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interesting, did Honda test out the planetary gear box strapped up front, or as you say someone cobbled a bunch of parts together?
Is a magneto sparked, gravity fuel fed engine with no external need except air a reliable design? Or is a liquid cooled, electrical power dependent one more suitable?
Aircooled engines less efficient , yes. Are automotive engines required by law to be more fuel stingy, yes.
I'm sure Honda automotive does not actually support fit engines in aircraft use or they would market their own.
Despite knocking Lycoming, or indirectly Continental. Both build a crank designed to support front thrust bearings, providing self ignition, when fuel is provided.
If folks want to buy a Viking I support them, but it is still a conversion of related technology
You asked, "Is a magneto sparked, gravity fuel fed engine with no external need except air a reliable design? Or is a liquid cooled, electrical power dependent one more suitable?"
According to Mark Kettering (former aerospace engineer at NASA) a modern auto engine with fuel injection and single electronic ignition is far more reliable that an engine with two magnetos. Add in the possibility of carburetor failure and it gets even worse for the legacy engines.
Just the facts ma'am.
this discussion seems to be going south now, so a(former aerospace engineer at NASA) is now an expert in internal combustion engines, claiming a single source failure mode is more reliable. I guess if the "expert" says so.
P.S. never had engine failure with conventional engine 12,000+ hours , except in turbine powered helicopter. Damn army crap (joking) failed oil line after depot maintainance.
just checked Mark is also selling car parts
Proper failure analysis can (and does) predict with near certainty the overall chances of failure of various components and groups of components. One can choose to believe these statistics, or not. Personally I tend to give great weight to scientifically derived data, and far less weight to a single person's anecdotal experience. Others approach this differently. But it was you who asked the question. I merely attempted to give you an answer based on fact.
seems as you've traveled this road before
my 1930's technology engine is powering my 1903 technology aircraft, just a few questions (inspired by your geared engine discussion ) What RPM did the Lycoming or Continental geared engines operate? what engine RPM is used in Viking cruise, how about when used in a car; what RPM at highway cruise? apparently the room maintains that this new technology is somehow safer and more reliable, I guess time will tell. When removing the previous car engine from my airframe I did consider Viking but did not want to deal with extensive fuel system rework
Your rpm questions seem to imply that because autos run at much lower continuous rpm, then pushing them to much higher continuous rpm would naturally be unadvised. This would be a natural response. However, you might be interested to know that Honda uses the same engine that Viking uses in their marine applications, where continuous rpm is right up there with aircraft applications (as well as coupling them to gear reduction).
You could well be right about them not being the same. Could have different cam, etc. I have never been able to find out. But it is the same "basic" engine.
I have about 34 hours on my VIking on a Zenith 750, another fried finished his air-cooled airplane about the same time. We both had some temperature issues with our cowls soon after first flights, I was able to add some ducting and wrapped the exhaust and now I have almost unlimited ability to use WOT on a hot day.
I had to tune for one number, the coolant temperature. My friend is weeks into his testing and still not able to leave the pattern dealing with head temperatures and balancing out his CHT across several cylinders.
This really simplified the equation. I also don't have to worry about carb heat or mixture and it starts every time without any though or effort. In hundreds of hours of flying Lycoming and Continental engines I maybe get one start in 4 on the first crank, and that usually involves a long sustained use of the starter, not the tiny blip you need on the Viking.
Certainly time will tell as to if I have any downsides to the technology, but so far I am really enjoying the advantages. Oh and with the money I saved I am enjoying that new-tech glass cockpit I could afford. :-)