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Burt Compton - Marfa
April 6th 10, 09:52 PM
Information alert -- USA.
FAA Airworthiness Directive 2010-08-01 for Blanik L-23 sailplanes.

Cracks have been reported in 7 Blanik L-23 elevator / stabilizer
"inner" hinges by EASA (Europe.)

Inspection per the Blanik Mandatory Inspection Bulletin # L-23/052a
(dated March 2, 2010) for cracks must be accomplished by disassembly
and reassembly of the elevator from the stabilizer by an Airframe
mechanic and a logbook entry is required for compliance.

Appears that non-destructive / liquid or dye-penetrant inspection for
cracks must be accomplished per Mandatory Bulletin paragraphs A1, A2,
A4.

If not acomplished, your L-23 is grounded after April 26, 2010. .

For EASA (Europe) this will be a recurring AD, every 1,000 hours. FAA
has not set hours yet for repetitive inspections. Expect an amended
AD from FAA on repetitive inspections in the near future, as FAA may
determine the hours of Time In Service if more cracks are found during
this mandatory inspection of elevator hinges. There is a short
public comment period ending May 21, 2010.

Read and print this AD here: http://edocket.access.gpo.gov/2010/2010-7591.htm

Read and print the Blanik Mandatory Inspection Bulletin # L-23/052a
referenced in the FAA AD here: http://www.let.cz/files//bulletines/MB%20L23-052a_L23_English.pdf

Read the AD yourself, comply by April 26, 2010 and do not rely on this
message for guidance. This message is just an information alert to
fellow US Blanik L-23 owners.

Burt
Marfa, Texas USA

jcarlyle
April 6th 10, 10:26 PM
I can't understand why they'd specify liquid penetrant NDI. It can't
reliably find small cracks, and is easy to mis-use (with subsequent
false security that the part is not cracked). I'd go for eddy current
or ultrasound, myself. If you do use penetrant, make sure you follow
the directions precisely.

-John

On Apr 6, 4:52 pm, Burt Compton - Marfa > wrote:
> Information alert -- USA.
> FAA Airworthiness Directive 2010-08-01 for Blanik L-23 sailplanes.
>
> Cracks have been reported in 7 Blanik L-23 elevator / stabilizer
> "inner" hinges by EASA (Europe.)
>
> Inspection per the Blanik Mandatory Inspection Bulletin # L-23/052a
> (dated March 2, 2010) for cracks must be accomplished by disassembly
> and reassembly of the elevator from the stabilizer by an Airframe
> mechanic and a logbook entry is required for compliance.
>
> Appears that non-destructive / liquid or dye-penetrant inspection for
> cracks must be accomplished per Mandatory Bulletin paragraphs A1, A2,
> A4.
>
> If not acomplished, your L-23 is grounded after April 26, 2010. .
>
> For EASA (Europe) this will be a recurring AD, every 1,000 hours. FAA
> has not set hours yet for repetitive inspections. Expect an amended
> AD from FAA on repetitive inspections in the near future, as FAA may
> determine the hours of Time In Service if more cracks are found during
> this mandatory inspection of elevator hinges. There is a short
> public comment period ending May 21, 2010.
>
> Read and print this AD here: http://edocket.access.gpo.gov/2010/2010-7591.htm
>
> Read and print the Blanik Mandatory Inspection Bulletin # L-23/052a
> referenced in the FAA AD here: http://www.let.cz/files//bulletines/MB%20L23-052a_L23_English.pdf
>
> Read the AD yourself, comply by April 26, 2010 and do not rely on this
> message for guidance. This message is just an information alert to
> fellow US Blanik L-23 owners.
>
> Burt
> Marfa, Texas USA

Burt Compton - Marfa
April 6th 10, 11:59 PM
On Apr 6, 4:26*pm, jcarlyle > wrote:
> I can't understand why they'd specify liquid penetrant NDI. It can't
> reliably find small cracks, and is easy to mis-use (with subsequent
> false security that the part is not cracked). I'd go for eddy current
> or ultrasound, myself. If you do use penetrant, make sure you follow
> the directions precisely.
>
> -John
>

The comment period is to May 21, 2020.
With your expertise you could submit an alternate means of compliance
suggestion to the FAA.
Let us know how it works out.

Burt
Marfa, Texas USA

Burt Compton - Marfa
April 7th 10, 12:01 AM
Corrected date to May 21, 2010.

> The comment period is to May 21, 2020.
> With your expertise you could submit an alternate means of compliance
> suggestion to the FAA.
> Let us know how it works out.
>
> Burt
> Marfa, Texas *USA

Tony[_5_]
April 7th 10, 12:02 AM
On Apr 6, 6:01*pm, Burt Compton - Marfa > wrote:
> Corrected date to May 21, 2010.
>
> > The comment period is to May 21, 2020.
> > With your expertise you could submit an alternate means of compliance
> > suggestion to the FAA.
> > Let us know how it works out.
>
> > Burt
> > Marfa, Texas *USA

the AD must be complied with before the comment period is closed?
that's weird...

BT[_3_]
April 7th 10, 02:13 AM
"Tony" > wrote in message
...
> On Apr 6, 6:01 pm, Burt Compton - Marfa > wrote:
>> Corrected date to May 21, 2010.
>>
>> > The comment period is to May 21, 2020.
>> > With your expertise you could submit an alternate means of compliance
>> > suggestion to the FAA.
>> > Let us know how it works out.
>>
>> > Burt
>> > Marfa, Texas USA
>
> the AD must be complied with before the comment period is closed?
> that's weird...

Not so weird... it's an emergency safety of flight issue.
The comment period can be used to discuss the recurrent inspection
requirements which are not part of the emergency AD issue.

[quote from the AD ]This AD is considered an interim action because we are
not
including the action that you repetitively inspect the elevator inner
hinges on the stabilizer at intervals not to exceed every 1,000 hours
time-in-service (TIS). The Administrative Procedure Act does not permit
the FAA to ``bootstrap'' a long-term requirement into an urgent safety
of flight action where the rule becomes effective at the same time the
public has the opportunity to comment. The short-term action and the
long-term action are analyzed separately for justification to bypass
prior public notice.
After issuing this AD, we may initiate further AD action (notice of
proposed rulemaking followed by a final rule) to require that you
repetitively inspect the elevator inner hinges on the stabilizer at
intervals not to exceed every 1,000 hours TIS. Credit will be given in
any subsequent action for the initial inspection done under this AD.
[/end quote]

BT

jcarlyle
April 7th 10, 02:10 PM
Unfortunately, I don't have access to a L-23, so my suggestions
wouldn't be on target. If anyone who has to do the inspection would
like NDI advice, please do get in contact with me off line.

-John

On Apr 6, 6:59 pm, Burt Compton - Marfa > wrote:
> The comment period is to May 21, 2020.
> With your expertise you could submit an alternate means of compliance
> suggestion to the FAA.
> Let us know how it works out.

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