Operational Limitations (EAB)

In the July issue of Sport Aviation, page 100, sidebar "Builder Hints to add value when it is time to sell".

The author mentions the performance, weight balance and associated limitations are not referenced by the operational limitations/rules from the FAA.
I have read multiple times that MTOW is fixed by the builder and cannot be changed. In fact, I have read not even the original builder can change the MTOW.
Now, because of the article, I have gone and read multiple FAA issued EAB operational rules attached to the airworthiness certificate, the only time MTOW or other performance criteria is referenced by the FAA is for LSA.
In other sections of the FAR, any major modification, such as changing engines, or MTOW implies you need to go through Phase 1&2 testing again, but that is it.

What am I missing? Or can anyone buy a previously built EAB, make modifications including changing the MTOW, go to a DAR and repeat Phase 1&2 and be done? (convincing the DAR about safety might be something else...)

Tim

You don't even need a DAR. You just notify the FAA that you want to put the aircraft back into phase 1. Typically they'll say 5 hours, and when you've flown the 5 hours after making whatever change you want, you simply make a note in the logbook and you're done. This assumes you have the newer format operating limitations, that say a major change requires new phase 1 testing. Older op limitations say that any major change invalidates the airworthiness certificate; in that case you need to apply for new op limitations first.

Changing the MTOW would be considered a major change. But note: if the MTOW was ever recorded at over 1320 lbs., it will never be eligible for operation by a sport pilot, even if you lower the MTOW to 1320 or less.

Quote:

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Originally Posted by Dana

You don't even need a DAR. You just notify the FAA that you want to put the aircraft back into phase 1. Typically they'll say 5 hours, and when you've flown the 5 hours after making whatever change you want, you simply make a note in the logbook and you're done. This assumes you have the newer format operating limitations, that say a major change requires new phase 1 testing. Older op limitations say that any major change invalidates the airworthiness certificate; in that case you need to apply for new op limitations first.

Changing the MTOW would be considered a major change. But note: if the MTOW was ever recorded at over 1320 lbs., it will never be eligible for operation by a sport pilot, even if you lower the MTOW to 1320 or less.

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ok, thanks. Interesting how the belief that a lot cannot be changed has stuck over time.

Tim

Tim,

Changing the max gross weight of a homebuilt aircraft would be handled just like any other "major change". However, the process for incorporating a major change has taken several forms over the course of time. The exact process for incorporating a major change would depend on when the aircraft was originally certificated (or when it's most recent airworthiness certificate/operating limitations were issued). If the aircraft was certificated (or had a recurrent certification) since about 2001, then Dana's post above would be accurate. Aircraft certificated before 2001 may require specific written correspondence with the cognizant FSDO, and aircraft certificated before the late 80s may require a complete recurrent certification.

So it would be important to read and follow the specific guidance found in your particular aircraft's operating limitations when incorporating any major change (which may include changing the maximum gross weight).

Quote:

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Originally Posted by WacoJoe

Tim,

Changing the max gross weight of a homebuilt aircraft would be handled just like any other "major change". However, the process for incorporating a major change has taken several forms over the course of time. The exact process for incorporating a major change would depend on when the aircraft was originally certificated (or when it's most recent airworthiness certificate/operating limitations were issued). If the aircraft was certificated (or had a recurrent certification) since about 2001, then Dana's post above would be accurate. Aircraft certificated before 2001 may require specific written correspondence with the cognizant FSDO, and aircraft certificated before the late 80s may require a complete recurrent certification.

So it would be important to read and follow the specific guidance found in your particular aircraft's operating limitations when incorporating any major change (which may include changing the maximum gross weight).

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Joe,

Thanks for the additional details. I am considering a few planes, and will keep this in mind. Especially since some FSDO may have been slow to adopt the new changes in 2001. So I will need to read the limitations in detail.

Tim

Updating the op limitations is no big deal. When I bought my Fisher, it had the old format limitations (any major change invalidates the airworthiness certificate, no flight over congested areas, etc., and a test area 3000 miles from where I live). It was relatively simple to update them; I applied for a new airworthiness certificate with new limitations. No reinspection of the plane; the guy at the FSDO glanced at the aircraft logbooks and put the paperwork through. Took a couple of months because he wasn't familiar with E-AB but eventually got it right. The biggest hassle was taking time off from work to visit the FSDO, but afterwards he came to my home field to deliver the new paperwork (I suspect he just wanted a day out of the office).

Quote:

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Originally Posted by Dana

Updating the op limitations is no big deal. When I bought my Fisher, it had the old format limitations (any major change invalidates the airworthiness certificate, no flight over congested areas, etc., and a test area 3000 miles from where I live). It was relatively simple to update them; I applied for a new airworthiness certificate with new limitations. No reinspection of the plane; the guy at the FSDO glanced at the aircraft logbooks and put the paperwork through. Took a couple of months because he wasn't familiar with E-AB but eventually got it right. The biggest hassle was taking time off from work to visit the FSDO, but afterwards he came to my home field to deliver the new paperwork (I suspect he just wanted a day out of the office).

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Cool.

Tim

It's one thing to pencil whip in a new gross weight, but quite another to insure that the structure, including the landing gear, can handle the increased weight, and that the performance and handling won't be adversely affected. It's a homebuilt, and you can do what you want, but the laws of physics don't care what you want...

Quote:

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Originally Posted by edwisch

It's one thing to pencil whip in a new gross weight, but quite another to insure that the structure, including the landing gear, can handle the increased weight, and that the performance and handling won't be adversely affected. It's a homebuilt, and you can do what you want, but the laws of physics don't care what you want...

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For the two kits I am considering, I am going to work with the factory to do it. In one case, the kit factory already has it on the newer version of the plane. So it would be a retrofit. In the other case, it would be custom work with the factory. (I did not check with the kit companies until after I checked on the legal aspects, I know they are busy and I want to minimize bugging them)

Tim