Modification of purchased experimental gyro

rwdreams

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I'm under the impression that if I purchase an experimental gyro if I make a significant alteration I might have to go back to phase 1. But I could repair. So if I change the prerotator or replaced the engine I could still be legal but I might have to go back to phase 1. Even if I'm not the original builder. Is that correct. ?
 
I'm under the impression that if I purchase an experimental gyro if I make a significant alteration I might have to go back to phase 1. But I could repair. So if I change the prerotator or replaced the engine I could still be legal but I might have to go back to phase 1. Even if I'm not the original builder. Is that correct. ?
Mark Givans built The Predator.

When I changed from a Lycoming O-290 to a Lycoming IO-320, changed to a different propeller and changed rotor blades I filed major change paperwork and visited the Flight Standards district Office (FSDO). They defined the new phase one.

Then two gentlemen from the FSDO came out and after inspecting her with the major changes pronounced her airworthy.

I was to fly phase one for 25 hours inside a circle around Santa Maria.

I found 25 hours was not enough to do phase one.

Things may have changed and each FSDO (they may not be still called that anymore) is unique and may have different procedures.

In my opinion the best thing to do is to call your local FSDO, tell them what you would like to do and let them decide if a new phase one is required and the procedure for that.

The Van Nuys FSDO likes to know when an experimental aircraft comes into their territory.
 

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First off a prerotor is not a major item. Just need to make a note of it in the aircraft log book.

For the engine check the Operating Limitations for that gyro. It should state in there what is required after a major change. On my gyro when I changed to a different engine my Operating Limitations stated 5 hours in the test area. And the proper endorsements in the log books.

Now it's up to the DAR when he issues these limitations how much test area time he is going to add. So your Operating limitations may be different.

Each FSDO operates a little different from each other. The manager of the FSDO next to me refused to issue any LODAs for experimental Gyros. yet with my FSDO it was not a problem. I'm going back a few years here.
 
Here’s a question, after removing and reinstalling Rotors for transport or cleaning, should a log book entry be made listing the R&R and rebalancing/ stringing ? If you change the rotor system brand, do you contact the FSDO for new operation restrictions and make a log book entry ?
 
When I recently did my AWC inspection, rotor make/model info was not included. I would say no but perhaps make a logbook entry?
 
Don't the FARs require sign-off by an A&P for condition inspections and major changes to an experimental not owned by the original builder with the Repairman's certificate?
 
Things may have changed and each FSDO (they may not be still called that anymore)
The FAA website still uses the term FSDO for regional offices. Back when I started flying, they used to have GADOs (general aviation district offices) but I think those are long gone.
 
For the engine, check the Operating Limitations for that gyro. It should state in there what is required after a major change. On my gyro, when I changed to a different engine, my Operating Limitations stated 5 hours in the test area. And the proper endorsements in the log books.

Now it's up to the DAR, when he issues these limitations, how much test area time he is going to add. So your Operating limitations may be different.

Each FSDO operates a little different from each other. The manager of the FSDO next to me refused to issue any LODAs for experimental Gyros. Yet with my FSDO it was not a problem. I'm going back a few years here.

This is what my OLs say on the subject:
After incorporating a major change as described in § 21.93, the aircraft owner is required to re-establish compliance with § 91.319(b) and notify the geographically responsible FSDO of the Iocation of the proposed test area. The aircraft owner must obtain concurrence from the FSDO as to the suitability of the proposed test area. lf the major change includes installing a different type of engine (reciprocating to turbine) or a change of a fixed-pitch from or to a controllable propeller, the aircraft owner must fill out a revised FAA Form 8130-6 to update the aircraft's file in the FAA Aircraft Registration Branch. All operations must be conducted under day visual flight rules (VFR) conditions in a sparsely populated area in compliance with § 91.305. The aircraft must remain in flight test for a minimum of 5 hours. The FSDO may require additional time (more than 5 hours) depending on the extent of the modification. Persons nonessential to the flight must not be carried. The aircraft owner must make a detailed aircraft logbook and maintenance records entry describing the change before the test flight. Following satisfactory completion of the required number of flight hours in the flight test area, the pilot must certify in the records that the aircraft has been shown to comply with § 91.319(b). Compliance with § 91.319(b) must be recorded in the aircraft records.

Interesting that it only considers a change of type of engine, or prop, a major change for those items.
 
Mark Givans built The Predator.

When I changed from a Lycoming O-290 to a Lycoming IO-320, changed to a different propeller and changed rotor blades I filed major change paperwork and visited the Flight Standards district Office (FSDO). They defined the new phase one.

Then two gentlemen from the FSDO came out and after inspecting her with the major changes pronounced her airworthy.

I was to fly phase one for 25 hours inside a circle around Santa Maria.

I found 25 hours was not enough to do phase one.

Things may have changed and each FSDO (they may not be still called that anymore) is unique and may have different procedures.

In my opinion the best thing to do is to call your local FSDO, tell them what you would like to do and let them decide if a new phase one is required and the procedure for that.

The Van Nuys FSDO likes to know when an experimental aircraft comes into their territory.
To add what Vance had said, I suggest you have someone knowledgeable about experimental aircraft and does not possess an adversarial attitude towards the FAA (a good working relationship) such as an EAA Technical Counselor to join you with your meeting at the FSDO. I met Vance at the Van Nuys FSDO and together we met with the FAA reps. I've known and have worked with many representatives within the Van Nuys FSDO over the years. The meeting was very cordial, productive, and positive as it always should be so.

Wayne
 
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