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Thomas Knauff
August 4th 03, 08:17 PM
Schempp-Hirth has issued a tech note 396-8 for Duo Discus serial numbers 165
through 389, and Duo Discus T serial numbers 1 through 78.

These Duo Discus must not be flown until the inspection and repair (if
necessary) is accomplished.

Further details of these tech notes can be found on their web site.

http://www.schempp-hirth.com

or, we can email you copies of the tech note.

Essentially, the bond between the spar and skin of the glider must be
inspected for voids.

The inspection will take 3 to 5 hours.

We are contacting USA repair shops to find out if they have the necessary
tools for the inspection and repair. Please call or email us with your
questions.

Tom Knauff
Knauff & Grove Soaring Supplies
(814) 355 2483
fax (814) 355 2633

Paul
August 5th 03, 12:28 AM
"John Galloway" > wrote in message
...
> At 20:00 04 August 2003, Thomas Knauff wrote:
> >>
> >Essentially, the bond between the spar and skin of
> >the glider must be
> >inspected for voids.
> >
>
> Mr Knauff,
>
> I believe this is not entirely accurate.

Splitting hairs over the wording is not going to change the fact that 300
odd Duo Discus are grounded until they have had holes drilled in their wings
and inspected.
Paul

Thomas Knauff
August 5th 03, 02:07 AM
Sorry for the error.
Doris and I just returned from a pleasant week at Oshkosh this morning and
faced this and nearly a thousand emails (almost half junk) to deal with.

It looks like we have things well in hand with the problem in the USA.

"John Galloway" > wrote in message
...
> At 20:00 04 August 2003, Thomas Knauff wrote:
> >>
> >Essentially, the bond between the spar and skin of
> >the glider must be
> >inspected for voids.
> >
>
> Mr Knauff,
>
> I believe this is not entirely accurate. The Technical
> Note says that the Duo involved in the incident had
> 'a failure in the bonding of the spar cap and the spar
> web'. Furthermore the 'Actions' required by the technical
> note include:
>
> '1. The bonding between the upper spar cap and the
> spar web are to be checked according to the instructions
> in the appendix of this Technical Note.'
>
> +
>
> '2. Defects in the spar cap and spar web bonding are
> to be repaired according to the instructions in the
> appendix to this Technical Note.'
>
> For those who are interested, the drawing at the bottom
> of page 3 of the Appendix shows the spar construction
> and the photograph on page 8 shows the defect between
> an attachment flange of the spar web and the carbon
> fibre spar cap quite clearly.
>
> John Galloway
>
>
>

Mark Zivley
August 5th 03, 02:16 AM
Changing the subject just a tad. It's obvious that if one can locate a
boroscope or similar device with a roughly 25 foot reach that it may be
possible to inspect the vast majority of the wing from a single well
placed hole. Those who have begun this process may be able to comment.

Furthermore, if anyone finds a solution which approaches the above
described level of elegance, please do NOT hesitate to post as much
information as possible so that the others may benefit. i.e. make and
model of the boroscope. Any particulars as to technique used for
reaching the necessary corners inside the wing. If there are any issues
with focal distance, etc.



Paul wrote:
> "John Galloway" > wrote in message
> ...
>
>>At 20:00 04 August 2003, Thomas Knauff wrote:
>>
>>>Essentially, the bond between the spar and skin of
>>>the glider must be
>>>inspected for voids.
>>>
>>
>>Mr Knauff,
>>
>>I believe this is not entirely accurate.
>
>
> Splitting hairs over the wording is not going to change the fact that 300
> odd Duo Discus are grounded until they have had holes drilled in their wings
> and inspected.
> Paul
>
>
>

Paul
August 5th 03, 03:36 AM
"Mark Zivley" > wrote in message
...
> Changing the subject just a tad. It's obvious that if one can locate a
> boroscope or similar device with a roughly 25 foot reach that it may be
> possible to inspect the vast majority of the wing from a single well
> placed hole. Those who have begun this process may be able to comment.

Not sure what the FAA would do but our New Zealand CAA would require an AMOC
to be completed and OK'd before the inspection could be changed from that of
the Techicnal Note or AD and a 25 ft long boroscope would not be lying
around most workshops. The Manufacturers has stated the inspection to be
carried out and that stands. The holes drilled can be taped up if they are
small enough . ( according to the TN note) Becomes academic if the web needs
repairing I guess.
Paul

Caracole
August 5th 03, 04:52 AM
> Schempp-Hirth has issued a tech note 396-8 for Duo Discus serial numbers 165
> through 389, and Duo Discus T serial numbers 1 through 78.
>
> These Duo Discus must not be flown until the inspection and repair (if
> necessary) is accomplished.
>
> Tom Knauff

Neither the LBA nor the manufacturer has the authority to ground
gliders operating with
U.S. Standard Airwothiness Certificates. As of today, the FAA has not
issued an
AD requiring compliance with the Spar inspection technical note issued
by
Schempp-Hirth on the Duo Discus. There is every likelihood that the
FAA
will issue an AD regarding this.

However the factory's own web page states that,
"For security reasons a larger number of Duo Discus and Duo Discus T
have been grounded, as the exact serial numbers of potentially
affected gliders could not be determined in the short time given."

We may find that the FAA pushes the factory to determine the exact
serial numbers of potentially affected gliders, so that a more
accurate set of glider serial numbers can be included in any U.S. AD.

So for now at least, for U.S. owners, compliance with the inspection
is at their own discretion.

Interestingly, someone said to me the other day that if the potential
for faulty construction goes back at least 5 years with the DUO and it
includes CS DUOs manufactured in a different country, maybe the LBA
should consider requiring inspections on other Schempp-Hirth models as
well?

I would think that the factory would at least put up a page on their
Web site so that the DUO owners can see what the statistical results
of the inspections are as this debacle unfolds.

In the meantime, maybe the DUO owners can post to the news group with
the results of their gliders inspection and the degree of repairs
required. I'm sure the DUO owners would greatly appreciate the
information.

M Eiler

Bruce Greeff
August 5th 03, 07:37 AM
While it is correct that only the local Aviation Authority has the power
to ground aircraft it would be extremely unwise to ignore a safety
warning from the manufacturer.

The tech note and advice from Schemmp Hirth was correctly represented -
the factory say these aircraft must not be flown until inspected. If you
are affected by a factory defect, you might get some credit when it
comes to repair. If you (or your bereaved spouse) are the proud owner of
a pile of composite confetti, you may find the factory and your
insurance company less helpful.

Bert Willing
August 5th 03, 08:02 AM
Legally quite true, I guess.

However, if a manufacturer comes forward and says that serial no's x to y
are potentially not airworthy, common sense requires those aircrafts to be
grounded even if local authorities are not up to the news.

--
Bert Willing

ASW20 "TW"


"Caracole" > a écrit dans le message de
om...
> > Schempp-Hirth has issued a tech note 396-8 for Duo Discus serial numbers
165
> > through 389, and Duo Discus T serial numbers 1 through 78.
> >
> > These Duo Discus must not be flown until the inspection and repair (if
> > necessary) is accomplished.
> >
> > Tom Knauff
>
> Neither the LBA nor the manufacturer has the authority to ground
> gliders operating with
> U.S. Standard Airwothiness Certificates. As of today, the FAA has not
> issued an
> AD requiring compliance with the Spar inspection technical note issued
> by
> Schempp-Hirth on the Duo Discus. There is every likelihood that the
> FAA
> will issue an AD regarding this.
>
> However the factory's own web page states that,
> "For security reasons a larger number of Duo Discus and Duo Discus T
> have been grounded, as the exact serial numbers of potentially
> affected gliders could not be determined in the short time given."
>
> We may find that the FAA pushes the factory to determine the exact
> serial numbers of potentially affected gliders, so that a more
> accurate set of glider serial numbers can be included in any U.S. AD.
>
> So for now at least, for U.S. owners, compliance with the inspection
> is at their own discretion.
>
> Interestingly, someone said to me the other day that if the potential
> for faulty construction goes back at least 5 years with the DUO and it
> includes CS DUOs manufactured in a different country, maybe the LBA
> should consider requiring inspections on other Schempp-Hirth models as
> well?
>
> I would think that the factory would at least put up a page on their
> Web site so that the DUO owners can see what the statistical results
> of the inspections are as this debacle unfolds.
>
> In the meantime, maybe the DUO owners can post to the news group with
> the results of their gliders inspection and the degree of repairs
> required. I'm sure the DUO owners would greatly appreciate the
> information.
>
> M Eiler

Mark Stevens
August 5th 03, 12:07 PM
And of course although quick, a posting on RAS or an
update on a manufacturers web site does not mean that
everyone affected will find out...


At 07:42 05 August 2003, Bert Willing wrote:
>Legally quite true, I guess.
>
>However, if a manufacturer comes forward and says that
>serial no's x to y
>are potentially not airworthy, common sense requires
>those aircrafts to be
>grounded even if local authorities are not up to the
>news.
>
>--
>Bert Willing
>
>ASW20 'TW'
>
>
>'Caracole' a écrit dans le message de
om...
>> > Schempp-Hirth has issued a tech note 396-8 for Duo
>>>Discus serial numbers
>165
>> > through 389, and Duo Discus T serial numbers 1 through
>>>78.
>> >
>> > These Duo Discus must not be flown until the inspection
>>>and repair (if
>> > necessary) is accomplished.
>> >
>> > Tom Knauff
>>
>> Neither the LBA nor the manufacturer has the authority
>>to ground
>> gliders operating with
>> U.S. Standard Airwothiness Certificates. As of today,
>>the FAA has not
>> issued an
>> AD requiring compliance with the Spar inspection technical
>>note issued
>> by
>> Schempp-Hirth on the Duo Discus. There is every likelihood
>>that the
>> FAA
>> will issue an AD regarding this.
>>
>> However the factory's own web page states that,
>> 'For security reasons a larger number of Duo Discus
>>and Duo Discus T
>> have been grounded, as the exact serial numbers of
>>potentially
>> affected gliders could not be determined in the short
>>time given.'
>>
>> We may find that the FAA pushes the factory to determine
>>the exact
>> serial numbers of potentially affected gliders, so
>>that a more
>> accurate set of glider serial numbers can be included
>>in any U.S. AD.
>>
>> So for now at least, for U.S. owners, compliance with
>>the inspection
>> is at their own discretion.
>>
>> Interestingly, someone said to me the other day that
>>if the potential
>> for faulty construction goes back at least 5 years
>>with the DUO and it
>> includes CS DUOs manufactured in a different country,
>> maybe the LBA
>> should consider requiring inspections on other Schempp-Hirth
>>models as
>> well?
>>
>> I would think that the factory would at least put
>>up a page on their
>> Web site so that the DUO owners can see what the statistical
>>results
>> of the inspections are as this debacle unfolds.
>>
>> In the meantime, maybe the DUO owners can post to
>>the news group with
>> the results of their gliders inspection and the degree
>>of repairs
>> required. I'm sure the DUO owners would greatly appreciate
>>the
>> information.
>>
>> M Eiler
>
>
>

Mark Zivley
August 5th 03, 02:26 PM
That would be very unfortunate. It's pretty clear that SH has provided
suitable places to drill holes on the premise that whatever boroscope
used is fairly short. Clearly, the underlying objective is to make sure
that the entire length of the upper spar flange (aft side) is visually
inspected for any areas which didn't get enough resin and therefore
might not be adequately bonded. If you can do that with a 25-30' long
boroscope then you'd be complying with the intent of the tech note. If
you call around to some companies specializing in NDT or perhaps who do
boiler tube inspections, etc. you may find a suitable scope.

Paul wrote:
> "Mark Zivley" > wrote in message
> ...
>
>>Changing the subject just a tad. It's obvious that if one can locate a
>>boroscope or similar device with a roughly 25 foot reach that it may be
>>possible to inspect the vast majority of the wing from a single well
>>placed hole. Those who have begun this process may be able to comment.
>
>
> Not sure what the FAA would do but our New Zealand CAA would require an AMOC
> to be completed and OK'd before the inspection could be changed from that of
> the Techicnal Note or AD and a 25 ft long boroscope would not be lying
> around most workshops. The Manufacturers has stated the inspection to be
> carried out and that stands. The holes drilled can be taped up if they are
> small enough . ( according to the TN note) Becomes academic if the web needs
> repairing I guess.
> Paul
>
>

Bill Daniels
August 5th 03, 03:14 PM
"Mark Zivley" > wrote in message
...
> That would be very unfortunate. It's pretty clear that SH has provided
> suitable places to drill holes on the premise that whatever boroscope
> used is fairly short. Clearly, the underlying objective is to make sure
> that the entire length of the upper spar flange (aft side) is visually
> inspected for any areas which didn't get enough resin and therefore
> might not be adequately bonded. If you can do that with a 25-30' long
> boroscope then you'd be complying with the intent of the tech note. If
> you call around to some companies specializing in NDT or perhaps who do
> boiler tube inspections, etc. you may find a suitable scope.
>

It might be possible for a clever person to assemble a makeshift borescope
with a "lipstick" TV camera fitted with a close-up lens and an ultra-bright
LED for illumination. Just tape the camera to the end of a length of PVC
water pipe and insert it into the wing through the root. The wires for the
camera and LED would be neatly routed through the pipe. Wireless cameras
might work too.

I've used tiny CCTV cameras for the internal inspection of engines.

Bill Daniels

Bob Mowry
August 5th 03, 03:33 PM
Anyone see a first person account of the accident? It sounds like it
might be some good reading. I wonder exactly how the pilots were able
to regain control after the failure?

I'm assuming the accident occurred in Germany. Is there a German
equivalent to www.ntsb.gov where we can read about the accident
report?

-bob

John Galloway
August 5th 03, 04:00 PM
I spoke to a friend and Duo owner today who visited
Southern Sailplanes (the UK agents and repairers) yesterday
where 3 Duos were examined using a small video camera
on a long pole. Apparently the inspections could be
done in 'about 10 minutes' per wing without inspection
holes being drilled in the wing skins.

He tells me that 2 Duos passed and one newish Duo failed.

John Galloway

W.J. \(Bill\) Dean \(U.K.\).
August 5th 03, 04:18 PM
If you go to the Shempp-Hirth web-site and look at the actual document:
Schempp-Hirth - Appendix to Technical Note No. 396-8/No. 890-3,
http://www.schempp-hirth.com/tmdocs/396-8-489.pdf
and look at page 2, it says:
"REMARK:
If a very long endoscope is available, which enables a safe check of the
bonding, fewer inspection openings (see item 2) may be required."

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.

>
> "Mark Zivley" > wrote in message
> ...
>
> Changing the subject just a tad. It's obvious that if one can locate a
> boroscope or similar device with a roughly 25 foot reach that it may be
> possible to inspect the vast majority of the wing from a single well
> placed hole. Those who have begun this process may be able to comment.
>
> Furthermore, if anyone finds a solution which approaches the above
> described level of elegance, please do NOT hesitate to post as much
> information as possible so that the others may benefit. i.e. make and
> model of the boroscope. Any particulars as to technique used for
> reaching the necessary corners inside the wing. If there are any issues
> with focal distance, etc.
>

Marc Ramsey
August 5th 03, 04:24 PM
"Mark Stevens" > wrote...
> And of course although quick, a posting on RAS or an
> update on a manufacturers web site does not mean that
> everyone affected will find out...

You shouldn't assume those were the only ways those affected were notified. I
received a phone call from Rex Mayes at Williams Soaring Center a full 24 hours
before anything appeared on RAS or the web site. Schempp-Hirth apparently asked
him to contact all Duo owners on the west coast of the US.

BTW, Rex now has an endoscope, and is in the midst of his first inspection...

Marc

Markus Feyerabend
August 5th 03, 05:22 PM
Hi Bob,that would be www.bfu-web.de, which is the web page
of the 'investigation office for aviation in/accidents'
in germany. But don´t expect any up-to-date information
there, in that respect it is not comparable to the
NTSB web page...Best regards,MarkusAt 15:12 05 August 2003, Bob Mowry wrote:>Anyone see a first person account of the accident?
> It sounds like it>might be some good reading. I wonder exactly how the
>pilots were able>to regain control after the failure?>>I'm assuming the accident occurred in Germany. Is
>there a German>equivalent to www.ntsb.gov where we can read about
>the accident>report?>>-bob>

Judy Ruprecht
August 5th 03, 05:25 PM
SSA's contact at the FAA's Small Airplane Directorate
reports receiving copies of the Duo Discus TN and German-issued
AD yesterday. These documents and further information
requested of LBA/Schempp Hirth will be reviewed prior
to issuance of a US AD. No estimate on when a US AD
may be issued, but an 'airworthiness concern sheet'
(preliminary to actual AD issuance) is expected this
week.

In terms of what lies ahead, please note that when
a US AD is issued on the basis of a foreign country's
findings, it often adopts the same inspection procedures
and remedies. (So owners who comply with the LBA-issued
AD now stand a good chance of being in compliance with
the US AD whenever it is issued.)

Judy

Mark Stevens
August 5th 03, 07:18 PM
Marc,

Well put, but not my meaning.. I was not suggesting
that RAS etc were the only ways, just that some people
who owned and operated Duos might not have access,
and that by implication it was important for the formal
channels to operate as well..

Mark

At 16:00 05 August 2003, Marc Ramsey wrote:
>'Mark Stevens' wrote...
>> And of course although quick, a posting on RAS or
>>an
>> update on a manufacturers web site does not mean that
>> everyone affected will find out...
>
>You shouldn't assume those were the only ways those
>affected were notified. I
>received a phone call from Rex Mayes at Williams Soaring
>Center a full 24 hours
>before anything appeared on RAS or the web site. Schempp-Hirth
>apparently asked
>him to contact all Duo owners on the west coast of
>the US.
>
>BTW, Rex now has an endoscope, and is in the midst
>of his first inspection...
>
>Marc
>
>
>

Mark Zivley
August 5th 03, 09:51 PM
Bill,

Actually, for $80 U.S. you can get a black and white camera and for $170
you can get color. Just checked what they had at a local electonics
store during lunch and the lens is adjustable to fit the distances that
we'd see in this situation.

Mark

Bill Daniels wrote:
> "Mark Zivley" > wrote in message
> ...
>
>>That would be very unfortunate. It's pretty clear that SH has provided
>>suitable places to drill holes on the premise that whatever boroscope
>>used is fairly short. Clearly, the underlying objective is to make sure
>>that the entire length of the upper spar flange (aft side) is visually
>>inspected for any areas which didn't get enough resin and therefore
>>might not be adequately bonded. If you can do that with a 25-30' long
>>boroscope then you'd be complying with the intent of the tech note. If
>>you call around to some companies specializing in NDT or perhaps who do
>>boiler tube inspections, etc. you may find a suitable scope.
>>
>
>
> It might be possible for a clever person to assemble a makeshift borescope
> with a "lipstick" TV camera fitted with a close-up lens and an ultra-bright
> LED for illumination. Just tape the camera to the end of a length of PVC
> water pipe and insert it into the wing through the root. The wires for the
> camera and LED would be neatly routed through the pipe. Wireless cameras
> might work too.
>
> I've used tiny CCTV cameras for the internal inspection of engines.
>
> Bill Daniels
>

Mark Navarre
August 6th 03, 05:00 AM
http://www.mars-cam.com/cameras/bullet_cameras/v2214.htm
-
Mark Navarre
ASW-20 OD
California, USA
-

ventus2ct (Ruud Holswilder)
August 6th 03, 12:48 PM
On 5 Aug 2003 19:52:19 GMT, Al Eddie
> wrote:

>At 15:12 05 August 2003, Bob Mowry wrote:
>>Anyone see a first person account of the accident?
>> It sounds like it
>>might be some good reading. I wonder exactly how the
>>pilots were able
>>to regain control after the failure?
>>
>
>They didn't. They jumped...!
>
Wrong!
They were able to regain some control and fly the glider over
inhabited terrain.
Than they made the choice to jump.

Bob Mowry
August 6th 03, 04:06 PM
Al Eddie > wrote in message >...
> They didn't. They jumped...!
>
> ;-)

"Due to quick-wittedness of the pilots, the glider stayed maneuverable
for another couple of minutes, which enabled them to evacuate the
airplane over an unpopulated area."

This is the part of the notice I was referring to. Perhaps they were
able to use their full underwear as outboard ballast on the shortened
wing :)

-bob

John Giddy
August 7th 03, 12:32 AM
"Bob Mowry" > wrote in message
om...
| Al Eddie > wrote in
message >...
| > They didn't. They jumped...!
| >
| > ;-)
|
| "Due to quick-wittedness of the pilots, the glider stayed
maneuverable
| for another couple of minutes, which enabled them to
evacuate the
| airplane over an unpopulated area."
|
| This is the part of the notice I was referring to.
Perhaps they were
| able to use their full underwear as outboard ballast on
the shortened
| wing :)

No, Bob,
On the longer wing ! Think about it...
Cheers, John G.

W.J. \(Bill\) Dean \(U.K.\).
August 7th 03, 12:28 PM
I understand that the Duo Discus owned by The Soaring Centre, Husbands
Bosworth has been inspected by Southern Sailplanes (the U.K. Schempp-Hirth
agent) and is back at the club, ready to be flown.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.

>
> "Thomas Knauff" > wrote in message
> thlink.net...
>
> Schempp-Hirth has issued a tech note 396-8 for Duo Discus serial numbers
> 165 through 389, and Duo Discus T serial numbers 1 through 78.
>
> These Duo Discus must not be flown until the inspection and repair (if
> necessary) is accomplished.
>
> Further details of these tech notes can be found on their web site.
>
> http://www.schempp-hirth.com
>
> or, we can email you copies of the tech note.
>
> Essentially, the bond between the spar and skin of the glider must be
> inspected for voids.
>
> The inspection will take 3 to 5 hours.
>
> We are contacting USA repair shops to find out if they have the necessary
> tools for the inspection and repair. Please call or email us with your
> questions.
>
> Tom Knauff
> Knauff & Grove Soaring Supplies
> (814) 355 2483
> fax (814) 355 2633
>

Mark Zivley
August 8th 03, 02:40 AM
Today I visited a local Everest VIT office and looked at their video
scope for potential use in examining our wings. It's available in a 25'
length, the scope has a 8.4mm diameter and the tip can articulate if
needed. A 90 degree side viewing tip attachment is available.

http://www.everestvit.com/v_borescopes/xlpro.html

I plan on renting one of these next week to do our plane and put this
out on the NG in case there are people still looking for viable options
with minimal drilling.

The scope can output to a VCR and can also do .JPG still captures.

Fingers crossed for good bonding....

Mark

FWIW both Southwest Airlines and Continental Airlines maintenance groups
were very pleasantly willing to offer suggestions which led to this contact.

Thomas Knauff
August 9th 03, 10:10 PM
I have posted the easy inspection procedures using an inexpensive video
camera on my newsletter. No holes need drilled. It is easy.

If you are not subscribed, you can sign up free at www.eglider.org.

If you need instructions emailed, or faxed to you, Please send me an email.


> Tom Knauff
> Knauff & Grove Soaring Supplies
> (814) 355 2483
> fax (814) 355 2633

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