Aerotow ropes: short or long, breakable or unbreakable?

Previous posters have written
- "...plus a tiny bit extra due to the climb vector", and
- "Since the glider is being towed uphill, the load is slightly more."

Actually the load due to being pulled uphill is typically 10% of the
weight of the glider (thinking of a typical climb of 6kts at 60kts
airspeed).
This is significantly larger than the drag component, which is in the
range 2.5% to 2% for a decent performance glider (say L/D of 40
to 50), and maybe 3.5% for an old 2-seater (L/D of 28).

Pedantry?

I guess I used kinda vague terms like "tiny bit", and "slightly".

You did the math and put some actual numbers on it. ( Large compared to the
drag...small compared to the rope strength)

So if we say the tension on the rope is smooth tow is 12% ~ 15% of the
glider's weight, and the rope strength is 80% to 200% of the glider's
weight, we have a pretty good safety factor there.

Yet a rope that should break if things get "hairy"..

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At 15:24 13 November 2013, James Metcalfe wrote:
Previous posters have written
- "...plus a tiny bit extra due to the climb vector", and
- "Since the glider is being towed uphill, the load is slightly more."

Actually the load due to being pulled uphill is typically 10% of the
weight of the glider (thinking of a typical climb of 6kts at 60kts
airspeed).
This is significantly larger than the drag component, which is in the
range 2.5% to 2% for a decent performance glider (say L/D of 40
to 50), and maybe 3.5% for an old 2-seater (L/D of 28).

Pedantry?