Do Not Stray far in Phase I -Pt 2

I was initially hesitant to post this incident, but I decided if it was useful to anyone else it was worth it.

The engine is a new Lycoming Thunderbolt YO-233-EXP. I had Lycoming run it for two hours in the test cell.

I had been very happy with the engine. It was a smooth efficient running engine. I had not noticed any unusual readings or conditions in the first 20 hours.

The failed Connecting Rod Bolt has a beveled head on one end and threads and a nut on the lower end. The Connecting Rod Bolt failed and the nut and threaded end of the bolt disappeared ( Down in the sump?). The middle of the Connecting Rod is also missing, remaining are two stumps (~1? each) on the crank shaft end of the Connecting Rod and the piston end ( also down in the sump?).

First my good decision.
I chose to fly a race track parallel to the main runway at KMMV offset about five miles. My incident plan was, with an issue at the east end of the racetrack I would head for runway 22 , if the issue was at the west end I would head for runway 04, in the middle I would head for runway 35. In the actual event, runway 35 was about 40 degrees off the left wing at about five miles.

I discovered the Dynon Skyview has data logging.

Map


Oil Pressure


CHT & EGT


Sorry for the poor images they are photos of a printout and I do not know how to rotate them.

As Bubblehead said, that is a long/very short five minutes. In my case, engine failure to touchdown was about five minutes also. Pilot workload also peaks during that period, BIG TIME.

I would have guessed 1-2 minutes to touchdown, but the datalog shows nearly five minutes.

The datalog shows Oil Pressure dropped to near zero in about 30 sec.

The CHT Datelog shows the #3 cyl stopped moving quickly. The vibrations were a result of a three cyl engine running at 2000 rpm.

The CHT also shows that the three cyls were still running when I added throttle to insure I made the field.

I hope this adds to the collective knowledge and may be useful to someone else.

You did an outstanding job of dealing with the partial engine failure. Thanks for sharing for the benefit of us all.

Well done!

Knowing that everyone is safe, I'm curious about the financial aspect of such an event. Is there any expectation of assistance from warranty and/or insurance for the intensive labor involved the R&R the engine plus the consumables to do so?
What about the costs of having to start your test period all over again?

Glad you're safe. In a way it is probably a blessing it happened when and how it did. Just curious what kind of wallet hit this could be for something that isn't your fault.

I hate the thought of "recourse" and want to keep lawyers out of experimental aviation, but by the same token, a company like Lycoming should, and hopefully will, make you "whole" in light of their "hole" in the crankcase, and "whole" goes way beyond a fixed or replaced engine in a crate.

No reason to start the test period over. This is simply a repair as far as testing goes.

I see your point Mel, however there are sure to be modifications to fuel, air, or spark in an R&R, and if I had just gone through that and had an engine catastrophically fail halfway through, I wouldn't have the warmest of fuzzies calling a test period complete and boarding my family with a replacement engine with the exact same tenure as the one that had just failed.

At least if I were negotiating a settlement with Lycoming anyways.

In the late 80's a student of mine was a test pilot for an aircraft manufacturer and had three successive engine failures on three successively numbered factory engines.

woxofswa said:

Just curious what kind of wallet hit this could be for something that isn't your fault.

I hate the thought of "recourse" and want to keep lawyers out of experimental aviation, but by the same token, a company like Lycoming should, and hopefully will, make you "whole" in light of their "hole" in the crankcase, and "whole" goes way beyond a fixed or replaced engine in a crate.

Click to expand...

Hope you have better luck with Lycoming than I had with Superior - when I had a rocker boss failure a few years ago resulting in a similar forced landing (and similarly no damage to the airframe) it cost me north of $10k because Superior was out of business at the time, so basically no warranty. The interesting thing is that if I had run off the end of the runway or done some other damage to the airframe, my insurance would have covered everything, but with a successful forced landing there was no insurance coverage because it was not deemed an accident/incident.

Greg

woxofswa said:

I see your point Mel, however there are sure to be modifications to fuel, air, or spark in an R&R, and if I had just gone through that and had an engine catastrophically fail halfway through, I wouldn't have the warmest of fuzzies calling a test period complete and boarding my family with a replacement engine with the exact same tenure as the one that had just failed.
At least if I were negotiating a settlement with Lycoming anyways.
In the late 80's a student of mine was a test pilot for an aircraft manufacturer and had three successive engine failures on three successively numbered factory engines.

Click to expand...

I understand completely. My point is that Phase I actually has nothing to do with time. Phase I is not complete until all testing is complete.
The time limit in you operating limitations is simply a minimum, not a maximum.