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Does anyone have a typical operating cost for a PA31 versus say a King air? Or better yet, the F406 ????
Difficult to say because it depend how many hours per year you are able to fly and also where those are based. I do not have experience for such planes you asked. But if it can help you, our running cost for C404 are USD 690 per hours versus USD 990 of B200. Those are calculated on the same basis and proportionately to effective crew costs, allowance, maintenance, engine and propeller reserves, insurance and liability, revenues, equity and bank loan if there.
Regarding the number of the engine, of course two are better than one, especially in IMC. But <<better one reliable than two unreliable>>.
Guys do not forget that we are talking about of light twins ...very low single engine performance… especially for charter when always we are flying fully load.
Cheers.