Superficial Question

[Rick6a]

Okay, I'll admit it. When it comes to engine knowledge, I'm out of my depth. That is why I trusted Van to help supply me with a powerplant known to dovetail nicely with his RV-6 design. I didn't want any surprises, and none were received. The 0-320 D1A installed in "Darla" performs beautifully and I couldn't be more happy with the choice. Basically, all I had to do was install it and that was that.

Since that time however, Lycoming has introduced its experimental line of engines offered through Van's. Several thousand dollars less than certified does tend to make you take notice. So engine gurus out there......EXACTLY what are the practical concerns, differences, and ramifications of installing a presumably identical Lycoming factory produced "experimental" engine as opposed to a certified engine...is it really just a paperwork thing or is there something more I should consider before settling upon an engine choice as a would-be repeat offender?

[pierre smith]

Hi Rick,
I asked pretty much the same questions that you did. I also found out that one engine assembler could put an engine together for you and it would be X dollars if it was "Experimental". He'd certify the same engine if you so desired, for $5000 more It seems that it may well be a "CYA" deal for liability purposes.

There are so many really strong engines that you assemble at the site in a couple of days, with them even doing the break-in in their cell, that it's difficult for me to justify additional thousands when in reality, the same parts went in the engine. .02 cents.

Regards,

[Caveman]

for me it was a pro & con type deal

Pro's of a clone included: Built with certified parts, less expense, customized engine options - choice of sump arrangement, FI brand, compression ratio, ability to run mogas, (or not).

Con's included: certified parts not certified as a whole unit, probable less resale value, (especially if ever pulled from the airplane), more risk involved with propellor interaction depending on options such as compression ratio, and ignition chosen.

Basically you choose your poison... or level of acceptable risk.

[Dave Cole]

Rick, I believe the answer to your question is that the Lycoming experimental engines that Van's sells are physically identical to the certified versions.

As the online catalog states, "These engines are equipped with the same accessories as the certified engines (see certified engine description). The engines are built to the same standards as the certified Lycomings, but do not come with the certified airworthiness paperwork."

In other words, you won't know the difference when you install one in your RV.

[Rick6a]

Dave,

I read the same thing you quoted so I will put my query into another form using much of the same wording as the original quote: Because the engines are built to the same standards as the certified Lycomings, but do not come with the certified airworthiness paperwork, what should I or what do others reasonably consider before electing to make such a purchase?

[Ironflight]

Hi Rick,

I remember reading (back a couple years, when I was making engine choices) people that had trouble getting their aircraft insured because they didn't have "certified" engines. I haven't seen a thing about that the past couple of years, so maybe that issue finally went away. But it might be a consideration.

In terms of resale value, I don't know how much a truly educated buyer would care whether the engine was certified or not. By educated, I mean someone who understands the reputation of the various high quality engine builders we have today. I personally would give higher marks to an experimental engine built by one of the big names than I would to an A&P field overhaul, based simply on the fact that I know the track record of the big name builders.

Some folks worry about the fly-off time difference - 40 hours versus 25. What, they don't like to fly?

I can't think of much else to consider. AS long as you are looking at a clone that matches a certified configuration (that is, one that doesn't have excessive compression ratios or non-certified parts), I don't think you can go terribly wrong.

Paul

[Mel]

Paul brings up the point that many people worry about the 25 vs 40 hour flight test requirements. I preach and I'm sure Paul will agree that a proper flight regime cannot be completed in 25 hours anyway. If you FULLY test your RV, you will have very close to 40 hours if not more on the clock.

[osxuser]

Originally Posted by RV7Aflyer

Once that Lycoming "Certified" engine is installed in your RV, it automatically becomes an "experimental" engine.

Why? If maintained I/A/W the FAR's, I don't see why it would not be certified. Of course, as soon as the first year is up and it needs an IA to annual a certified engine. As a Private pilot or better, oil changes would be legal. I don't know what makes a certain installation automatically decertify an engine.