Unauthorized installed equip?

Hi all!

So I've been spending the past few days researching and making calls. Here's what I've been told by AFS 300 tech ops, 2 different people at our local FSDO, and a repair station chief of maintenance in KS city, and in addition, asked for sources.

As it stands, 43 app A HAS ABSOLUTELY NOTHING TO DO WITH PARTS AND THEIR APPROVALS WHATSOEVER, FULL STOP. As I said earlier, it only covers methods and practices. Even in the case of minor alterations, the parts MUST STILL HAVE AN APPROVAL (or meet one of the acceptable cases below).

Now, I did read back over and see a potential point of confusion through all of this: if I'm pulling new wire, or adding cockpit lighting (maybe adding a new light socket), these are minor alterations, as long as the PARTS I AM USING have approvals/acceptable data: like if I have a piper warrior, and I buy another light socket from their parts catalog, then I don't see why this can't be done on just a log entry. It's a piper part that is already installed in the airplane, and I don't see why we can't put another one in there somewhere as long as we don't cross into the major alteration category, like, for whatever reason, riveting it to a spar :p.


Now, back to parts: it is 21.8 and 21.9 that I was told to examine:

Code:
14 CFR 21.8


If an article is required to be approved under this chapter, it may be approved—
(a) Under a PMA;
(b) Under a TSO;
(c) In conjunction with type certification procedures for a product; or
(d) In any other manner approved by the FAA.
Code:
14 CFR 21.9



(a) If a person knows, or should know, that a replacement or  modification article is reasonably likely to be installed on a  type-certificated product, the person may not produce that article  unless it is—
(1) Produced under a type certificate;
(2) Produced under an FAA production approval;
(3) A standard part (such as a nut or bolt) manufactured in compliance with a government or established industry specification;
(4) A commercial part as defined in §21.1 of this part;
(5) Produced by an owner or operator for maintaining or altering that owner or operator's product; or
(6)  Fabricated by an appropriately rated certificate holder with a quality  system, and consumed in the repair or alteration of a product or article  in accordance with part 43 of this chapter.
(b) Except as  provided in paragraphs (a)(1) through (a)(2) of this section, a person  who produces a replacement or modification article for sale may not  represent that part as suitable for installation on a type-certificated  product.
Therefore, by regulation, you cannot install a part, no matter how minor, no matter what kind of work, and no matter what you intend to do, without the part having an approval/acceptance of some kind (disclaimer: or exemption in rare cases :p).


Now, again, lets say you don't fit into any of these categories above. There's two options left: the SUPPLEMENTAL TYPE CERTIFICATE, and the FIELD APPROVAL. Both of these are AUTOMATIC 337s. Therefore, I STILL stand by my claim. Without any other approval, you need a field approval, and thus a 337. In the case of a field approval, this is because the 337 itself becomes the basis of approval.


Now, I will cede the point: people will give me the most conservative answers. That's why I asked for sources to cite. I'm still open to people pointing out where this stuff isn't the case for TCed products, but this time, I would like to be the one to ask for sources, and not just "because I'm an IA that has been doing this for years" (there's enough IAs out there that have been doing it wrong for a long time and got their certificates pulled once they were caught). I feel I've provided enough information and cited sources and advisory circulars for my argument, and I'd rather take the word of three FAA tech ops over random people on the internet :).





Seat belts and harnesses are covered by TSO, and thus becomes a standard part that meets a government spec. That's your "approval" (since you pointed out the word approval is misused, I'm using the term loosely to try and avoid another giant debate).

It also depends on WHICH TSO. I don't remember their exact numbers, but one TSO for seatbelts and seating was pretty basic, while the other had a lot of implications about crash test worthiness and testing when changes are made. I suspect the latter is more for airlines, but that's purely speculation on my part.

Now I saw something about Rosin sunvisors. I doubt there's any issue with these sunvisors going into a plane. Still, that's how it is. If it doesn't have a spec to meet, or PMA replacement part, you can't do it. It's bull, it's a super simple mod (why not just "clip on" a tinted piece of acrylic then and forget the whole STC process) and the regs are a pain in the ass sometimes, but that's how it is.

You best read.

http://www.groveaircraft.com/ac23-27.pdf
 
I've read that AC already. What's interesting to note is it also matters if an aircraft was certified under CAR 3 or the current regs, as that will affect how it's handled too.

If we try to list *every single exception*, the list would be quite long. Since the subject of conversation was a landing light on a 172, I'm sure we're talking about current TC products where part support is still there, not vintage aircraft (although I LOVE the look of straight tail 172s! :))
 
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Back to the original post-

A landing light bolted to the nose gear does not ordinarily meet the definition of a major alteration, therefore it does not require a 337 if a few conditions are met. If the parts used in the alteration are genuine aircraft parts, and are optional for that make & model, and the mechanic installed them with an appropriate logbook entry and amended weight and balance, you are done. If they are AutoZone parts or an HID lamp, you start the STC or Field Approval process.
 
I've read that AC already.

Well then,, tell us when a PMA is not required.

You are repairing a wing, the Spar is a wooden one. Can you manufacturer a new spar for the repair.
 
I recall 43.13 had a lot of stipulations regarding types of wood (sitka spruce is the standard), rules regarding splicing, etc. That's fabrication though for 21.9(a)(5), no PMA required, but it's definitely a major (well, as defined by current regs anyways), depending on if you are replacing or substituting. Again though, vintage aircraft have a few little oddities, and my knowledge of them and how the FAA treats them is weak, and sometimes I feel like they get special treatment :p
 
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Hypothetically, let's say during the course of airplane shopping, you discover that an airplane's mechanic has installed an item that wasn't originally installed (it's recorded in the aircraft logs). For instance, this hypothetical item could be a nose gear taxi light (wing lights were original equipment and are still installed).

I assume this kind of installation would require a Form 337 from the FSDO or an STC in the logs in order to be considered legal?

If this is the case, are there any fees associated with making this installation legal (assuming no STC exists)?

Would you consider this a negotiable item (and at what cost) towards purchase?

Hypothetically of course.

Give it some serious thought before you get it. Field approvals for modifications can be very hard to get. Some FSDO's seem to just automatically say no. I'm assuming the hypothetical is real. Is it negotiable? Only the seller knows the answer to that question. I suppose you could stoop to threatning to turn him into FSDO. If you get it choose your AI well before the next Annual.
 
Give it some serious thought before you get it. Field approvals for modifications can be very hard to get. Some FSDO's seem to just automatically say no. I'm assuming the hypothetical is real. Is it negotiable? Only the seller knows the answer to that question. I suppose you could stoop to threatning to turn him into FSDO. If you get it choose your AI well before the next Annual.

SEA FSDO is not that way. I gain approval on every approval I ask for. You simply must know what to ask for and what data to provide.
 
I recall 43.13 had a lot of stipulations regarding types of wood (sitka spruce is the standard), rules regarding splicing, etc. That's fabrication though for 21.9(a)(5), no PMA required, but it's definitely a major (well, as defined by current regs anyways), depending on if you are replacing or substituting. Again though, vintage aircraft have a few little oddities, and my knowledge of them and how the FAA treats them is weak, and sometimes I feel like they get special treatment :p

""Manufactured and installed new left Spar IAW the Fairchild blue print #4097""

Log book only entry and no PMA. manufacturing parts as they were manufactured in the day, is not a major, they are treated as a part replacement.
Many of the Cessna skins have a part number in the IPC, with the note " manufacture from .016" 2023-T3" they can be manufactured in the field and used in repairs with no PMA or field approval.
Simple parts replacement is not a major alteration or modification. Although these parts may be used in major Repairs that require a field approval.
 
But, I never claimed that PMA was the only way :). PMA was one of the items, but not the only items, in which you could install a part without the 337 :). I pointed out "during the course of repairs" as another way in my post :)

By the way Tom, thanks for not jumping all over me and taking the time to engage with me maturely. I like the way you get people to research, and the way you form your responses seems like you're willing to even listen to greenhorns in case we make a good point :)
 
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SEA FSDO is not that way. I gain approval on every approval I ask for. You simply must know what to ask for and what data to provide.

That's good to know. Portland FSDO seems to have a terrible reputation about field approvals. I was looking into do something a few years back and the people I talked to who had experience said to do that, the FSDO in Alaska is probably going to be your only chance.
 
That's good to know. Portland FSDO seems to have a terrible reputation about field approvals. I was looking into do something a few years back and the people I talked to who had experience said to do that, the FSDO in Alaska is probably going to be your only chance.

I wonder how many of these folks actually followed the AC 43-210. Or did they simply send a 337 in for approval, with no data for the ASI to determine the airworthiness of the change/mod/alteration.
I will normally call my PMI and discuss the project, find out what he wants to see, ask where to find it, and what is acceptable.

then compose the cover letter with in those boundaries, and submit it, some time the ASI will return the paper work for corrections, but that will get done and resubmitted.

Eventually I get it approved. Longest turn around has been 3 months, due to non FAA reasons.
 
By the way Tom, thanks for not jumping all over me and taking the time to engage with me maturely. I like the way you get people to research, and the way you form your responses seems like you're willing to even listen to greenhorns in case we make a good point :)

I try to not to be condescending, and steer the response to guide. but some times it just doesn't come across that way.

and then there are the ****oles that simply don't understand what they read. :)
 
and then there are the ****oles that simply don't understand what they read. :)

It is often a refusal to understand, not a simple failure to understand.
 
It is often a refusal to understand, not a simple failure to understand.

Having worked IT in the past, that's it right freaking there.

Hey is that a Sky Arrow by the way? I might have to poke FastEddieB too :p.
 
My avatar is a Earthstar Odyssey with a Hirth 3203, and it now belongs to a good friend of mine. My current planes are a Pioneer Flightstar with a 503, and a highly customized Spitfire 2 with a Rotax 670.
 
I wonder what the FAA does with those 337s?:dunno:

I have not seen this written down, but I have run into the discussion before with airline policy.

The vast majority of the entries in a log book typically do not capture changes to the FAA approved data. The 337s do.

If the FAA wants to see the documents that define the approved configuration of an airplane, they probably don't want to go through 30 years of log book entries.

With 337s on file (hopefully) they have a record of the TC and a complete record of all Major Alterations and Repairs that might have altered the TC.

(I revised to reword this post)
 
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All modifications which involve the installation of parts* which are not based on approved data (approved data being PMAs with appropriate sections stating what it can be installed on or replace, TCDS, STCs, DER Engineering data, field approvals, etc) or installed during the course of repairs (and such repairs are not major IAW 43 APP A) require a 337. This light is no exception.

A PMA does not approve the installation of a part on any given airframe.

A PMA approves that a part is manufactured under sufficient controls acceptable to an FAA MIDO to be considered an airplane part. Some other process determines if a part is approved for installation on any particular aircraft. Often the approval for installation is an STC.
 
A PMA does not approve the installation of a part on any given airframe.

A PMA approves that a part is manufactured under sufficient controls acceptable to an FAA MIDO to be considered an airplane part. Some other process determines if a part is approved for installation on any particular aircraft. Often the approval for installation is an STC.

I know this. That's why it's part of a list of items.

As I understand, some PMA parts are direct replacement, and can be installed based on said PMA only.
 
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I believe there's two categories in part 21, PMA with OEM intellectual property and PMA when there isn't. It should be easy to find, I'm typing from memory.
 
All modifications which involve the installation of parts* which are not based on approved data (approved data being PMAs with appropriate sections stating what it can be installed on or replace, TCDS, STCs, DER Engineering data, field approvals, etc) or installed during the course of repairs (and such repairs are not major IAW 43 APP A) require a 337. This light is no exception.

Now, what does this mean? Well, you can either have the light removed, get the installation inspected and approved, or ignore it and hope nothing turns up.

*Parts are things that are NOT:
hardware (bolts, nuts, clamps, etc)
hosing & tubing
wiring and connectors
other components which are only required to meet a spec
All of the above must also avoid being in contravention to manufacturer mx instructions, or it will require the 337 and approved supporting data.

Id go with that answer.

As part of the sale, Id ether want the owner to get a 337 for the light, or I'd want the light and all the mounts, wires, etc gone at owners expense.
 
I'll say it again. What your teachers had to say to keep the FAA off their tails and what happens in the real world sometimes differ by a bit more than an RCH. They probably didn't teach you that acronym either; see what I mean?
Jim


My dad used that one a lot.

Thanks for the memories.
 
You are right about one thing though, it is getting worse and it's not because people are dropping out of the sky with "unapproved" landing lights strapped to their gear leg, it's because everyone seems to have developed this inexplicable fear of their own shadow and are focused on nothing else 24/7 other than trying to cover their own ass.

It's truly sad - don't become one of them, have some faith in yourself and come to the understanding that AC 43-13-2B - Acceptable Methods, Techniques, and Practices - Aircraft Alterations is there for a reason

Liability and cost. Will the revenue (let's say 2 x $500 installations, less part cost nets $250 to the mechanic) offset the cost of dealing with potential FAA investigations, suspensions, insurance issues, etc? It's that way in a lot of industries - even if you "win" you lose.

There's an old saying "You can beat the rap, but you can't beat the ride". The system is structured in a way that the potential cost of doing something that might raise a question is often higher than the value to you of actually doing it. You will be assimilated.

And this is not just limited to aviation - there are plenty of settlements that are done in the business world just because it's more costly to let it go to trial than to settle. Class actions, too. Attorneys know this, and often set settlement terms to be a bit less than the estimated cost of trial. There's a reason that most every company pushes for arbitration - cell phones, credit cards, cable, telephone, you name it, etc.
 
In the case of an hypothetical landing gear light installation.
(a) Major alterations—(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:

(vi) Landing gear.

(xii) Changes to the basic design of the . . . , electrical, . . . systems.

If you have no approved data (an STC) and no acceptable data (OEM IPC, AMM or Service Bulletin), SBs may or may not be FAA approved:

I think that bolting something on the landing gear could reasonably be viewed as a major.

I also believe that changing the loads on an aircraft electrical system could reasonable be viewed as a major change to the basic design of the electrical system. Is there now an electrical fire hazard on the airplane? Did anyone do an electrical load analysis?

The simplest thing to do is probably take the thing off.
 
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I believe there's two categories in part 21, PMA with OEM intellectual property and PMA when there isn't. It should be easy to find, I'm typing from memory.

It was bugging me to find this again. FWIW, it's referenced in 21.303 and elaborated on in AC21.303-4.


AC 21.303-4
[FONT=&quot]1. [/FONT]How to Submit an Application.

a. Apply by letter to the ACO or MIDO in the geographic area of your manufacturing facility depending on the basis of your PMA. The FAA may reassign review of your application to another ACO or MIDO at its discretion. See appendix F for ACO addresses. Use appendix B, PMA Application Checklist, as an aid to your application. The following guidance assumes that the listed supporting data is complete at the time of application. However, use a Part Specific Certification Plan (PartSCP) and discussions with the project ACO to schedule significant showings of compliance and associated test reports.

b. If your PMA basis is identicality with a license agreement or STC, see AC 21-43 and Order 8120.22 for further guidance.

c. If the PMA basis is identicality without a license agreement, show the design of your replacement article is identical to the design of an article approved under a type certificate. Identical means the same in every respect including dimensions, tolerances, processes, etc. Provide sufficient data to show your design is identical. Send this application and supporting data to the geographic ACO.

d. If the PMA basis is test reports and computations, send the application letter to the geographic ACO. Test reports and computations employ two strategies to show compliance with applicable airworthiness requirements for eligible products: general analysis and comparative analysis. This AC provides guidance on each of these strategies and aids you in providing the necessary data to show compliance with the appropriate airworthiness requirements.
 
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...I think that bolting something on the landing gear could reasonably be viewed as a major...

Okay, so then how do you feel about bolting something like this onto the flight control yoke?

ipadyoke1.jpg


Because the same argument can be made, you can't have one without the other and while we're at it show me the PMA stamp on that mount :dunno:
 
Okay, so then how do you feel about bolting something like this onto the flight control yoke?

ipadyoke1.jpg


Because the same argument can be made, you can't have one without the other and while we're at it show me the PMA stamp on that mount :dunno:

I always laugh a little inside when I see a cockpit like that.
 
Okay, so then how do you feel about bolting something like this onto the flight control yoke?



Because the same argument can be made, you can't have one without the other and while we're at it show me the PMA stamp on that mount :dunno:

The FAA doesn't consider temporary mounting, including bolting clamps AROUND (but not through) the yoke, as an installation in part 91 aircraft (as long as it doesn't interfere with operation either).

Same with suction cupped cameras on the aircraft (thought they will hold you accountable if it falls from the plane and hits someone or causes a problem with the plane itself).

Unfortunately I don't have that source for you now as it's been a long time since I read that one (couple years maybe?), but it was in an official release as there was a lot of back and forth about it and finally the FAA went "we'll allow it, but you're still responsible".
 
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So Why are you making the assumption that the hypothetical landing light is bolted "through" or interferes with operation?
 
In the case of an hypothetical landing gear light installation.
(a) Major alterations—(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:

(vi) Landing gear.

(xii) Changes to the basic design of the . . . , electrical, . . . systems.

If you have no approved data (an STC) and no acceptable data (OEM IPC, AMM or Service Bulletin), SBs may or may not be FAA approved:

I think that bolting something on the landing gear could reasonably be viewed as a major.

I also believe that changing the loads on an aircraft electrical system could reasonable be viewed as a major change to the basic design of the electrical system. Is there now an electrical fire hazard on the airplane? Did anyone do an electrical load analysis?

The simplest thing to do is probably take the thing off.

So,,, tell me again, how was the landing gear modified or altered? did they drill a hole in it? weld some thing to it? bend some thing? How was the gear modified?

Unless the light changes the landing gear, or its operation, the landing gear is not modified. the light is simply a added circuit to the electrical system. that may or may not be a modification to the electrical system, depending upon how it was done.
 
So Why are you making the assumption that the hypothetical landing light is bolted "through" or interferes with operation?

I was referring to cockpit mounted stuff for bolting clamps.

As for external mounting, that landing light ties into the electrical system. That's not a temporary installation :p.
 
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I was referring to cockpit mounted stuff for bolting clamps.

As for external mounting, that landing light ties into the electrical system. That's not a temporary installation :p.

Now you use terminology that the FAA does not use in describing what repair/modification/alteration.
 
This field request is to certify an alteration that was installed by people or persons unknown by this facility.
This aircraft has flown XXXX number of hours since any major maintenance was logged in the history records with no problems in any mechanical system.

All info found in block #8, of the 337 in this package.

Sincerely request approval.

Your Happy A&P
@ the Hangar.
 
Now you use terminology that the FAA does not use in describing what repair/modification/alteration.

Sorry, temporary mounting :D. I did find this memo using that language. This isn't the one I'm looking for, but it does have some... interesting wording!

http://www.avweb.com/blogs/insider/FAA-camera-memo.php

EDIT: Here's another AC on EFB mounting for Silveraire. It has a lot of recommendations regarding EFB mounting, including specific mentions of yoke stuff and how the FAA feels about it. http://www.paperlesscockpit.com/wp-content/uploads/2011/11/AC-20-173.pdf
 
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So,,, tell me again, how was the landing gear modified or altered? did they drill a hole in it? weld some thing to it? bend some thing? How was the gear modified?

Unless the light changes the landing gear, or its operation, the landing gear is not modified. the light is simply a added circuit to the electrical system. that may or may not be a modification to the electrical system, depending upon how it was done.

Is bolting or strapping a device onto a part of the airplane a modification? I'd say probably Yes. You can't bolt something on to a control surface either.

If the answer is yes, it's a Major Alteration. Is it a Major alteration that could probably be approved by a person that has the appropriate approval authority? A DAR or the FAA could probably review the Part 23 requirements for landing gear, approve whatever testing is needed, and if the data shows it meets all the requirements approve it as a Major Alteration.

Hypothetically (yes we are still deep in that) , suppose the addition of the light and fixture prevented full emergency extension because of the added aerodynamic loads?

It's a little different for the electrical aspect of the installation. I saw the statement that the Electrical Load Analysis is within limits on a lot of the 337s for my own airplane. I spent the $50 for a copy of ASTM F2490 − 05, Standard Guide for Aircraft Electrical Load and Power Source Capacity Analysis. Apparently the FAA paid the ASTM to develop the spec. After reading it I personally believe very few GA Mx folks know how to perform an acceptable ELA too.
 
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So Why are you making the assumption that the hypothetical landing light is bolted "through" or interferes with operation?

What is your basis for making the claim that it does not? The question is, does it still meet all the Part 23 Certification requirements that could be affected?
 
I was referring to cockpit mounted stuff for bolting clamps.

As for external mounting, that landing light ties into the electrical system. That's not a temporary installation :p.

So does the iPad and the Garmin and the Sirius and the...

It seems that you are bound and determined to prove that this hypothetical landing light is illegal, that it can't possibly be legal but the documents you are using to support that contradict it. You seem to be saying it's perfectly okay if it's a GoPro, it just can't be a landing light.

A quote from the link you provided above addressing a question on external mounts for cameras:

Because of the varying installation possibilities of this equipment, the major vs. minor determination is done on a case-by-case basis and made by the installer. Major alterations are those that have an appreciable effect on the weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness. If the installation did affect one of the the above listed variables, then the installation would be considered major and would require approved technical data prior to returning the aircraft to service.

I think you also need to understand a fundamental aspect of all of this that you seem to be missing. "determination is done on a case-by-case basis and made by the installer" In this hypothetical case there is a logbook entry made by the A&P for the installation of this landing light. It was determined to be a minor alteration and basically that's it. Dragging all of these documents out concerning PMA and TSO that do not apply is an exercise in futility. Nobody is asking to manufacture replacement aircraft parts here such as gear legs or door handles. As an A&P you have acquired the license, the responsibility and the authority to make specific decisions. You don't need to have the local FSDO on speed dial to call every time you want to do that. It's your right to refuse to make such an installation if you chose, even to refuse to sign of an annual if that's the way you want to go about it but you need to lighten up a bit.
 
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What is your basis for making the claim that it does not?...

Because it's a hypothetical question and in my hypothetical it doesn't. You can't counter that with "yea, but what if it does?"
 
Plenty of consumer electronics out there in certified aircraft these days. One example:

Things that I see

#1 The IPad
#2 The AOA, I highly doubt is STC or PMA in any way.
#3 I question the make/model of the standby horizon as there are many that hold no approval.
#4 What the heck is below #3?
#5 Is there an existing approval for that Airpath compass in that make/model airplane? Was it calibrated using a compass rose that has a current survey?


AOPA...

 
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#1 The Garmin Area
#2 The Garmin Area Antenna
#3 The ampmeter looks questionable
#4 That looks like the cheapo Davtron M800 clock I installed last year in a friend's airplane. No PMA for Cessna, no STC but it did come with a letter from the FAA stating that replacement clocks in non-transport category aircraft can be completed as a minor alteration.
#5 Where is the compass? What make model is it? Is it approved for Cessna 152? Was it calibrated using a compass rose that has a current survey?


 
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In my experience an owner may use optional electronics as long as approved primary instruments are installed. However, one of the most difficult field approvals I know of was for adding landing and taxi lights on my Cub's gear. We had to negate any potential for light reflecting on the back side of the prop.
 
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