Mooney M20K 252 / Encore (1986-2001)

The M20K 252 is the automatic-wastegate successor to the 231 -- Mooney kept the same long-body airframe and the same basic TSIO-360 engine family but replaced the 231's pilot-managed wastegate with an automatic one, removing the 231's single biggest operating workload (and its single biggest pre-buy risk item) without changing the airframe. Production ran 1986 to 1990 on TCDS 2A3's S/N 25-1000 thru 25-1999 block.

Mooney revived the automatic-wastegate turbo M20K in 1997 as the Encore, on S/N 25-2000 and up, with the engine bumped to the TSIO-360-SB2 at 220 HP and gross weight raised to 3,130 lb for the great majority of that block (see "A serial-range wrinkle worth knowing about" below) -- after a gap of several years in which Mooney's turbocharged-single duties were carried by the Lycoming-powered M20M TLS/Bravo instead.

Cruise, fuel burn and range are read from one worked example, repeated consistently across three Section V charts of the SAME primary POH (Manual No. 1236, Rev. B, confirmed via Section II to carry the 252's own TSIO-360-MB1 engine and 2,900 lb max weight): 22,000 ft pressure altitude, -10C OAT, 65% power, 2,400 RPM. At that condition: 183 KTAS, 11.0 GPH, and 996 nm range (with 45-minute reserve at cruise power, per the chart's own stated range definition). This is a genuinely stronger performance picture than the 231 page carries -- the 231's own cruise/climb/stall figures had to fall back to a 1980 AOPA press report because no correct-variant POH was obtainable for it, and its range_nm is blank outright because rule 29 bars a press-sourced range regardless of source quality. This page's range comes from the airplane's own primary handbook, so that bar does not apply.

This catalogue's convention for turbocharged airplanes is to store the high-altitude cruise figure, and 22,000 ft is close to this airplane's own 28,000 ft ceiling -- a meaningfully higher ceiling than the 231's 24,000 ft or the Encore's own 25,000 ft, which is a genuine, certificate-sourced point in the 252's favor for anyone planning to fly above weather regularly.

Stall speeds (Vs1 61 KIAS clean, Vs0 59 KIAS landing configuration) are read from the same POH's Section V stall-speed table at 2,900 lb (max gross), 0 bank -- a clean printed table, not a nomogram, and the highest-confidence figures in this page's POH sourcing.

Not yet transcribed from this same primary document: rate of climb and all four runway distances. The relevant charts exist in the POH (pages 5-14, 5-15, 5-16) and are named in the saved passage; the climb chart specifically was rendered but not reliably legible at the available scan quality this session. None of this is barred by rule 29 -- it is simply not yet done, and a future session (or a cleaner copy of Manual No. 1236) should be able to finish it without new research, only more careful transcription.

The Encore's own performance is not sourced at all. The POH obtained this session is explicitly the 252's own (TSIO-360-MB1), and per rule 2 none of its figures are used for the Encore's different (SB2, 220 HP) engine. The Variants table above carries only the Encore's certificate-sourced weight, power and ceiling.

• Flight Training (2): Not a trainer -- complex, fast, and turbocharged, though the automatic wastegate removes the 231's extra workload.
• Backcountry (1): Low-wing retractable, no business off pavement.
• Business Travel (9): The automatic wastegate makes this a lower-workload high-altitude platform than the 231 for the same basic mission -- point the airplane at weather and climb over it without hand-flying the wastegate.
• Aerobatics (1): Not certified.
• Cross-Country (10): 183 KTAS at 65% power with a genuine 996 nm range (this page's own primary-sourced figures) makes the 252 a serious point-to-point airplane, and the highest certificated ceiling in the whole M20K line.
• Cargo Hauling (3): Same short-body-cabin limitation as every M20 in this weight class; useful load is not currently sourced (see above).
• Local Fun Flying (6): Automatic wastegate removes some of the 231's hands-on engagement, scored the same as the 231 for that reason.
• Surveying (4): Low-wing visibility limitation common to the whole M20 line; the turbo's altitude advantage is wasted at survey altitudes.

Parts availability "fair" -- same general Mooney parts-support picture as every other M20 (LASAR as primary aftermarket source), with the same turbocharger-and-related-hardware caveat as the 231. Mechanic familiarity "specialist."

Not independently sourced this session -- see the validator_exempt entries above. The stored bands are this session's own positioning estimate (between the 231's band and the Ovation's, reflecting the 252/Encore's turbocharged-plus-automatic-wastegate market position) rather than a Vref/Bluebook or Controller/Trade-A-Plane read. This is the weakest area of this page and should be replaced with a real price pass before this page is treated as verified.

Universal Mooney pre-buy items apply (Johnson-bar or electric gear rigging, elevator balance weight, fuel bladder deterioration). 252/Encore-specific, carried from general Mooney turbo-single knowledge and NOT independently re-verified this session:

1. Automatic wastegate controller condition -- less pilot-workload risk than the 231's manual wastegate, but the controller itself is a maintenance item; verify service history.
2. Turbocharger shaft play and oil seepage -- inspect at annual, same as any turbocharged Continental.
3. Cylinder condition -- borescope and CHT/EGT trend review standard on any turbocharged Mooney pre-buy.
4. Note 21 retrofit status on early-Encore-serial airframes (25-2000 thru 25-2012) -- confirm from logs whether the airplane is mechanically a 252 or a true 220 HP Encore; see "A serial-range wrinkle" above.

Retractable, high-performance, turbocharged single -- same general category as the 231, with a modest premium credit in practice for the automatic wastegate's lower over-boost risk (not independently priced this session).