WOW!

On Wed, 01 Nov 2006 07:43:51 GMT, Jack wrote:

He can do a conventional approach, when he must. Can all of us do his
preferred "high-energy" approach, safely, consistently? If so, then we
are better qualified to criticize.

Why would anyone do such an extreme approach at all?
Depsite all his well-written words, there is no chance that he is able
to perform a spot-landing this way.

Not to mention his surprise if he should try this in a high
performance ship with an L/D beyoond 35... lol.






Bye
Andreas

Bob C wrote:
Very well written article.

Bob, I beg to differ.It is a terribly written article!I have been at
this a long time, and I have seen this type of pilot before.What the
author is doing is using faulty logic and baseless asumptions to
justify a completely non standard way of doing things.The author
addressed a couple of issues with this approach method while completely
ignoring others.

This is a 'standard' airshow
sailplane approach.

Bob, should we all fly like we are at an airshow?I have seen two power
fatalities and a near fatal glider crash at fly ins where pilots were
doing "Standard" airshow stuff.

Gives you exceptional glidepath control, excellent
control authority and makes a stall/spin highly unlikely
(though not impossible). One of my tricks for setting
up a perfect spot landing.

Now you Bob (Just like the original author) are applying some faulty
logic.You tout the percived benifits of this approach while ignoring
the fact that it creates more hazards than it solves.

That being said; as with any new technique, don't try
it the first time without the assistance of someone
experienced in the technique.

Or better yet, dont try it unless you have a specific reason to.

It may be possible to overstress the
glider. Be extra cautious of this technique when switching
from a 2-33 to a higher performance glider. The extra
energy you're carrying may be more than you realize.

No argument here!I think this stunt would only work with a small range
of training ships or a looooong runway.Not to mention the fact that the
author is flying outside the POH and FARs AIM etc..

There are advantages in learning where the edges of
the performance envelope are, but explore carefully
with the help of an experienced pilot.

There certainly are, but not in the traffic pattern!

Being comfortable
on a fast, low approach might come in handy when you
discover power lines while setting up an out landing.

But it will have the oposite effect with a more likely senario like a
fence or ditch at the other end of the approach.

Fly Safe,
K Urban

I am no instructor, but this seems to be a poor display of how not to
land a low-performance glider on a long runway.
It would not be a good technique for a high performance glider in a
small outlanding field.
=20
I fly from a hill-top site with plenty of wind gradients and cliffs and
forests for under/overshoot.
Yes, the recommended 1/3 wind speed added to the approach speed but not
this.
=20
I think this pilot needs some instruction on better circuit
planning/energy management, if he is going to fly other gliders (or
aircraft)
and if he is receptive to comment. I agree with the instructors who
consider this a "fail".
=20
Unimpressed.
=20
Rory=20
=20
=20
At 21:48 31 October 2006, wrote:
Here is something you more experienced pilots might
want to comment on.
Being a pilot of much less experience, it just looked
like an
interesting thing to see comments on some of the points
the pilot
makes.. I came across this 2005 article while just
wandering about on
the web. Scroll down to the high speed approach article.

You'll need acrobat reader.

http://www.pugetsoundsoaring.org/new...ow_10_2005.pdf

I agree as well, to a certain extent.

High speed approach breaks down with higher speed gliders -- a point
drilled into me when I was a primary student 20 years ago (energy =
1/2mv**2, so picking up 5 extra knots over the 50 knot standard
approach speed of a K21 results in 21% more energy, resulting in
landing waaay down the runway).

However, there are a couple of cases where zooming to higher airspeed
is needed, and it's important to point these out. Reichmann describes
the most extreme of these in "Cross Country Soaring" in his outlanding
section. If an obstacle is recognized while on short final, the pilot
can dive at the obstacle and use the extra kinetic energy to make a
low-G parabolic maneouver over the obstacle. He also describes a
lesser version in coping with steep landing fields -- if you have to
land uphill on a steep slope you should zoom towards the slope so that
you have extra energy to make the more exaggerated flare required.

I've also had to use the technique to cope with extreme sink on short
final a few times over the years. In my early years I flew at Harris
Hill, which had a really bad downwash on short final with certain wind
conditions. More recently I had a student act backwards when he
encountered a downwash on final. I kept saying "faster", but he kept
pulling the stick back, until I had to take the plane and make a zoom
approach.

Which brings up the reason we should at least discuss this with all our
students. Without some training on the issue, they will tend to react
to sink in the pattern by pulling back on the stick, which leads to low
stall/spin accidents or hard landings when they don't have the energy
to flare. It's vital to push the stick Forward! in sink, even when
you're low.

-- Matt McKrell CFIG

KM wrote:
Bob C wrote:
Very well written article.

Bob, I beg to differ.It is a terribly written article!I have been at
this a long time, and I have seen this type of pilot before.What the
author is doing is using faulty logic and baseless asumptions to
justify a completely non standard way of doing things.The author
addressed a couple of issues with this approach method while completely
ignoring others.

This is a 'standard' airshow
sailplane approach.

Bob, should we all fly like we are at an airshow?I have seen two power
fatalities and a near fatal glider crash at fly ins where pilots were
doing "Standard" airshow stuff.

Gives you exceptional glidepath control, excellent
control authority and makes a stall/spin highly unlikely
(though not impossible). One of my tricks for setting
up a perfect spot landing.

Now you Bob (Just like the original author) are applying some faulty
logic.You tout the percived benifits of this approach while ignoring
the fact that it creates more hazards than it solves.

That being said; as with any new technique, don't try
it the first time without the assistance of someone
experienced in the technique.

Or better yet, dont try it unless you have a specific reason to.

It may be possible to overstress the
glider. Be extra cautious of this technique when switching
from a 2-33 to a higher performance glider. The extra
energy you're carrying may be more than you realize.

No argument here!I think this stunt would only work with a small range
of training ships or a looooong runway.Not to mention the fact that the
author is flying outside the POH and FARs AIM etc..

There are advantages in learning where the edges of
the performance envelope are, but explore carefully
with the help of an experienced pilot.

There certainly are, but not in the traffic pattern!

Being comfortable
on a fast, low approach might come in handy when you
discover power lines while setting up an out landing.

But it will have the oposite effect with a more likely senario like a
fence or ditch at the other end of the approach.

Fly Safe,
K Urban

Eric Greenwell wrote:
32 mph over Maneuvering speed is a mite fast? What's Vne?

Eric, VNE is Velocity Never Exceed.It is the max indicated speed at
which you can fly.

Fly Safe,
K Urban
(Just Yukkin it up here)

KM wrote:
Eric Greenwell wrote:
32 mph over Maneuvering speed is a mite fast? What's Vne?

Eric, VNE is Velocity Never Exceed.It is the max indicated speed at
which you can fly.

Not a well-phrased question, apparently: I wanted to know the Vne for
the 2-33 glider.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

As Zulu pointed out, the Va speed of a 2-33 is only 65 MPH. The Vne is only
98MPH. That's when they were NEW!

The 2-33 is an old glider and the years have not been kind to them. Many
are showing obvious signs of metal fatigue in the upper wing skins. I know
of several that have a dozen patches in the "D" tube.

My personal rule is to NEVER fly a 2-33 faster than Va. I think it's a real
problem that many tugs can't comfortably tow a 2-33 slower than its Va
airspeed since you may well need full control deflection on aero tow.

Flying a pattern and approach at 85 in a 2-33 is insane. Given their age
and condition, it's only a matter of time before some cowboy pulls the wings
off one.

Bill Daniels


wrote in message
oups.com...
Here is something you more experienced pilots might want to comment on.
Being a pilot of much less experience, it just looked like an
interesting thing to see comments on some of the points the pilot
makes.. I came across this 2005 article while just wandering about on
the web. Scroll down to the high speed approach article.

You'll need acrobat reader.

http://www.pugetsoundsoaring.org/new...ow_10_2005.pdf

wrote:
Here is something you more experienced pilots might want to comment on.
Being a pilot of much less experience, it just looked like an
interesting thing to see comments on some of the points the pilot
makes.. I came across this 2005 article while just wandering about on
the web. Scroll down to the high speed approach article.

You'll need acrobat reader.

http://www.pugetsoundsoaring.org/new...ow_10_2005.pdf

Leaving aside other real concerns (e.g. flying 20 mph above Va in the
turbulence of hills and trees) and the spurious concerns (e.g. frozen
divebrakes), we're left with a pilot who has a fundamental
misunderstanding of glider performance in ground effect. I don't
have the energy (pun intended) to play with the numbers in his scenaio
to show exactly how L/D at 85mph over the threshold at height X vs.
the more conventional 55 mph or 60mph over the trees at height Y work
out. He will argue that he can achieve an L/D of 5:1 vs. 8:1 for the
conventional landing. He'll then point out that he will glide only
200 feet from treetop height vs 400 feet for the conventional landing.
Something like that.

The problem is, what does it take to stop from 10 feet and 55mph vs.
10 feet and 85mph? Since L/D in ground effect increases significantly
(where significantly is anywhere from 20% to 30% for high-aspect ratio
airfoils), the amount of time that you spend decelerating in this
higher lift condition is extremely important to overall stopping
performance. Anecdotally, we all know (or should know) that the
"float" in ground effect will greatly outweigh the advantage (if any)
in this approach.

I suspect the author will argue that there's nothing wrong with just
flying it on "smoothly" at 70mph and letting the wheel brake and skid
do their thing. I sure hope he's not expecting to hold the ship at
5 feet and ever so slowly rotate while mainting 5 feet as the aricraft
slows down from 85mph to a more reasonable 40mph or less touchdown
speed. If so, I challenge him to accomplish any landing over a 30
foot tree line in less than 1,000 feet. Of course this works fine on
the airshow circuit or at a field with clear approaches as an exercise
to show the performance boundaries of the aircraft. Let's not
discuss what happens in a rough field or a short field :-)

Bill Daniels wrote:

Flying a pattern and approach at 85 in a 2-33 is insane. Given their age
and condition, it's only a matter of time before some cowboy pulls the wings
off one.

Bill Daniels

Those Schweizers are pretty stout. He will probably only be able to
bend them badly unless his horse is riding along in the back seat too.

Seriously, I totally agree with you Bill. It's nuts.

Hey, did your email change? Been hoping to hear back from you on the
Amazing Lark Rigging Aids question.

Matt Michael wby0nder@ A Oh L dot com