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and consistent operation, they are fantastic workhorses. The cabin is roomy, very quiet (due to the geared engines and slow prop speeds) with enough heat and air conditioning.
The only “secret” to getting TBO, which is 1,600 hours, from the geared engines is proper and consistent power management. If more than one pilot flies the plane, you must make sure each one is operating it in the same manner. You definitely want everyone singing out of the same songbook. No abrupt power changes; either up or down. Smooth advancement on takeoff; reduce power in climb and cool slowly on descent by power reductions of one inch of manifold pressure per minute. Give plenty of time for the turbochargers to cool and slow down after landing before engine shutdown. They are spinning at thousands of RPMs and you don’t want to turn off the oil supply to them early. If this were to happen, the residual oil in the turbo will cook from the high temperature and coke up the bearings, causing the engine to be slow to spool-up. Eventually, the turbocharger will not be able to spin fast enough to produce the required engine power. Cooling the engines too quickly on descent will cause the cylinders to crack. This shock cooling will unnecessarily add to the maintenance costs and possibly cause an in-flight failure of the cylinder during the time in between compression checks.
The major systems are simple and conventional. They were already proven designs when the plane was built. Hydraulic gear with a pneumatic blow-down, back-up system and electric split-style flaps. A simple, left, right and off fuel system. There are no cowl flaps to worry about or forget. Fairly high V speeds (176 KIAS) for the gear and first notch of flaps make it easy to slow this beast down without shock-cooling the engines. Our friends at the FAA have issued relatively few Airworthiness Directives (ADs) for a model of this vintage and number of aircraft produced.
If I sound like a fan of the plane, I truly am. In my opinion, it is the best package for a corporate, charter or personal aircraft. In performance, it directly compares to a King Air C90 for a fraction of the costs. In terms of purchase price, it compares to a new Cessna 172 with exponentially more capability.
Finding the Right One
While some things are best when bought new, such as toothbrushes and chewing gum, others can only become feasible options when purchased on the used market. The era of the big piston twins offered extraordinary utility, economy and performance.
If your business needs an aircraft, talk to someone you can trust, maybe a broker or dealer who understands the
SEPTEMBER 2011
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