Upcoming AD for many more PA-28 and PA-36 wing spars. 100 anomalies and 6 cracked wings found

This is a big damn deal.
Is it as big as many seem to make it here? I don’t think most of the privately owned airplanes will qualify, no?

Lots of back and forth to sift through, but let me try to break it down - please correct me if I’m wrong - If you have complete maintenance records and are under 12,000 hours, then this does not apply?
 
I'm trying to understand where my PA-28R-200 is in this. It had "Piper Serivce Kit 764-998" applied that was referred to as "spar doubler" in the log book. Work was done in 2021 before I was the owner. Is this the reinforcement kit that is referred to?

EDIT: Disregard, I figured out what this is.
 
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yeah... My plane rolled off the factory floor 2 months before Watergate happened in '72; no ****ing way I'm expecting a check from Piper to compensate me for spar work 52 years later.
The whole revive-GA thing in the 90s was an 18 year limit on liability for this reason. Unlimited liability and service doesn't make sense, especially when the manufacturer can't force you to follow any kind of inspection or maintenance program.

The issue is that realistically, it doesn't matter what the spar costs. The labor to put it in will make it a rounding error. The entire wing is built around it & attached to it. You're basically building a new wing from scratch. It might be economical for some newer planes, and maybe some Six-300's, but the older ones will just get scrapped.
A fair point. In fact I wonder if replacing the wing would end up being the same price or cheaper given the amount of riveting required to replace a spar?
Back to the planes. I'll have to read the NPRM again, but it seems that Archers manufactured in the 21st century will be impacted as well. Those owners will also get the shaft and nothing else.
Yes. I suspect Piper's investigation started around the time of the prior AD. They may have even hired some outside engineering to investigate the metallurgy. So the change to machining the spar instead of cold forming would have been in the past few years.

Realistically, I know we can't expect Piper to do this for free. They'd go bankrupt in a day. But here's a draft approach worth considering:
They should build a few more sets of wing jigs and spread them across the country, allowing owners (private or flight schools) and A&Ps access to them (use a scheduling program) to replace the spars. And they should consider providing spars at (or slightly above) cost and tech support to allow that to happen in a timely manner. Maybe have a number of wing shipping crates available as well, with discounted rates to ship wing sets to wherever those jigs would be located.
That way, a 30k+ spar replacement (which would probably mean the end of that airframe) might become an affordable option.
I don't think there is an established process for this beyond the existing Parts Manufacturing Authority. If the AD continues to grow it is possible a third party company could economically seek PMA but it won't be cheap to have an engineering firm reverse-engineer the spar design and metallurgical properties then get the FAA to sign off. Another option is Piper licensing the design to one or more third parties which certainly makes getting PMA approval easier.

Piper providing the engineering drawings and specs publicly would solve the "required data" problem for an owner-produced part. In theory if Piper wanted to do so they could release that information and an owner could retain a machine shop to manufacture a new spar to Piper's specifications. The FAA would certainly accept that - its in the FARs already. Not sure what (if any) liability Piper would have.


One number that I would like to see is the calculated fatigue life of the spar (original and replacement). That number is not infinite, that's a given.
For original spars it appears that it can vary significantly depending on how the spar is treated, if the wing was ever removed, etc. As mentioned the stress in the metal at that location makes it very sensitive to even minor nicks and gouging. An original spar treated gently and never having its bolts removed will probably last a very long time. But if your wing was assembled on a Friday by the new guy who horsed the bolt in your spar might have some scrapes from the bolt threads that greatly accelerate the cracking process. Or if it had a wing strike 3 owners back and the mechanic took the wing off without properly unloading it. If it was purely a lifetime thing it would be easier to just set a limit and be done with it.
 
but it should be looked into what solutions could be done. The kit for example is a start. Also I’m sure they (Piper) have insurance to cover mistakes. To put everything on the airplane owners themselves isn’t exactly fair either. We have a reasonable expectation to safe products.
If their estimations are correct, the kit is actually the worst option financially (to my dismay). Check out their projected math in terms of expected labor hours.
1727285178617.png

Not to mention I think you and me are both hosed @mandm since I think we're both in the *R-180 and *R-200, which don't have modification kits available...
1727285240819.png

It would be great to see a palatable option presented, though I get the feeling Piper isn't going to be working to deliver one
 
Is it as big as many seem to make it here? I don’t think most of the privately owned airplanes will qualify, no?

Lots of back and forth to sift through, but let me try to break it down - please correct me if I’m wrong -

If you have complete maintenance records and are under 12,000 hours, then this does not apply?
One of the documents says 3000 hours (minus each 100 hour inspection from 3000 though), but if you have zero 100 hour inspections then you can double or triple it depending if you have <200HP or >200HP.

It’s all proposed as well, so will take time to go through the comments and final rulemaking.

And I could be wrong, I think we are all digesting this with some added emotion in play.
 
If you have complete maintenance records
That can be a very slippery slope. Hangar mate found someone, three or four owners ago, installed an unapproved (and non-TSOd) carb temp gauge in the panel.
No logbook entry for it.
We could make the argument that his plane has incomplete maintenance records, as irrelevant as that gauge is to the whole spar issue.
 
Is it as big as many seem to make it here? I don’t think most of the privately owned airplanes will qualify, no?

Lots of back and forth to sift through, but let me try to break it down - please correct me if I’m wrong - If you have complete maintenance records and are under 12,000 hours, then this does not apply?
I think the interpretation is incorrect that everyone under 12k is exempt. At a minimum there seems to be a progressive schedule of required inspections that is being proposed, starting at 3000 CSH or 4500 CSH depending on your aircraft "group". The good news is that if you're flying non-commercial ops, your CSH only accrues at +1/3hr or +1/2hr, per hour you fly, based on which group you're in for grps 1 and 2, respectively.

Where the emotion comes in is there's probably a fair number of buyers who did all their homework, were diligent in getting thorough prebuys w/ECIs on Arrows/PA28s that were higher-time former flight school/commercially used planes, who will suddenly find themselves in a bad position. I can think of one guy in particular a few hangar buildings down from me who will be in a really bad spot if this passes. You got the ECI test and a clean bill of health and thought you were good, then this gets dropped on you. Even if your repetitive inspections show good results, you have a lingering huge bill hanging over you and the next buyer knows it.

There's also the people who bought planes with missing logs, negotiated appropriately for a lower price, and now would be instantly catapulted into the worst category. That is... painful.

I don't see a lot of scenarios where prices wouldn't come down a bit on PA28s/Arrows to compensate for this. Even before its passed or if it never passes. Just the lingering threat of it will hurt a lot of the fleet's value. I bet we'll see a slowdown in the number of high time arrows/pa28s changing hands over the next year or so.

EDIT: Also here's the current composition for TTAFs for the market. No guarantee its representative of the TTAF for whole fleet, though.
1727296725976.png

NOTE: Despite reading the registers like 4x now, I'm still no expert in parsing this language. So if I misspoke, please correct me :)
 
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My Arrow had one wing spar replaced as part of the prebuy, I was told it was around 20k and it took probably 4 months.

Has anyone asked Piper how long they expected their airplanes to last for?

Not saying Piper should go bankrupt over this, but it should be looked into what solutions could be done. The kit for example is a start. Also I’m sure they (Piper) have insurance to cover mistakes. To put everything on the airplane owners themselves isn’t exactly fair either. We have a reasonable expectation to safe products.

For how long after manufacture? How many years should Piper be held liable?
 
Is it as big as many seem to make it here? I don’t think most of the privately owned airplanes will qualify, no?
Depends. As mentioned there will be two ADs. If your aircraft falls under AD1 requiring the calculation of a CSH, you will have an on-going commitment up to the service life of the spar. AD1 will supersede AD 2020-26-16 which had the FSH calculation.

Since the AD1 NPRM will allow an owner with PPC to review the records, each applicable owner should calculate their specific CSH and see where you stand. I think for most average-history recreational aircraft the inspection schedule will probably be a non-issue once established. However, for high-time, training/aerial work history aircraft things could be on a short leash.

AD2 is a catch-all to address aircraft that use the same base spar arrangement as the AD1 effectivity, but do not have the history or the other indicators to warrant a CSH track. As with AD1, a PPC can determine the applicability and due times for the 12,000 hr requirement. With a complete mx record history its at 12,000 flight hours; for incomplete record history I believe its 100hrs/60 days to comply with inspection. If by chance you had an equivalent inspection performed prior to the AD2 effective date on aircraft with spar T.T. over 12,000hrs then you will get credit for the inspection.

So until each owner calculates their specific position for AD1 or AD2, whether it’s a “big deal” or not won’t be known. I would also recommend every Piper owner make comments on both AD NPRMs that any current or proposed spar life-limits would not be appropriate for Part 91 recreational aircraft and the use of a higher level, “off-wing” inspection method should be adopted instead. Strive to get 20,000 comments if at all possible.
 
What Arrows are over 200 HP?

200 is not above 200.
I didn't say arrows over 200hp. I said 28s over 200 hp. Which is really just the Pathfinder and Dakota.

But you're right, it does include all arrows too, so it was poorly worded.
 
What I really mean is that Piper could probably just as soon not make the part at all: let the FAA implement their rule, let good spars become unobtanium, and then the fleet dies off. Then we can all go buy new Pipers and support them in the 21st century.
As a biz model, I don't think when they built the planes back in the Vietnam War era they really intended to support them into perpetuity free-of-charge (i.e., not making a profit on new parts).
Sort of like the magnesium ruddervators?
 
what in the swang song, people be blowing up my DMs with hyperlin---ooooooooh...
well, gonna need a running start for this one...



















P.S. I owe Lycoming an apology. Even when I thought that grey thing tried to kill me.... turns out it was trying to save all along. And it did.

Please forgive me, dear Father-Lyco, for I uttered your name in vain, so many times in 2023.
For I once was lost, but now I Seeeeeeeeee.:happydance::rofl:
 
Not saying Piper should go bankrupt over this, but it should be looked into what solutions could be done. The kit for example is a start. Also I’m sure they (Piper) have insurance to cover mistakes. To put everything on the airplane owners themselves isn’t exactly fair either. We have a reasonable expectation to safe products.
How is it a "mistake" if the inspection requirement for most affected aircraft is 12,000 hours or some similarly large calculated value?

Considering that, the almost insignificant number of failures and faults found so far along with impossibility of determining how these aircraft have been flown over multiple decades, I find it remarkable anyone is pointing a finger at Piper.
 
Not saying Piper should go bankrupt over this, but it should be looked into what solutions could be done. The kit for example is a start. Also I’m sure they (Piper) have insurance to cover mistakes. To put everything on the airplane owners themselves isn’t exactly fair either. We have a reasonable expectation to safe products.
Piper already went bankrupt once, well after your Arrow was built. The company that emerged was called "New Piper". Very original. Product liability insurance was a factor for that bankruptcy.

I do agree that engineering a solution other than total spar replacement would be nice. But if you had a pre 79 pa32, could you even add all the doublers of that 79 spar and if that cost of labor would even be worth it.
 
This may be considered leveling the playing field.

Some FAR 23 aircraft are assigned a “Wing Life” at Certification.

Varies but I think some are at 12K.
 
Some FAR 23 aircraft are assigned a “Wing Life” at Certification.
If you read the work group paper/NPRM for the rewrite of Part 23 the reasoning behind the added structural limitations was due to the extended service life being seen with those small Part 91 aircraft. However, Part 23 allows for the use of either a structural life limit or tiered inspection system.

This was the same reason Cessna developed their SID program years ago. Piper didn’t seem to follow the same path and now are caught with a design/production process that has basically aged out. What I hope doesn’t happen is the FAA follows the Australian CASA and make SIDs and similar processes mandatory for all Part 91 aircraft.

But in reality, this is the last TC’d aircraft group that does not have some sort of age based inspection requirement. However, if there was a regulatory move in that direction, I would hope the FAA would differentiate between aircraft usage history like the twin Piper spar ADs and apply that logic to any mandatory age-based aircraft inspection programs.
 
Bell’s comments make sense to me.

Rockwell is only 6945 hrs and T-hawk is 11K .

Might have been extended by mods though.

Nothing is forever.

( insert joke here)

The house needs a roof. The car needs an engine or tranny.

Things are made better which causes more problems to be

evident long term. Cherokees are not alone.
 
"iT iS wUt iT iS." Official sponsor of the We Be Thriving!TM Series Motivational Speaker Tour. Coming Soon to a swamp@ssed OSH25 booth near you!
 
What year did Piper got to the machined spar in the Archer? I see a sort of reference that makes me think 2020.
 
I hear ya. I have a 1965 Ford Fairlane, the damn floorboards rusted through. And you would think Ford would be responsible for this, after all they made it! And Ford expects me to pay for the repairs myself! The nerve!

Here’s the deal. Those airbags were on vehicles produced in this century.

Complaining about something that was produced over a half century ago and expecting a manufacture to warranty a product indefinitely is ludicrous.

Truth. I don't think any of the manufacturers thought these spam cans would still be flying 50-60+ years after they were built.
 
There is certainly precedent for this on the Cessna side. When the AD on 210 carry-through spar came out, there was a small, but significant number of planes that had corrosion in critical areas and could not pass NDT inspection. Cessna, to their credit, stepped up and starting making new parts. They weren't cheap ($10K-$20K in parts and an equal amount in labor), but it was better than sending an otherwise healthy airplane to the bone yard.

C.
 
I know there are some high-hour airframes out there but how many? If I'm reading this right my spars aren't even halfway to their life limit yet.
 
Some FAR 23 aircraft are assigned a “Wing Life” at Certification.

Varies but I think some are at 12K.
Including, notably, the PA-44 Seminole which is essentially a twin Arrow IV and has a wing life limit at 14,663 hours (or 16,462 hours for the Turbo Seminole). I wonder what style of spar it has.
 
Piper commented, interesting read:

Wow.

Thanks for posting... that's a great read. Totally the opposite of the NPRM. Piper is really sticking their neck out to protect the fleet; I'm kind of amazed. The NPRM reads like it was written hand in hand with piper, but that was clearly not the case.

Perhaps the most enlightening part was where they cover all 11 aircraft with confirmed cracks. 2 pipeline (in the 80s, they counted those too), 3 ERAU, 2 freight dogs with oversize tires and history of multiple landing gear replacements, 1 on a 15,000 hour scrapyard replacement wing, and the rest with other known damage history or lost logs/ presumed damage history.

I was also glad to see them clarify the compliance costs, as well as call out FAA's nonsense $85/hr shop rate.

How do these things get adjudicated? I know the FAA has to respond to all comments, but they can still do pretty much what they want, right? Will Piper's strong response here carry enough weight to stop or at least change this AD?
 
Pretty aligned with what I have posted on this thread and others. The cure is potentially worse than the disease and the cure can cause the disease.
 
Wow.

Thanks for posting... that's a great read. Totally the opposite of the NPRM. Piper is really sticking their neck out to protect the fleet; I'm kind of amazed. The NPRM reads like it was written hand in hand with piper, but that was clearly not the case.

Perhaps the most enlightening part was where they cover all 11 aircraft with confirmed cracks. 2 pipeline (in the 80s, they counted those too), 3 ERAU, 2 freight dogs with oversize tires and history of multiple landing gear replacements, 1 on a 15,000 hour scrapyard replacement wing, and the rest with other known damage history or lost logs/ presumed damage history.

I was also glad to see them clarify the compliance costs, as well as call out FAA's nonsense $85/hr shop rate.

How do these things get adjudicated? I know the FAA has to respond to all comments, but they can still do pretty much what they want, right? Will Piper's strong response here carry enough weight to stop or at least change this AD?
Well just imagine you work for the FAA, not an engineer, halfway to your retirement and are responsible for signing off on an AD for the piper wing spars.

Now fill the room up with similar folks as described above that must solve, as a group, the spar problem.

Many good people at the FAA. Then there’s the rest of them…
 
Well just imagine you work for the FAA, not an engineer, halfway to your retirement and are responsible for signing off on an AD for the piper wing spars.

Now fill the room up with similar folks as described above that must solve, as a group, the spar problem.

Many good people at the FAA. Then there’s the rest of them…
It's not that they aren't good people. It is that their skill sets, goals and priorities are not always well aligned with those of the people who build, own, repair, and fly airplanes.
 
Piper’s comments are for the AD that affects taper wings (AD-2024-00033-A). I wonder if they have a similar position on the AD affecting Hershey Bar wings (AD-2024-00008-A)?
 
Wow.

Thanks for posting... that's a great read. Totally the opposite of the NPRM. Piper is really sticking their neck out to protect the fleet; I'm kind of amazed. The NPRM reads like it was written hand in hand with piper, but that was clearly not the case.

Perhaps the most enlightening part was where they cover all 11 aircraft with confirmed cracks. 2 pipeline (in the 80s, they counted those too), 3 ERAU, 2 freight dogs with oversize tires and history of multiple landing gear replacements, 1 on a 15,000 hour scrapyard replacement wing, and the rest with other known damage history or lost logs/ presumed damage history.

I was also glad to see them clarify the compliance costs, as well as call out FAA's nonsense $85/hr shop rate.

How do these things get adjudicated? I know the FAA has to respond to all comments, but they can still do pretty much what they want, right? Will Piper's strong response here carry enough weight to stop or at least change this AD?
Thought I read 6 actual fatigue cracks.

I'm moderately surprised about the push back from piper. Considering the killing they'd make selling new spars. But with the Archer still in production and liability if they don't I guess its not that surprising.

I do agree with piper that the inspections introduced a higher failure probability. I wonder if inspections are made routine if they'd figure out an alternative bolt...like a binding barrel. To keep the threads from chafing upon entry/exist. While still keeping the tight fit.

Bottom line.....ERAU has some questionable things going on over there. They're not the only ones using the pa28 for training. Yet they have half the failures. Hmmmmm
 
I'm moderately surprised about the push back from piper.

They have an interest in squashing the perception that their basic design is somehow unsafe.
 
That perception is already out there

Possibly.

But until I read Piper's response, I was not aware that a similar AD in the late 80s existed that was rescinded. Sounds as if they've been down this road before.

Whatever their reasoning, it's reassuring for me.
 
Piper’s comments are for the AD that affects taper wings (AD-2024-00033-A). I wonder if they have a similar position on the AD affecting Hershey Bar wings (AD-2024-00008-A)?
Both AD's cover the Hershey Bar Wings. The AD's differ in what they do or what they want to accomplish.

AD-2024-00033-A; Piper Aircraft, Inc. Model PA-28 and PA-32 Airplanes; Main Wing Spar Inspection​

Summary​

The FAA proposes to supersede Airworthiness Directive (AD) 2020-26-16, which applies to certain Piper Aircraft, Inc. (Piper) Model PA-28-151, PA-28-161, PA-28-181, PA-28-235, PA-28R-180, PA-28R-200, PA-28R-201, PA-28R-201T, PA-28RT-201, PA-28RT-201T, PA-32-260, PA-32-300, PA-32R-300, PA-32RT-300, and PA-32RT-300T airplanes. AD 2020-26-16 requires calculating the factored service hours (FSH) for each main wing spar to determine when an inspection is required, inspecting the lower main wing spar bolt holes for crack(s), and replacing any cracked main wing spar. Since the FAA issued AD 2020-26-16, the FAA evaluated the reports required by AD 2020-26-16 and determined that repetitive inspections of the lower main wing spar bolt holes for crack(s) and non-crack damage (including deep scratches, gouges, and thread marks) and replacement or modification of the main wing spar should be required, calculated service hours (CSH) should be used instead of FSH to determine times for required actions for each main wing spar, and that certain airplanes should be removed from the applicability and a new airplane model added to the applicability. This proposed AD would require calculating the CSH for each main wing spar; repetitively inspecting the lower main wing spar bolt holes for crack(s) and non-crack damage and taking corrective actions as needed; and replacing or modifying main wing spars at a specified time. This proposed AD would also revise the applicability by removing certain airplanes and adding a new airplane model. The FAA is proposing this AD to address the unsafe condition on these products.

AD-2024-00008-A; Piper Aircraft, Inc. Model PA-28 and PA-32 Airplanes; Main Wing Spar Inspection​

Summary​

The FAA proposes to adopt a new airworthiness directive (AD) for certain Piper Aircraft, Inc. (Piper) Model PA-28-140, PA-28-150, PA-28-160, PA-28-180, PA-28S-160, PA-28S-180, PA-28-236, PA-28-201T, PA-32-300, PA-32R-300, PA-32RT-300, PA-32RT-300T, PA-32-301FT, PA-32-301XTC, PA-32R-301 (HP), PA-32R-301 (SP), PA-32R-301T, PA-32-301, and PA-32-301T airplanes. This proposed AD was prompted by a report of a wing separation caused by fatigue cracking in a visually inaccessible area of the lower main wing spar cap and additional reports of fatigue cracking in the wing spars of airplanes that share common type design features. This proposed AD would require reviewing airplane maintenance records to determine if an eddy current inspection of the lower main wing spar bolt holes was done and, depending on the result, doing a one-time eddy current inspection of the lower wing spar bolt holes for crack(s), and replacing any cracked main wing spar. The FAA is proposing this AD to address the unsafe condition on these products.



PIper included the reports of two Hershey Bar wing PA-32's in their letter/analysis:

1728489386463.png

(16) Serial numbers of the PA-32-300 "E" Models are 32-7240001 to 32-7240147 inclusive (1971-1973 model Cherokee 6's depending on when they rolled off the line)
(17) Serial numbers of the 1973 PA-32-300 Models are 32-7340001 to 32-7340201 inclusive


Piper may have or will submit an additional letter on AD-2024-00008-A
 
Damn! Piper really came out swinging with their response. To my great surprise - Piper actually seems to be sticking their neck out here to defend the fleet of planes from 50y ago! A lot of gems buried in there.

FAA can't be happy to read lines like:
"[FAA] mis-characterize the extent of collaboration between Piper and the FAA... While it is true that the FAA and Piper worked together to determine an inspection program, the FAA rejected the proposals put forth by Piper. Throughout this process, Piper Aircraft has consistently supported the FAA's efforts while formulating a conservative corrective action plan. The FAA requested extensive data and analysis, and Piper delivered countless pages of comprehensive documentation, most of which appears to have gone unused by the FAA"

I think one of the best points I read in there was their refuting the legitimacy of basing the inspection/spar policy based on 1 single, solitary plane.
"It is not appropriate, nor is it rational to base inspection times on a single airplane which will dictate the inspection program for the entire fleet of aircraft in the field"

I also enjoyed a number of their other points based in fact:
- Sytematically looking at each aircraft that had cracks. Pointing out history of heavy modifications/bad landings/ and in 1 case a hangar having previously collapsed on the plane!
- The same reason they withdrew the AD in the 1980s is valid today (maintenance fatigue + cost). Quote: "On May 22, 1989, theFAA made the justified decision to rescind the AD, citing that performing the inspections could damagethe wing spar bolt holes resulting in premature fatigue and failure of the wing spar, and therefore thesafety benefits did not justify the inspection costs."
- $141/hr is a much more realistic shop rate than the FAA's assumed $85/hr
- Why Group1 has a lower starting CSH than Group2 despite Group2 having higher operational loads/stresses
- That CSH could exceed TIS with the FAA calculation, which results in non-sense answer

It all just sort of makes a case that this proposed rule was assembled haphazardly and without a lot of logic, and definitely not in lockstep agreement with the manufacturer.
 
Piper really came out swinging with their response.
You'll find a lot of OEMs will get involved at all levels during the NPRM process. There's a lot at stake in some cases. And even if the regulatory authorities still go ahead with their plans have seen OEMs go the extra mile and pursue alternatives like Global AMOCs to assist owners.

What needs to happen now is ALL Piper owners need to post a comment in the NPRM(s) in support of Piper. It does make a difference.

$141/hr is a much more realistic shop rate than the FAA's assumed $85/hr
For reference the FAA is required to follow a set procedure when determining labor rates per the APA process. So just like any other governmental estimation of costs it usually ends up on the low side.
 
What needs to happen now is ALL Piper owners need to post a comment in the NPRM(s) in support of Piper. It does make a difference.

How would one phrase a comment in support of Piper to be effective?

"I am an owner of a Piper aircraft subject to the proposed AD and object to the FAA's proposal. I have read Piper's response to the proposed AD and feel satisfied that their expert analysis and experience with a previous similar AD shows that the proposed AD is not only unnecessary, but potentially more harmful than doing nothing at all."

Or something similar?

I think when it comes to comments from lay persons, the less verbose, the better.
 
It's not that they aren't good people. It is that their skill sets, goals and priorities are not always well aligned with those of the people who build, own, repair, and fly airplanes.
Yeah. They don’t give a **** about your ability to afford aviation any more than you care about their retirement.
 
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