When does a Lycoming become ?Experimental??

[Noah]

FAA requires a 25 hour flyoff for a "certified" engine / prop combination, 40 hours for all others. Insurance for your RV is cheaper if you use a "certified" engine and prop as well.

But what does this mean, really?

I'd like to install an Airflow Performance purge valve, and maybe a Lightspeed or some other EI on my engine. If I do this, however, it is no longer "certified", right? It no longer conforms to the type certificate data sheet, overhaul manual, drawings, etc. I certainly couldn't get away with putting one of these in a Cessna without an STC or a 337. So do you need a 40 hour flyoff if you use a lightspeed on a Lycoming engine? Or does the FAA / DARs "look the other way" with regard to "minor engine mods" like these. Is insurance more?

I'm getting ready to overhaul my Lycoming in a local shop but I don't think my A&P, who is a "by the book" type guy (as well he should be!) is willing to allow aftermarket or non-yellow-tagged stuff on there.

I had been hoping to keep things "certified" as much as possible with the engine and prop for the aforementioned reasons. But Airflow Performance wants over $1000 MORE for a yellow tagged fuel servo, because they have to throw away all the old parts, even if they're still serviceable. Don from Airflow says "From a reliability and functional stand point there is no difference in an experimental overhaul and a certified overhaul when the systems leave our shop. The choice is yours".

This has me thinking, maybe I should forego this approach of keeping everything "certified" and yellow tagged. What do you think?

Is George McQueen still on here? I always appreciated his insightful (and detailed!) responses on these kind of engine issues...

As always, thanks in advance for your comments.

[Mel]

You are correct. Anything you do to the engine that varies from the type certificate makes it experimental and it immediately goes to a 40 hour fly-off. Also remember, it must be a certificated engine/PROP combination to qualify for 25 hrs.
On the other hand, you cannot do a complete test program in 25 hours anyway. If you do, you have missed something.

[MSFT-1]

Mel:

I am interested in a list of items to flight test (in my case for an RV-10). I have flown off the full 40 hours but for the life of me I couldn't think of much to test after about 20 hours.

Here is a list of some of the things I did:

Weight and balance scenarios
Slow flight and stalls
Determined Vx and Vy and best glide
Speed tests
Engine cooling and sensor tests
Oil consumption
Electrical load tests
Fuel tank calibration
I worked all the bugs out of the avionics (mostly)

After about 20 hours I mostly flew approaches (VFR).

Did I miss anything?

thanks,

[Rivethead]

This is what I was told. If you take a certified engine and hang it on an experimental, and I suppose fly it, you can't swap it back to a certified aircraft without at least having an A&P re-certify it. So, lets say I have a perfectly good 172 with an O-360 I pull the engine off and fly it for say an hour on the RV. According to my source I can't pull that engine back off and put it back on the 172. Not without jumping some hoops.

[Noah]

OK, I can accept a 40 hour flyoff, especially since Mel says it will take that long anyway. But what about insurance? I would think that most people would say to their insurance company "I have a certified O-360", even if they put a lightspeed on it. Are the insurance companies savvy enough to know that you have an experimental engine if you took off a mag and put on a lightspeed?

[n5lp]

Originally Posted by Noah

OK, I can accept a 40 hour flyoff, especially since Mel says it will take that long anyway. But what about insurance? I would think that most people would say to their insurance company "I have a certified O-360", even if they put a lightspeed on it. Are the insurance companies savvy enough to know that you have an experimental engine if you took off a mag and put on a lightspeed?

I have a 100% experimental Aerosport O-360 on my airplane. I can't prove it, but I doubt if I pay a penny more than someone who went to the trouble to have a Lycoming O-360 and certified propeller combination. Of course the insurance companies aren't dumb. The more "experimental" your engine becomes the more likely, I think, that it will cost more.

I strongly advise being completely honest with your insurance company. If you aren't, you might as well not pay the money at all. They may not take fraud lightly and would be within their rights to deny a claim if they find there was willful misrepresentation. I think this would also be well within their moral rights.

[erich weaver]

I recently got a few quotes for insurance. Nobody asked anything about the engine - only the airplane itself. I think you will find it doesnt make any difference.

erich

[Noah]

Originally Posted by n5lp

Of course the insurance companies aren't dumb. The more "experimental" your engine becomes the more likely, I think, that it will cost more.

I strongly advise being completely honest with your insurance company. If you aren't, you might as well not pay the money at all. They may not take fraud lightly and would be within their rights to deny a claim if they find there was willful misrepresentation. I think this would also be well within their moral rights.

I agree wholeheartedly, Larry. I guess the point I'm making is twofold:
1. Does your average RV builder KNOW that they no longer have a certified engine if they take a Lyc out of a certified airplane and make a simple mod to it, installing an aftermarket part like a purge valve? I didn't, until I read Mel's post, but then again, I'm a little wet behind the ears when it comes to this stuff! I would've thought this was part of the airframe's fuel system, not the engine, but what do I know?

2. Does the insurance company send a detailed questionnaire with their application, effectively wanting to see your master equipment list? How detailed are they in asking what you have for an engine, and what parts you used, and whether they were yellow tagged, and whether an A&P signed off the engine? Do they want to see the logbooks? Is it misrepresentation if they don't ask, and you don't tell? (Doesn't the military have a policy like this?)

How would the insurance company know to charge you more for your Lycoming which is "more experimental" than somebody elses?

[n5lp]

Originally Posted by Noah

...Is it misrepresentation if they don't ask, and you don't tell?...

I think you will be fine if you just answer the questions. I can't remember how detailed my initial chat with the agent was. I'm not sure if he asked if it had a carburetor or fuel injection. I do remember him asking what the engine was. He didn't even pause, he knew what it was. Something less common, maybe there would be more questions.

By the way, I just filled out my renewal form today, if you can call that filling something out. I really like the way SkySmith lets you fill out an online form now, that has the old data right there. Just change what has changed. Mucho convenient.

It still says Aerosport O-360 in the engine box, there is no box for the propeller.

[Noah]

I had been planning to work with my A&P to do this overhaul in an arrangement where he oversees the work and provides assistance as necessary, and then signs it off when done. I may have to rethink this based on this discussion. So the takeaways from this, as I see them, are:

1. If I want to put a non-LASAR EI or a purge valve on my engine, it will not be certified anymore.

2. Such a non-certified engine will require a 40 hour flyoff, not 25.

3. A good flight test period will take this long anyway to wring out the bugs.

4. There is unlikley to be any increase in insurance as a result of these changes to the engine, and

5. There is probably NO POINT in having an A&P sign off the engine, if that means doing the overhaul, and then making the several planned changes I want to make afterwards, because it will cost a lot more time and money. I would be better off just going "experimental" on the engine from the get-go.

Whaddya think, do you agree with this logic??