A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Soaring
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

L13 Blanik Mandatory Bulletin



 
 
Thread Tools Display Modes
  #31  
Old June 26th 10, 12:14 AM posted to rec.aviation.soaring
Frank Whiteley
external usenet poster
 
Posts: 1,939
Default L13 Blanik Mandatory Bulletin

On Jun 25, 3:42*pm, JC wrote:
It would be a coincidence but could this be one of the Red Bull
Blaniks? They have Austrian registration and they get flown pretty
hard.
Is there a news article on the accident?

Regards,

Juan Carlos


http://aviation-safety.net/wikibase/wiki.php?id=74748

Link to an image of the glider in hangar on page. Not a Red Bull
Blanik.

Frank Whiteley
Ads
  #32  
Old June 28th 10, 07:27 PM posted to rec.aviation.soaring
Walter[_2_]
external usenet poster
 
Posts: 6
Default L13 Blanik Mandatory Bulletin

Blanik owners and pilots might want to read this call for help from the home
of the Red Bull Blanix team:
http://www.streckenflug.at/popup.php...hilfe.pdf&xy=J

and this question from the author of the above PDF:

Hello,
Does anyone know Detail Information on Blaník which have been modified to
L-13 Type A1, the so called "Llewellyn Modification"?
Even information on the Aeroclub that does this Modification or contact
data, also the name of the Aeroclub would be very helpful for me !

Happy landings and Best Regards!


Walter




  #33  
Old June 29th 10, 12:47 PM posted to rec.aviation.soaring
T8
external usenet poster
 
Posts: 429
Default L13 Blanik Mandatory Bulletin

On Jun 25, 11:41*am, nimbus wrote:
Inspection was done on our Blahnik this afternoon....

Our Blahnik has a low number of flight...ie. only 1200 hours with 1750
starts.
No acrobatics flight except a few rare loopings...

Always aerotowed...No winch launches...

Inspection with eyes and bright light showed nothing. We took pictures
wtih a small digital cam equipped with a flash (small Olympus one).

When we uploaded the pictures on the PC, we carefully looked at the
pictures and we saw ...longs thin cracks...
With the eyes it was impossible to detect due to the fact that the
available room for inspection is very limited....

We spoke in the previous post about fatigue....well, I am deeply
convinced that our Blahnik has never been "fatigued"....
The cracks seems to be produced because the rivet from which the
cracks are born, has been installed by a hand process during the
manufacturing. The manual process for installing these rivets is clear
on the picture I took.
I strongly suspect a poorly manual manufacturing process instead of a
fatigue problem.

I am really upset to discover this problem now especially that there
is no repair procedure nor a replacement procedure.

The AD just states that the Blanik is grounded. This is unacceptable


Would you consider posting those pics somewhere?

- Evan Ludeman / T8
  #34  
Old July 13th 10, 03:39 AM
Ronald Locke Ronald Locke is offline
Junior Member
 
First recorded activity by AviationBanter: Jul 2010
Posts: 4
Default

Quote:
Originally Posted by Ernst View Post
After a fatal accident in Austria LET issued a Mandatory Bulletin:
http://www.let.cz/files/bulletines/M...9a_english.pdf

EASA issued an Emergency Airworthiness Directive:
http://www.caa.co.uk/docs/33/easa_ad_2010_0119_E.pdf
Could anyone advise the current situation in USA, Canada and Europe regarding the grounding of L13 Blaniks ?

Have many been put back into service as a result of satisfactory wing spar inspections, or do most remain grounded due to the fact that the required average usage statistics required by LET cannot be met, and with respect seem most unreasonable.

For instance – what two seater training glider (or for that matter any two seater glider) would have an average of 35% dual and 65% solo usage! More likely, greater than 80% dual would be a more realistic figure I would have thought.
  #35  
Old July 13th 10, 03:18 PM posted to rec.aviation.soaring
Tony[_5_]
external usenet poster
 
Posts: 1,868
Default L13 Blanik Mandatory Bulletin

On Jul 12, 9:39*pm, Ronald Locke Ronald.Locke.
wrote:
Ernst;732355 Wrote:

After a fatal accident in Austria LET issued a Mandatory Bulletin:
http://www.let.cz/files/bulletines/M...9a_english.pdf


EASA issued an Emergency Airworthiness Directive:
http://www.caa.co.uk/docs/33/easa_ad_2010_0119_E.pdf


Could anyone advise the current situation in USA, Canada and Europe
regarding the grounding of L13 Blaniks ?

Have many been put back into service as a result of satisfactory wing
spar inspections, or do most remain grounded due to the fact that the
required average usage statistics required by LET cannot be met, and
with respect seem most unreasonable.

For instance – what two seater training glider (or for that matter any
two seater glider) would have an average of 35% dual and 65% solo usage!
More likely, greater than 80% dual *would be a more realistic figure I
would have thought.

--
Ronald Locke


I haven't heard that the FAA has issued an airworthiness directive
yet, so no L-13's in the USA should be grounded.
  #36  
Old July 13th 10, 05:03 PM posted to rec.aviation.soaring
John Scott[_3_]
external usenet poster
 
Posts: 25
Default L13 Blanik Mandatory Bulletin

Ours was inspected per the bulletinby 2 IAs (concurrently), deemed
airworthy, and signed off. We're flying it.
It had just been down for an annual when the bulletin was released.

John


  #37  
Old July 13th 10, 05:23 PM posted to rec.aviation.soaring
Bob McKellar
external usenet poster
 
Posts: 24
Default L13 Blanik Mandatory Bulletin


"John Scott" wrote in message
.. .
Ours was inspected per the bulletinby 2 IAs (concurrently), deemed
airworthy, and signed off. We're flying it.
It had just been down for an annual when the bulletin was released.

John

Same story for my club, almost.

We pulled the wings and inspected everything and it went fine. Ours is
heading into annual next month, but we didn't want to wait.

Bob McKellar


  #38  
Old July 15th 10, 01:04 AM posted to rec.aviation.soaring
[email protected]
external usenet poster
 
Posts: 106
Default L13 Blanik Mandatory Bulletin


Aluminum, however, does not have the "knee" in the stress/cycle graph
that takes it effectively parallel with the X axis. With aluminum, the
curve heads inexorably towards the X axis.


I see that for some Al alloys and with unnotched coupons, but most all
aircraft metallic structure are notched because of fastener holes. I
am looking at one notched curve now that goes parallel at 10^7
cycles. No glider is going to see the 60-80000 hr life that large
aircraft have proven by service and test. For example, the rewinged
C-5b has an expected service life of 100,000 hrs, validated by fatigue
test. After the test they cut one panel, notched another, and were
unable to get a failure.

Metal structures have been certified with an infinite
fatigue life.


That is almost always true for aircraft certified under the old CAR 3
regulations which did not address fatigue. It is even true for some
aircraft certified under the more modern Part 23 and JAR22
regulations. Unfortunately, the map is not the territory: Just because
the CAA or whoever certified that it is so doesn't mean it is actually
so.


I was referring to among other things, rotor blades cetified in the
70's, that had fatigue, DADT anaylysis and full scale test tests done
with simulated damage.



There is an EXCELLENT, plain language discussion of the design
considerations and fatigue calculations in the Blanik repair and
overhaul manuals published in the mid 70's.


That sounds like valuable material, I would definitely like to read
it. How can I get a copy of that documentation?


I believe the manuals that came with our blanik are available on the
Blanik America site. I think you will find them of great interest,
esp since the EASA AD now is also a US AD as of this Friday.

aerodyne

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Blanik L-23 Super Blanik Manual -F.C.F.S. Joel Flamenbaum Soaring 2 April 14th 10 03:29 PM
Mandatory ELT [email protected] Soaring 9 March 8th 05 03:01 PM
ELT Mandatory ? Jim Culp Soaring 20 June 19th 04 06:40 PM
New security bulletin gatt Piloting 28 June 9th 04 10:33 PM
Grob 103 bulletin becomes AD Mike Borgelt Soaring 0 October 3rd 03 12:47 AM


All times are GMT +1. The time now is 05:49 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright ©2004-2019 AviationBanter.
The comments are property of their posters.