Thanks again, Steve, I appreciate your ideas. A few comments:

1) The people experiencing this problem at my club are flying a LS-8, a V2x, an ASW-27 and a Duo, all behind a Pawnee with tow ropes no shorter than 200 feet. Our G-103’s don’t seem to have the problem (longer wings? But then why the problem with the Duo?)

2) Our tow pilots are aware of the problem, and they’re working with us. We’re going to explicitly remind them of the potential for the problem each time they start towing us.

3) Next time I fly I’ll ask the Pawnee pilot (at altitude) to slow down and I’ll go into low tow to see if it helps. Since I fly an LS-8 which is reported particularly susceptible to the problem, if that works out for me it should help others (particularly at a site where the tow plane doesn’t have a radio). It won’t be rigorous, but a positive report might be of some use.

-John, Q3

On Wednesday, November 6, 2013 2:29:47 PM UTC-5, Steve Leonard wrote:
Yep, pretty much. And since the wake moves around, you are never centered in it.

Faster gets you lower AOA. Deck angle also goes down a bit more due to reduced downwash angle from the towplane wake. Below the wake, the air will be also getting pushed down, similar to how above the wake, it will be getting pulled down. So if you do get below the wake when being towed slow, you are still going to feel precariously nose high. And sometimes, pilot "gain" is heightened to the point where the pilot can drive what seems to be an instability (PIO). Us humans are good at being able to accidentally couple with a natural frequency and drive it. I know I have done it.

I do think it could be a worhtwhile program for someone to study. I do think that a longer rope will get you further away from downwash influences, if you are flying high tow. If you are flying low tow, the longer rope will likely mean that you have to go well below the altitude of the towplane to get below the wake. And you will still end up close to the wake and downwash, so a longer rope for low tow would likely provide no benefit.

It is also possible that the if glider being pulled too slowly by the short wing towplane can get up above the wake, the poor handling could be resolved and leave you with only a very nose high deck angle. Of course, it is very much counter to your thinking to be nose high, buffetting, and struggling with roll control to then pull further back on the stick while still hooked to the towplane.

This has mainly shown up (please correct me if I am wrong here) on newer Std Class planes with less wing incidence and less airfoil section camber in their wings. This improves high speed performance, but gives a more nose high attitude at low speed. And nose high at low speed on tow requires a lower tow position to be able to see the towplane and keep him safe while he is pulling you to altitude. So, you get closer to the wake, drop into it or start out in it when the towplane lifts off, and get into the controlability issues of low tow speed, particularly behind short winged tugs with more energetic wakes.

Steve