Glider crow-hops:

On 8/23/2012 11:07 AM, Bill D wrote:
On Thursday, August 23, 2012 8:44:06 AM UTC-6, JohnDeRosa wrote:
John C's comments are well said.

A few extra thoughts of my own.

"crow hops" (near heard that term before but I get it) might equate to a
"high speed taxi" which is how the general aviation (GA) powered crowd
might take a few hops off the runway to test the new hardware. This
might work for self powered aircraft but not for a (non-powered) glider.

Think about a glider on a tow rope behind a tow plane. Having the tow
plane pull you to take off speed, then you come back down and both you
and the tow plane need to come to a halt in unison. The take off is the
trickiest thing to master anyway, these hops you suggest would be REALLY
tricky.

Of course there is this aspect of the first flight in a single place
glider which very few powered GA pilots have ever experienced. Nearly
all of them have flown with someone else in a 2 place before soloing it.
Even a single place Pitts has a two place equivalent. The point is that
gliders are different beasts with special needs. I don't mean to scare,
just to get specialized training.

So, anyway, the common course of action is to take a high tow (5,000 ft
AGL) early or late in the day, while pretending to execute landing
patterns multiple times as you descend. That and a good briefing of the
ship beforehand by the POH and an instructor you trust. Especially if
this glider of yours is a CG hook and you have never flown one before.

Good luck and stay safe.

- John DeRosa

Guys, I don't think you do "get it".

First, this is never done using a tow plane. It is not "teaching yourself
ground launch" since it's not a 'launch'. It does not involve enough energy
to endanger the pilot or glider. Once upon a time, this is how everyone
learned to fly a glider. A tow car is used only if a bungee is
unavailable.

The glider never gets more than a few inches above the runway nor more than
40 knots. It is done in steps starting with a ground roll just fast enough
for aileron control and, if things go well, increasing to just barely
liftoff speed. If the glider pilot starts to "lose it" the tow car
releases the rope and stops well clear as the glider stops. It is never
done in proximity to obstacles the glider could collide with.

It's best done in the early morning with a headwind which keeps the ground
speed down.

I did this hundreds of times with an experimental flying wing sailplane as
pilots learned its unconventional handling characteristics. No one had a
problem, the glider was unscathed and all quickly gained the skills to fly
the glider well. If the pilot was really inexperienced, I did a couple of
dual "ground slides" and "crow hops" in a 2-seat trainer to get them used
to the idea.

Northern European countries like Lithuania still do this with primary
gliders. Even young children learn to fly them. Google "LAK 16" videos.


It CAN be fun to arrive late to the party. :-)

So now that you've received advice spanning the entire spectrum, how best to
sort it out?

My - utterly free, complete with money-back-guarantee - advice includes:

1) The devil is ALways in the details, and I haven't seen any advice I'd say
is flat out "wrong"...even though plenty of it is conflicting. There
definitely are some useful lessons therein... Proceed accordingly.

2) Yes, you'll be transitioning to a new-to-you single-seat sailplane, but
(based on what you originally wrote) not to a new-to-flight sailplane. I and
every previous responder have done that multiple times; it's one of the
personally intense joys of this grand sport. Point 'A' being, it's not THAT
big a step into the unknown, given many do it safely every year, all around
the globe. Certainly it's not in the same category as acting as a test pilot
to a new-type-sailplane. Point 'B' being there are some sound reasons
supporting the fact most pilots today transitioning to ships of the
performance of your Apis 13M do NOT use the "crow hop" approach. One is that
very few have direct experience with it anymore. (Blame this on the advent of
2-seat trainers post-WW-II. Bill D. - whose aviation [power &
glider]/instructor experience I seriously respect - is an exception, and, note
his referenced "crow hop" experience had both more direct availability of
people with similar experience [because it was decades ago], and, involved
test-flying a new, non-standard/flying wing design. Very prudent
decision/approach under those circumstances, IMHO. Why would you want to
involve yourself with others equally new to what *they're* doing [i.e. "crow
hopping"] as you will be to what *you're* proposing doing? Knee jerk answers
will be downgraded.) Meanwhile John C. touched upon a 2nd reason most
transitions as you've asked about are TODAY arguably most safely done by high
aero tow...i.e. rapidly getting as far away from big, hard things you can hit,
using a tow method with which you (and others) are thoroughly familiar with is
prudent indeed.

3) Brad (Hill - builder/pilot of an Apis 13 w. 800 hours on it & a prior
responder in this thread) apparently used John C.'s recommended approach to
his first flight in his Apis. He alluded to why. Most Definitely pick his
brains before you make your transition flight. Be sure to ask not only "what"
but "why?"

4) If you haven't already, be sure and have a discussion about "PIO" with your
instructor(s) regardless of which approach you pursue.

Have fun! (Just to be anal, I'll note that you won't have much fun if you
crunch something, so there's no need for me to advise, "Be safe!")

Bob W.