I truly did not know automotive conversions were an insurance problem. Sorry for you, guys.
I think people tend to be a little bit personal on that engine debate. Hey, it's experimental aviation! Do as you please, and let the others do as they please! Just make your own opinion, and make your aircraft unique! Let me give you my rationale. "Certified" does not mean the best, or the most reliable, or the most economical, solution was applied. It simply means that no obvious hazard was found at the time of certification. Yes, aircraft engines have specific requirements. Yes, standard automotive engines do not meet all of these requirements, especially the redundancy principle (no single failure must lead to catastrophic failure). Does it mean that the 1930s technology they are based on is better than current automotive technology? Nope, it means there is no market today to justify the cost of designing and certifying something better. Does it mean that automotive engines can't be safely converted? Nope, simply that it takes some serious engineering to do it. I personally know the consultant who wrote the certification application of the Renault turbo-diesel engine (aimed at the professional aviation market, so still not cheap enough for us). His biggest problem was not engine failure rate, but... to prove that the engine could be cut at will! When I bought ZS-WEC, it was VW powered. Same technology basically as the Lycos and Cont's, but with a huge improvement: the very unreliable, tricky, finnicky and expensive ignition system called "magnetos" had been replaced with SOLID-STATE electronic ignition. Result: 400 hours without a glitch. I don't trust magnetos, having had my share of magnetos failures and incidents (I don't remember having had an ignition failure in a car in 18 years, by the way), and I feel much, much safer with a solid state electronic system. The ignition pick-ups were redundant, so only the coils and spark plugs were not. And of course, the electrical system has been well thought! Then, I started wanting more power, and I got myself a reasonably improved VW engine: 2.4 liter instead of 2.0 liter. I did not want a bigger one, because I want reliable power, not hot rods! This is where I installed a fully dual redundant solid state electronic ignition system. No single failure can lead to catastrophic failure, save for the carburetor, but I am told that Lycomings and Continentals are like that too. This, coupled with a decent, redundant, well protected battery system, would probably be certifiable. And I see no reason why it would be less reliable than a certified engine, quite the contrary. I am happy the solution I have, and even more happy with its cost. Now, what I really dream of, is a 4-seater, twin engine plane, powered with two state-of-the-art turbo-diesel engines, burning 5 liters an hour of Jet-A1 each!, all that for the price of 1 Lycoming engine... and I know it's technically feasible. Serge Vidal KR2 ZS-WEC Tunis, Tunisia
