Need Gear Pucks

[thomas1142]

https://avunlimited.co/
 

Has anyone used this company for landing gear disks? It’s based in South Africa and it sees they “build” the disks as required, like an owner supplied part.

Angelos

[carusoam]

@gummirat

was getting closer to being able to supply donuts for the Mite community…

He has rubber manufacturing skills to make a decent donut to meet OPP specs…

LORD needs competition…

Go capitalism!

Best regards,

-a-

[buddy]

I wish I saw this 2 wks ago, Chief aircraft was 1K more for 11. Mine are already installed.

[201Steve]

Varma

[thomas1142]

9 hours ago, buddy said:

I wish I saw this 2 wks ago, Chief aircraft was 1K more for 11. Mine are already installed.

Current price at Aircraft Spruce is $230 each. Crazy!

[Utah20Gflyer]

I’m a little confused about the recent FAA memo issued about being able to use off the shelf parts for aircraft approved before 1980 but the seemingly contrary action they took against owner produced down lock blocks.  If you can buy an off the shelf part then why can’t someone make a part and sell it to someone else and skip the approval process?   Why no approval process for a wheel bearing but you do need approval for a down lock block?  Neither is a critical component.  Seems like there is far too much grey area.   Unclear regulation with selective enforcement is probably the worst situation possible.  

[PT20J]

1 hour ago, Utah20Gflyer said:

I’m a little confused about the recent FAA memo issued about being able to use off the shelf parts for aircraft approved before 1980 but the seemingly contrary action they took against owner produced down lock blocks.  If you can buy an off the shelf part then why can’t someone make a part and sell it to someone else and skip the approval process?   Why no approval process for a wheel bearing but you do need approval for a down lock block?  Neither is a critical component.  Seems like there is far too much grey area.   Unclear regulation with selective enforcement is probably the worst situation possible.  

I believe the crackdown started because of a problem that surfaced with counterfeit parts — usually structural bolts that weren’t. I believe there was an airline crash where the bolts attaching the vertical tail failed and the NTSB determined they were counterfeit. This led to increased FAA scrutiny of proper documentation and approvals for all aircraft components.

[Joshua Blackh4t]

I contacted them 6 months ago and they said its still in development with no eta of when available. Also, $80+$20 shipping each which doesn't go down when ordering a set.

But its a lot more reasonable price. I'll be trying a set when they come available.

If they could also make an intake boot I'd also pay to Owner Produce one of them as well.

 

[Utah20Gflyer]

10 hours ago, PT20J said:

I believe the crackdown started because of a problem that surfaced with counterfeit parts — usually structural bolts that weren’t. I believe there was an airline crash where the bolts attaching the vertical tail failed and the NTSB determined they were counterfeit. This led to increased FAA scrutiny of proper documentation and approvals for all aircraft components.

This isn’t really the issue I am confused about.  I think everyone is in the same page with counterfeit parts that will kill you or a lot of other people if they fail.  I’m referring to something like the owner produced down lock blocks or these landing gear pucks which seemingly fall under owner produced parts or vintage aircraft parts yet the FAA issues letters saying people are selling unapproved parts and they shouldn’t be installed in airplanes.   If someone produces an owner produced down block which the FAA seemed to believe didn’t qualify as an owner produced part, why would that matter if it was a vintage aircraft?   According to their latest memo some parts don’t have to be approved so why are they issuing letters saying don’t install them? Hopefully this makes more sense. 
 

These landing gear pucks don’t need to be approved based on what I think the vintage aircraft memo said but is the FAA going to issue a letter in a couple months saying they are selling unapproved parts and they shouldn’t have been installed into an aircraft? 

[EricJ]

All parts that go on an aircraft need to meet the specifications for that part and be safe for installation.   Not every replacement part will meet those criterion, and sometimes it is a little difficult to tell whether a part fully meets the requirements or not, which is often where disputes about can or can't come from.

The landing gear pucks need to be essentially equivalent or better than the originals, which suggests characteristics like durometer, density, etc., and the ability to survive the environmental effects of sun, rain, oil, brake fluid, fuel, etc., etc., make a difference.   Somebody pouring polyurethane of unknown characteristics into a mould isn't sufficient.

This is the gist of the OPP process, to determine and document that the part is properly duplicated with the correct characteristics and quality check.   Some think this means a part must be identical in every way and should start from the manufacturer's drawings, etc., and others are more pragmatic about making a safe, usable part.

For non-approved (e.g., non-PMA) parts purchased off-the-shelf somewhere, the easy example confirmed at our local IA seminar by an FAA rep was that two parts from the same manufacturer with the same part number in two boxes, one with FAA-PMA stamped on it and one not, the one without the PMA stamp can be used.    The caveat was just that the part needs to meet the relevant specifications of the original part.   Again, this is not always easy to determine, but if you can, then you can use the equivalent part whether or not it is "approved" with a PMA stamp or other qualification.

None of these concepts are new.   The Advisory Circulars that describe the processes and requirements have been around for a long time, but there is always variety in interpretation of them.  There is not any new ruling or interpretation that suddenly allows someone to put a part on an airplane that doesn't meet the required specs.    What "required specs" means is really where the disagreements come in.    For most people the only opinion that matters is their IA's.

[RobertGary1]

I’m also confused and apprehensive. The faa just sent that letter about Mooney unapproved parts made as owner produced. This seems like the same. 
There is no way for an owner or a&p to know if these have the same quality. I can just imagine if the failure mode were chucks break off of it. I’d be too afraid to try it. In fact knowing these guys existed I just bought a full set for Spruce 

[PT20J]

To be a true OPP the owner has to take an active role in its creation. The FAA has a list of acceptable activities. I don’t think having the producer send you a drawing to sign and return meets the requirement, but I not an attorney. 

[carusoam]

18 hours ago, thomas1142 said:

Current price at Aircraft Spruce is $230 each. Crazy!

At this price….

We are going to see Many Mooneys sitting on old donuts that are out of spec…

I’m pretty sure we can follow the OPP guidelines and produce an equivalent part… a whole lot easier than the other parts that have been successfully made via OPP guidelines…

I would like to see a set of donuts well under an AMU… so it doesn’t ring alarms with the finance administrator…. 

 

How re-usable are the steel(?) washers that they all come with?  Are we all tossing out a set of expensive washers with that too?

PP thinking out loud only…

Best regards,

-a-

[MikeOH]

17 hours ago, Utah20Gflyer said:

Unclear regulation with selective enforcement is probably the worst situation possible.  

Ah, the FAA must be incredibly proud to have accomplished their goal

[Cruiser]

original Mooney equipment removed from an 1999 M20S in error (the mechanic didn't read the rule correctly. ) These main gear disks were in spec as removed.
see attached image. 
let me know what you think.

[carusoam]

@Cruiser how many years do they have on them?

They don’t appear to be very compressed at all…

LBs have a tendency to compress the donuts more than SBs…

Best regards,

-a-

[carusoam]

On 5/12/2023 at 9:35 AM, thomas1142 said:

https://avunlimited.co/
 

Has anyone used this company for landing gear disks? It’s based in South Africa and it sees they “build” the disks as required, like an owner supplied part.

Angelos

Oddly,

That seems to have the contact @Gert…

A long term member we have been talking with about this project for years…

His current advertised price is $80 per donut…

Anyone want to ask about availability?

I haven’t spoken with Gert lately…

Best regards,

-a-

[kortopates]

original Mooney equipment removed from an 1999 M20S in error (the mechanic didn't read the rule correctly. ) These main gear disks were in spec as removed.
see attached image. 
let me know what you think.

the other concern is how quickly they re-expand after being uncompressed. If you jack the plane up and after a few minutes you can still twist the disks around they need replacing.


Sent from my iPhone using Tapatalk

[N201MKTurbo]

14 minutes ago, kortopates said:

the other concern is how quickly they re-expand after being uncompressed. If you jack the plane up and after a few minutes you can still twist the disks around they need replacing.


Sent from my iPhone using Tapatalk

Temperature has a huge affect on that. Here in AZ in the summer, the oldest stiffest disks will pass, on a cold winter day brand new ones may fail.

[ArtVandelay]

What’s the life expectancy of pucks?
Both installed and if stored?

[Pinecone]

Not trying reopen the can, but the case of the down locks, the company that made them, sent them out with the drawing, not getting a signed or updated drawing from each owner.  SMALL detail, but does not meet the letter of the law.  McFarland sends a drawing, that the owner adds the lengths or has the owner send the old one to be be duplicated.

So for the pucks, XYZ cannot make them and market them as meeting the requirements and sending out the drawings.  They could say they make pucks, send your specs and we will tell you if ours meet those specs.  The specs could be available online, like here on MS.  I send those specs, they say they meet them and sell them to me.

The other way the owner can "participate" is to do QC/QA on the part.   Which seems was done on the downlocks, but that was not clear to the FAA.  Maker sends part, says we made what we think you asked for, you need to confirm it is correct.

[Sabremech]

57 minutes ago, Pinecone said:

Not trying reopen the can, but the case of the down locks, the company that made them, sent them out with the drawing, not getting a signed or updated drawing from each owner.  SMALL detail, but does not meet the letter of the law.  McFarland sends a drawing, that the owner adds the lengths or has the owner send the old one to be be duplicated.

So for the pucks, XYZ cannot make them and market them as meeting the requirements and sending out the drawings.  They could say they make pucks, send your specs and we will tell you if ours meet those specs.  The specs could be available online, like here on MS.  I send those specs, they say they meet them and sell them to me.

The other way the owner can "participate" is to do QC/QA on the part.   Which seems was done on the downlocks, but that was not clear to the FAA.  Maker sends part, says we made what we think you asked for, you need to confirm it is correct.

You don’t know all the facts in regards to the downlock blocks. Please stop acting as you do. The friendly aviation administration has not replied to my response and subsequent questions to them challenging their assertions from June of last year. I don’t know where this stands with them, but do know that I’m disputing their claims. If and when this is resolved, I’ll be happy to give you all the details so you can be informed instead of posting your personal opinion. I don’t mean to be rude, but these comments are irritating when I and a few others know the facts. 
David

[Pinecone]

10 hours ago, Sabremech said:

You don’t know all the facts in regards to the downlock blocks. Please stop acting as you do. The friendly aviation administration has not replied to my response and subsequent questions to them challenging their assertions from June of last year. I don’t know where this stands with them, but do know that I’m disputing their claims. If and when this is resolved, I’ll be happy to give you all the details so you can be informed instead of posting your personal opinion. I don’t mean to be rude, but these comments are irritating when I and a few others know the facts. 
David

I am just pointing out, that based on what has been posted, I can see the FAA stance.  But also, that it met the requirements, but it was an optics issue.

[N201MKTurbo]

Getting a PMA and the notorious down lock blocks have nothing to do with each other.

[BenT]

I emailed them a few days ago and have not heard back.  Did you get a response/buy them?  Know of any other supplier than Lord?