.

My best group of launches were on 8/14 in windy conditions. I averaged 554 feet (1.34 times winch to turn-around distance)
My average launch height on 7/1 in light winds was 500 feet (1.20 times winch to turn-around distance)

Here is the launch data from this weekend...

S.O.A.R. - Saturday - 8/24/2019
Winds 10 plus mph later in day
White Zenith

1st Flight: 367 to 562 = 195 feet
2nd Flight: 345 to 542 = 197 feet
3rd Flight: 400 to 655 = 255 feet (Launched into thermal)
4th Flight: 367 to 577 = 210 feet
5th Flight: 371 to 611 = 240 feet
6th Flight: 377 to 595 = 218 feet
7th Flight: 385 to 635 = 250 feet

Red Zenith
8th Flight: 341 to 581 = 240 feet
9th Flight: 388 to 623 = 235 feet (Launched into thermal)


S.O.A.R. Contest - Sunday - 8/25/2019
Winds 10 plus mph later in day
Red Zenith

1st Flight: 356 to 600 = 244 feet
2nd Flight: 350 to 612 = 262 feet
3rd Flight: 386 to 580 = 194 feet
4th Flight: 392 to 653 = 261 feet (Launched into thermal)
5th Flight: 382 to 631 = 249 feet (3 ballast slugs added)
6th Flight: 381 to 646 = 265 feet (Launched into thermal)

My average launch height over both days = 606 feet (1.23 times winch to turn-around distance)

So I have launch height multiples of between 1.2 and 1.34. Some of my earlier launch sessions were much lower. I'm going to just choose 1.25 to make life easy.

Opinion Time
If the ALES guys are launching to 150 meters (492 feet), they are clearly at a disadvantage with a 150 meter winch to turn-around pulley distance against winch proof moldies, especially in windy conditions. In light wind conditions, the ALES guys are usually going have an advantage with their lighter sailplanes, so a bit higher launch height from the winch guys doesn't bother me much (I said a bit higher). I think with this data, if I were going to put on a mixed launch contest, I'd probably go with 120 meters (393 feet) winch to turn-around. Multiply that by my 1.25 and that's 150 meters.

I hope this information is useful.

Jim

P.S. - We had 7 pilots at the contest. 3 winch and 4 ALES. An ALES pilot took first place on Saturday, and a winch guy took first on Sunday.
Last edited by GliderJim; Aug 26, 2019 at 01:22 PM.
Aug 26, 2019, 12:57 PM
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Man I really wish there were more glider guys in my area!

Though will say the last fun fly I went to in Bismarck, the guys there had never seen gliders like these. I was launching with a bungee, but explained the winch as well. Hopefully the bug will get to those guys and will be able to have a few "fun" contests.
Aug 26, 2019, 08:00 PM
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Regarding the ALES guys in our contest. I just remembered that per standard ALES practice, the clock started when the plane left the pilot's hand, not when the motor turned off. That means they were getting some free time during the climb, which certainly compensated for some of the launch height disparity. They were instructed to launch up and forwards towards the same general area as the winch guys. I think the best strategy in that case would be to milk your climb for as much of the 30 second run as possible. I don't know that anyone actually did that however.

So that's another variable to consider when trying to determine the fairest way to approach these contests.
Last edited by GliderJim; Aug 27, 2019 at 07:33 AM.
Aug 27, 2019, 06:45 AM
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Quote:
Originally Posted by GliderJim
Regarding the ALES guys in our contest. I just remembered that per standard ALES practice, the clock started when the plane left the pilots' hand, not when the motor turned off. That means they were getting some free time during the climb, which certainly compensated for some of the launch height disparity. They were instructed to launch up and forwards towards the same general area as the winch guys. I think the best strategy in that case would be to milk your climb for as much of the 30 second run as possible. I don't know that anyone actually did that however.

So that's another variable to consider when trying to determine the fairest way to approach these contests.
Thanks very much for this information Jim. Very helpful in determining fair winch line length for mixed launch contests. In our area mixed launch contests the time for motor in the nose models starts at motor off and does not include the 30 second or 150 meter climb. I'm surprised that Chicago did their timing with climb as part of the flight time. Usually in mixed launch the pilot calls motor off, determined by the climb stopping or sound, that starts the time, to replicate off launch line. In an ALES only contest we use standard AMA rules where the time starts as the model leaves the pilots hand.

Good work on maximizing your zoom!
Last edited by Barry Andersen; Aug 28, 2019 at 08:04 AM.
Aug 30, 2019, 07:13 PM
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I need to figure how to record and see the data from my spektrum controller.

Was out flying for 5 hours today! 73° average with skatterred puffy clouds, and winds under 5mph on the ground.

Was able to get quite a few launches of over 400'. Best was one up to 430' with a flight that lasted 45 minutes and some change. Average though was right at the 404' mark

Tried to have a buddy record a launch, but it was to quick for him to catch the entire thing.
Sep 01, 2019, 01:57 PM
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Another day, another set of launch data...

9-1-2019 - Red Zenith - Winds under 5 mph

1st Flight: 290 to 543 = 253 feet
2nd Flight: 320 to 550 = 230 feet
3rd Flight: 288 to 486 = 198 feet
4th Flight: 294 to 515 = 221 feet
5th Flight: 299 to 518 = 219 feet

One of these days I'm going to get all of my zooms over 200 feet.
Sep 01, 2019, 03:24 PM
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Have to figure out how you guys are getting the launch, and the zoom height!

I also have to get the zenith set up a bit better, as the plane still seems to "slide" around turns and tip stalls quite easily.

Would be fun if we were all closer, so we could have a "Zenith fun fly"


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