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Static towing ground based.

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Re: Static towing ground based.

Postby SamKellner » Thu Nov 23, 2017 1:49 pm

Any more thoughts on the tow in clinic?
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Re: Static towing ground based.

Postby Bill Cummings » Fri Nov 24, 2017 9:40 pm

Sam,
I don't instruct but have no problem with showing people how I tow up with a static towline. I also have been known to offer up explanations
about why I do certain things the way I do so that anyone planning on trying to copy my procedures doesn't blow past an important and easily missed safety concern. Having learned since 1978 many of the things that can go wrong while one is towing I tend to avoid stuff which to an onlooker may lead them to believe that towing is almost boringly easy to do.
Some of the big names in towing have offered up tabloid phrases about aspects of towing that can easily lead people off of the well beaten safety trail.
I've watched the chain of events often lead people to remedies that work like time travel. Taking them back to a situation that had spelled disaster decades ago and here they are learning anew the really hard and already proven way.
Example: The lawn mower broke, the grass grew tall on the runway, the launch dolly wheels were a little under inflated, and there was a weaklink break during the tow operation. Simple solution = increase the strength of the weaklink!
Next more tow tension for the first time caused the tow bridle to stretch excessively and when the weaklink broke the release snapped back and injured the pilot. Who would have ever thought that would happen? (For sure some old tow pilots like you and me!)
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Re: Static towing ground based.

Postby SamKellner » Sat Nov 25, 2017 9:00 am

Bill, Hawks,

That all sounds good to me. We are lucky to have a tow veteran like yourself, in our ranks. :salute:

Personally, I have never had the opportunity to try static towing ground based. Not enough suitable roads in this area.

The low and slow scooter towing works great for beginner pilots and experienced pilots who have never tried tow launch methods.

The equipment I use is standard and widely accepted. Also the agenda.

It would be great to have any kind of Hawks get-together. At a site where u$hPa was not a factor.

:wave:
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Re: Static towing ground based.

Postby Bill Cummings » Sun Nov 26, 2017 2:06 pm

SamKellner wrote:Bill, Hawks,

That all sounds good to me. We are lucky to have a tow veteran like yourself, in our ranks. :salute:

Personally, I have never had the opportunity to try static towing ground based. Not enough suitable roads in this area.

The low and slow scooter towing works great for beginner pilots and experienced pilots who have never tried tow launch methods.

The equipment I use is standard and widely accepted. Also the agenda.

It would be great to have any kind of Hawks get-together. At a site where u$hPa was not a factor.

:wave:

Sam, I watched scooter towing done by Ed Bennett when he lived in Alamogordo, NM. Until that time I had always thought that towing should only be taught to at least H3 rated pilots. It changed my thinking and I now know that it can be used to safely teach H1 to tow.
However, when I hooked up to his scooter/pulley, tow operation I chose not to use his bridle that hooked up to the pilots chest area and towed through the control frames triangle.
I hooked up with my old Skyting Bridle that had the weaklink and release out ahead of all the gliders rigging.
I will say that the chest mount area attachment can be done safely with the right horsepower scooter, wind conditions, and an operators that knows what their doing.
The reason I chose the Skyting Bridle is many fold. It allows me to handle too much HP, too strong of wind conditions, and an operators that don't yet know what their doing.
Also and although a student may not yet have to activate a release during the beginning of their tow lesson, I'm past that point and can release if I get gusted 90º left or right of the towline. Some chest releases can have the released towline wrap and capture the left or right nosewire if the glider is gusted 90º to the towline. This is why I prefer to have the release out at the apex of the Skyting Bridle. (Also one of several reasons why I'm not as fond of aerotowing.)
The keel attachment of the Skyting Bridle gives me more pitch authority and protection from being, "locked out over the top."
Too much line tension due to too much horsepower, wind gradient, or an operator that wants your wife, can have a pilot climbing too fast.
My Sport 2 has enough energy retention to allow me to handle a 350 pound weaklink break without showing me a hammer head stall. It would be too strong to use with the 195 sq' Falcon which would show me a hammer head stall due to less energy retention and the greater pitch positive characteristic at its top end airspeed.
We also have a shortage of tow roads due mostly to the creosote bushes, prickly pear cactus, and a host of other desert towline grabbers. Close to Las Cruces we have roads that handle N-S, NW-SE, but nothing SW which is the prevailing wind direction.
That makes it tough to schedule a towing get together in our area.
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Re: Static towing ground based.

Postby Bob Kuczewski » Sun Nov 26, 2017 2:59 pm

Bill Cummings wrote:Too much line tension due to too much horsepower, wind gradient, or an operator that wants your wife, ...

:srofl: :srofl: :srofl: :srofl: :srofl: :srofl: :srofl: :srofl: :srofl: :srofl:

I know you hide those in your posts to see if we're really reading everything you write.   ;)      Did I pass?

Bill Cummings wrote:That makes it tough to schedule a towing get together in our area.

I really like Sam's idea of a towing get together in Las Cruces. Watching your repeated static tows on video gave me some courage (emphasis on some).
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Re: Static towing ground based.

Postby Bill Cummings » Tue Aug 07, 2018 8:56 pm

August 7, 2018
All the weather models, on Monday night, were in agreement. Tuesday It would be southeast wind at 8 to 10 mph.
Tuesday morning some of the models were staggering in different directions at different speeds.
I'm not sure what kind of models we're talking about here but they must have been paid with beer or it was their
first time wearing high heels.

Like the suckers that we are Robin and I headed for the Exit 116, SE - NW, Tow Road only to find out none of the more reliable models bothered to showed up.

The light and variable winds were mostly south so we decided our best course of action was to revert to our hang one (H1) way of thinking and start chasing the wind.

Half way to the 3 miles distant north - south tow road we noticed it was blowing out of the southeast.
While still caught up in H1 mode we raced back to the SE - NW Tow Road only to find it light and variable, mostly cross, and sometimes out of the southwest.

As airtime deprivation panic took hold of me going to Mag Rim or even the Little Florida Mts dashed through the aggravated conversation. (It was hopeless.)

With both of us back in hang four (H4) mode we started for Las Cruces.

We decided to check out if the road to Volcanic Peak had dried up and swung over to the south. It was dry but the rain
had really carried away parts of the road so that a car would now have a tough time getting to the launch. Vehicles with some clearance are needed now. The road up to launch took the worst hit. Robin braved the rattle snakes and cleaned out the culverts on the road up. We also moved rocks and made damns in an effort to save the road from the coming rain.
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Re: Static towing ground based.

Postby Bill Cummings » Fri Apr 24, 2020 3:52 pm

RGSA Hawks and Drivers,
A while back I had someone comment on one of my YouTube videos that the crosswind stake I was using for take off was not that easy to see.
I'll put the link where I had the comment but like was said it doesn't show much even though it's being used for static car towing.
(Come back to the link after reading this post if you like.)
https://www.youtube.com/watch?v=E6IFmX3t2vg
In my drawing below you will see an east/west tow road that has a left crosswind. This is when I pound in a Crosswind Stake to allow
the running take off into the wind. As I leave the ground with the hang glider the towline will lift up and come clear of the crosswind
stake.
To make the stake I had the hardware store put threads on each end of a two foot long pipe that was 1/2" diameter.
Next I cut the pipe in half.
Next I threaded the two ends into a pipe coupling. The next step was to place a big enough washer to fit onto the pipe but stop
at the coupling. I would pound the stake into the ground so that the coupling was in the ground with only the end of the coupling
flush with the surface. The big washer was resting on the ground and the end of the coupling.
Next a bigger pipe was placed over the one foot pipe half that was standing vertically above the ground.
crosswind stake.JPG
crosswind stake.JPG (16.73 KiB) Viewed 654 times

Picture of Crosswind Stake..JPG
Picture of Crosswind Stake..JPG (52.84 KiB) Viewed 654 times
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Re: Static towing ground based.

Postby Bob Kuczewski » Sat Apr 25, 2020 12:42 am

That's pretty clever Bill. When I first saw your diagram, I was concerned about the friction of the rope around the stake. Then I looked closer and saw your vertical roller bearing.
Brilliant. :idea:

I do have one question. When the rope rolls off the stake, do you notice the transition in either tension or direction?
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Re: Static towing ground based.

Postby Bill Cummings » Sat Apr 25, 2020 3:36 pm

Bob Kuczewski wrote:That's pretty clever Bill. When I first saw your diagram, I was concerned about the friction of the rope around the stake. Then I looked closer and saw your vertical roller bearing.
Brilliant. :idea:

I do have one question. When the rope rolls off the stake, do you notice the transition in either tension or direction?

Yes to both questions Bob.
crosswind stake.JPG
crosswind stake.JPG (16.73 KiB) Viewed 635 times

There have been times when I used a Crosswind Stake that had the towline doing a 90° angle at the stake.
For pilots starting out using a Crosswind Stake it would be prudent learning with only slight cross winds.
A tow pilot should already know that while towing the best place to be is downwind of the tow vehicle in the sweet spot.
The longer the towline the broader is the sweet spot that the pilot can safely operate (left and right) of the tow vehicle.
Shorter towlines also narrow the sweet spot.
Higher towline tension narrows the sweet spot. The lower the towline tension the sweet spot is wider left and right.
Using the Crosswind Stake narrows the sweet spot that is to the right of the stake in the picture shown above.
In this example the pilot should release if his glider is moving toward the right of the stake.
If the glider is heading to the right of the stake a lockout can occur quickly.
The pilot is in good shape if the glider is moving toward the stake or even to the left side of the stake.
As the glider lifts the towline above the stake the tension will drop a lot and now you are no longer in the sweet spot of the
Crosswind Stake but actually to the left side of the sweet spot of the tow vehicle. During this moment of reduced tension
the pilot needs to point the glider toward the tow vehicle and allow the cross wind to drift the glider to the down wind side of
the tow road. The sweet spot is not centered over the road but down wind of the road and the tow vehicle.
The pilot will have to radio to the tow vehicle to speed up since the glider is no longer headed straight into the wind
after the towline clears the Crosswind Stake. Also once the towline clears the stake the sweet spot of the tow operation
becomes instantly larger and even more so due to the drop in towline tension.
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Re: Static towing ground based.

Postby Bill Cummings » Thu May 21, 2020 7:26 pm

RGSA/Hawks and drivers,
After learning to boat tow I then moved to static towing on dirt roads using my car.
The fancy schmancy new age towline was so expensive that I instead used 3/16" Polypropylene.
This rope is used for water sports like water skiing. It is light and floats on water and
is not expensive. The twisted rope tends to unwind when under tension so I used the
hollow diamond braid. It will not twist or unwind when under tension. It is also easy
to splice without a using a knot which makes it last longer if it is drug on a dirt road.
The smooth splice is done normally with a plastic Fid that uses the Chinese finger trap
or handcuff principle to maintain the splice. Since the Fid is so mindless and stupid it
wanders off and gets itself lost nearly 100% of the time. Your results may vary.
In the field a line break can be spliced back together by melting each end of the break
with a cigarette lighter and then with a piece of paper twist the melted end into a smooth
and blunt end. After much break testing of splices between two cars we found out that
a splice that has one foot and six inches for each leg of the splice will work without
any trouble. One foot for each actual leg of the splice with six inches more left to taper down
to keep the splice from failing.
If one doesn't feed the hard melted end back outside of the rope to be cut off that is
exactly where the rope will break the next time. Even cutting off the hard melted end
isn't enough. The last six inches have to be unwoven and cut to make a taper inside the
towline on each end of the splice.
In the link below a locking knot is used but will not be needed if the splice is one foot
and six inches for each end of the splice. This fellow is very meticulous about the
tapering of each of the ends of the splice that will be inside the towline. However
six inches of taper hasn't failed me in more than 40 years of towing hang gliders.
The video shows how to make an eye splice and not an in line splice but this video
is really to help understand what is being talked about and the importance of tapering
a splice to maintain the strength of the tow line.
Go to 11:53 to start the tapering part that is so important to maintain the rope strength.
The first part does not apply to the in line splice that I am talking about.
https://youtu.be/UpkqJ4GRfSg
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