RV 14 with Superior XP-400 ?

[DanH]

Everybody in the engine business has suffered crank failures at one time or another, with recalls, lawsuits, and all the rest. There is little point in headbanging Superior over the recent XP-400 crank problem.

In any case, Superior is actively looking for a new crank vendor, so any future XP-400 purchase won't include the old crank. I say "future" because right now you can't buy one.

We might also note the EAB world is cavalier about ignition advance, which can add significant crankshaft mechanical stress. Let him without sin throw the first stone.

The deleted court links were interesting only from the standpoint of identifying outside parties, information an engine company generally guards as top secret. Outside vendors are a fact of life for everyone, although Lycoming and Continental are both working toward integrating more of their supply chain in house. Lycoming's automated piston production and Continental's German machining facilities are good (public) examples.

So, we have a crank forged in Europe, machined by a US contract shop, sold by Superior, and possibly flown with far too much ignition advance. IIRC, the forensic metallurgical reports indicated a below-the-surface initial point, generally undetectable in a QA inspection. At the micro level, there are probably a few such inclusions in every crank, of any vintage, from every manufacturer. To find them, all you need to do is stress the crank hard enough. The 215HP XP-400 shares journal diameters with the slightly smaller displacement Lycoming-pattern engines, so its design sin (if we were to point fingers) is stressing those journals a bit more. Nothing is perfect...and we might also note the new 215HP rating for the cold air version of the 390.

[Full Throttle]

Search for "XP-400" and the NTSB final report for N838RV will come up. You can find the info you are looking for there.

[NorrisAir]

The original question was the xp400 in an RV 14. I completed my RV14A with the XP400 engine in April 2017 and have since flown it 267 tach hours. I have flown it ROP and LOP depending on my mood and it has worked fine both ways. Engine has the cold air sump, is fuel injected, and ignition is two PMags. Prop is a three blade MT. On item I liked when hooking up the mixture control was the direct connection instead of having to use the "monkey motion" connection that vans fwf kit has for the IO390.

[Full Throttle]

Your right Norris. The discussion about the XP-400 crankshafts breaking should go back the (Traditional Aircraft Engines) category.

[Cwood2000]

Jeff, I may not be able to wait for and for the discount. I think I'm going to buy right after the holidays. Last time I spoke with Superior, they still had a 12 month lead time. That won't work for me. I'm going with a Thunderbolt.

[dmattmul]

I was set to use the XP400 and when I went to order found out that at a minimum 18 month lead-time. Will not work for me. I have no comment on the technical issues just 18 months lead time is not what I can withstand. I hope Superior gets this works out for the good of experimental builders.

[dmattmul]

I ordered the Lycoming and the rep (Jeff Schans) did a nice job of getting me what I wanted. (EFII systems) They will work with you to custom paint what you want.