Debacle: Flight test of Diana-2

Personally I think you are burying the hatchet deeply
for personal reasons, and I really believe you had no
intention to buy this ship. That said, lets look at your list.
Many of your suggestions are just common sense
stuff, but many are tainted with your personal feelings.

Item 2 is subjective at best. You may FEEL that
all controls should be of the auto-hookup type,
but that is not a certification requirement.
Your opinion here is irrelevant........

Item 4 is subjective at best. The aircraft meets JAR 22.

Item 5 is conjecture on your part. You are
presupposng a failure mode not in evidence
by inferring that it is problematic.

Item 8 is patently incorrect. Carbon structures do
not "store energy". Your description of the
failure mode shows a lack of understanding of
composite structures.

Item 13 is again subjective. Properly assembled trailing
edges do not delaminate regardless of their construction
method. Your presupposition that fabric wrapped edges
are superior is not based in fact, just an opinion you hold.
Attempting to show one Trailing Edge construction method
as superior to another again shows the limitations of your
composite construction background.

Item 15 is pure conjecture. You are asking that a JAR 22
aircraft manufacturer test for a condition that occurs only
when a pilot makes an error and flys the aircraft incorrectly.
IF this test was required, the conservative folks adninistering
JAR 22 would see that it was added to the cert plan. YOU
appear to be afraid of the small crosssection of the tail boom and
seem to be inventing a reason to make it appear less than desirable.

Item 17 is a prudent thought, but horribly skewed your personal
perspective. You said the paint is too thin. Compared to what??
Is that viewpoint based on cosmetics or a by a MIL thickness
check against the manufacturers recommended film thicknesses?
I suspect you have no idea how much or little paint is needed for
UV protection and what the finish requirements are.. Absent the
specific resin used and the finish content, you are in no position to
comment on UV protection issues. Yes you may FEEL the finish
was "very thin", but in fact, that is your PERCEPTION, not a fact per se.

I would hope that you would try to post facts on your site instead of
opinions.
It would be a nice change.........

pbc76049 wrote:


Item 4 is subjective at best. The aircraft meets JAR 22.

I'm not aware of any standardized crash testing procedure for gliders,
and if the the manufacturer of my ASH 26 E has knowledge of such tests,
they haven't shared it with any of the customers I know. It would be
wonderful if such data was available, but if you must have this data for
any glider in production, I think you will have pay someone to do a
crash test on it.

Unless you are an engineer competent in composite design for crash
protection, I don't think you will learn anything about the design by
asking "where the Kevlar is".


Item 5 is conjecture on your part. You are
presupposng a failure mode not in evidence
by inferring that it is problematic.

I don't think any of the manufacturers test their gliders until they
flutter, because it is very dangerous. The glider is likely to be so
damaged or uncontrollable, the test pilot will have to parachute out of
it. Certification requires testing to a certain speed beyond the Vne;
above that, and you are a test pilot. If you want to "know what margin
you will have when you are in an emergency" then you should fly so that
your emergencies do not exceed Vne. Even if the manufacturer the exact
flutter speed, he would be smart not to reveal that speed, for fear that
pilots would then use that speed as the "real" Vne.


Item 13 is again subjective. Properly assembled trailing
edges do not delaminate regardless of their construction
method. Your presupposition that fabric wrapped edges
are superior is not based in fact, just an opinion you hold.
Attempting to show one Trailing Edge construction method
as superior to another again shows the limitations of your
composite construction background.

My ASH 26 E does not use fabric wrapped trailing edges, nor did my ASW
20, yet they both seem like fine machines. I would feel rather foolish
telling Gerhard Waibel or Martin Heide the proper way to build a glider!

It appears Neshe sets very high and very unusual standards for a glider.
If I were a glider manufacturer, I would pray he became interested in
some other manufacturer's glider.


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Hi Eric,

On Sun, 16 Oct 2005 20:48:49 -0700, Eric Greenwell
wrote:


Unless you are an engineer competent in composite design for crash
protection, I don't think you will learn anything about the design by
asking "where the Kevlar is".

Well... extremely light weight of a fuselage definitely makes me
wonder about crash protection - something Germany glider manufacturers
have a lot of experience with. I think there's a good cause why their
gliders are so heavy compared to the Diana 2.


I don't think any of the manufacturers test their gliders until they
flutter, because it is very dangerous.

Wilhelm Dirks did that with the DG-600...

Flutter testst are not performed inflight, but any aircraft needs to
perform static flutter tests before it's certified in Germany (a very
expensive thing to do - these tests are usually performed by Prfessor
Niedbal).

Even if the manufacturer the exact
flutter speed, he would be smart not to reveal that speed, for fear that
pilots would then use that speed as the "real" Vne.

The design maximum speed is Vne + 15 percent - this is what the glider
is designed for (and being flight-tested). Obviously this is the
proven speed where no flutter occurs... at least in a perfectly
maintained (prototype) glider.
I certainly wouldn't risk to fly that fast... do you think that
someone is so stupid to exceed Vne? I think most flutter cases happen
at speeds between Va and Vne due to unexpected turbulence.



Bye
Andreas

At 12:00 16 October 2005, Ian Johnston wrote:
On Sat, 15 Oct 2005 16:38:08 UTC, Don Johnstone
wrote:

You have to be kidding. Whatever happened to 'the
customer
is always right'.

It's a load of nonsense. No-one has a right to fly
any aircraft.

Ian

What you say is absolutely true but on the other hand
no-one is forced to buy it either. If the company do
not sell aircraft they have failed in their aim and
lets us be frank this company are not Schemp Hirth,
DG-Flugzeugbau / Glaser-Dirks or Schleicher and do
not have a track record of building excellent gliders.
I would have thought that a company trying to sell
a new glider would want to encourage sales but obviously
my idea of business is outdated. What ever the rights
and wrongs it does not seem to me that the manufacturers
of the Diana 2 are going out of their way to encourage
customers in fact I detect a certain arrogance in their
approach. Building gliders does not make money, you
actually have to sell them, and what does this debacle
say about their likely after sales service I wonder.
If someone who wanted to sell me a glider would not
let me fly it I would certainly take my money elsewhere.

At 13:00 17 October 2005, Chester D wrote:
Stefan schreef:

Alexander wrote:

The testing customers were positively thrilled about
the way Diana 2 is
flying. Some feedback: the glider is easy to fly
and also safe. None of
the pilots (among them also competition pilots and
instructors) could
make the glider spin or stall completely.
...
Mr Sharma said to me personally that he had only
200 hours and
no experience on racing class gliders.

Hmmm... Now, you must decide: Is that glider (15m!)
'easy and safe to
fly' or do you need more than 200 hours to be able
to handle it?

Stefan

There are plenty of glider pilots, even with 500 hours
or more who
can`t handle performance gliders. They can in common
situations like a
local flight but when in trouble the plane is too fast,
too nervous,
just too hard for them to handle.

We are not talking open class here, the Diana is a
15 metre glider, unflapped with a claimed LD of 50.

Nothing special about that except the performance so
what is so difficult. I don't hear people saying that
a Discus (1 or 2) LS8 or any of the Scheilcher gliders
are anything but straightforward providing the pilot
has received the proper training.
One wonders what makes this glider so different from
those marketed by the established manufacturers apart
from the seeming determination of the makers to only
sell to those they deem suitable. No wonder that gliding
is in decline if it is so difficult to find someone
who is prepared to treat customers as a valuable commodity.
However good the product an uncaring and arrogant supplier
will put me off every time.



Most of those pilots know that themselves, others buy
a glider and get
scared in flight, few try to test-fly someone elses
glider.

Not the case here is it.

"Don Johnstone" wrote in
message

We are not talking open class here, the Diana is a
15 metre glider, unflapped with a claimed LD of
50.
Nothing special about that except the performance so
what is so difficult. I don't hear people saying that
a Discus (1 or 2) LS8 or any of the Scheilcher gliders
are anything but straightforward providing the pilot
has received the proper training.

Heres the rub, you said proper training.
The owner didn't let him fly.
There are conflicting reports on flying ability.
The owners, if they made a mistake, erred on the side of caution.
TOTALLY UNDERSTANDABLE ACTIONS.

The pilot who didn't fly is ****ed off and making a lot of noise about it.
TOTALLY UNDERSTANDABLE ACTIONS.

What I have a hard time with is the "tire kicker" rooting around
and using his OPINIONS to slap around a sailplane. If he has
technical issues of merit, he is doing us a favor by posting them, but
as most here can see., he is acting childishly and with vindictiveness.

I'm done here and hope everyone else is also..........

At 20:06 17 October 2005, Ian Johnston wrote:
On Mon, 17 Oct 2005 10:09:02 UTC, Stefan
wrote:

Hmmm... Now, you must decide: Is that glider (15m!)
'easy and safe to
fly' or do you need more than 200 hours to be able
to handle it?

200 hours in 1250 flights is quite suggestive, don't
you think?

Ian

Sorry, I don't get it. Suggestive of what?

On Mon, 17 Oct 2005 21:15:29 UTC, Don Johnstone
wrote:

At 20:06 17 October 2005, Ian Johnston wrote:

200 hours in 1250 flights is quite suggestive, don't
you think?

Sorry, I don't get it. Suggestive of what?

Quite a lot, really. 9 minutes 36 seconds per flight, on average.

Ian

"Don Johnstone" wrote in
message ...
At 20:06 17 October 2005, Ian Johnston wrote:
On Mon, 17 Oct 2005 10:09:02 UTC, Stefan
wrote:

Hmmm... Now, you must decide: Is that glider (15m!)
'easy and safe to
fly' or do you need more than 200 hours to be able
to handle it?

200 hours in 1250 flights is quite suggestive, don't
you think?

Ian

Sorry, I don't get it. Suggestive of what?



An Air Cadet ?

At 14:12 17 October 2005, Don Johnstone wrote:

We are not talking open class here, the Diana is a
15 metre glider, unflapped with a claimed LD of 50.

Nothing special about that except the performance so
what is so difficult. I don't hear people saying that
a Discus (1 or 2) LS8 or any of the Scheilcher gliders
are anything but straightforward providing the pilot
has received the proper training.

Don get your basic facts right matey - Diana is a FLAPPED
15m glider!!