In rec.aviation.student Dan Luke wrote:
Oh, well; another lesson learned. "Controls free and correct?" Maybe at the
moment you check, but watch out for anything that could interfere with them
while you're not looking.

Thanks for the story. Scary! I'm glad it worked out ok in the end.

You'd think I would have learned from it, but I had a somewhat similar
incident just two days ago, although mine was badly exaggerated by
stupidity on my part.

First, some context, for those unfamiliar with gliders. The takeoff is a
tricky operation, since you're balancingon a single wheel, and you're
effectively taking off in formation. There's usually a wing runner holding
the wing up at the start, but he can't keep up for long, and when he lets
go you usually need full control deflections to stay straight and level.
This lasts a couple of seconds, then airspeed builds up to needing only a
feather touch. The glider will lift off well before the tow plane due to
different stall speeds, and the ideal altitude for that phase is literally
about 5ft AGL. The ground provides an obvious lower bound, and if you get
too high you can pull the tow plane's tail up and smash his nose into the
pavement.

I always carry a 100oz Camelbak with me, having lots of water is handy
when you don't know how long you'll be in the air or where you might land.
I had been lying it horizontally next to the seat, but the hose wasn't
quite long enough in that position and I had to bend down to drink. This
time I decided to stand it vertically.

I was flying a Schweizer 1-26 where the stick always hits the knees when
going side to side. This doesn't limit control freedom to any significant
degree but I've become used to hitting my legs whenever I test the
controls.

During the takeoff roll I realized that this knee banging problem was
worse than usual. Oops! The top of the Camelbak was right behind my knee,
pushing it toward the stick, and limiting my controls for real. It wasn't
bad enough to pose a danger, especially on a calm day like Saturday, but
it was worrying.

The fix is easy enough, right? Just reach over there with the other hand
and pull it back out of the way. Of course it's not that easy, things get
in the way, and there are these armrests... CRAP! A moment's inattention
and I'm way too high and the tow plane is still on the ground. Of course I
overcorrect and head down too fast. I correct again but a bit too late,
and hit the ground with a thump that's painful to hear but probably not as
bad as some landings I've had.

Lesson learned, I leave the stupid water bag alone and do what I should
have done from the start, and fly the airplane. Once I get off tow the
thing is easy to move, and the rest of the flight is uneventful. (Too
uneventful, really; no thermal activity to speak of.)

It was a dumb thing to do but luckily I got taught a lesson in the best
way and nothing got broken.

--
Michael Ash
Rogue Amoeba Software