Tuesday, May 20, 2008
Mooney Acclaim Type S: Still The Fastest!
If speed is your thing, The Acclaim Type S may be at the peak of the production pyramid
|A few inches away, the world isn’t a friendly place. I’m cruising in a new Mooney M20TN Acclaim Type S at 25,000 feet over central Florida, and despite clear skies and warm temperatures on the ground, the air is cold and thin nearly five miles above the ocean. Without the Mooney’s protective bubble of aluminum and Plexiglas, plus oxygen masks to provide supplemental O2, I’d be in trouble.|
In this case, Mooney brought in one of the grand gurus of speed innovation to accelerate the Acclaim, Curt LoPresti of LoPresti Speed Merchants (www.speedmods.com
) in Vero Beach, Fla. More than coincidentally, Curt’s father, the late Roy LoPresti, headed the design team that produced the remarkable Mooney 201 in 1976, wringing another 14 knots from the basic Mooney Executive fuselage and wing without a power increase. The elder LoPresti lived by the motto, “Life is short—fly fast.” Roy went on to become president of Mooney in 1984.
His eldest son, Curt, along with mom Peggy and brothers David and Jim have been working on Piper/Cessna/Beech/ Cirrus/Grumman American products, along with older Mooneys, for the last 20 years, and Curt was happy to apply his considerable aerodynamic skills to the new, ultimate Mooney.
“All the Mooneys are very clean designs, so there’s not a lot left to improve,” says LoPresti. “We analyzed the airplane’s drag profile and did find a few areas where we could clean up the airplane. Our calculations suggested the changes would generate about five knots more speed, and that’s about what they got.
“We discovered the most significant areas of excess drag were the nosegear and main landing-gear doors. The stock nosegear door had a bulge that was causing air to separate, creating burble,” LoPresti explains. “Mooney faired that in, creating a smoother passage for the air. The main gear doors also were a little too fat where the gear trunnion extends. Mooney also solved that problem.
“Additionally, we recommended installing a flap gap seal to keep air from leaking through the slot between the flap leading edge and wing trailing edge,” LoPresti continued. “Our final recommendation was that they remove their current flap hinge fairings, as they were causing more drag than they were curing.”
Before you can log the big numbers in cruise, you have to reach the flight levels, and the Acclaim Type S does that with dispatch. Flying from near-sea-level at Plant City, Fla., a few miles west of Lakeland, we lifted off and started the stopwatch on our climb to the flight levels.
I held a modified cruise climb of 110 knots pointed uphill, rather than Vy, in the interest of better engine cooling and improved over-the-nose visibility. ATC was willing on the day of our flight, and we were able to high jump all the way to FL250 without any level-off at interim altitudes. When I clicked the button at the top, time was 25 minutes and nine seconds, almost exactly 1,000 fpm. The rate varied from about 1,200 fpm initially to 900 fpm when I pushed over at 25,000 feet.
With such climb on tap, many Bravo and Acclaim pilots tend to fly high much of the time, especially eastbound, where the prevailing winds usually give you a push. Flying in the opposite direction, you can always opt to stay low where winds are lightest.
Standard fuel on the Acclaim Type S is 100 gallons. That’s plenty for most pilots, but for those aviators with the inclination to cover long distances at one sitting, the optional, 128-gallon long-range tanks provide truly bladder-stretching reach. Max cruise extracts about 22 gph from the quickest Mooney, so its apparent standard endurance is roughly four hours plus reserve. If you’re willing to settle for 200 knots at FL250, however, you can reduce fuel burn to just under 13 gph.
Opt for the 128-gallon tanks, and that translates to 8.5 hours of endurance and 1,700 nm of range, provided, of course, that you’re willing to sit in the seat for a full work day. Even I’m not that masochistic, but the message is clear: Any reasonable mission you can conceive, the Acclaim Type S can probably fly. Perhaps even better, if the cabin load will allow, you can buy the long-range tanks, fill them with the cheapest fuel you can find and fly an out-and-back without having to refuel.
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