Originally Posted by bbbp

It sounds like you were really puffing when pulling for launch, like football practice pulling a sled with 2 linebackers on it! Are you winded after launch?

BP

Hi BP,

It's not even close to football. If you heard any puffing it was probably the camera boy who had run out to his post to video the launch.
You may have also heard the sound of the braided line touching the pulley guides.
Yes - it will take 10-15 seconds of exertion, but it's more like taking a flight of stairs than football practice.

Tim

If it was too much effort, you could always change the pully ratio and have a longer distance pull with less effort.

Below is some more recorded data from a OneWinch launch over the weekend. I decided to hang on the line after the initial rotation and fly back and forth. The idea was to just maintain tension and let the wind do the work. This is the area in the circle. While I wasn't gaining a lot of altitude here, I was letting out the line a little, giving me more to work with for a final pull and ~100 foot zoom (at the arrow). The plane was on the line about a minute. This was easily the highest launch of the day. Wind was 10 mph at the most. I tried this again later, but the wind had died off and the zigzags didn't accomplish anything. This would have been easier with a releasable tow hook.

Tim

On the same day I launched a friend's moldie - a well used old Artemis, not a light plane. He launched with a flat wing to reduce drag on the way up. It worked great.

Tim

very interesting Tim!

I wonder if there could be another market for the OneWinch.

Interesting idea. Never thought of launching a kite with a winch type device but it makes a lot of sense.

I'm starting to wonder if I should buy a one winch instead of a high start?If I buy a comp 2 meter hose monster I can only use half of it at my home field,If I can launch to 400 ft.I'll be in a thermal around here. So I am reading this tread all the time now ,thanks for your continued research

I hope to get a LOT of time on the Onewinch tomorrow. I have asked the club to bring planes and I hope someone brings a video camera. We gonna use and abuse this baby to see what it can do.

I will have my Thermal Dancer (3.2m bagged wing) out there again but I will be launching it by myself and I will play with various launch mixes.

I am also bringing my 3.4M Graphite which is the hardest pulling, most winch stalling plane I have. I have yet to see noticeable flex in the Graphite's wings when I stand on the pedal of an ESL winch. I will likewise be playing with mixes on this one.

I have a 2 day ESL contest next weekend, so the Supra, my main plane, stays in the hanger. These are my back-up contest planes.


I hope to have a detailed report for you, some photos, and maybe some video too. And I plan to bring it to Virginia to the ESL contest at CASA. I have been requested to bring it. The contest pilots are dying to give it a try. When I had it out at the Boston ESL contest I had an audience.

Cool! Can't wait for your extensive report aeajr.

Hi Ed,

I would really like to hear your thoughts too. I have been contemplating getting one of these for my Rochester Soaring group. The idea of having one devise that can launch anything from small 2M planes up to a 3M ship is very appealing.

Wayne

Excellent. Sounds like you guys are going to have a great time. Look forward to the feedback.
Glad the hurricane is through and you're back to flying.

Tim

If current forecast holds, we should ahve about 5 mph wind in the morning and about 11 in afternoon so we can get a feel over a variety of wind conditions. I already tried it in nearly calm conditions and it worked well.


Tim,

I think I asked this, but if I wanted to add more line for higher launches where and how would you recommend I add it. I can't find where you may have answered this.

I would expect that, which a bit of a breeze I should be able to add some line. Or, would you recommend against this. Counterproductive?

Your thoughts?

aeajr,

It's easy to add line. Use the knots recommended in the instructions and you will get strong connections with low profiles. Be sure to preserve or recreate the kevlar sleeving at the close end of the braided line. This loop takes the most abuse during setup and it needs to remain overbuilt.

Avoid a configuration that pulls knots through pulleys during launch, just to keep things as smooth as possible. Properly formed knots pass through the pulleys without notice, but repeated crosswind launches could wear a knot passing through the turnaround pulley.

You can add line to either end. Adding mono gets you more stretch and zoom capability.

Adding line will increase launch heights whether or not there is wind. But with wind you may not have to increase your pull distance much at all.

Tim

FIELD REPORT - I will follow with more, with photos and perhaps some video, if it came out.

We spent 8 hours at the field yesterday. About 5 of that was spent with the Onewinch.

Bottom Line - winner! This thing works as advertised and I like it. Note that I own a FLS winch and two hi-starts so I have a full range of tools for comparison. And I am a member of a glider club that has 4 club winches. Some members have sport winches and we have a variety of hi-starts. We launch gliders by various methods all the time.


What it is not - It is not a replacement for a Ford Long Shaft based competition winch. The Onewinch simply can not generate the 200+ pounds plus of pull that a FLS winch can generate. And it is not advertised as a replacement for a FLS winch.

What it is - A clear alternative to a hi-start and maybe an electric sport winch.

What I learned.

Conditions - Clear, 78 degrees. Breeze was about 3-5 mph in the morning going to about 10 in the afternoon.

* The Onewinch is easy to use
* Just like alternative launch methods, you have to work on your technique
* Proper tuning of the plane to the launch method will improve results.
* The average guy can easily manage the pull and the coordination
* I was launching in fairly rapid succession and I did not feel overly fatigued
* More fatigue was probably from the walk to get the chute than the launch
* There is a lot less walking than when using a hi-start
* You can use it on a shorter field than a hi-start and get a full launch
* shortening the length is very easy if you don't have room for the full set of line
* You get similar power to a hi-start but you can control/sustain it throughout the launch
* Hook position is the critical factor to success - more on this


Three planes were used. A Radian that has had the motor removed and a hook attached. Actually several of our members have done this. Works quite well. This amazing little glider has been launched with hi-starts and with a winch, so putting it up on the Onewinch was a valid test. Net results were very good.

My Thermal Dancer, which I have launched on the Onewinch before, launches great on the Onewinch. My techique is getting better and I am starting to get a good feel for when and how to use my launch mixes.

My Graphtie, a 3.4M built up competition plane, had problems. The problems were caused by the hook position, not the launch method.

What I learned is that it is not the plane that is the difference, it is the set-up of the plane. This is a critical factor to understanding where and how the Onewinch fits into the range of launch options we have for string launched gliders.

The Graphite is set-up for all out competition climb on a FLS competition winch. When I launch it I strain the winch to tension the line and when I throw it it goes almost straight up on a full pedal launch. I have the hook set so the plane rotates hard and immediately. I have broken 200 pound test line with the Graphite. I can not duplicate this launch power with the Onewinch so the Graphite's set-up is not optimum. If I moved the hook forward a bit it would launch much better on the OneWinch.

The Onewinch can not generate the kind of pull I get from the FLS winch. As a result the Graphite, in the current configuraion, tends to stall on launch. I have to really run back fast with the One Winch to try and generate enough speed and tension to keep it from stalling as it tries to climb straight up. After 3 attempts I finally got a full launch but if I were to use the OneWinch as my main launcher for the Graphite I would move the hook forward a bit so it would take a less agressive angle and could pick up speed more easily.

Note that I have the same issue with the Graphtie and my Supra when launching on my 3M hi-start. My hi-start is strong, providing 24 pounds of pull at launch and both of these planes tend to stall on launch with that hi-start unless I have a strong breeze to help. It is not the weight of the Graphtie (60 ounces) or the Supra (65 ounces) it is the hook position.

The Thermal Dancer wings are not as strong as the Graphite's so I have the hook placed less aggressively, a little more forward. When I launch on the FLS winch I don't tension up as much and I tap it up the line. The hook position on the Thermal Dancer is much closer to optimum for the Onewinch. It gains speed easily and climbs nicely.


Conclusion: The setting of the tow hook is a critical factor in the success of launching with the Onewinch. If your plane is set up to launch well off your hi-stat it will launch well off the Onewinch. If you have it set up for aggressive launch on a FLS winch, it is going to be tough to get it to launch well with that hook position. Move it forward a bit and it will launch well.

Note that all launches were done with no launch mix engaged at initial launch. More on mixes later.

But it was a good day and my friends seemed to like the Onewinch. I hope to get some of their comments too.