another Autoflight gearbox failure - this time after 34 hrs

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Well-Known Member
Jun 29, 2010
Coastal North Carolina/USA
The folks selling Jeff's Legend offer a Mopar 8.3L V10 with AutoFlight PSRU as a power option. I think I asked in this forum once if anyone has seen an aircraft so powered with no response.
To my ears, this engine sounds more like a Merlin than any LS V8 or the Falconer. I'm not an engine guy so I don't know if the V10 is a good aircraft engine candidate.

Jason Crossley

New Member
Mar 2, 2020
The Viper engine is an odd fire (90-54) degree engine. To me they sound like a bread truck when they go buy especially the earlier ones with side pipes. I'm surprised no one has done a split pin crank to address that. Most likely the addressable market is not big enough to sustain the engineering cost, but is certainly do-able. You would also need the appropriately ground camshaft as well. They are at their core an LA series (small block mopar) with an extra pair of cylinders. Decent aftermarket support as well. I know of a few that do standing mile, that are over 1500HP. Totally different use case than the workload seen in an aircraft, but they can make some steam.


Apr 22, 2020
Brisbane, Australia
Hi - I’ve read a couple of different stories. The main issues seem to stem from the engine. From what I have read on, another engine builder assessed the Falconer as inherently flawed. You can see a technical breakdown of the issues relating to harmonics. This would apply to the LSV12 as well due to the bank angle.
The gearbox suffers as a result of this.
I really like the idea of turbine performance and reliability as well as weight savings. I’m not sure the V12 option is great given all the issues with that power and transmission.
It’s a while before I have to worry to hard about that decision though.