Aerovee engine concern

[kmacht]

Since posting my concern, I've spoken to a few previous Aerovee owners who had crankshaft/hub failures. According to them, they did not have prop strikes and their engines were assembled correctly.

I might try and contact Sonex to see if they have any history data.

Joe,

Can you site any NTSB reports or specific planes to back this up? I have been following the aerovee crankshaft reports for years now and still have yet to come across a failure that didn't involve either a prop strick or an assembly/disassembly issue. If there are reports I would really like to know about them since I too am planning on flying behind an aerovee. About the closest one I have seen is where someone bought a Sonex second hand and wasn't aware of a previous prop strike or various other problems with that aircraft.

Keith
#554

[Dan]

Why would anyone in their right mind fly airplane that has had a prop strike? If you bought an aircraft that had one before you bought it and the owner didn't disclose that then OK. But if you fly a plane with a known prop strike then you deserve your fate.

[radfordc]

Who said my mind was "right"?

[Dan]

LOL! That's what I get for assuming.

[Dan]

Robbie I was speaking of liability only for the prop hub/crank assembly. I know it's a kit plane but don't you think there should be some sort of guarantee for something that you or I paid over $200 for the factory to assemble.

[Andy Walker]

Why would anyone in their right mind fly airplane that has had a prop strike? If you bought an aircraft that had one before you bought it and the owner didn't disclose that then OK. But if you fly a plane with a known prop strike then you deserve your fate.

As long as the engine has been torn down and inspected properly, a prop strike should not be an issue. Most prop strikes do no real damage, but the potential is definitely there.

That said, if I had a prop strike in an Aerovee, I'd probably replace the crank and hub, or at the very least replace the hub. It's one of the weaker areas of that design, and no sense tempting fate. :mrgreen:

[Dan]

I'm with you on this Andy. This thread got me wondering about the prop clearance on a trigear Sonex using the recommended prop for the Aerovee. This thinking prompted by my sometimes less than graceful landings.

[Mike53]

[quote="joepowel70"]I'm concerned about using the Aerovee engine on my airplane. I recently heard of the accident involving an Aerovee and a Sonex crashing in WI because of the propeller.

Are there alternative engines? Is this a design flaw, builder error, part defect? Have there been previous failures? Opinions?
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
After irritating a few people on the other forums about this issue ,Sonex came in with this response.I have highlighted in red the answer I have been looking for from Sonex.Am I satisfied? Yes,I have not found one instance of a crank/hub/prop failure as the direct result of the attachment method used by Sonex.In one accident report Sonex was admonished for not giving instruction as to the proper method of removing and then reattaching the hub to the crank.Sonex claims this hsas been rectified.I for one will have Sonex attach the hub for me if I decide to go with the Aerovee though I think they are charging to much,considering the anguish this issue has elicited .jmo

Hello again AeroVee and Sonextalk Groups-

Sonex Aircraft will continue to study the recent crank shaft break, which
has been quoted on these lists going on 2 weeks now...again providing the
incorrect perception that this is a widespread problem.

We hope that our competitors who have long claimed to have a superior
product will reveal the problems and failures that they have had with their
crankshaft assembly. It should be further noted that the AeroVee continues
to dominate the VW Conversion Market, so there are simply many, many more in
the field...it's a much larger sampling to take data from.

I personally believe that those that have a preference for a "Force-One"
type prop hub do not understand the shrink fit design of the AeroVee and
probably have not even seen it. I would encourage those who have concerns to
have a look at the components that comprise the installation (and the entire
AeroVee Conversion for that matter) which will result in an understanding of
the strength, simplicity, and elegance in form and function. We
always have a forum and Booth at AirVenture and have an entire presentation
on Engine Development as part of the Sonex Workshop.

As was already pointed out on these lists, Aircraft engines of all types,
including type certified engines have had mechanical failures of all types.
None of us that design, build, test, and sell engines and engine conversions
want to see a single failure, but they happen. Our job is to learn what
caused them and, when appropriate, issue Service Notices and/or Product
Changes if we feel they are warranted.

It is also the owner/operator's responsibility to accurately and truthfully
report all circumstances surrounding an incident so a proper and well
informed investigation can be made, and facts, not speculation, reported to
the fleet owner's. Too often pride or the desire to blame others prevents
this from happening.

As stated before on these lists, we continue to fly 8 of our AeroVee Engines
in factory Sonex aircraft and have been flying successfully behind our same
basic shrink-fit hub design for 11 years. 5 of the factory installations are
the AeroVee 2180/2.0 design and 3 of the factory installations are the
newest AeroVee 2.1. Our competitors in the vw conversion business do not
maintain a fleet of test engines and do not regularly fly behind their own
engines.

The most common concern we heard from customers was with their ability to
successfully achieve the shink-fit installation, which we answered by
offering an "Assembled Crank Shaft" on the AeroVee 2.1:
http://www.aeroconversions.com/products/aerovee/

We appreciate the efforts of those who continue to root out the
misinformation that is all too readily spread amongst egroups, builder
Forums, and fly-ins and builder gatherings.. Sonex agrees that sticking to
facts is always the best course of action when discussing any company's
products.

There are 2 versions of the AeroVee Crankshaft Assembly:
The AeroVee 2180/2.0 version was sold from 2001 through 2008
The AeroVee 2.1 version with a custom crankshaft and hub has been
shipping since 2008.

To date, there has never been a failure of either a factory-assembled
AeroVee Crankshaft (2180 , 2.0 or 2.1) or of any 2.1 AeroVee Crankshaft
Assembly including all customer-assembled units.

As always, please feel free to contact Betty, John, Jeremy, Kerry, Mark,
Heather , Jason, or Stephanie at the numbers or e-mail below
with any questions or Comments.

Regards,
-Sonex Aircraft, LLC
--
http://www.sonexaircraft.com
Tel (Info/Orders): 920.231.8297
Tel (Tech Line): 920.230.8324
Fax: 920.426.8333
E-mail: jeremy@...

[Sonex1517]

as much as I love online forums, this is the part I am not fond of. Of course, the same occurs at the airport in person at times....when I spent my weekends jumping out of airplanes instead of flying them, the same thing happened at the bonfire each evening and the expert usually had 10 jumps....

I always try to listen and then look for facts - in this case the facts were never found. Thanks for that post Mike. Most informative.