DG-300/303 owners...

On Apr 7, 2:34 am, Marc Ramsey wrote:
You should take a look at this:

http://www.dg-flugzeugbau.de/holm-dg300-e.html

Marc

I tried to read the computer translation out of curiosity, it is
dreadful.
To encapsulate:
Most, if not all DG 300 are restricted to a much lower speed and load
envelope due to flaws found in the spar production.
The fibers in the spar caps are not strait or aligned due to
manufactured flaws in the root area, hence the compression strength is
reduced.
The gliders will be able to fly with a reduce flight envelope.
Not fix is possible due to cost.
In a nut shell the value of that glider is substantially reduced.

Udo

The Company ELAN from Slovenia, which produced for Glaser Dirks GmbH
changed the production process without permission of Wilhelm Dirks at an
unknown date. This means that nobody knows which gliders are affected.

Andreas

http://www.dg-flugzeugbau.de/holm-dg300-e.html

My German skills are non-existant. Can anyone tell me if the lengthier
German part mentions which serial numbers are affected, because the English
part says the manufacturing error began sometime during the production run.
Presumably that means some of the early DG-300's were built right.

Thanks,
Bullwinkle

On 7 Apr 2007 10:59:27 -0700, wrote:

I, for one, bought a DG-300 for its superior strength among other
reasons. We will have to wait for more clarification from DG but at
this point it seems that strength has now been reduced. Since this is
admittedly the fault of ELAN for not following the correct
manufacturing process and not notifying DG that they were altering the
manufacturing process this seems like a negligence issue. I would
hope they would do something to rectify the situation.


DG decided this:
- NO inspection required

If you decide not to perform an inspection, these new limits will
become valid for a DG-300/DG-303 Acro:

- Vne limited from 270 kp/h to 250 kp/h
- Va limited from 200 to 175 kp/h
- Maximum T/O weight limited from 525 to 450 kg
- 6 kg lower limit of mass of non-carrying structure
- aerobatics prohibited

Apart from the max T/O weight (and the prohibition of aerobatics for
the DG-303 Acro) none of this limitations is going to have any
practical influence on aircraft handling, don't you agree?




Bye
Andreas

Ok guys,

I did a bit of research on the issue. Here the key points from DG's
posting with some additional information about DG's and Elan's
history. For those who wonder, I'm a native German speaker :-) :

The issue:
- Elan, who has been producing all DG 300/303 since its launch (up it
being taken over by AMS-Flight in 1999), apparently changed the
production process of the main spar at some unknown point in the past
without Glaser-Dirks (the DG predecessor) approval leading to the
possibility of faulty main spars (not all main spars produced by them
are necessary faulty).
- The glider that initially revealed the faulty main spar as a result
of a servere landing accident is about 20 years old with aprox. 1500h.
- There are about 500 DG-300/303 gliders still flying with an average
age of about 15 years and a total of about 1 million hours.
- No DG 300/303 has ever had a failed wing in flight as a result of
structural failure.
- The required breaking strength of the wing at the time of
certification was 1.725 times the max allowed in flight-load. The
actual certification test to failure was stopped at 2.1 times the max
allowed in-flight load without the wing failing.
- DG does not now how many gliders are affected, out of 8 tested 3 had
a faulty main spar.
- To test the wing is difficult and expensive, the wing has to be cut
open.

Possible solutions:
1. All gliders will be grounded
2. All gliders will have to be inspected within a reasonable time
period and repaired if necessary. The inspection would cost around EUR
6000 per glider, a repair, if necessary can easily reach EUR 5000. All
gliders would have to come to DG's factory in Germany since it would
be near impossible to develop guidelines about what is still
acceptable and what has to be repaired.
3. DG tries, using calculations, tests to failure and load tests on
faulty main spars, to prove that even faulty main spars have enough
strength as a result of the very high structural reserves of the
original design. This approach might allow to continue operating the
glider with reduced operating limits without the need for inspections
and repairs.

DG decided to go the 3. route to avoid having to ground all gliders
and has spent to date about EUR 10,000 to do the required testing.
Based on the suprisingly good results when testing the faulty main
spars they got the following operating limitations approved by the
EASA (European FAA equivalent):

New Operating Limits for all DG-300/303:
- Max speed reduced from 270 km/h to 250 km/h
- Maneuvering speed reduced from 200 km/h to 175 km/h
- MTOW reduced from 525 kg to 450 kg
- No aerobatics (also applies to the DG-300 Acro)

If you want to avoid these limitations you will have to get the glider
inspected and repaired if necessary.

The liability/legal issues/responsability:
The great majority of the affected gliders were delivered by & paid to
Glaser-Dirks which went bankrupt in 1996. The current DG-Flugzeugbau
only took over the Type Certificates and spare part supply but not the
product liability, the actual gliders and faulty main spars were not
manufactured by Glaser-Dirks but by Elan which does not dispute this.

Elan refuses to shoulder any costs related to the investigation of the
faulty main spars and does not respond to any inquiries. All gliders
with faulty main spars produced by Elan are out of warranty.

About 10 gliders were produced by Elan or its successor AMS-Flight and
delivered by the current DG-Flugzeugbau, all these gliders are out of
warranty as well.

AMS-Flight was established in 1999 to continue Elan's existing
aircraft production and took over the entire Elan Flight Division of
Elan as of Sep. 1st, 1999. AMS produced and delivered about 25 gliders
under their own responsibility and claims, that they converted the
production process back to the original specifications. However, they
don't seem to be able to state when and starting with which serial
number they did so. It is likely that the only DG-303s that are still
under warranty are technically ok but nobody knows for sure and only
an inspection will be able to prove that.


Here the companies' time lines & current sales:
1973 - Glaser-Dirks Flugzeugbau GmbH founded, prudction of the DG-100
begins
1978 - Elan founded
1983 - DG-300 introduced and produced by Elan
1996 - Glaser-Dirks Flugzeugbau GmbH goes bankrupt - DG Flugzeugbau
GmbH buys up key parts of Glaser-Dirks (excluding the product
liability of the DG-300 series), Elan continues to produce the
DG-300/303.
1999 - AMS-Flight established to continue Elan's existing aircraft
production, takes over the entire Elan Flight Division of Elan as of
Sep. 1st, 1999.
2006 - AMS-Flight stops DG-303 ELAN manufacturing. As of February 2006
444 DG-300 ELAN & 67 DG-303 ELAN gliders were produced.
2006 - AMS sales EUR 2.4 million (projected), 40 employees
2006 - DG sales EUR 7 million (delivered 50 planes), 75 Employees


The potential costs of fixing all affected DG-300/303 gliders
Inspection: 500 gliders in service x EUR 6000 per inspection = EUR
3,000,000
Repairs: 188 gliders (3 out of 8) x EUR 5000 per repair = EUR
940,000

Total (without any related costs): EUR 3,940,000 (approx. USD
5,265,000)

Looking at that total you can see that this could potentially bankrupt
either company (with related loss of employment), hence DG's close
look at their legal responibility...

I'm not taking any sides on this, look at above facts and judge for
yourself. Either way there will only be losers in this messy affair...

Markus

Hi guys,

John Giddy pointed out an important restriction I left out in my
summary above (not sure how I missed that, sorry
about that):

- Maximum mass of non-lifting parts is reduced from 246 kg (542 lb) to
240 kg (529 lb)

So the complete set of new restrictions to the operational limits is
as follows:

- Max speed reduced from 270 km/h (146 kt) to 250 km/h (135 kt)
- Maneuvering speed reduced from 200 km/h (108 kt) to 175 km/h (94 kt)
- MTOW reduced from 525 kg (1157 lb) to 450 kg (992 lb)
- Maximum mass of non-lifting parts reduced from 246 kg (542 lb) to
240 kg (529 lb)
- No aerobatics (also applies to the DG-300 Acro)

DG's definition of non-lifting parts is as follows:

- Fuselage (with permanently installed equipment, canopy, and main
pins)
- Cockpit load (Pilot + parachute + equipment for instance tail fin
battery in baggage compartment instead of in tail fin)
- Horizontal tail

This means that your max. cockpit load is reduced by 6 kg (13 lb) all
other things being equal.

I just saw that DG apparently just posted the complete English
translation of their German posting:

http://www.dg-flugzeugbau.de/holm-dg300-e.html

I hope this helps,

Markus

DG... has spent to date about EUR 10,000 to do the required testing.

Are we supposed to be impressed that DG spends this on the fleet?
That is less than it would cost to ship, inspect and repair a single
US-based glider!

On Apr 9, 9:22 am, "Mike Yankee" wrote:
DG... has spent to date about EUR 10,000 to do the required testing.

Are we supposed to be impressed that DG spends this on the fleet?
That is less than it would cost to ship, inspect and repair a single
US-based glider!

A quick clarification to my original cost translation after carefully
re-reading the original German post:

The inspection is estimated at EUR 6000 per glider. If a repair is
deemed necessary it can easily reach EUR 5000 PER MAIN SPAR. Since a
glider has 2 wings with 2 spars we'd end up with a worst case scenario
of EUR 16000 per glider and a potential total of some 376 main spars
affected in a fleet of some 500 gliders (initial test showed 3 out of
8 main spars defective).

So the potential total costs for the entire fleet would be:

- Inspection: 500 gliders in service x EUR 6000 per
inspection = EUR 3,000,000
- Repairs: 376 main spars (3 out of 8) x EUR 5000 per
repair = EUR 1,880,000
- Total (without any related costs) = EUR 4,940,000
(approx. USD 6,521,000)

Also note that DG's owner apparently just added some comments below
the original posting related to the considerable discussion going on
especially in German forums.

The extended DG posting: http://www.dg-flugzeugbau.de/holm-dg300-e.html

For those of you who know some German here a link to the discussion on
one of the main forums:
http://www.segelflug.de/cgi-bin/wwwt...oard=Flugzeuge

The pictures DG's owner (Friedel Weber) refers to in his comments can
be found he

http://www.segelflug.de/cgi-bin/wwwt...5&o=#Post65186

Markus

Markus Graeber wrote:
On Apr 9, 9:22 am, "Mike Yankee" wrote:
DG... has spent to date about EUR 10,000 to do the required testing.
Are we supposed to be impressed that DG spends this on the fleet?
That is less than it would cost to ship, inspect and repair a single
US-based glider!

A quick clarification to my original cost translation after carefully
re-reading the original German post:

The inspection is estimated at EUR 6000 per glider. If a repair is
deemed necessary it can easily reach EUR 5000 PER MAIN SPAR. Since a
glider has 2 wings with 2 spars we'd end up with a worst case scenario
of EUR 16000 per glider and a potential total of some 376 main spars
affected in a fleet of some 500 gliders (initial test showed 3 out of
8 main spars defective).

3 of 8 in a sample that size (8) is playing pretty fairly free and loose
with statistics. Did DG sample gliders they thought would be affected
or did they sample across the entire manufacturing run? The numbers
could be much different.
Also, since they say they've tested 8 gliders, it costs EUR 6000/glider
to test, and they've spent EUR 10,000, I'm assuming they've only tested
wrecked gliders. That, or they hired an accountant from Enron. ;-)




Shawn

On Apr 9, 11:52 am, Shawn wrote:

3 of 8 in a sample that size (8) is playing pretty fairly free and loose
with statistics. Did DG sample gliders they thought would be affected
or did they sample across the entire manufacturing run? The numbers
could be much different.
Also, since they say they've tested 8 gliders, it costs EUR 6000/glider
to test, and they've spent EUR 10,000, I'm assuming they've only tested
wrecked gliders. That, or they hired an accountant from Enron. ;-)

Shawn

8 samples implies that they tested 4 gliders including the one that
showed the original defect after a severe landing accident. From what
I understand that original glider was repaired and is airworthy again
(and for sale by the club in Germany that owns it), it probably is the
only one right now with a guarantee that it has no main spar defects
and as such can be operated within the old operating limits...

I would guess they tested whatever they had at hand and of course the
sample might not be representative but all you can go by right now to
get an idea of the extend of the problem; especially since Elan is not
able/willing to provide any more information as to when they did the
change to the wing manufacturing process which can possibly lead to
the main spar defects discovered.

I assume the EUR 10,000 mentioned is the cost of the load test & tests
to destruction they did on affected wings to establish the new
operating limitations.

Markus

Instead of being absolutely straight, the rovings of one spar cap
showed a slightly wave-like pattern. Alarmed by this discovery we
investigated the spar caps of several other DG-300 wings, which were
in for repair in our factory or other approved maintenance shops. We
found a similar, but less severe pattern at some of these wings too.

The most important question right to the beginning:
"Why may DG-300 spars exhibit this wave-like pattern, and is this flaw
also possible at spars of other DG airplanes?"

The answer:
This specific flaw is limited to the DG-300/303 series!
For all DG wings, except for the DG-300 and DG-600, the spar caps are
manufactured in separate a mould, which allows maximum precision for
the roving placement. While the rovings for the DG-600 are placed
directly into the wing mould, they are inserted into a prefabricated
channel which becomes an integral part of the wing structure. This
allows the same precision for the roving placement. Only the
DG-300/303 uses a different manufacturing method (which is also used
by other manufacturers), therefore only the DG-300/303 is prone to the
described manufacturing flaw.


Notice the statement (which is also used by other manufacturers)