Menu Sign In Contact FAQ
Banner
Welcome to our forums

Certificate of Conformity

I brought some washes from a well known UK supplier to replace some missing ones from my aircraft cowling. They came with a Certificate of Conformity. Could anyone tell me what this means?

The items conform with the standards required published for the part number and the source of the part can be traced back to the manufacturer who will have put in place quality checks to assure that the parts meet the required standards.

I think strictly speaking it can mean anything that it says it means, or whatever the Quality Manual for the referenced Quality System contains.

For example if in the Quality Manual you state that the item will self destruct after 60 days, that is what you are certifying. This is also applicable for the ISO9000 system, although very few manufacturers would dare put that in there

At work we can print off a CofC (upon request, no charge) which simply states that the product meets its published specification. Everybody is happy with that, and nobody has ever made the most blindingly obvious observation that only a madman will reveal that his product doesn’t meet the published specification We don’t charge for this CofC, but a charge may be made in many other scenarios.

If you want to dig around what a CofC really means, i.e. potentially nothing, read this for example.

In aviation it is usually a certificate of traceability.

Administrator
Shoreham EGKA, United Kingdom

But does that mean it’s fit for aviation use?

I could buy say a brick with a CofC and it doesn’t mean it should be used on an aircraft.

I note that some of the switches for my aircraft come with a CofC and cost 60 quid. Yet identical ones without cost 20 quid. I struggling to see why my one can use the former and not the later.

Please correct me if I am wrong but I think the CofC is a worthless piece of paper. The proper paperwork for aviation items is a form 1 or in the US form 8130. Because that is often not supplied with minor items like washers etc. people start printing CofC but I think that is as good or bad as no paperwork at all. I think some common sense should be applied. Some screws holding the interior and many similar parts do not really need such paperwork but for the screw holding the engine to the airframe or any important part with a serial number I would like a form 1 / 8130…

www.ing-golze.de
EDAZ

As an EASA 145 company the C of C gives us the authority to fit parts , this is much to our customers advantage as if these parts have a C of C from the original manufacturer we don’t have to source these parts from the aircraft manufacturer at an inflated price.

Therefore the C of C is far from a worthless bit of paper, in some cases it has reduced the cost of a part to our customers by 50% and still left us with a reasonable Proffit.

Bathman wrote:

I note that some of the switches for my aircraft come with a CofC and cost 60 quid.

There are no certified switches in aviation. Strange, but true. A switch is deemed “certified” along with the aircraft. This also means there are no design criteria, performance criteria or manufacturing process criteria for switches. A CofC means nothing. It’s only the manufacturer issuing a paper. The manufacturer itself need never to be controlled by anyone. . In other industries, like for instance Oil & Gas and Energy, there is a different system. Here the re-seller of “nuts and bolts” receives a certificate by a national or international certification firm. Purchasing nuts and bolts from these re-sellers, and you are guaranteed to have quality parts (well 99.99 % ). Meaning the parts adhere to the appropriate industry standards

The industry at large, any industry for that matter, doesn’t really care about CofC or anything like that. Boeing or Cessna for instance will purchase directly from the manufacturer. When doing that they will investigate the manufacturer and their product themselves and continuously do so. It’’s only for the after market these things are of some value, and therefore “genuine parts” becomes important. It really is the only way to be reasonably sure that a replacement part is of the same quality as the original part, and that the manufacturer is “approved” by Cessna for instance. The car industry has since long left this nutty system, but it was the norm also there. Today, for reasonable new cars, you will get quality replacement parts everywhere because re-sellers and garages are qualified to sell these parts.

We like to think that a bolt from Aircraft Spruce is a quality item. This is not so. It may or may not be so, and a CofC means nothing. You may get lucky and get a “genuine part” though. Purchasing metric bolts from qualified car garages and/or qualified re-seller, and you are as good as 100% sure you get a quality item, and with no CofC or any other nonsense paper.

As an EASA 145 company the C of C gives us the authority to fit parts

One point worth amplifying is that the CofC / 8130-3 / EASA-1 may well be a legal requirement (per EASA) for accepting the part from the supplier, but it doesn’t in itself authorise its installation.

For example, someone wrote years ago on the US Socata site that if a part comes with an EASA-1 from Socata, it is legal to install on a TB aircraft. That is complete nonsense. The form just certifies that the part is what it says it is, and/or was inspected IAW some spec, etc. Many people – particularly in Europe, with the EASA-1 – think there is an implied suitability for an application, but there is no such thing. PMA, for example, is something else.

There are no certified switches in aviation. Strange, but true. A switch is deemed “certified” along with the aircraft.

That is probably true for most small parts. You probably can’t find a TSOd toggle switch… Also the US has the “standard parts” regime which covers nuts, bolts, nutplates, etc. But these still need to come with a bit of paper, if required in your jurisdiction.

I note that some of the switches for my aircraft come with a CofC and cost 60 quid. Yet identical ones without cost 20 quid. I struggling to see why my one can use the former and not the later.

Ostensibly, traceability i.e. assurance it is not a fake part. It may be blindingly obvious that nobody would fake some obscure item, but…

We like to think that a bolt from Aircraft Spruce is a quality item. This is not so. It may or may not be so, and a CofC means nothing

A CofC may be a legal requirement by the national CAA, as A&C says it is in his case.

Of course the part can still be a fake part. The way this is usually done, certainly in the electronic component business, is this: somebody makes 10,000 of a certain fake chip. It is possibly just an empty package (no silicon inside). He buys 10,000 of the real part, and sends it back for a refund. But he sends back the fake ones. He then sells the real ones somewhere. I’ve had that… it works because the distributors don’t do any testing (or meaningful inspection) on the parts which get returned.

Ultimately, yes, you can get a brick with a CofC. And anyway a CofC (or any “form”) is meaningless for any part which doesn’t have a serial number (or a batch number, at a stretch) printed on it. But that is being practical, not legal

Administrator
Shoreham EGKA, United Kingdom

Ok I see that for an EASA aircraft you need a CofC to fit the part.

What about my N reg aeroplane?

No form needed for Part 91. An FAA A&P has the authority to inspect and declare airworthy.

However, most European based A&Ps, and European based FAR145 companies, don’t know this, or don’t agree with it. In the case of a company supplying a part they have an incentive to source a higher priced part, of course.

Administrator
Shoreham EGKA, United Kingdom
15 Posts
Sign in to add your message

Back to Top