Piper 235 tail skin

[Ross]

Jay and other owners of this aircraft. Any documentation on cracks
forming on the horizontal tail surfaces. The -235 I am helping on annual
had three additional cracks in the skin beyound the two that were
repaired by the previous owner. Got some old skin and made conforming
patches.
--

Regards, Ross
C-172F 180HP
KSWI

[Jay Honeck[_2_]]

> Jay and other owners of this aircraft. Any documentation on cracks
> forming on the horizontal tail surfaces. The -235 I am helping on annual
> had three additional cracks in the skin beyound the two that were
> repaired by the previous owner. Got some old skin and made conforming
> patches.

Never heard of that before...but I'll ask around.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[WingFlaps]

On Feb 26, 11:41*am, Ross > wrote:
> Jay and other owners of this aircraft. Any documentation on cracks
> forming on the horizontal tail surfaces. The -235 I am helping on annual
> had three additional cracks in the skin beyound the two that were
> repaired by the previous owner. Got some old skin and made conforming
> patches.
> --

Is this due to some sort of oil canning? If so, is the spar OK?

Cheers

[Denny]

> Is this due to some sort of oil canning? If so, is the spar OK?

Right on...

The skin is vibrating...

Better have someone who is sharp, check the engine mounts and prop
balance...
Go for a short flight with a second person to video the horizontal
stab in flight...

denny

[Dave[_19_]]

Where are the cracks located Ross?

I do not think ANY cracks are permitted on the control surface areas,
depending on the year of manufacture.

I am absolutey positive about this on rhe rudder and ailerons...they
need new skins.

Stabilator? not sure..

You might ask on the Cherokee chat group..someone there WILL know..
ALL known about Cherokees is in that group!

Dave




On Mon, 25 Feb 2008 16:41:07 -0600, Ross > wrote:

>Jay and other owners of this aircraft. Any documentation on cracks
>forming on the horizontal tail surfaces. The -235 I am helping on annual
>had three additional cracks in the skin beyound the two that were
>repaired by the previous owner. Got some old skin and made conforming
>patches.

[Ross]

Dave wrote:
> Where are the cracks located Ross?
>
> I do not think ANY cracks are permitted on the control surface areas,
> depending on the year of manufacture.
>
> I am absolutey positive about this on rhe rudder and ailerons...they
> need new skins.
>
> Stabilator? not sure..
>
> You might ask on the Cherokee chat group..someone there WILL know..
> ALL known about Cherokees is in that group!
>
> Dave
>
>
>
>
> On Mon, 25 Feb 2008 16:41:07 -0600, Ross > wrote:
>
>
>>Jay and other owners of this aircraft. Any documentation on cracks
>>forming on the horizontal tail surfaces. The -235 I am helping on annual
>>had three additional cracks in the skin beyound the two that were
>>repaired by the previous owner. Got some old skin and made conforming
>>patches.
>
>

They are on the horizontal stabilator. All go across the raised portion
that Piper blends into the skin (skin stiffiners ?). The patches were
made out of the same skin material so it would fit nicely. All are on
the starbord (right) side of the aircraft and more inboard. 4 were on
the top. Two previously patched years ago. And a new one on the bottom
(at least it was not stopped drilled like the two on the top not
patched. Engine mounts look to be fine.

--

Regards, Ross
C-172F 180HP
KSWI

[[email protected]]

Skin crack patches are not permitted on the stabilator or rudder or
vertical stab of any PA28 models. You must re-skin to be legal.
Fortunately PA28 tailfeather skins are readily available from Piper or
authorized parts dealers and are not too awful expensive either. The
labor to drill out all the old rivets and replace is the real PITA
here.

BTW, patches *are* permitted on PA28 flap skins, and believe it or
not, also on aileron skins for older cherokees, but you must rebalance
ailerons if you patch them. The PA28 service manual even has a section
that tells you what thickness aluminum to use for those skin patches.

[Ross]

wrote:
> Skin crack patches are not permitted on the stabilator or rudder or
> vertical stab of any PA28 models. You must re-skin to be legal.
> Fortunately PA28 tailfeather skins are readily available from Piper or
> authorized parts dealers and are not too awful expensive either. The
> labor to drill out all the old rivets and replace is the real PITA
> here.
>
> BTW, patches *are* permitted on PA28 flap skins, and believe it or
> not, also on aileron skins for older cherokees, but you must rebalance
> ailerons if you patch them. The PA28 service manual even has a section
> that tells you what thickness aluminum to use for those skin patches.
>

As so often said here, pardon me, what is the reference for "not
permitted"? Is is a Piper document or what? I would like to make it
available to the owner.

--

Regards, Ross
C-172F 180HP
KSWI

[[email protected]]

On Feb 26, 1:51 pm, Ross > wrote:
>
> As so often said here, pardon me, what is the reference for "not
> permitted"? Is is a Piper document or what? I would like to make it
> available to the owner.

I believe this is written in the Piper PA28 Service manual itself. I
have the Essco Aircraft reprints of these manuals at home and can
probably look up the exact section, page and paragraph later this
evening. I distinctly remember reading this info in the manual, as I
was looking to buy a Cherokee that has a skin patch on one of the flap
skins and wanted to be sure it was an approved repair.

[Dave[_1_]]

RUH ..ROH...

Ross, something is very wrong here...

Here is the entry, sec 4-55 of my (PA28-151) manual...


IN BOLD ITALICS....

WARNING!

The use of patch plates for repairs of all moveable tail surfaces is
prohibited The use if any filler material normally used for the repair
of minor dents and/or materials used for filling the inside of
surfaces is also prohibited on all moveable tail surfaces.

I understand "stop drilling " is also prohibited...

We found cracks (two, 1in long) in our rudder stop drilled when we
purchased.. reskinned.

Small crack in port aileron found when paint removed... reskinned.

FIVE cracks... something is happening INSIDE the stabilator...

Cherokees are tough birds...this should NOT be happening...

I would not fly this aircraft..

Dave



On Tue, 26 Feb 2008 11:12:43 -0600, Ross > wrote:

>Dave wrote:
>> Where are the cracks located Ross?
>>
>> I do not think ANY cracks are permitted on the control surface areas,
>> depending on the year of manufacture.
>>
>> I am absolutey positive about this on rhe rudder and ailerons...they
>> need new skins.
>>
>> Stabilator? not sure..
>>
>> You might ask on the Cherokee chat group..someone there WILL know..
>> ALL known about Cherokees is in that group!
>>
>> Dave
>>
>>
>>
>>
>> On Mon, 25 Feb 2008 16:41:07 -0600, Ross > wrote:
>>
>>
>>>Jay and other owners of this aircraft. Any documentation on cracks
>>>forming on the horizontal tail surfaces. The -235 I am helping on annual
>>>had three additional cracks in the skin beyound the two that were
>>>repaired by the previous owner. Got some old skin and made conforming
>>>patches.
>>
>>
>
>They are on the horizontal stabilator. All go across the raised portion
>that Piper blends into the skin (skin stiffiners ?). The patches were
>made out of the same skin material so it would fit nicely. All are on
>the starbord (right) side of the aircraft and more inboard. 4 were on
>the top. Two previously patched years ago. And a new one on the bottom
>(at least it was not stopped drilled like the two on the top not
>patched. Engine mounts look to be fine.

[Ross[_2_]]

wrote:
> On Feb 26, 1:51 pm, Ross > wrote:
>
>>As so often said here, pardon me, what is the reference for "not
>>permitted"? Is is a Piper document or what? I would like to make it
>>available to the owner.
>
>
> I believe this is written in the Piper PA28 Service manual itself. I
> have the Essco Aircraft reprints of these manuals at home and can
> probably look up the exact section, page and paragraph later this
> evening. I distinctly remember reading this info in the manual, as I
> was looking to buy a Cherokee that has a skin patch on one of the flap
> skins and wanted to be sure it was an approved repair.

Thanks, that is what I am looking for.

Ross

[WJRFlyBoy]

On Mon, 25 Feb 2008 16:41:07 -0600, Ross wrote:

> Jay and other owners of this aircraft. Any documentation on cracks
> forming on the horizontal tail surfaces. The -235 I am helping on annual
> had three additional cracks in the skin beyound the two that were
> repaired by the previous owner. Got some old skin and made conforming
> patches.

No Piper service releases on this problem?
--
Remove numbers for gmail and for God's sake it ain't "gee" either!

[[email protected]]

On Feb 26, 6:02 pm, Dave > wrote:
> RUH ..ROH...
>
> Ross, something is very wrong here...
>
> Here is the entry, sec 4-55 of my (PA28-151) manual...
>
> IN BOLD ITALICS....
>
> WARNING!
>
> The use of patch plates for repairs of all moveable tail surfaces is
> prohibited The use if any filler material normally used for the repair
> of minor dents and/or materials used for filling the inside of
> surfaces is also prohibited on all moveable tail surfaces.
>
> I understand "stop drilling " is also prohibited...
>

That is the same exact thing that's in my service manual, which is
also the Cherokee Warrior PA-28-151 & -161 edition (part # 761 539),
and doesn't seem to cover the -235 models specifically.

I did find these interesting threads over on the piperowners.org
forum, which seems to suggest that the older straight-wing Cherokee
service manual did not have the prohibition against patching control
surfaces.
http://forums.piperowner.org/read/1/36932/37096#msg-37096

http://forums.piperowner.org/read/1/84556/84710#msg-84710

[JGalban via AviationKB.com]

wrote:
>
>I did find these interesting threads over on the piperowners.org
>forum, which seems to suggest that the older straight-wing Cherokee
>service manual did not have the prohibition against patching control
>surfaces.

It might be the difference between an old manual and a current one. I have
an ancient copy of the PA28 service manual and it doesn't prohibit control
surface skin repairs. When a crack jumped the stop-drill hole on my rudder,
my IA declined to repair it (had to reskin). We compared service manuals and
my old one didn't have the prohibition, but his current one did. Word on a
Piper forum was that the prohibition was added to the PA28 manuals by Piper
in the 90s (which would explain why my old skin was stop drilled).

John Galban=====>N4BQ (PA28-180)

--
Message posted via http://www.aviationkb.com

[Ray Andraka]

JGalban via AviationKB.com wrote:

> wrote:
>
>>I did find these interesting threads over on the piperowners.org
>>forum, which seems to suggest that the older straight-wing Cherokee
>>service manual did not have the prohibition against patching control
>>surfaces.
>
>
> It might be the difference between an old manual and a current one. I have
> an ancient copy of the PA28 service manual and it doesn't prohibit control
> surface skin repairs. When a crack jumped the stop-drill hole on my rudder,
> my IA declined to repair it (had to reskin). We compared service manuals and
> my old one didn't have the prohibition, but his current one did. Word on a
> Piper forum was that the prohibition was added to the PA28 manuals by Piper
> in the 90s (which would explain why my old skin was stop drilled).
>
> John Galban=====>N4BQ (PA28-180)
>

That is my understanding as well. Additionally, you must use the latest
service manual, so repairs done now have to conform to the current
service manual, as I understand it. I don't believe you need to go back
and change old repairs if they were correct for the service manual
revision that was current when the repair was done.

[[email protected]]

wrote:
: Skin crack patches are not permitted on the stabilator or rudder or
: vertical stab of any PA28 models. You must re-skin to be legal.
: Fortunately PA28 tailfeather skins are readily available from Piper or
: authorized parts dealers and are not too awful expensive either. The
: labor to drill out all the old rivets and replace is the real PITA
: here.

: BTW, patches *are* permitted on PA28 flap skins, and believe it or
: not, also on aileron skins for older cherokees, but you must rebalance
: ailerons if you patch them. The PA28 service manual even has a section
: that tells you what thickness aluminum to use for those skin patches.

This is a point of confusion, IMO. As far as I can tell from my PA28 service manual, control
surface repairs are possible, since they have a description of how to do it. That includes how to check
the balance and state that they're often balanced at the forward end of the range to "allow for repairs."
The only "official" information I've heard that says repairs aren't permitted has been 3rd or 4th
generation word of mouth. I've also seen a number of PA28's *with* control surface repairs.

What gives?

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[[email protected]]

: It might be the difference between an old manual and a current one. I have
: an ancient copy of the PA28 service manual and it doesn't prohibit control
: surface skin repairs. When a crack jumped the stop-drill hole on my rudder,
: my IA declined to repair it (had to reskin). We compared service manuals and
: my old one didn't have the prohibition, but his current one did. Word on a
: Piper forum was that the prohibition was added to the PA28 manuals by Piper
: in the 90s (which would explain why my old skin was stop drilled).

: John Galban=====>N4BQ (PA28-180)

I can find no such prohibition in my service manual (P/N 753-586, Feb 27, 2004). It contains
information (skin thickness, checking balance, etc) on how to do it.

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Morgans[_2_]]

> wrote

> This is a point of confusion, IMO. As far as I can tell from my PA28
> service manual, control
> surface repairs are possible, since they have a description of how to do
> it. That includes how to check
> the balance and state that they're often balanced at the forward end of
> the range to "allow for repairs."
> The only "official" information I've heard that says repairs aren't
> permitted has been 3rd or 4th
> generation word of mouth. I've also seen a number of PA28's *with*
> control surface repairs.
>
New thinking at Piper, as reflected in newer manuals, says to replace and
not patch the skins. I would think they have discovered important reasons
to make that change.

The biggest thing that would eat at me, is why the skin cracked, and what is
going on inside there that you can not see without taking the skin off.
Something caused it to crack, and I would not fly comfortable, without
knowing what that was.

If you find peace of mind with patches, more power to you. Keep on keeping
on, then. :-)
--
Jim in NC

[JGalban via AviationKB.com]

wrote:
>
> I can find no such prohibition in my service manual (P/N 753-586, Feb 27, 2004). It contains
>information (skin thickness, checking balance, etc) on how to do it.
>

That's strange. When my IA showed me his current manual (on CD), it had
the prohibition. As I recall, it was worded the same as described in Dave's
post above.

John Galban=====>N4BQ (PA28-180)

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums.aspx/aviation/200803/1

[Jay Honeck[_2_]]

> New thinking at Piper, as reflected in newer manuals, says to replace and
> not patch the skins. I would think they have discovered important reasons
> to make that change.

Yeah, they discovered that they could charge $1600 for a $12 piece of
pressed aluminum.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Mike Spera]

Jay Honeck wrote:
>> New thinking at Piper, as reflected in newer manuals, says to replace
>> and not patch the skins. I would think they have discovered important
>> reasons to make that change.
>
>
> Yeah, they discovered that they could charge $1600 for a $12 piece of
> pressed aluminum.

AND likely avoid liability by ensuring a repaired crack does not show up
at a crash site.

[Morgans[_2_]]

"Mike Spera" > wrote

> AND likely avoid liability by ensuring a repaired crack does not show up
> at a crash site.

Sounds good, if it means I am not arriving at the crash site a few
milliseconds before the cracked spar.

Really, guys and gals; do you want to go flying around with a spar that is
stop drilled?

Not me.
--
Jim in NC

[Scott Skylane]

Morgans wrote:

> "Mike Spera" > wrote
>
>
>>AND likely avoid liability by ensuring a repaired crack does not show up
>>at a crash site.
>
>
> Sounds good, if it means I am not arriving at the crash site a few
> milliseconds before the cracked spar.
>
> Really, guys and gals; do you want to go flying around with a spar that is
> stop drilled?
>
> Not me.

Well, we're talking about cracked *skins* here, not spars. See the
thread title. I believe Piper's ability to charge $1600 for a $12 part,
coupled with potential liability, is exactly what drove this policy change.

Happy Flying!
Scott Skylane

[Peter Clark]

On Wed, 05 Mar 2008 20:39:40 -0900, Scott Skylane
> wrote:

>Morgans wrote:
>
>> "Mike Spera" > wrote
>>
>>
>>>AND likely avoid liability by ensuring a repaired crack does not show up
>>>at a crash site.
>>
>>
>> Sounds good, if it means I am not arriving at the crash site a few
>> milliseconds before the cracked spar.
>>
>> Really, guys and gals; do you want to go flying around with a spar that is
>> stop drilled?
>>
>> Not me.
>
>Well, we're talking about cracked *skins* here, not spars. See the
>thread title. I believe Piper's ability to charge $1600 for a $12 part,
>coupled with potential liability, is exactly what drove this policy change.

If you can find a DER who disagrees with Piper's engineering that
calls for replacement instead of repair could you repair it and do a
337 under the DERs signoff?

[[email protected]]

: That's strange. When my IA showed me his current manual (on CD), it had
: the prohibition. As I recall, it was worded the same as described in Dave's
: post above.

: John Galban=====>N4BQ (PA28-180)

: --
: Message posted via AviationKB.com
: http://www.aviationkb.com/Uwe/Forums.aspx/aviation/200803/1

Might want to check that P/N on the manual. Yours is a hershey-bar -180, right? I was starting
to think that only the taper-wings had the prohibition in there.

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[[email protected]]

: >Well, we're talking about cracked *skins* here, not spars. See the
: >thread title. I believe Piper's ability to charge $1600 for a $12 part,
: >coupled with potential liability, is exactly what drove this policy change.

: If you can find a DER who disagrees with Piper's engineering that
: calls for replacement instead of repair could you repair it and do a
: 337 under the DERs signoff?

Piper *themselves* disagree with Piper. I challenge you to find NTSB reports of *properly*
executed skin patches being a factor in a crash. So long as the dynamic balance of the control surface
is within range, the repair is done according to AC43 (or in Piper's case, THEIR OWN SERVICE MANUAL!),
it's perfectly safe. I agree that the only reasons for the changes are
- Limiting liability wherever possible.
- Charging insane prices for replacement skins.

Think about it... why in the hell would they encourage a $100 repair on a plane they sold 40
years ago if they could play the legally-cautious and $1600 financially-beneficial route of mandating
skin replacements?

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[JGalban via AviationKB.com]

wrote:
>
> Might want to check that P/N on the manual. Yours is a hershey-bar -180, right? I was starting
>to think that only the taper-wings had the prohibition in there.
>

Good point. My old manual covered all of the PA28 variants. I wasn't
aware that they now had separate manuals for the tapered wing models.

Thanks,

John Galban=====>N4BQ (PA28-180)

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums.aspx/aviation/200803/1