I probably should resist the urge to jump in on this thread, but what
the heck. I've made several hundred aerotows using CG hook only
equipped gliders, and have had exactly 3 incidents which might have been
avoided with a nose hook. Two were my first flights in newly purchased
gliders, where I guessed wrong about the takeoff trim position, got
quite high on takeoff, but managed to recover with full forward stick.
The other time I got sideways early in the ground roll with half water,
released, and got stopped before going too far off the runway.

Being the skeptical sort, I went to the US National Transportation
Safety Board site, and did a query for all reports of accidents during
the past 20 years with the words "tow" and "glider" in them. This
yielded 280 hits. I eliminated those accidents that happened after safe
release, where there was a mechanical failure (disconnected controls,
etc.), where one of the pilots was likely to be impaired (heart attack,
etc.), or where the glider ran off the side of the runway early in the
takeoff roll. This left 17 accidents. Of those, 8 gliders (two
probably with CG hook, one more possible) had large pitch excursions on
takeoff, were released and subsequently crashed without damage to the
towplane.

That left 9 in which a glider high and out of position pulled up the
tail of the towplane causing it to crash. Of these, 3 very likely had
CG hooks (Std Cirrus, Open Cirrus, Ka-6E), 2 likely had nose hooks
(G103C and 1-26), and the remainder either the glider type was not
stated, or may have had either type of hook (Twin Astir).

The thing that struck me about these accidents was how many of them were
due to the pilot fiddling with an open canopy, or inadvertently deployed
spoilers. If the pilots simply payed attention to flying the aircraft,
most of the above would never have happened. The other thing that is
clear is that those freakin' Schweizer towplane hooks are a menace to
tow pilots, and *should* be banned.

These statistics don't suggest to me that we should prohibit aerotow of
CG hook only gliders in the US. A significant proportion of the single
seat gliders here only have CG hooks, as some of the European
manufacturers charged a fairly hefty premium to put in a nose hook until
recently (if they offered them at all), and, well, a lot of glider
pilots are kind of cheap.

As for the other side of the Atlantic, it would be interesting to see
some actual statistics...

Marc