Is there a nose hook modification for a standard cirrus

"True" nose hook is higher and more in line with the center of mass, thus reducing the pitching force when rope tension is really high. This helps with kiting to a degree. It is possible to yank hard enough that this pitching force can exceed the ability of the horizontal tail to overcome, especially at high weight and aft CG. Dick Johnson did an article about this in late '86 or early '87.
Also provides some straightening effect in yaw obviously.
FWIW
UH

Per UH's note, see Dick Johnson's Tail "Stall While Towing", Soaring mag, May 1987. For those who aren't aware, Dick's article arose from discussions I had with him and (independently) Air Force test pilot Jim Payne following Robert Robertson's fatal towing accident in 1986. I had spoken to each about my suspicion that there was more going on in that tragic accident than just all-up weight, CG, or tow speed. Both experts reached the same conclusion: i.e., in some circumstances, a robust tow plane, high/ballasted glider weight, CG towhook, and/or slower tow speed could possibly make the tail susceptible to stalling, with disastrous consequences.

To this analysis I offered another twist, with not much agreement in this group: if the glider pilot were hanging on, nose high, with the stick in his/her lap desperating hoping for the tow speed to increase and then decided to give up and release, then pushing the stick over might itself trigger tail stall because of the near instantaneous increase in effective elevator angle of attack resulting from the up-to-down change in elevator deflection.

Years ago, my LS-3 popped the nose up sharply for a moment rolling out behind a powerful towplane just as I lowered the flaps to lift off and we flew out from behind a row of hangars that had sheltered us from the wind. In that case, a quick full-forward-stick motion reversed the incipient kiting (I could never recall whether I moved the flaps back to zero, but that would have helped) and my heart rate returned to normal.

As far as directional control, I've been flying gliders with CG hooks since 1978 (LS-3, ASW 24). I never thought having a nose hook was a big deal until I rolled off the runway last summer in Nephi after my wing dropped early with full water ballast. I'm not sure if a nose hook would have provided enough steering force to prevent hitting a landing light. But I could have avoided doing so simply by releasing, as I've done several times before (and once since!).

We do mostly aerotow here in the U.S. A CG hook isn't unsafe. But if I had the choice, I'd take a nose hook just because of the modest benefit.

Chip Bearden