Socata's TBM 850

When French airframer EADS Socata unveiled a souped-up version of its venerable TBM 700 single-engine turboprop in 2005, it billed the aircraft as the "anti-very light jet." Indeed, the TBM 850 will carry more payload, fly farther and typically complete a 500-mile trip about as quickly as a twinjet VLJ. It will also burn only about half the fuel and climb like a rocket. And it's a great short-runway performer.

But at $2.84 million (that darn Euro), the TBM is priced on par with entry-level twinjets with more capacious cabins, such as the Cessna Citation Mustang and Embraer Phenom 100. It is only marginally less expensive than bigger turboprops like the single-engine Pilatus PC-12 and Beechcraft King Air C-90GT twin, and it costs $1 million more than the Eclipse 500 and Adam A700 very light twinjets.

Largely due to the efficient way it takes power away from the engine to run the cabin pressurization and heating systems, the TBM 850 is 28 knots faster than its predecessor and boasts a top speed of 320 knots-only about 20 knots slower than a Mustang. But to reach maximum fuel economy, a jet needs to climb to the higher altitudes-in the 30s or low 40s-with all the faster airline traffic. The TBM zips along in the relatively less congested 20s, where the odds increase for more direct routing and, conversely, for running into more rotten weather.

With the 850, Socata missed a prime opportunity to convert to an integrated all-glass cockpit avionics system, simplify engine power management and further refine the cabin. Nevertheless, thanks to the low TBM production rate-some 400 units over the last 17 years (an average of 23.5 per year)-the model has enjoyed relatively consistent demand. Socata has increased the production rate over the last few years and says it will step up TBM 850 production to 52 this year. The airplanes are largely flown by owner-pilots, who are very brand loyal.

John Hinshaw of Frankfurt, Ind., is a typical 850 pilot-owner. He traded in his TBM 700-C2 last year for the new model and flies it about 200 hours a year. "It's faster than most [turboprop] twins and I wanted a realistic 1,000-nautical-mile-range airplane," Hinshaw said. "I frequently fly to Naples [Fla.], Amarillo [Texas] and Denver-all trips just under 900 nautical miles."

Hinshaw said the 850 burns about 10 percent more fuel than his 700, but that doesn't bother him because the 850 "flies 10 percent faster and climbs 10 percent quicker," which gives the airplane slightly better range.

An Ohio corporate pilot said his company looked at larger turboprops, such as the PC-12, King Air 200 and Piaggio Avanti, but chose the TBM 850 because of maintenance considerations. "I'm a 'keep it simple, stupid' person," he said, "and I don't have the maintenance staff to keep up with anything too complex."

Indeed, the basic TBM airframe has been unchanged for 20 years. Aside from the Piper Malibu, it is the most cramped six-seat turbine cabin in the sky. The cabin cross-section is just under four feet wide. This really is no surprise when you consider the aircraft's germination.

Work on what became the TBM started in 1973 after Mooney Aircraft Co.-a Texas manufacturer of single-engine piston airplanes-hired Roy LoPresti, an aircraft designer nicknamed "The Speed Merchant," as vice president of engineering. The company-whose offerings have cramped cabins but still rank among the fastest piston models-asked LoPresti to come up with another single-engine piston airplane it dubbed the 301. It was to be pressurized, seat six and have a 262-knot top speed.

Before the 301 could make it to market, however,  Mooney was purchased by a consortium of investors from France that dropped the project. Instead, the consortium formed a joint venture with Socata, a subsidiary of Aerospatiale based in Tarbes, France, to develop a 300-knot single-engine turboprop and threw the 301 design information over the wall. Socata used some of it.

The TBM 700 first flew in 1988 and was certified in 1990, when Mooney withdrew from the joint venture. The end product was a six-seat, 292-knot, pressurized aircraft that was mostly metal, but used some composites on the control surfaces. Mooney lives on in the model as the "M" in TBM (the "TB" stands for Tarbes).

Over the years, Socata has modestly improved the design, with better environmental controls; vapor-cycle air-conditioning; avionics upgrades; a small beverage cabinet; wider main cabin entry door well-suited for loading outsized cargo; and optional ($75,000) separate forward pilot's door.

Passengers sit in facing club-four seats and there is room for two pilots (although the airplane is certified for single-pilot use and most operators fly it that way). The passenger seat bottoms are 18 inches wide and have 22-inch-high backs. That leaves a really narrow 11-inch wide aisle. A single club table deploys from the righthand sidewall and there are power outlets for laptops. The cabin is quiet for a turboprop, but still noisier than a jet. The aft-located main door measures 3.5 feet high and 3.9 feet wide and swings up and out of the way on a pair of gas-charged springs. An electric motor drives it back down. If you require a bathroom, you need to ask the pilot to land.

Most baggage is stored in back of the rear-most row of seats behind a cargo net. A small baggage compartment with an external door in the rear fuselage will hold 77 pounds and is big enough for a pilot's overnight bag or a tool kit. An even smaller forward storage compartment, also with an external door, typically holds the tow bar and the engine inlet and exhaust stack covers.

Even as more VLJs come on line, the TBM is likely to hold an audience. As one 850 pilot said, "It's just hard to beat the efficiency." Or the speed.
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