wrote:
Greetings, fellow aviation nuts
(SNIP) The r.a.h. FAQ notes that certified engines need to be equipped
and maintained just the
same as in a certified airplane, and says that any non-certified engine is
subject to a 40 hour flight test program vs 25 hours.

If I'm not mistaken, for the 25 hr regimen, its a certified engine and
PROPELLER combination. Some certified airframe somewhere has to have
been approved with that specific model of engine and prop together. I
want to say its partially a matter of "resonance" issues with certain
engine/prop assemblies at certain RPMs.

Beyond that, and
knowing that people do auto conversions, I'm not finding much as to what you
can and can't do. It sounds to me like you can install practically anything.
Get a big enough twisted rubber band, or enough hamsters running on exercise
wheels, and as long as it flies you're allowed to do it. Surely it can't be
that simple

It is. Thats what Experimental - Amatuer Built is all about.

- what needs to be done before an engine will be allowed to fly?
What can't you do? Any stories of people designing and building their own
engines? (not that it's an option in our case of course)

Why not? They sell kits of some "aircraft engines", and I have the block
assembled for our auto conversion that is based on Mazda rotary engine
parts. Its not rocket science. Its about being able to follow directions
if you are fortunate enough to have people who have blazed that trail
already.



One idea we were throwing around is getting an old certified engine and
overhauling it ourselves. We're both mechanically inclined, and he's done
quite a bit of work on engines, and I'm sure there are others we could
recruit on campus. It would be a great learning experience. Since neither of
us is an A&P, we couldn't sign off on it, but it should still be a good
engine. What does the FAA think about this kind of thing? Seems that by now
someone must have tried it.

It wouldn't be "certified" at that point, but from an Experimental -
Amatuer Built standpoint its a non issue. However, a PRUDENT (in my
mind) person would have the appropriate engine manuals on hand (from the
factory) as well as be familiar with the workmanship and techniques
depicted in AC 43.13 - 1B and -2A. No REQUIREMENT to do so, but again,
good techniques.


On a different note, Q317 from the FAQ asks if it's possible to insure a
homebuilt. I hadn't really thought about "if," it always just seemed like a
given to me that you would do it, as for a car. Is insurance difficult to
get, or not commonly obtained for homebuilts, or what? And what kind of
ballpark are you looking at for a single engine, 2 seater, without the
million dollar liability policy? with/without a certified engine? how about
high performance? complex? There are probably still too many variables, I
realize, but some idea would be appreciated.

Anything is available if you want to pay enough. I have not researched
this extensively and actually intend to "go bare" with regards to hull
insurance. Heresay I have seen indicates that 1st flights or Phase 1
(flight testing) is difficult to nearly impossible to insure. Other
postings I have seen indicate that some insurers may want to inspect the
build along the way for workmanship to validate that the hull will
actually be worth what they are insuring it for (as in
repairable/sellable). No personal firsthand proof, just data points that
may or may not be valid.


Dave