It appears that a third S-H aircraft has broken up in flight this
season. Rather than giving private assurances/explanations to
individual S-H owners, could someone in-the-know please tell us what
is going on?

Schempp-Hirth updated its homepage today with information concerning the
Discus CS incident.
http://www.schempp-hirth.com/de/index.html
Available in German, I guess an English translation will follow. BTW:
The pilot bailed out successfully.

Stefan

Rough translation of the Schempp Hirth notice:
During a flight in turbulent air in Southern France a Discus CS went into an
uncontrolled flight attitude. During the following recovery maneuver the
outerwing broke off 3.80 m from the wingtip. Within the range of the
location of fracture, a defect in the gluing of the spar boom was
determined. The pilot fortunately saved himself with his parachute. Due to
this incident, the airworthiness of Discus CS series is withdrawn, since a
production defect cannot be excluded. The instructions for airworthiness
(airworthiness directives) Nr.2003-265 and Nr.2003-266 were likewise
extended for some Discus b and the motorglider Discus built with the wings
of the Discus CS bT. The withdrawal of the airworthiness will be limited up
to the time the wings can be examined and repaired where necessary. At the
moment we can unfortunately give no data for the necessary corrective
measures, since the responsible office for air in Tschechien must agree with
all actions and an appropriate work date (with LBA, BFU, and SHK) by this
Czech authority unfortunately can be done only after September 24th. The
appropriate TM to this procedure can be published therefore only after this
date. As soon as we have further information, we will report immediately
here
"Chris OCallaghan" > wrote in message
om...
> It appears that a third S-H aircraft has broken up in flight this
> season. Rather than giving private assurances/explanations to
> individual S-H owners, could someone in-the-know please tell us what
> is going on?

At 19:12 17 September 2003, Stewart Kissel wrote:
>F. Fuchs has the links to two separate Discus events
>in his recent post-g=
>o into the current Discus thread.

Stewart,

I think that what you are looking at is actually the
two separate LBA ADs required to cover the grounding
of all the Disci with Czech wings. Most of them are
Discus models but there are some Discus BTs with Czech
wings. They are certified as different types and so
have to have separate ADs.


John Galloway

John,
If you are still wondering about the 4DM breakup, read the NTSB report.
From reading the report, the plane did not fail.

Mark

At 02:42 18 September 2003, Janus2k wrote:
>John,
>If you are still wondering about the 4DM breakup, read
>the NTSB report.
>From reading the report, the plane did not fail.
>
>Mark
Actually the wings did fail. They presumably failed
above their design load limit. but they still failed
in flight causing the crash. A better question would
be, how much of a design cushion is there between the
load limit and actual failure of the wing?

Th DG website has an article and video of the destruction testing of the DG
1000 wing during certification. Also a section on the Fuse tests and a link
to another page regarding the regs the all gliders are built to.
Worth a read. The video is spectacular.
URL is http://www.dg-flugzeugbau.de/ Then click on DG 1000 and its there.
Cheers
Paul


"Steve Davis" > wrote in message
...
> At 02:42 18 September 2003, Janus2k wrote:
> >John,
> >If you are still wondering about the 4DM breakup, read
> >the NTSB report.
> >From reading the report, the plane did not fail.
> >
> >Mark
> Actually the wings did fail. They presumably failed
> above their design load limit. but they still failed
> in flight causing the crash. A better question would
> be, how much of a design cushion is there between the
> load limit and actual failure of the wing?
>
>
>

>From: (JDFlishall)
>Date: 9/17/2003 6:53 PM Pacific Daylight Time
>
>Kind of makes you wonder about the Nimbus breakup that killed Don Engan and
>the
>other gentleman in Minden.

The "other Gentleman" was Bill Ivans a friend and famous glider pilot. Bill
was a really pioneer of our sport. I have read the NTSB report and it appears
that the Nimbus did have manufacturing errors but nevertheless failed well
above design limits.


Craig Shaber

The NTSB conclude around 55% on the crash that killed Engen. That one
appears to have been pilot error. Inadvertent spin, recovered at 45 deg
nose down, but the pilots appear to have pushed over to (or allowed the
aircraft to rotate) vertical before trying to pull out. If I recall
correctly the outer panels failed at a calculated 55% over certified load...

Co-incidently this was very close to what Schempp had stated the design
was good for.

After a recent fatality some tests were performed in SA - proving that a
cross-controlled entry into a spin from thermalling with a current
flapped 15m racer at full ballast results in an extremely rapid entry,
with a roll over often past the vertical and recovery at VNe even if you
were expecting it. The caption is to be careful out there.

One comment - the NTSB investigators did find some deviations from the
design layup in the wings - although in this instance all of them were
neutral or increased the strength.

Steve Davis wrote:

> At 02:42 18 September 2003, Janus2k wrote:
>
>>John,
>>If you are still wondering about the 4DM breakup, read
>>the NTSB report.
>
>>From reading the report, the plane did not fail.
>
>>Mark
>
> Actually the wings did fail. They presumably failed
> above their design load limit. but they still failed
> in flight causing the crash. A better question would
> be, how much of a design cushion is there between the
> load limit and actual failure of the wing?
>
>
>

Doris and I just returned from another funeral, so I missed some email
messages for a few days.

I spoke with the Schempp-Hirth factory and they tell me they have now
checked a fairly large number of Discus and have found no problems.

In the meantime, the German LBA will issue some kind of directive after a
meeting on September 24th.

The obvious prudent course is to not fly any affected Discus models
specified in the following document until after this meeting:

http://www.lba.de/dokumente/ad/2003-266-e.pdf

Schempp-Hirth owners may want to sign up for my free newsletter at
www.eglider.org as this is the easiest way for me to communicate with
everyone.

Tom Knauff
Knauff & Grove Soaring Supplies
Julian, Pa

Phone 814-355-2483




"Chris OCallaghan" > wrote in message
om...
> It appears that a third S-H aircraft has broken up in flight this
> season. Rather than giving private assurances/explanations to
> individual S-H owners, could someone in-the-know please tell us what
> is going on?

My Discus CS was checked by Wolfgang and Thomas from Shempp-Hirth in Denver
on Friday. A small void was found about 2 feet inboard from the aileron
belcrank inspection cover. It was probed and extended about 3 inches
spanwise and a half inch chordwise. It was repaired.


"Thomas Knauff" > wrote in message
link.net...
> Doris and I just returned from another funeral, so I missed some email
> messages for a few days.
>
> I spoke with the Schempp-Hirth factory and they tell me they have now
> checked a fairly large number of Discus and have found no problems.
>
> In the meantime, the German LBA will issue some kind of directive after a
> meeting on September 24th.
>
> The obvious prudent course is to not fly any affected Discus models
> specified in the following document until after this meeting:
>
> http://www.lba.de/dokumente/ad/2003-266-e.pdf
>
> Schempp-Hirth owners may want to sign up for my free newsletter at
> www.eglider.org as this is the easiest way for me to communicate with
> everyone.
>
> Tom Knauff
> Knauff & Grove Soaring Supplies
> Julian, Pa
>
> Phone 814-355-2483
>
>
>
>
> "Chris OCallaghan" > wrote in message
> om...
> > It appears that a third S-H aircraft has broken up in flight this
> > season. Rather than giving private assurances/explanations to
> > individual S-H owners, could someone in-the-know please tell us what
> > is going on?
>
>

A factor of 1.5 by definition.

--
Bert Willing

ASW20 "TW"


"Steve Davis" > a écrit dans le message
de ...
> At 02:42 18 September 2003, Janus2k wrote:
> >John,
> >If you are still wondering about the 4DM breakup, read
> >the NTSB report.
> >From reading the report, the plane did not fail.
> >
> >Mark
> Actually the wings did fail. They presumably failed
> above their design load limit. but they still failed
> in flight causing the crash. A better question would
> be, how much of a design cushion is there between the
> load limit and actual failure of the wing?
>
>
>