Tow line recovery

[lenb]

The typical scenario around my parts is plain old dumb thumbs. ( or finger)
We tow so much that its inevitable that some point over the weekend a tug pilot will accidentally flip the release switch on the transmitter. I've done it a bunch of times over the years thinking I was hitting the flap or something like that. Usually when your tired.
So its not about any one cause, and there are so many tow release setups that its impossible to police them all. We had a couple no release situations so fare this week in Cumberland

for a release, go with around 200

[kjkavaney]

At risk of offending someone, most of our tow release failures have been with smaller gliders and with people new to Aero Tow....we have tried really hard to not "out-snob" future potential big scale aero tow pilots who are presently coming to our event with small, foamie, 3 meter sailplanes to see if they are really wanting to go down this DARK path...It IS a BIG STEP for a lot of people.$$$$
We are trying to grow our fleet of big scale sailplanes...doing our best to be "inclusive"

Few, if any of the more seasoned guys do NOT present with this "problem"

We have ALL been beginners at one time, and we are trying to incorporate as many NEW people to this format as possible...
Perhaps in other events other than ours , the whole tracking device would be not needed. NOted though...most people flying at Horizon Hobby Aero Tow this year were all are fairly experienced glider pilots, yet 6 tow lines were lost and NEVER recovered...in spite of hours looking for them by multiple people...up to 90 minutes in a bean field with zero recovery.

Noise has often been the demise of flying fields, but if we piss off the farmer in our "fly over" areas with tow lines jamming up their farm equipment, we equally risk the loss of aero tow flying at a given field..

[BryanB]

Yes, some very good points especially about those just getting started. I do think impressing on people regardless of where they are in the hobby that the tow release isn’t just an after thought servo but needs to be of as high or higher quality than a primary flight control.
ARUP’s suggestion of asking the tow plane to throttle back a bit just before release may help solve some of this.

It would be informative to find about how much oz.in. servo is actually required for a given weight of strain on a typical loop and pin release and if the tow loop has to make a bend out of the fuselage if that makes much difference.

[68mustang]

Would something like a pull simulation before a first tow using a fish scale help to check out a new release mechanism?

[kjkavaney]

I think that is an excellent idea, I am sure our program guys will be reading this thread on here..

[tree2tree]

The "dropped tow-lines" that I have witnessed - including a couple I dropped were the phat-phinger type that Lenb mentioned above. Something like the release switch was flipped when the pilot meant to flip the flap switch. This is a great forum thread as it has made us brainstorm the issue. Here's an idea to kick around (sketch attached): Tie a safety line to the main tow-line, just down from the tug release. The other end of the safety line is firmly attached to a strip of Velcro (loop surface). The opposite Velcro (hook surface) is adhered to the fuselage.

In an emergency release situation, the tug pilot releases as normal; the Velcro patch is small enough to let go under the load of the glider.

However after a normal glider release, if the tug pilot mistakenly hits the release switch, the Velcro patch is strong enough to hold onto the tow-line.

It will take experimentation to get the right Velcro patch size.

Thoughts?

[kjkavaney]

cool idea...will spread the word !!!

[Swiss1]

A good idea, but I think the initial pull of the line will require a large patch of Velcro to keep the line with the plane, and when the situation happens with a glider on the end of the line the pull of a large piece of Velcro could rip the covering of the tow plane if its not composite! Just my 2 cents

Jeremy
SCCAAA TT TN

[ARUP]

Jeremy- If the tow pilot accidentally releases then the line will come 'unstuck' from the hook and loop patch. If that occurs then the sailplane pilot should NOT release and should only attempt to drop the line over the field or just land with it. As Noel has stated, some experimentation will be required to see how large a patch is required to keep the tow line from falling away when it doesn't have a sailplane attached to the other end.

There is always a possibility that the patch size needed to retain the tow line may pull covering off the tow plane.

[edfmaniac]

A complete system just came up for sale on one of the freeflight Facebook pages. It's being offered by one of the kit manufacturers if you don't have Facebook so you can contact them through the website I would imagine.

FOR SALE - $350 SHIPPED*

Older Walston Retrieval System from Stu Weckerly's estate. Includes a 3-channel receiver and a single 3-gram transmitter.

Includes fresh AAA batteries (8 total) and OLD #317 transmitter batteries (suitable for TESTING ONLY). Also includes carrying cases (as shown) and instructions.

This unit works and served Stu well. It still works - tested yesterday. The clip on the receiver case is broken and repaired, but should be replaced.

This is a great price - priced to sell. SELLING FOR THE CLOUDBUSTERS CLUB. * - NOTE: free shipping in the US only. Payment via PayPal preferred.


https://www.facebook.com/VolareProdu...37231176391963

https://volareproducts.com/BUY/