Front fell off....

Crankshaft failure - broke behind the flange.
VW engine, but it took 14 minutes for that little tidbit to come up in the video...

edit: doesn't mention if it was from a "VW converter" or just a junk yard engine stuck in as-is.
 
Oh crap. Good video. VW engine. The second half where he talks about the "junk" avionics he used to make it IFR certified is almost as impressive as the job he did getting it down.
 
Lucky the CG stayed centered enough to land the airplane. I believe for some planes the if the prop departs the CG moves too far aft to keep the nose down and control the airplane.
 
Bill said:
Lucky the CG stayed centered enough to land the airplane. I believe for some planes the if the prop departs the CG moves too far aft to keep the nose down and control the airplane.
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I had the same thought. My prop weighs 75 lbs and is a LONG way from the CG. I haven't run the numbers but if I was anywhere close to the aft limit I'm sure I'd suddenly be way outside the envelope. It looked like he had some kind of composite prop, and being fixed pitch it was surely pretty light.
 
Bill said:
Lucky the CG stayed centered enough to land the airplane. I believe for some planes the if the prop departs the CG moves too far aft to keep the nose down and control the airplane.
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You'd need a seriously heavy prop for that. Losing the whole engine, now, would be problematic.

VWs usually spin small wooden props that don't weight much at all. Small, because they rev at 3300 RPM sometimes.
 
AV8R_87 said:
Did the propeller land outside the environment?
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Not sure. But they're definitely going to tow the plane out of the environment.

To be clear: That's not supposed to happen.
 
The comments here are almost as bad as media reports (uninformed assumptions). The guy who was in the accident had just bought the plane recently and flew it across the country home. He did not cobble together the instrument panel as most of it was existing from the previous builder. The motor was a Aerovee 2.0, not some cobbled together junkyard engine. The prop on the aerovee iis 54” and either wood, wood core with composite covering, or pure composite. It weighs just a few pounds and would have very very little to no effect on CG and the ability to control the airplane. The cause of the crank breaking has not yet been determined as he hasn’t torn the engine down. The motor used the earlier 2.0 aerovee crank that had a larger attachment bolt and deeper woodruf key as the weak points compared to the 2.1 version but failures to date have been due to prop strikes and/or misassembly of the shrink fit hub. Being a second owner he doesn’t know if either of those are potential causes as he didn’t build the motor and hasn’t disassembled it to get the crank out and examine it yet. There was also a service bulletin on the crank bearing right in the area it broke to remove a restrictive plug in the oil gallery feeding the bearing and he hasn’t confirmed if the previous builder completed that work or not.

How about we keep comments to only the facts and not rampant speculation on something you know nothing about.
 
kmacht said:
The comments here are almost as bad as media reports (uninformed assumptions). The guy who was in the accident had just bought the plane and flew it across the country home. He did not cobble together the instrument panel as he didn’t build it. The motor was a Aerovee 2.0, not some cobbled together junkyard engine. The prop on the aerovee iis 54” and either wood, wood core with composite covering, or pure composite. It weighs just a few pounds and would have very very little to no effect on CG and the ability to control the airplane. The cause of the crank breaking has not yet been determined as he hasn’t torn the engine down. The motor used the earlier 2.0 aerovee crank that had a larger attachment bolt and deeper woodruf key as the weak points compared to the 2.1 version but failures to date have been due to prop strikes and/or misassembly of the shrink fit hub. Being a second owner he doesn’t know if either of those are potential causes as he didn’t build the motor and hasn’t disassembled it to get the crank out and examine it yet. There was also a service bulletin on the crank bearing right in the area it broke to remove a restrictive plug in the oil gallery feeding the bearing and he hasn’t confirmed if the previous builder completed that work or not.

How about we keep comments to only the facts and not rampant speculation on something you know nothing about.
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There must be a bunch of hidden posts you’re referring too, or you read a different thread than I did. :dunno:
 
Salty said:
There must be a bunch of hidden posts you’re referring too, or you read a different thread than I did. :dunno:
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Think he's referring to the posts on YT.
 
kmacht said:
The motor was a Aerovee 2.0, not some cobbled together junkyard engine. The prop on the aerovee iis 54” and either wood, wood core with composite covering, or pure composite. It weighs just a few pounds and would have very very little to no effect on CG and the ability to control the airplane. The cause of the crank breaking has not yet been determined as he hasn’t torn the engine down. The motor used the earlier 2.0 aerovee crank that had a larger attachment bolt and deeper woodruf key as the weak points compared to the 2.1 version but failures to date have been due to prop strikes and/or misassembly of the shrink fit hub. Being a second owner he doesn’t know if either of those are potential causes as he didn’t build the motor and hasn’t disassembled it to get the crank out and examine it yet. There was also a service bulletin on the crank bearing right in the area it broke to remove a restrictive plug in the oil gallery feeding the bearing and he hasn’t confirmed if the previous builder completed that work or not.
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Well, that's a whole lotta info not in the video...
 
The last line he speaks in the video was my greatest concern for him. When I learned that he was planning to use his Sonex for night/IFR I offered a gentle warning:

SonexBuilders.net View topic - XC vlog from Illinois to Maine!

www.sonexbuilders.net www.sonexbuilders.net

I'll reserve comments on the VW conversion on his plane except to say I had one on a previous nose roller Sonex. It's good to be flying Corvair power now.
 
Daleandee said:
The last line he speaks in the video was my greatest concern for him. When I learned that he was planning to use his Sonex for night/IFR I offered a gentle warning:

SonexBuilders.net View topic - XC vlog from Illinois to Maine!

www.sonexbuilders.net www.sonexbuilders.net

I'll reserve comments on the VW conversion on his plane except to say I had one on a previous nose roller Sonex. It's good to be flying Corvair power now.
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If its limits are respected the aerovee can be a capable and reliable motor but it takes more than just following the simplistic assembly manual to get it that way. There are numerous things the manual misses or just assumes is right because they mistakenly trust the quality control and tolerances on the new aftermarket parts they sell as a kit to all be the same. The aerocarb they sell with it has no place on anything in the air and the turbo option is just a disaster waiting to happen though.

If I were to start over on another sonex build I agree with you that the Corvair is the perfect combination of price vs performance in the sonex airframe. I actually bought and disassembled two Corvair motors with the intention of converting my sonex over but the cost of the motor coupled with the need to buy a new motor mount, titanium gear legs, new cowl, and repainting the cowel to match the existing 3 color paint job just started adding up to too much money. Instead I converted the aerovee to a GP force 1 crank and hub, designed a 35 amp alternator for it that actually charges at idle and am putting in a SDS fuel injection system. It will never compete with the extra 20-40 hp a Corvair provides but will take all the things I worried about as an engineer out of the motor.
 
kmacht said:
If its limits are respected the aerovee can be a capable and reliable motor but it takes more than just following the simplistic assembly manual to get it that way. There are numerous things the manual misses or just assumes is right because they mistakenly trust the quality control and tolerances on the new aftermarket parts they sell as a kit to all be the same. The aerocarb they sell with it has no place on anything in the air and the turbo option is just a disaster waiting to happen though.

If I were to start over on another sonex build I agree with you that the Corvair is the perfect combination of price vs performance in the sonex airframe. I actually bought and disassembled two Corvair motors with the intention of converting my sonex over but the cost of the motor coupled with the need to buy a new motor mount, titanium gear legs, new cowl, and repainting the cowel to match the existing 3 color paint job just started adding up to too much money. Instead I converted the aerovee to a GP force 1 crank and hub, designed a 35 amp alternator for it that actually charges at idle and am putting in a SDS fuel injection system. It will never compete with the extra 20-40 hp a Corvair provides but will take all the things I worried about as an engineer out of the motor.
Click to expand...

Lots of folks run VW conversions on various aircraft with good success. But VWs have limitations (mostly heat related) and sadly many homebuilders do not have the mechanical aptitude to assemble a reliable auto conversion aircraft engine from parts that are sent from various suppliers. I'm a pretty fair mechanic but I had my Corvair built by Dan Weseman (Sport Performance Aviation) and that was an excellent choice and worth the cost.

I have wondered why Sonex never considered adding a 4th bearing to their set-up. Their later VW conversions seem to be some better with the new crank but I still contend that 80 HP isn't enough for the Sonex two seat airframe. I agree about the aerocarb and the turbo.

I've followed your updates on the other site. I applaud your approach. I believe the fuel injection will give much better fuel distribution providing some additional power and better engine cooling. The plane that Peter van Schalkwyk brought to ASA at Crossville was very well done and impressive. Your choice of a 4th bearing is wise.

ETA: I would never fly a VW or Corvair in night/IFR conditions in a Sonex.
 
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