New Blanik AD

[Eric Munk]

To whom it may concern,

EASA has just published a new AD: EASA AD 2010-0185-E.

It grounds all Blaniks with immediate effect, including L-13, L-13A and
all aircraft that passed earlier AD inspections. Reason is that the failed
wing spar on the Austrian accident glider failed before reaching its
theoretical lifetime, and it failed due to fatigue.

Grounding is pending development of terminating action, which I imagine
will take considerable time, and expense...

Sorry to be the bearer of bad news...

Eric Munk
The Netherlands

[BTiz]

On Sep 6, 1:49*am, Eric Munk > wrote:
> To whom it may concern,
>
> EASA has just published a new AD: EASA AD 2010-0185-E.
>
> It grounds all Blaniks with immediate effect, including L-13, L-13A and
> all aircraft that passed earlier AD inspections. Reason is that the failed
> wing spar on the Austrian accident glider failed before reaching its
> theoretical lifetime, and it failed due to fatigue.
>
> Grounding is pending development of terminating action, which I imagine
> will take considerable time, and expense...
>
> Sorry to be the bearer of bad news...
>
> Eric Munk
> The Netherlands

It will be interesting how the US FAA handles this one.
Anyone have a link to the EASA AD?

[mattm[_2_]]

On Sep 6, 4:49*am, Eric Munk > wrote:
> To whom it may concern,
>
> EASA has just published a new AD: EASA AD 2010-0185-E.
>
> It grounds all Blaniks with immediate effect, including L-13, L-13A and
> all aircraft that passed earlier AD inspections. Reason is that the failed
> wing spar on the Austrian accident glider failed before reaching its
> theoretical lifetime, and it failed due to fatigue.
>
> Grounding is pending development of terminating action, which I imagine
> will take considerable time, and expense...
>
> Sorry to be the bearer of bad news...
>
> Eric Munk
> The Netherlands

"Terminating action" ???

Is that as bad as it sounds -- have all the L13's been reduced to
permanent
lawn ornament status? At least scrap aluminum alloy is going for
around
$1/lb these days... :(

-- Matt

[Stephen Thomas]

On Sep 6, 4:40*pm, BTiz > wrote:
> On Sep 6, 1:49*am, Eric Munk > wrote:
>
>
>
>
>
> > To whom it may concern,
>
> > EASA has just published a new AD: EASA AD 2010-0185-E.
>
> > It grounds all Blaniks with immediate effect, including L-13, L-13A and
> > all aircraft that passed earlier AD inspections. Reason is that the failed
> > wing spar on the Austrian accident glider failed before reaching its
> > theoretical lifetime, and it failed due to fatigue.
>
> > Grounding is pending development of terminating action, which I imagine
> > will take considerable time, and expense...
>
> > Sorry to be the bearer of bad news...
>
> > Eric Munk
> > The Netherlands
>
> It will be interesting how the US FAA handles this one.
> Anyone have a link to the EASA AD?

The BGA have published this link:


There is an update on the BGA website;

LET L13 Blanik - Grounding Notice and September Updates

EASA have just issued AD 2010-0185-E effective 5th September 2010
issuing a Prohibition of all Flights notice. You can view the AD here
- http://ad.easa.europa.eu/blob/easa_ad_2010_0185_E.pdf/EAD_2010-0185-E_1.

[Peter Scholz[_2_]]

Am 06.09.2010 17:40, BTiz wrote:
> On Sep 6, 1:49 am, Eric Munk > wrote:
>> To whom it may concern,
>>
>> EASA has just published a new AD: EASA AD 2010-0185-E.
>>
>> It grounds all Blaniks with immediate effect, including L-13, L-13A and
>> all aircraft that passed earlier AD inspections. Reason is that the failed
>> wing spar on the Austrian accident glider failed before reaching its
>> theoretical lifetime, and it failed due to fatigue.
>>
>> Grounding is pending development of terminating action, which I imagine
>> will take considerable time, and expense...
>>
>> Sorry to be the bearer of bad news...
>>
>> Eric Munk
>> The Netherlands
>
> It will be interesting how the US FAA handles this one.
> Anyone have a link to the EASA AD?

http://ad.easa.europa.eu/ad/2010-0185-E

[vaughn[_3_]]

"mattm" > wrote in message
...
> have all the L13's been reduced to permanent lawn ornament status?
>At least scrap aluminum alloy is going for around $1/lb these days... :

Well, there's an interesting current thread about sailplane wind vanes.

(Sorry for the gallows humor. This really is a serious subject.)

Vaughn

[Darryl Ramm]

On Sep 6, 10:14*am, nimbus > wrote:
> Our blanik has flown only 1200 hours. Has no cracks. Has all its EASA
> certification and historical papers.
>
> And now it is grounded. I am really upset about the way LET is
> conducting its business and communication about this issue.
>
> I can't even resale it because there is nobody who want to buy it in
> those days.
>
> Just can sell it for about 300 kg of aluminium as scrap or give it to
> a Air museum.
>
> Grrrrrrrrrrrrrrrrr

How do you *know* it has no fatigue cracks?

That's the root issue here.

Darryl

[nimbus]

We inspected every millimeter with Dye Check test inspection.
No cracks means no cracks..

[Morgans[_2_]]

"Scott" > wrote in message
.. .
> On 9-6-2010 20:50, nimbus wrote:
>> We inspected every millimeter with Dye Check test inspection.
>> No cracks means no cracks..
>>
>
> Well, the good news with that is that when they decide on a test
> procedure, you shouldn't have anything to worry about unless they mandate
> something like removing wing skins to inspect...

My guess is that with a problem of this magnitude, removing the wing skins
to replace the structure or to modify the structure is exactly what is going
to be required.

If I was an enterprising manufacturer, I would be designing a new wing kit
to sell to people with these grounded gliders. I would design it to use as
many parts from the old wing as possible.

It sounds to me as if the engineers of this glider really screwed the pooch,
with this mess. No way a well designed wing should be having this serious
of a problem, IMHO.
--
Jim in NC

[Frank Whiteley]

On Sep 6, 7:09*pm, "Morgans" > wrote:
> "Scott" > wrote in message
>
> .. .
>
> > On 9-6-2010 20:50, nimbus wrote:
> >> We inspected every millimeter with Dye Check test inspection.
> >> No cracks means no cracks..
>
> > Well, the good news with that is that when they decide on a test
> > procedure, you shouldn't have anything to worry about unless they mandate
> > something like removing wing skins to inspect...
>
> My guess is that with a problem of this magnitude, removing the wing skins
> to replace the structure or to modify the structure is exactly what is going
> to be required.
>
> If I was an enterprising manufacturer, I would be designing a new wing kit
> to sell to people with these grounded gliders. *I would design it to use as
> many parts from the old wing as possible.
>
> It sounds to me as if the engineers of this glider really screwed the pooch,
> with this mess. *No way a well designed wing should be having this serious
> of a problem, IMHO.
> --
> Jim in NC

IIRC, this is what they attempted to do over twenty years ago as
L-13's approached their initial life limits in the early-mids 1980's.
Return to factory for spar cap replacements. Some suspected it was a
make work attempt. Pressure was such that a 500 hour inspection
scheme was initiated in some countries. The troubling thing is that a
wing came off a 2300 hour glider in Austria. That said, the right
wing broke off an L-13 over Aspen, Colorado in August 1975 also with
two fatalities. The sketchy NTSB report cites severe turbulence at
cloud base and no fitted g-meter.

This latest EASA AD is still only suggesting that fatigue MAY be the
cause. Exceeding the flight envelope frequently is certainly another
possibility leading to wing failure or accelerated fatigue.

Frank Whiteley

[Morgans[_2_]]

"nimbus" > wrote
>
> Yes ! at what cost??? most probably twice the price of the remaining
> value of the Blanik glider.

I don't know the glider and the problem well enough to comment on the fix.
It may be as easy as developing a testing program, it may be reverse
engineering the fix talked about in this thread that has been performed on
other models.

All I am saying is that the terminating in the order is talking about
whatever fix has to take place to satisfy the company that the fix will make
the wing safe to fly and end the grounding order. That fix will be the
action taken on each plane that satisfies the company that each plane has
been made safe again and the order ended.

It may be that the inspection or fix is too expensive to justify. You can
bet that the company does not want any more deaths on it's head, and that
each plane will be certified safe, fixed or junked.

The terminating action is whatever repair or inspection to be made that
satisfies the company and the governing body of each country's aviation
authority that the grounding order may be safely lifted. The devil is in
the details of how the problem is resolved.
--
Jim in NC

[stephanevdv]

[quote] "It sounds to me as if the engineers of this glider really
screwed the pooch,
with this mess. No way a well designed wing should be having this
serious
of a problem, IMHO. " [unquote]

Given the fact that the Blanik has been in production since 1956 and
that numerous Blaniks have exceeded their normal service life of 10
000 hours without problems, I'd rather suspect something fishy about:

1) the use of this particular Blanik (only 2 300 hours total time, it
seems, but perhaps lots of 2-seat aerobatics);

or

2) a problem with the metallurgy of some parts, not conform to the
original as designed. Production methods have changed in half a
century, and there could even be differences between nominally
identical materials.

[midnav]

Im guessing an eddy-current inspection with rivets replaced with Hi-
locks or other removable fastener will be put into place. I think the
inspection and repair will be expensive, and the end result will be
that our L-13s will have a higher value. I spent a few moments looking
for two seat trainer replacements, there are very few out there.
Anyone check out the Blanik America web site? Not a word said about
the grounding of the fleet. Why would anyone in there right mind
purchase a LET product after they refuse to support existing models?

[nimbus]

I have a special question...

Why this AD applies only on Blanik L-13 and L-13A and NOT on L-23's???

Both glider type are very very similar....

[Bart[_4_]]

On Sep 7, 9:49*am, nimbus > wrote:
> I have a special question...
> Why this AD applies only on Blanik L-13 and L-13A and NOT on L-23's???
> Both glider type are very very similar....

According to Wikipedia, the first flight of L-23 took place in 1998.
This makes an average L-23 much younger than an average L-13.
Also, aren't L-23s still manufactured and sold?

B.

[Mike Schumann]

On 9/7/2010 11:49 AM, nimbus wrote:
> I have a special question...
>
> Why this AD applies only on Blanik L-13 and L-13A and NOT on L-23's???
>
> Both glider type are very very similar....

L-13 has a conventional tail, and flaps. L-23 has T tail, no flaps.
Canopies are different. Similarities: Both made of aluminum and the
manufacturer.

--
Mike Schumann

[Gilbert Smith[_2_]]

Mike Schumann > wrote:

>On 9/7/2010 11:49 AM, nimbus wrote:
>> I have a special question...
>>
>> Why this AD applies only on Blanik L-13 and L-13A and NOT on L-23's???
>>
>> Both glider type are very very similar....
>
>L-13 has a conventional tail, and flaps. L-23 has T tail, no flaps.
>Canopies are different. Similarities: Both made of aluminum and the
>manufacturer.

Does anyone still operate a Blanik in UK ??
I haven't seen one for years.
Maybe you should put struts on them, making them like all the other US
trainers ?