In article ,
Bill Wallace wrote:
The only time I have ever seen a tow rope break is during an
intentional rope break manuver.

Same here. The only time I've ever seen two rope breaks was during
our two intentional rope break manuevers.

Eastern Sierra air since 1968, as a glider pilot, tow pilot, air
ambulance driver (rotorcraft). I have thousands of hours flying the
east side in all kinds of conditions (many hundreds of flights in wave
and rotor conditions). Mark, something seems odd about your
descriptions and experiences. Are you getting professional assistance?
Please do not take my post as a slight, as it is not meant to be
degrading.

I was very satisfied with my instructor and the instruction we did.
I certainly feel confident I know the difference between textbook
correct and incorrect slack line procedures
(having practiced both intentionally).
I'm also confident that the rope will not break during normal,
and even fairly rough tows with standard technique.
I'm equally confident it will break cleanly if stressed enough
(and will do so without damage to the towplane or glider).
I'm convinced to practice such things over
desolate areas, and I'm convinced the 2-33 will back release
if the rope breaks with 100+ feet of line and
drags back behind the glider (although I've never had the
experience like Brian's back release without a rope break).
Overall I'm quite satisfied with my "professional assistance."

Your question also prompted me to to call back my friend who
had two rope breaks flying into wave in the Sierras. He's
also a pilot examiner for power and a commercial glider pilot
and gave me some more detail, including exact CFIG name and
dates and FBO. I called the FBO (which uses high tow through
wave, by the way), and got some additional confirming detail.
I'm tempted to share what I learned, but perhaps will wait
until I'm able to get an even fuller story and permission
to use names in person from the CFIG up in the Sierras.

The general gist is that my experience seemed not uncommon.
Ropes break where they are worn, which is not always
at the weak leak. Imperfect technique by pilot or
tow pilot may break a rope. It's harder in rotor
because so much is going on.

Bill, your response is relieving, because it suggests you are
an experienced tow and glider pilot in rotor, and that this
experience has made rope breaks non-existent for you.
It's nice to hear that with experience, rope breaks are
not inevitable. Perhaps you could also please share with
us your techniques for towing/being towed through rotor?
To fix slack line, do you yaw? Do you go high/low?
Do you ever use spoilers? Have you tried a low tow?
Do you tow through rotor, or around, over and on top of
the wave? Have you ever released rather than watch
an apparently inevitable rope break?

Sharing your personal experiences would be perhaps be
more enlightening than any of my further comments...
Pray tell...