Sparrowhawk and airtow

Costello thinks it's probably safer too.

Interesting statement... how is that so?

BT

"Gary Boggs" wrote in message ...
We use a pay-out winch here in Hood River, Oregon at an airport and have no
problem with power traffic at all. We usually are using the winch when the
wind has picked up and there is almost no power traffic at these time at
all. We launch from the taxi way and have the required flashing yellow
light on our tow vehicle. It is much more neighbor friendly than using our
tow plane. I am convinced that it is much safer than an aero tow because
the climb is so steep that you either have plenty of room to land straight
ahead or plenty of altitude to make a 360 degree pattern. Costello thinks
it's probably safer too.

Gary,
What type of sailplane to you tow?
What type of pay out system do you use ?
Dan

Tony Verhulst wrote:
Bill Daniels wrote:

No winch? Buy or build one.


In the northeast US we have lots of trees and our airport is a
relatively narrow rectangular plot of cleared land surrounded by trees -
lots of trees. In any kind of cross wind, where would the winch rope
land after release? Right!

The glider grass runway is next to the paved runway used by the power
crowd. A paved taxiway leading from the paved rwy to the ramp crosses
the grass runway at midfield. The airport manager would, properly, be
not inclined to permit winch launching across an active taxiway.

There are lots of cases where a winch is not an option.

Tony V.

Our experience agrees with regulation. You need 30m (roughly 170 feet) between
the winch cable and the trees, and the winch cable and the runway. If you
measure you will probably find you do have enough space.

As for the cable landing in the trees, this depends on your design. We have a
huge open field, and a winch that is a bit slow on pickup/prone to looping. For
this situation we use a fighter (Dassault Mirage F1 FWIW) drag chute. This is
choked till it gives us a quick opening chute with a stable slow descent. When
you apply power, it comes down nice and controlled and keeps the cable under
tension, but in strong crosswinds it can have the cable only just clearing our
boundary fence about 250m away.

The general design is for a much smaller, heavier chute (700-800mm) that falls
much faster - and keeps the cable closer to where it was dropped. This of course
is the crux of the matter. A winch pilot who knows what he/she is doing will
launch upwind in a crosswind so that the cable falls toward the centreline. The
small chutes are made of a tough canvas and when they do land in bushes etc. the
general practice is to simply drag them free - making sure the area is clear and
it is safe to do so of course.

We simply do not launch if the crosswind component is too strong for safety. In
our case that is well before cable drift is a major problem.

On Mon, 14 Jun 2004 18:12:04 +0000, Robert Ehrlich
wrote:

OK, but problems come when you can't follow the normal procedure, e.g.
cable break.

Cable break IS as normal procedure.

Bye
Andreas

"Andreas Maurer" wrote in message
...
On Mon, 14 Jun 2004 18:12:04 +0000, Robert Ehrlich
wrote:

OK, but problems come when you can't follow the normal procedure, e.g.
cable break.

Cable break IS as normal procedure.

Bye
Andreas

Guys, check the German Dyneema tests. They aren't getting cable breaks.

Bill Daniels

Bill Daniels wrote:

"Andreas Maurer wrote:

Cable break IS as normal procedure.


Guys, check the German Dyneema tests. They aren't getting cable breaks.


That's abnormal!


Jack

On Tue, 15 Jun 2004 16:20:53 GMT, "Bill Daniels"
wrote:

Guys, check the German Dyneema tests. They aren't getting cable breaks.

Since these tests are carried out at my airfield (and sometimes I'm
using the Dyneema cable, too) I guess I know pretty well if there are
cable breaks or not.

Fact is that they have seldom cable breaks. Usually their cable breaks
only in places where it has been damaged before.

Unfortunately weak links still do break from time to time.
And unfortunately the cable break procedures must be trained as usual.


Bye
Andreas

Bill Daniels wrote:

Guys, check the German Dyneema tests. They aren't getting cable breaks.

No engine failures? NO "premature terminations of the launch" for any
reason AT ALL?

So the guys with the narrow strip in the trees don't have to make ANY
provisions whatsoever for early launch failures?

Graeme Cant

We are towing a 2-33 mostly. A couple of friends of mime built the winch
from plans they got from Barry Steele at Appropriate Engineering

As far as Costello thinking it's safer, that came from conversations I had
with them while I was obtaining insurance for my operation here in Oregon
and there is no additional charge to cover the addition of the winch
operation.


"Dan Goldman" wrote in message
om...
"Gary Boggs" wrote in message
...
We use a pay-out winch here in Hood River, Oregon at an airport and have
no
problem with power traffic at all. We usually are using the winch when
the
wind has picked up and there is almost no power traffic at these time at
all. We launch from the taxi way and have the required flashing yellow
light on our tow vehicle. It is much more neighbor friendly than using
our
tow plane. I am convinced that it is much safer than an aero tow
because
the climb is so steep that you either have plenty of room to land
straight
ahead or plenty of altitude to make a 360 degree pattern. Costello
thinks
it's probably safer too.

Gary,
What type of sailplane to you tow?
What type of pay out system do you use ?
Dan

"Graeme Cant" wrote in message
...
Bill Daniels wrote:

Guys, check the German Dyneema tests. They aren't getting cable breaks.

No engine failures? NO "premature terminations of the launch" for any
reason AT ALL?

So the guys with the narrow strip in the trees don't have to make ANY
provisions whatsoever for early launch failures?

Graeme Cant


Straw man argument.

Of course you train for premature launch failures - just like you do for
airtow. The original drift of this thread seemed to suggest that launch
failures were epidemic with winch launch.

With a well run winch operation the launch failures won't be any more common
than with air tow and the glider is more likely to be in a favorable
position to deal with them.

My remark about no launch failures was based on the German Dyneema test
group's reply to a question about how they dealt with breaks. Their reply
was, "we haven't had any."

Bill Daniels