MOONEY AIRCRAFT CORP. M20K

The Mooney 231, the turbocharged version of the 201 introduced in 1979, with a 210 hp Continental instead of the Lycoming. In the high teens and low twenties it will cruise at 175 to 190 knots on 12 gallons an hour, which is turboprop-like efficiency at a piston price, and it has a 24,000-foot ceiling for crossing weather and terrain. For a pilot who regularly flies long legs over the mountain west, it is a compelling aeroplane. The M20K designation covers three distinct aeroplanes. The 231 of 1979 to 1985 has the TSIO-360-GB with a fixed wastegate and no intercooler; from 1984 the LB1B version of the engine with better cooling and overboost protection was fitted, along with the sealed gear doors and belly fairing of the 201. The 252 of 1986 is a different proposition: the intercooled TSIO-360-MB with an automatic wastegate, a 28-volt electrical system, electric cowl flaps and improved gear and flap systems, and it is the one most buyers should be looking for. The Encore of 1997-98 added 220 hp and a 3,130 lb gross weight. So a 1981 and a 1987 M20K share a name and little else under the cowl.

The early 231s have a real problem worth understanding before buying. The original TSIO-360-GB installation had marginal cooling and a fixed wastegate, which made it easy to overheat cylinders and shock-cool them on descent; cylinder and turbocharger life on those aircraft was poor. Mooney and Continental improved it with the LB engine and an intercooler, and many aircraft have been retrofitted or converted to the later 252 standard — find out exactly what a candidate has. Beyond that: oxygen for everyone on long high flights, Mooney cabin narrowness, wet-wing fuel tank leaks, and a useful load of about 650 lb with full tanks, which is three adults and light bags.