Thermal right, land left

Wow, there have been some absolutely excellent posts on this
thread. Thank you to all those who contributed...
--

------------+
Mark Boyd
Avenal, California, USA

"cernauta" wrote in message
...
"Bill Daniels" wrote:

Tape two yaw strings (which then become pitch strings) on each side of
the
canopy at the lowest and most forward part you can still see.

The string angle difference between minimum sink and stall is large so
the
bright red, wiggling strings angled up steeply are a good visual stall
warning.

That must be true only for unflapped gliders, or it's valid only for
one specific flap setting in a flapped glider. Or you have to make
different coloured markings for each and every flap setting.

Aldo Cernezzi

You're right about flaps making a difference in the calibration. I've only
tried this on two flapped gliders and one without flaps. However, It seemed
to work pretty well in all cases. I actually didn't see too much difference
in the string indications at different flap settings.

The flap issue is partly moot since the flap settings are related to
airspeed bands. Stall concerns would likely arise only with the flaps in
their most positive two settings, landing or slow thermalling. The
near-stall indication is very obvious.

Bill Daniels

On 3/14/04 6:54 AM, in article ,
"Robertmudd1u" wrote:

Too many people in this sport think you need ALL the bells and whistles and a
$100,000+ glider to be a "real" glider pilot. That attitude is hurting us.

Right on! And exactly why we get so many arrogant and ultimately ignorant
remarks concerning the so-called inadequacies of the PW-5. Clearly, too many
people don't understand the concept of competition. It is not about what you
show up with on the trailer, but about what you can do with it in the air.
Neither the choice of the PW-5 nor the parameters established for the WC
Glider selection process are the source of the problem.

The "Mine is bigger than yours," syndrome will ruin the World Class just as
it has ruined other forms of vehicle-based competition. Classes which were
originally established to facilitate development of skill and commitment to
a sport at reasonable cost are falling prey to the "too much money and not
enough character" syndrome on every side. The bitter and unreasoning
criticisms of the PW-5 on this forum are clear evidence of the kind of
distorted personalities which are behind this unfortunate phenomenon.

People who are real competitors are competitive on skateboards, lawnmowers,
1-26s, or jet fighters, and using the excuse that the equipment is not up to
your exalted standards is, on its face, little more than a childish excuse
for personal inadequacy.


Jack

Hi again Robert.
Read your thread not good enough I guess. Sorry for that.
Nice to understand that you are using yourself an airbrake/gear warning
system.
Indeed a warning system for unlocked or extended airbrakes on fixed gear
gliders would do a good job too.

Karel, NL


"Robertmudd1u" schreef in bericht
...
Hi Robert,

Read the story at http://home.wxs.nl/~kpt9/gear.htm and you may have
second
thoughts.

Karel, NL


Sorry Karel, I am missing your point. I did not say such systems were not
a
good idea just that they need to be designed for fixed gear glider too,
and not
be expensive. On my retractable gear glider I do have a warning horn for
airbrake and landing gear.

The information in your link is interesting, Ia m sure some will find the
schematic valuable. I sure saved it.

Robert Mudd

I think you are missing the point that most people
have made about the PW5, those that aren't ignorant
anyway. The point is that it does not perform well
enough to justify the price tag. I cannot understand
the mentality of people who would rather fork out £20k+
for a sailplane with the performance only slightly
better than a K6e when they could get a second hand
LS4 or ASW20 for the same or less money! I would have
thought that a one-type class based on an existing
design (which could be very cheaply put back into production)
would make far more sense. After all, some of us can't
even afford a brand new PW5, but can afford an old
ratty ASW20 or LS4.
This is not about elitism in terms of money, its about
common sense and value for money. The PW5 has an abundance
of neither.
LS4 for the world class!

At 22:18 14 March 2004, Uri Saovray wrote:
Speaking of simple warning devices:
How about a simple hookup to a horn which is activated
when the
airbrakes are opened while the towhook is engaged (i.e.
open spoilers
during tow)?
A microswitch on the airbrake levers would be the no-brainer
part.
What about the towhook? Magnetic sensor? where? How?


Other ideas?


how about the last 'B' in CB-SIFT-CB i've always found
it to be a no-brainer personally, and its completely
free! Usually accompanied by the guy who attaches the
towrope/cable saying that phrase 'brakes closed and
locked?'

Jack,

You are right. I take back everything I have said
about the PW5.

Now, if you will excuse me... Me and my distorted
personality need to get back to writing letters to
Schumacher and Barrichello informing them that their
'Mine is bigger than yours' attitude is ruining Formula
One. Whilst I am at it, I might inform John Coutts
(top ranked glider pilot in the World) that he has
'too much money and not enough character'.

Are you honestly suggesting that people should WANT
to sell their beautiful German sailplanes and buy PW5s?

Have you ever flown a glider?

Ben.


Right on! And exactly why we get so many arrogant and
ultimately ignorant
remarks concerning the so-called inadequacies of the
PW-5. Clearly, too many
people don't understand the concept of competition.
It is not about what you
show up with on the trailer, but about what you can
do with it in the air.
Neither the choice of the PW-5 nor the parameters established
for the WC
Glider selection process are the source of the problem.

The 'Mine is bigger than yours,' syndrome will ruin
the World Class just as
it has ruined other forms of vehicle-based competition.
Classes which were
originally established to facilitate development of
skill and commitment to
a sport at reasonable cost are falling prey to the
'too much money and not
enough character' syndrome on every side. The bitter
and unreasoning
criticisms of the PW-5 on this forum are clear evidence
of the kind of
distorted personalities which are behind this unfortunate
phenomenon.

People who are real competitors are competitive on
skateboards, lawnmowers,
1-26s, or jet fighters, and using the excuse that the
equipment is not up to
your exalted standards is, on its face, little more
than a childish excuse
for personal inadequacy.


Jack

Jon Meyer wrote:

I cannot understand
the mentality of people who would rather fork out £20k+
for a sailplane with the performance only slightly
better than a K6e when they could get a second hand
LS4 or ASW20 for the same or less money!

While I agree that LS4 for the world class might have been the best
solution (provided production plans were made available to any builder
anywhere in the world), there are many countries mostly outside Europe
where good, used gliders are not available today, and importing from
Europe is not economical because of huge taxes and duties.

The PW5 isn't an appealing glider, but it's today the only
certificated glider you can build anywhere in the world. We must think
world-wise if we want to create an opportunity for development of the
sport.

Aldo Cernezzi

Bill,

Are you still using the AOA indicators made from yaw strings? Which
glider type is it mounted on?

I assume these strings would be forward, so you visualize them at the
same time you see the normal yaw string. Is that correct?

John

"John" wrote in message
om...
Bill,

Are you still using the AOA indicators made from yaw strings? Which
glider type is it mounted on?

I have tended to use them with new gliders to calibrate my seat of the pants
feel near a stall. Once my senses are atuned to the glider the strings are
no longer neccessary. I have tried them on a Lark IS28, Blanik L-23 and a
Nimbus 2C. The string indications were simular on all.

I assume these strings would be forward, so you visualize them at the
same time you see the normal yaw string. Is that correct?

The strings need to be as far forward as possible to get away from the
near-field flow over the wing. If I recall my Aerodynamics 101, the perfect
place for an AOA sensor would be about 10 wing chord lengths ahead of the LE
on a nose boom. The best practical position is near the forward end of the
canopy side frames. This happens to put them in the pilots field of view.

The 3D flow over the glider's nose seems to amplify the response of the
strings to changes in AOA so don't expect the string angles to represent the
actual AOA. While the absolute accuracy is terrible, the indications are
very repeatable and once calibrated to the three critical AOA's, they do
give useful data.

The biggest problem is that they are highly sensitive to yaw angles but if
both strings are giving the same indication, the yaw error is cancelled out.
Another nuisance issue is that the strings tend to get sucked under the
canopy frame as it is being closed trapping the strings.

Bill Daniels