Crankshaft failure in flight, lost propeller, no injuries

[Ethanm]

The saga continues…

After spending 4 days stuck in Ohio facing ignition and vapor lock problems (both resolved thanks to the help of some A and Ps and these forums), I departed solo on my way back home to Maine. In the final 20 mile stretch flying from KPOV to KOLE I started experiencing some minor vibrations. I tried adjusting mixture and power settings, and running on either ignition to no avail. Within 2 minutes the vibrations had increased to the point that the entire instrument panel was unreadable. At this point I switched to 121.5 and my propeller, spinner and, flange completely departed the aircraft. The engine spooled up after this and ran fine. I declared an emergency and glided to a road underneath me. Luckily landed safely with no damage to the airframe or anything on the ground. Crankshaft cracked right at the front main seal. Prop bolts had been retorqued ~20 flight hours before. The engine had the older model of crankshaft, was not an aerovee 2.1. Unsure if this potentially is related to the crankshaft failure. Very glad to have had a long straight road right underneath me, and that this resulted in the safest possible outcome. Bummed the plane will be down for the foreseeable future :(

Images after landing:
https://postimg.cc/gallery/nBwXgpj

Some news articles:

https://www.oleantimesherald.com/news/f ... e9e0d.html

https://wellsvillesun.com/blog/2023/11/ ... us-county/

https://www.nyspnews.com/emergency-land ... te-417.htm

[BobDz]

I am so glad that you are safe!

[tps8903]

Glad you landed safe. I could have swore that was a low time engine despite being older. Strange to me the crank broke. Was there a prop strike or something in the history?

[Bryan Cotton]

Wow! And great job!

[kmacht]

Great job in walking away from that one. There were a few crank failures on aerovees years ago. I believe that they all had either a prop strike or someone improperly assembñed or disassembled the shrink fit hub to the crank. As you are finding out, the groove in the crank right behind the back of the hub is a weak spot. If you ever locate the prop and hub you will probabñy find the crack initiated around the keyway and progressed back to that groove. If you decide to stick with a vw take a look at the force 1 prop hub and crank. You may be able to salvage the case when it's machined for the large bearing that hub uses. Great Plains sells the crank and hub and I had hummell do the case machining for me on motor.

[DCASonex]

Glad you are okay.

I have a Sonex, but with a A CAMit 3300 not an Aerovee, in a hangar at KOLE, (Cattaraugus Co / Olean Airport) and a decent workshop in there. My hangar is a new one but non-insulated steel so not the best for working in winter, but the main hangar there has space and is heated. Also have a flat bed trailer outfitted to haul a tail dragger Sonex. and a well equipped home shop a few miles from there. Can TEXT (not voice) me at seven one six- 498-one five seven zero if I can be of help.

David A.

[bvolcko38]

Very well done!!!!!!

[Tony4aro]

Glad you are safe... the rest can be fixed

[builderflyer]

Ethan.......what a once in a lifetime trip you've had and at such a young age. Congratulations on doing what was needed to get the plane on the ground safely. With all that's happened on this trip, I think you've probably learned firsthand why flying some of these airplanes at night or in IFR conditions is not such a good idea. Again, great job. I wish you good success going forward.

Art,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,Jabiru 3300 #261

[Bryan Cotton]

I have not heard of crankshaft failures recently. I remember there was at least one discussed on the forum years ago. Seems the new cranks or hubs are better. I sprung for the assembled crank rather than pressing on my own hub, though I'm sure I could do it.