In December 2005, EADS Socata announced the TBM 850, an upgraded version of its single-engine turboprop TBM 700. After some 15 years of production, three different models and more than 300 airplanes, the 700 was replaced on the production line by the TBM 850. Featuring a 1,825-shp Pratt & Whitney PT6A-66D turboprop engine flat rated to 850 shp, at maximum takeoff weight, the 850 can climb to FL 260 in 15 minutes and to its service ceiling of FL 310 in 20 minutes. At FL 260 the 850's cruise speed at maximum cruise power is 320 ktas. IFR cruising range is 1,365 nm. At FL 310 and ISA +20°C, the 850's cruise speed is more than 55 knots faster than that of the TBM 700 C2.
Although described by Socata as the "Ultimate Personal Aircraft," it offers performance numbers that virtually match-and in some cases even exceed-those of the twin-engine very light jets. The TBM 850 will have advantages including a significant reduction in direct operating costs, longer-range capability, a reduction in transition training requirements and potentially lower insurance premiums.
The TBM 850 airframe design employs fail-safe structural design techniques, including the use of multiple load paths and a crack-stopper band to maximize sub-system reliability/durability and structural life. The TBM 850 aircraft is essentially identical to that of the TBM 700 C2 model.
The TBM 850 airframe designers carefully chose a variety of aluminum alloys, high strength steel (including titanium) as well as advanced composite materials to maximize structural strength and durability while minimizing aircraft weight and both acquisition and life-cycle support costs. The majority of the TBM 850 structure is manufactured from conventional aluminum alloys. The wing spars, flap tracks and windshield frames are machined from solid bars of aluminum.
The TBM 850 cabin is 14.96 ft long and 4 ft in height and width, and offers 6 leathers seats with adjustable backrests, folding armrest and a large folding executive table in the center.
Easy access to the cabin is possible through a large electric door, stairs and a ramp. Once inside, 7 rectangular windows with pull down sunshades protect privacy and a fully automated dual zone environmental control system adds comfortable.
Cabin lighting consists of dome lights, baggage compartment lights, access stair lighting, and individual reading lights at all seats. 14/24V power outlets and storage cabinets are fitted.
The TBM 850 carries six adults, climbs to the certified ceiling of 31,000 ft in as little as 20 minutes, range over 1,400 nm with NBAA IFR reserves, and can land in a 2,100 ft strip or a mountain runway.
Before its official introduction more than two-thirds of 2006's production had already been sold. First delivery to a U.S. customer was slated to occur on February 23, 2006. Base price in 2006 of the TBM 850 was $2,576,930; with typical options and equipped for RVSM the airplane will list at $2,799,850, roughly $120,000 more than the TBM 700.
TBM 850s have an 1,825-shp PT6A-66D engines, derated to 850 shp. The derating yields better hot-and-high performance. It also lets the -66Ds produce those 850 horsepower right up to FL260-280, where maximum cruise speeds can reach 320 to 325 KTAS under optimal temperature conditions.
The PT6s used in TBMs do not have full authority digital engine controls (FADECs), so start procedures involve a few simple steps that the pilot must manually perform. However, both the -64s and -66s have torque limiters, so the chances of a ham-fisted pilot’s shoving the power lever past torque limits are minimized.
The TBM 850 was introduced with a new torque control. For takeoff and landing—using the TO flap defection—automatic torque limiting keeps torque below 110 percent. But once established in the climb you lift the flap switch up and over a detent, this disengages torque limiting, allowing the 121.4 percent torque redline, which gives the engine’s full, 850 horsepower.
Since 1998, TBMs have come with a large entry door that allows easier access to both the cabin and the aft baggage compartment; there’s another, smaller baggage compartment in the nose. When the door extends, a handrail and a set of stairs do too. To close the door, a fuselage-mounted push button activates an electric motor that starts the process. An optional pilot door ($89,350) is installed forward of the left wing root and next to the front left seat; of the 40 TBM 850s delivered in 2011, 17 ordered the pilot door. The landing gear can be extended at speeds up to 178 KIAS, the same extension speed as the first notch of flaps.
The TBM 850's G1000 features a large 15-inch diagonal multifunction display (MFD) capable of showing a wide range of information. This includes a crew alerting system (CAS) that posts warnings and sounds aural alerts. Data entry for the MFD is via a keypad mounted forward of the center console. Aft of the power controls is the fuel selector, which automatically switches tanks to prevent fuel imbalances. Four leather seats in a club configuration are standard, although an optional ($9,990) toilet can be installed in place of the left center seat.
Engine: Pratt & Whitney PT6A-66D, 850 shp