Well, I'm not a mechanical engineer, but...

It seems to me you should be more interested in the breaking strength of
the highest weak link you could imagine using and then add something for
the wife and kids.Â* If you design your tow plane mount to a 300 pound
limit, you'll likely be leaving the mount, release, and rope behind the
first time a glider pilot gets sloppy and gives you more than a gentle tug.

On 10/15/2018 12:33 PM, Retting wrote:
Well, I said ‘during tow’ thinking that would cover beginning to end. I need to determine the attachment strength for a tow hook on a towplane.
What might rope tension be from initial roll in grass (thinking start will be highest). I thought maybe testing was done years back and a chart or data existed.
Years ago back when I was teaching at Schweizer, the topic came up and less than 300#, towing the 2-32, 3 adults, behind a 180 Supercub was agreed by Paul and a couple of engineer types. I took it as gospel, but have wondered over the years how close they were.
Now I am really curious.
My previous thread got off track into formulas, winch launching, and pitch angles.
The info provided so far seems encouraging. I thought it might be higher.

R

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Dan, 5J