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Static towing ground based.

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Static towing ground based.

Postby Bill Cummings » Sun Oct 23, 2016 4:25 pm

Static towing preparation.
RGSA/Hawks,
Robin was over to my house a few days ago and we rigged Mike's and my Falcon 195' for static towing by means of a car or truck.
Not much was required as far as the glider was concerned.

We attached a keel anchor point for the tow bridle about ten inches ahead of the of the hang straps. On the nose of the glider we reattached a nose release cord and ring that for static towing will only be used for transporting the glider on the back of the ground based tow vehicle. That's all for the preparation needed for the glider.

Next I demonstrated for Robin how I tie weak links and then connect the weak link to the two string release at the apex of the Skyting bridle.
I prefer to fly with the bridle always attached to myself and the keel.

With my release at the bridle's apex I'm able to release with low chance of the towline snagging any part of the glider's rigging even if I would be gusted 90º left or right of the towing direction. I gave up using threaded bridles decades ago due to snagging captures upon releasing. I no longer have any trouble with threaded bridles ever since I stopped using them. They were extremely handy when they worked. (Less drag, looks better and all that nit picky drivel.) But, just under go a wrap and capture event one time upon releasing and you will easily fall out of love with the dreaded threaded bridle. :thumbdown:
We tried to break test a weak links but were not strong enough. I still have to test my weak link material. For static towing I prefer 222 lbs but nothing over 350 lbs breaking strength for payout winch towing. My rule is nothing over 1.6 of my all up weight.
Another must for me is to tow only while on constant radio transmit (TX).
Another must for me is to tow with no lower, of 5 mph wind speed for a, static, running, take off due to my age and ground altitude which is near 4,400' msl.
With the density altitude near Las Cruces, NM many times hovering around 5,000' msl I've had to set some minimum's for myself that were of no concern thirty years ago.
As mentioned elsewhere on the RGSA Club thread the Dona Ana County road grader must not be grading the tow road during tow operations. That is another minimum that is good advice for all pilot ages.
Of course towing is not just that simple. There are more lessons learned since I started towing early January 1978. I've only adopted a few new school lessons since towing procedures have, over the years, wandered away from from good lessons and procedures learned over time.
Just a few things that I've observed over time is what I call mission creep. Methods of towing changes that are thought to be improvements but have allowed bad stuff happening to creep back into towing that had been fixed years before. Improvements that contain words such as , aesthetics, less drag, more towline, adequate tow road, smaller towline, simplified bridle, are a few "Improvements," that have allowed back in bad things to rear their ugly heads once again.
So when something really scary happens that had never happened before; remember to put two and two together and ask yourself could our last, "improvement," have caused this (seemingly unrelated event.) to happen?
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Re: Static towing ground based. 10-27-16

Postby Bill Cummings » Tue Oct 25, 2016 9:37 pm

Hey Robin, Thursday, if the forecast holds, looks good for static towing out at exit 116 on I-10.
They are showing SE at 7 mph around 11am and on for a few hours.
The county plow should be done with the tow road.
How is you schedule for Thursday?
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Re: Static towing ground based.

Postby MattHayes » Thu Oct 27, 2016 12:12 am

Hey guys, long time no talk. Seems the female persuasion has had a strong hold on me. Well that is over now and it's time to get back to my true love and the one that never lets me down( no pun intended). I have a job interview on Thursday( today) at 10:00 am, but it shouldn't take very long and I'd be interested in helping out on the tow operation. I have a new phone number, a Ruidoso number, 575-808-0952 so give me a ring before 10:00 and let me know if my help or company is desired. Hope to get back in the air asap depending on my work schedule( if I get the job). Good to see the activity on YouTube, thanks Bill for posting videos!
~Matt Hayes~
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Re: Static towing ground based. Oct 27, 2016

Postby Bill Cummings » Thu Oct 27, 2016 7:39 am

Matt and Robin checked in by phone and we should be NW of exit 116 off Interstate 10 around 11:30am today Oct. 27, 2016. :D
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Re: Static towing ground based. 10-27-16

Postby Bill Cummings » Thu Oct 27, 2016 9:33 pm

Matt's interview must have gone real well since he didn't find us.
Robin served my up four times and the fourth was a charm. Thermal to 3,600' agl.
I got chased out of a thermal by a hawk (Yeah -- right --Bill) otherwise I would have
had a longer flight. (No-- really-- check out the video!)
I put a longer explanation of the flying on the YouTube comments below the video.
https://youtu.be/ZmsiOr5vOrs

Bill on final Exit 116 10-27-16 photo by Robin Hastings.JPG
Bill on final Exit 116 10-27-16 photo by Robin Hastings.JPG (11.04 KiB) Viewed 808 times

Going upright for landing, Exit 116, 10-27-16.JPG
Going upright for landing, Exit 116, 10-27-16.JPG (19.68 KiB) Viewed 808 times

Touch down with a few wrinkles..JPG
Touch down with a few wrinkles..JPG (41.87 KiB) Viewed 808 times

Grandpa Bill.JPG
Grandpa Bill.JPG (89.49 KiB) Viewed 808 times
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Re: Static towing ground based.

Postby RobinHastings » Fri Oct 28, 2016 8:17 am

It was a darned good flight, Bill. I'm glad I could help. (Especially since you drove for me at Dry Canyon on Monday!)
-Robin
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Re: Static towing ground based.

Postby MattHayes » Fri Oct 28, 2016 8:12 pm

Hey guys, sorry I missed out on the day. I had a second interview yesterday and started work today. I left you a voice mail Bill. I am now a small engine mechanic for Sun Valley True Value hardware. I will be working weekends so my days off will be during the week. Hope to get out with y'all on some of that towing action soon. You made it look all too easy Bill! I will be in contact when I know what my schedule will be like.
~Matt Hayes~
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Re: Static towing ground based.

Postby Bill Cummings » Thu Nov 03, 2016 10:16 am

Congrat's on the new job Matt.
I just bought 1,000' of new towline ($108.32) to add to 600' of existing stuff. I'm going to retire 1,000' of twisted 1/4" Poly-Pro.
I was reviewing my procedures for any, "Mission Creep," and found that I had allowed "Mission Creep."
First off, since while static towing and dragging the towline on the dirt roads, I went without the expensive small towline and
went with the cheaper Poly-Pro. They carry it locally and one doesn't need to special order and wait for it to arrive.
Over time 3/16" Poly.- wore out too fast so I went with 1/4".
The 3/16" had the correct amount of stretch for a length of 1,600' of towline.
But 1,600' of 1/4" Poly.- lacked the proper stretch needed for a running foot launched static tow.
What worked was 1,000' of 1/4" Poly.- with 600' of 1/4" Nylon. That yields the correct amount of stretch and lasts several years.
Nylon stretches 10 to 15% while under tension.
Now back to the, "Mission Creep." ---
Long ago twisted rope revealed some unwinding while under tension.
This unwinding twisted braid type of towline would twist up the "V" tow bridle. (Skyting Bridle.)
The top tow bridle rope to the keel tube and the bottom ropes to the pilot would end up with several twists which placed the release cord
in a captured situation making it difficult to impossible to release. (I have an in flight procedure for this situation.)
How the twisted rope crept back into my operation I have no memory of. I'm betting money had something to do with it. :oops:
A lot of money must have been saved at the time because splicing twisted braid is WAY more unhandy than hollow braid.
As soon as someone is free to assist me I'll have to get the old retired rope off of the reel and put the new hollow braid towline on.
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Re: Static towing ground based.

Postby RobinHastings » Thu Nov 03, 2016 6:50 pm

Tomorrow (Friday) is one where I don't teach, so I can come over to give you a hand with the rope. Let me know what your schedule is, Bill.
-Robin
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Re: Static towing ground based.

Postby Bill Cummings » Thu Nov 03, 2016 9:01 pm

Robin, I'll give you a call as soon as I get rolling tomorrow. Thanks! :salute:
EDIT: By the way I modified the two string release to prevent inadvertent rigging.
I also worked on the car's Johnson Inline Release to require less force to release the towline.
More can be done if there is a need.
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