Required certification level on aircraft reconfiguration. 3

[heinessen]

Hello.

I am a cabin engineer working at airline.
I am writing this post to make sure what certification is required for aircraft reconfiguration.
Our company usually get a STC for cabin reconfiguration in previous modification programs.
But I heard that some airlines or aircraft leasing companies get only FAA 8110-3 for cabin reconfiguration.
I am wondering why this difference is made.
To the best of my knowledge, STC is required if there are major changes on aircraft during reconfiguration but FAA 8110-3 is only required if there is only minor changes.
I would like to know if my understanding is correct.
In addion, I would like to know what the major diffrence between STC and 8110-3.
I think STC have some more steps than 8110-3 but please let me know if anyone could make comparision between STC and 8110-3.

Thank you.

 

[der8110]

Greetings,

Cabin outfitting and subsequent modifications are not required to be STC’d (or part of the TC). They may be done by engineering approval - DER 8110-3 or ACO approval.

The history is that a decade or so ago, FAA Aircraft Certification and Flight Standards got together to decide what should be STC’d, what could be done by engineering approval, and what could be Field Approved. For a while, the document did say “all cabins must be STC’d” but the FAA later came back and decided that was not their intent, and revised the document to how it reads today. It is called the “Major Repair and Alteration Data Approval Online Job Aid” and can be found at:

fsims.faa.gov/wdocs/other/Major_Repair_Alteration_Job-Aid.pdf

Look for items I.1 and I.2 under Transport Category airplanes.

Lessors may have STC’s as a requirement of a lease agreement, that is contractual.

An 8110-3 is not appropriate for Minor Alterations, see Order 8110.37E section 4-12.b.

As far as differences between STC’s and DER 8110-3’s, here are some compare & contrast points:
- No application for an 8110-3. If there are Field approved aspects, some FSDO’s do require an application and a few even make it harder than an STC.
- No Certification Plan required for an 8110-3, though proper project planning should still be there.
- No Conformity Inspection Plan or Conformity Inspections required for an 8110-3, though components may need PMA or TSO approval.
- A similarity is that data (both descriptive design data and compliance data) is needed. DER’s can only approve data, which leads into....
- Another similarity is that a Compliance Inspection of the cabin may be necessary. This is not to be confused with Conformity Inspections. When is a Compliance Inspection necessary? That’s a topic for another post. Some examples are repetitive rows and installations mirrored left/right, assuming the data is good enough and the original configuration data complied.
- STC’s may be advantageous if there is testing involved.
- Aircraft support documents can end up being close to the same, AFMS, ICA, etc.

Hopefully this gets you further along. There’s a wide range of experiences out there and others will be sure to offer theirs.

 

[Sparweb]

Der8110
Thanks for that link


STF

 

[dgapilot]

To add to this a little, use AC 43-210A as a guide. As a Function Code 51 DAR, I'm required to use the AC for all Field Approvals. As a DER with repair and alteration authority limited to what can be Field Approved, I find the AC very helpful in organizing what is required for a given alteration.