Tuesday, July 20, 2010
Cirrus SR22T: Turbo Without the STC
Cirrus Design now offers a turbocharged model with a factory Continental
The cabin, which measures 49x50 inches and is akin to what you’d find in a high-end luxury car, features leather seats and air bag seatbelts.
With the benefit of turbocharging, climb starts off at a healthy 1,200 fpm and loses little strength as the airplane ascends through 10,000 feet. Holding a best rate at 100 knots, the SR22T maintains an easy 1,000 fpm above 10,000 feet, 700 fpm through 20,000 feet. One of the obvious benefits of turbocharging is the ability to surmount most weather and outclimb the clouds. The Cirrus SR22T makes the most of its blower. Critical altitude, the maximum height at which the turbocharger can still deliver full, sea-level power, is 20,000 feet, so 75% power is still available at the airplane’s service ceiling.
The SR22T is a perfect example of the philosophy that retractable gear isn’t mandatory to achieve maximum performance. These days, Cirrus, Diamond, Corvalis and Cessna have all embraced fixed-gear designs. Only Mooney, Piper and Beech continue to offer production single-engine retractables. More specifically, the retractable advantage shrinks to relative insignificance as drag is reduced at altitudes above 18,000 feet. If you’re planning to fly at normally aspirated altitudes where the drag of fixed-gear is comparatively high, the weight disadvantages of retractable gear can be worth the trade. If you’ll be flying high, it’s a different story.
Cirrus models have always offered what seems a disproportionate level of speed for horsepower. In the case of the SR22T, the airplane boasts a 214-knot cruise in exchange for 18.3 gph. That’s roughly 11.5 nmpg, and remember, it’s at high cruise. At max economy settings the SR22T does even better, and it may approach 13.5 nmpg. That’s over 15.5 smpg, equivalent to the mileage of many luxury cars and SUVs and at three times the speed. Cruise numbers are based off of lean-of-peak leaning procedures.
On the subject of cruise performance, we climbed the test airplane to 9,500 feet and saw 193 knots TAS on the G1000. Most pilots of turbocharged airplanes fly below 13,000 feet most of the time to avoid having to wear a mask, and that means you can plan to see cruise numbers approaching 200 knots. Pretty impressive performance for a fixed-gear single. For those willing to strap on the O2 and loft on up to the flight levels, you can expect to see cruise numbers of 205 knots or better while clearing the highest terrain in North America and topping the vast majority of weather.
The basic Continental TSIO-550 engine is rated for 350 hp, whereas the 550K version is derated to only 315 hp. This means that max cruise can be established at 85% without violating the traditional 75% rule. Seventy five percent of 350 hp equals 262 hp, but expressed as a percentage of the 550K’s derated 315 hp, the number works out to about 85%. For pilots more interested in economy cruise to stretch nmpg to its limits, 55% at 25,000 feet reduces fuel burn to 12.7 gph while maintaining 175 knots cruise.
Perhaps the greatest attraction is simply that it’s an easy airplane to fly. Matt Bergwall played the Cirrus Perspective keyboard like a Steinway, and I’m sure it would take a long training period before I could even come close to matching his artistry (if ever). The basic functions of the airplane are as simple as it was possible to make them, however.
If you have a credit line of $620,000 (for a fully-equipped SR22T), there’s not much the newest Cirrus won’t do. Bring your brain up to speed on the G1000 and the Cirrus Perspective keyboard, and the airplane’s impressive performance and benign personality will take care of the rest.
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