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EASA Minor v. Major mod versus FAA Minor v. Major mod comparison

A search on e.g.
minor AND major
digs out various threads.

However, let’s take an actual example.

Fred is G-reg and wants to install a backup oil pressure gauge. It would comprise of a T-piece, and a transducer and an indicator. The transducer and indicator are TSOd and obtainable with an 8130-3 which is generally accepted for a new item.

Fred asks his shop regarding the approval. He is told (EASA 145 shop) that only EASA itself, or an EASA 21 company has the authority to decide whether this is a Minor mod. (This was later confirmed by an EASA 21 company, who said they have some limited discretion to do Minor mods without asking EASA).

Fred contacts EASA and gets an arrogant patronising pompous guy (a Brit actually, presumably living in Cologne) who dismisses his arguments with “it’s a different world now”. Probably a “new” individual since I recall reading an article by @bookworm about his project installing vortex generators, which IIRC he did entirely directly with EASA.

So Fred contacts an EASA21 company regarding doing the design. When the quote reaches a few k, he gives up.

Joe is N-reg and wants to do the same. The FAA provides a Minor v. Major decision flow chart, etc. An A&P has the authority to interpret this. Based on this (not a “basic change to…” etc) it is decided to be a Minor Alteration and is installed and signed off by the A&P. The sad fact that the majority of A&Ps won’t stick their neck out on Minor mod decisions just means you need to choose your A&P with care – for his intelligence primarily.

IF the A&P’s decision was that it is a Major Alteration, the options are

  • a Field Approval – requires FSDO interaction
  • an 8110 design package from a DER – no interaction with the FAA
  • an STC – pointless for a one-off

The 1st option is free of FAA fees but risks encountering a “knucklehead” FAA inspector (this term was used by a now retired FAA inspector when describing some of his colleagues, and I am sure rogue inspectors are present in both FAA and EASA equally) BUT you have the option of using a different FSDO, whereas there is only one EASA.

The 2nd option can be expensive but there is/was a US DER firm which used to approve stuff for $300 per sheet. The applicant had to do all the design work. They however never responded to any direct approaches; they worked only with avionics shops. But the point is that if an individual can do the design work, and a backup oil pressure gauge is pretty simple, it need not be expensive to get the 8110.

However if Joe wants to sell his plane to Europe and the buyer wants to register it locally, the options are

  • the installation has to be recertified by an EASA 21 company (four figures)
  • the installation is ripped out

Which bits of the above have changed in recent years?

Administrator
Shoreham EGKA, United Kingdom

Peter wrote:

IF the A&P’s decision was that it is a Major Alteration, the options are

a Field Approval – requires FSDO interaction
an 8110 design package from a DER – no interaction with the FAA
an STC – pointless for a one-off

I’m know you know this but to be clear: In all (FAA) cases, a Major Alteration requires Approved Data to be submitted to the FAA with a Form 337… AIUI A Field Approval can’t just be granted by an FSDO because he inspects it and sees that it’s good for example….they need DAR approve the data…

Approved Data can come from a number of sources:

1. Type Certificate Data Sheets

2. Aircraft Specifications

3. Supplemental Type Certificates (STC’s) (Note: Persons interested in using an STC must have approval in accordance with 49 U.S.C., section 44704, from the holder of the STC prior to it’s use.)

4. Airworthiness Directives (AD’s)

5. Manufacturer’s FAA Approved Data (DOA)

6. Designated Engineering Representative (DER) Approved Data With FAA Form 8110-3, Statement of Compliance (Note: This type of data usually requires additional approval.)

7. Designated Alteration Station (DAS) Approved Data

8. Appliance Manufacturer’s Manuals (Excluding Installation Instructions)

AC 43.13-1, Acceptable Methods, Techniques, and Practices (Aircraft Inspection and Repair), may be used directly as approved data (for repairs only) without further approval only when there is no manufacturer repair or maintenance instructions that address the repair and the user has determined that it is:

• appropriate to the product being repaired;

• directly applicable to the repair being made; and

• not contrary to manufacturer’s data.

This data may also be used as a basis to gain FAA data approval for major repairs.

FAA FIELD APPROVAL (FAA FORM 337) issued for duplication of identical aircraft may be used as approved data only when the identical alteration is performed on an aircraft of identical make, model, and series by the original modifier. FAA Form 337’s info. approved in 1955 or earlier may be used as approved data.

From FAA Order 8300.16:

e. An alternative to a field approval is approval of all the data by a DER or ODA.
Last Edited by AnthonyQ at 27 Jan 06:13
YPJT, United Arab Emirates

I’m know you know this but to be clear: In all (FAA) cases, a Major Alteration requires Approved Data to be submitted to the FAA with a Form 337…

For a Field Approval or an STC, yes.

For the DER 8110 route, no. You just send off the 337 for filing, with the 8110 and supporting data. The DER generates the data – he has the authority. Roughly speaking, an FAA DER is the equivalent of an EASA 21 but the subsequent process is different in that he has the final word, generally. Nothing goes to the FAA. This method has been used by various European shops for FAA mods because the NY IFU (which is/was responsible for Europe) has been dysfunctional for many years.

AIUI A Field Approval can’t just be granted by an FSDO because he inspects it and sees that it’s good for example….they need DAR approve the data…

No DAR is needed. See e.g. here and here

Administrator
Shoreham EGKA, United Kingdom

Peter wrote:

Fred is G-reg and wants to install a backup oil pressure gauge. It would comprise of a T-piece, and a transducer and an indicator. The transducer and indicator are TSOd and obtainable with an 8130-3 which is generally accepted for a new item.

Correct.

Peter wrote:

Fred asks his shop regarding the approval. He is told (EASA 145 shop) that only EASA itself, or an EASA 21 company has the authority to decide whether this is a Minor mod.

Correct. There are different levels on Part 21 authorisations though.

Peter wrote:

Fred contacts EASA and gets an arrogant patronising pompous guy (a Brit actually, presumably living in Cologne) who dismisses his arguments with “it’s a different world now”.

This statement doesn’t add ANYTHING too the discussion. There is no need to contact anyone within EASA. You could just apply for a minor change in this case.

Peter wrote:

So Fred contacts an EASA21 company regarding doing the design. When the quote reaches a few k, he gives up.

Sure if you have them done this kind of work, and work out all details, make drawings etc, it will be expensive. This wouldn’t be different if you would hand everything over to a DER, which basically does the FAA Part 21 work, just like the EASA Part 21 company. They will spend some time on it, review everything and issue you a invoice for the work they do.

If Fred had issued the order I want a backup instrument to his maintenance company, they would very likely have arranged everything for you. These companies know the system and how to deal with it. Sure you can do them yourself, you must be willing to spend some time on it. The same applies to the FAA system.

Peter wrote:

An A&P has the authority to interpret this. Based on this (not a “basic change to…” etc) it is decided to be a Minor Alteration and is installed and signed off by the A&P. The sad fact that the majority of A&Ps won’t stick their neck out on Minor mod decisions just means you need to choose your A&P with care – for his intelligence primarily.

Basically this is the same with EASA.

Peter wrote:

The 2nd option can be expensive but there is/was a US DER firm which used to approve stuff for $300 per sheet.

How can you approve for a fixed fee per sheet??? Some problems are much more complex then others.

Peter wrote:

But the point is that if an individual can do the design work, and a backup oil pressure gauge is pretty simple, it need not be expensive to get the 8110.

That’s why I would be very sure that you can get this approved as minor change under EASA. If it wasn’t an extra indicator, but another P/N replacing the defective one with another P/N, that would be covered under CS-STAN.

Peter wrote:

However if Joe wants to sell his plane to Europe and the buyer wants to register it locally, the options are

the installation has to be recertified by an EASA 21 company (four figures)
the installation is ripped out

This is not true. The installation either has to be undone or recertified, this could be done with excisting approvals or getting a new approval for it. Why should they need an Part 21 company? Only if it was considerd as major under FAA as well….

Lets review the other side. Fred has found a Part 66 who understand the systems, the equipment comes with right paperwork, so can be installed. His engineer applies for a minor change, and it gets approved as minor changes as additional indicator. Fred now wants to change his registration to N-Reg. Now these people at the FAA don’t even accept this changes, it needs to be reviewed again (similair as to go from N-Reg to EASA-Reg).

So where is the difference? So what makes these EASA guys idiots and FAA supperior? They both want to review modifications before they accept them.

Ok, so your tired of your piston engine, and you decide to buy an Soloy engine. You would need an STC for that, under FAA or under EASA. If you would change from EASA to FAA or from FAA to EASA it needs to be reviewed again. No change for that.

So you want to replace your KX-155A by a KX-165A, you woudn’t need an STC for that under FAA, neither would you under EASA. However if you change from EASA to FAA or the other way, it has to be reviewed again.

Ok you want to upgrade exterior lights by LED, you wouldn’t need an STC for that under FAA, neither would you under EASA.

Peter wrote:

Roughly speaking, an FAA DER is the equivalent of an EASA 21 but the subsequent process is different in that he has the final word, generally.

This is the same for Part 21, thats they reason why they have received that authority. If they make mistakes, or approve things which can not be approved according the regulations they will revoked. I can not imagine that this would be different under FAA.

JP-Avionics
EHMZ

There is no need to contact anyone within EASA. You could just apply for a minor change in this case.

However, this was looked at by an EASA 21 company who said it will be a Major change. Later, EASA agreed.

So that won’t work.

Under the FAA decision process it is a Minor, as are many other things. But even if it was a Major, it can be done without involving the FAA (at some cost).

There is no need to contact anyone within EASA

There is if you want to take advantage of the lower cost route, where you do the preparation yourself.

Ok, so your tired of your piston engine, and you decide to buy an Soloy engine. You would need an STC for that, under FAA or under EASA. If you would change from EASA to FAA or from FAA to EASA it needs to be reviewed again. No change for that.

This is a backup oil pressure gauge, not a different engine!

Administrator
Shoreham EGKA, United Kingdom

Although getting an FAA Field Approval can be ‘risky’ if you already committed either financially or emotionally to the modification prior to approval, the degree to which FAA pursues approved data varies considerably with the FAA individual and office. On my planes field approvals have been granted on the basis of a letter from a propeller manufacturer mentioning foreign approval, a sketch by the owner with no further data (adding a split pin to back up a snap ring that has been known to pop loose), a written reference to a factory fuel tank installation drawing that wasn’t included with the 337 (I believe an incorrect drawing number) and a similar installation using the same components in another certified type of aircraft with the same engine. AC 43.13 is generally mentioned as well. I believe all of the above were prepared by the aircraft owner, and likely submitted by the IA who subsequently supervised and signed off the installation.

I think it is generally considered true that as the technical competence of FAA FSDO staff has decreased over the years, more ex-military and less GA-experienced career FAA people, the flexibility for FSDO approval of 337s covering field approvals has been reduced somewhat. That aside, I think the biggest issue in Europe is that there are no FSDOs nearby and much fewer working relationships established with FAA personnel.

It’s also worth mentioning that if you happen to fly an FAA certified type that no IA, FAA inspector or similar individual has ever seen before, and will likely never see again, the specific type of electrical switches or oil pressure gauge installed doesn’t draw a lot of attention.

Last Edited by Silvaire at 27 Jan 15:56

Peter wrote:

However, this was looked at by an EASA 21 company who said it will be a Major change. Later, EASA agreed.

No way…. It is easy to publish that, but if replacing the excisting on under CS-STAN is allowed, the installation of a backup unit, which isn’t required by anything at all, is not going to be considered as major change.

So which things are major, basically when you change aircraft performance significatly or change the flight significatly (autopilot / LPV) then things become major changes.

So some examples of work I have done as minor change, which got approved

- Installation of brake light (for an instructor which wanted to know when his students where applying brakes in the air).
- Installation of stormscope systems
- Installation of different traffic systems including antennas
- Installation of a WX radar in a different pod using the POD which was already certified.
- Installation of multiple 100 Watt HF systems, including tuner and antenna on unpressurised aircraft
- Installation of very high resolution 3D camera systems (looking downward) on multiple unpressurised aircraft
- Installation of our own air data computer
- Installation of our own datalogger
- Installation of multiple maritime VHF radios including antennas
- Installation of relaying equipment including antennas
- Installation ELT system on the bottom of the fuselage including antenna

These are just a few that stand out.

JP-Avionics
EHMZ

You should set up a shop in the UK, Jesse

Administrator
Shoreham EGKA, United Kingdom

Silvaire wrote:

I think the biggest issue in Europe is that there are no FSDOs nearby and much fewer working relationships established with FAA personnel.

This .

FAA A&P/IA
LFPN

I think the biggest issue in Europe is that there are no FSDOs nearby and much fewer working relationships established with FAA personnel.

That affects the Field Approval route only (the other is the STC route but almost nobody does that in light GA for a one-off job, though e.g. an autopilot would be one example). The DER 8110 route is still available, as of course is the entire Minor Alteration system.

Jesse, are you saying that you have installed

- Installation of brake light (for an instructor which wanted to know when his students where applying brakes in the air).
- Installation of stormscope systems
- Installation of different traffic systems including antennas
- Installation of a WX radar in a different pod using the POD which was already certified.
- Installation of multiple 100 Watt HF systems, including tuner and antenna on unpressurised aircraft
- Installation of very high resolution 3D camera systems (looking downward) on multiple unpressurised aircraft
- Installation of our own air data computer
- Installation of our own datalogger
- Installation of multiple maritime VHF radios including antennas
- Installation of relaying equipment including antennas
- Installation ELT system on the bottom of the fuselage including antenna

all without any of the equipment being supported by an STC or some other data (e.g. Installation Manuals), as a Minor mod? How much did the clients pay for your design work, submitted to EASA?

Administrator
Shoreham EGKA, United Kingdom
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