A big advantage to the turbo is the ability to run it at very high power settings LOP with cool CHTs and low ICPs. In these scenarios, the engines last a long time and are quite efficient in fuel burn while resulting in higher TAS.
If the turbocharged engines are operated according to the POH, engine life is shorter due to higher CHTs and ICPs. If one appropriately runs them richer ROP to offset this negative issue, range will suffer and the cost of the extra fuel will be significantly more.
I recognize that few SkyMaster owners operate their engines in this optimal manner, but the scientific facts are compelling. Few Baron owners are operating ROP any more and fewer and fewer Twin Cessna owners are doing so. Almost zero turboCirrus, or turbo Bonanzas are operated ROP any more.
In an aircraft where cooling the rear engine has been a challenge, it remains a mystery to me why the advantages of optimal mixture management have not caught on. The turbo SkyMasters are the perfect airplanes to be operated this way.
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Walter Atkinson
Advanced Pilot Seminars
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