TBM 910 Versus SF50 Vision Jet Theress gonna be a showdown

The six-seat, French-built turboprop goes from a standing start to rotation speed in 16 seconds compared to 23 seconds in the jet, and the TBM 910 covers about 1,200 feet during its ground roll compared to 2,000 feet for the SF50. Once airborne, the TBM climbs at a steeper angle (15 degrees compared to 10) and reaches pattern altitude first.

The crew of the SF50 had expressed some concern at our preflight briefing that the 100-foot-wide runway at Frederick Municipal Airport (FDK) in Maryland might not provide sufficient width if the SF50 were to pass the TBM on the takeoff roll. But that worry faded as the jet fell farther and farther behind.

“We’re leaving them in the dust so don’t worry about being overtaken by the SF50,” I told Matt Desch, the pilot and owner at the controls of the TBM. From my vantagepoint in the right seat of the turboprop, I had a clear view of the jet. “It’s fallen so far back that it’s completely out of sight.” That reality was echoed by the SF50 crew.

“[The TBM] takes off a lot faster than us,” said Amanda Farnsworth, pilot and owner of the SF50. “I mean, a lot faster.”

The takeoff contest was such a clear and convincing victory for the TBM that there was some discussion among the fly-off crew that other events comparing the two airplanes’ speed and agility may be equally one-sided. But the best was yet to come for the SF50, and it would soon prove more than a match for the TBM in other categories.

Grudge match

Pitting a turboprop and a jet against each other may seem like an odd pairing, but it follows a certain logic.

The TBM and SF50 are both popular and aspirational models for piston pilots looking to move up to turbine aircraft. They both offer 300-knot cruise speeds, pressurization, 31,000-foot service ceilings, and 1,000-plus nautical mile range. The most current models are equipped with modern Garmin avionics and safety technology such as envelope protection and one-button Autoland system. The SF50 also includes a whole-airframe parachute. The two airplanes also command comparable prices on both the new and used markets with fully optioned aircraft exceeding $4 million.

There are, of course, many major differences. The TBM is mostly metal while the SF50 is primarily carbon fiber. The TBM is narrower and offers club seating for passengers while all (up to seven) SF50 seats face forward. The TBM has straight landing gear while the SF50 uses a more forgiving trailing link design.

Their origin stories also contrast sharply. The TBM was born of a French/U.S. consortium that included Mooney (that’s the M in TBM), and its 700 model first flew in 1988 and was FAA certified in 1990. Daher has continuously updated the original TBM design with more powerful Pratt & Whitney PT6 engines, Hartzell composite propellers, and winglets that deliver higher speed, quicker climbs, and longer range. The latest avionics and creature comforts, such as a pilot’s side door, have kept TBM at the forefront of an increasingly competitive category for single-engine, six-seat turboprops, which includes U.S. manufacturers Piper with its M700 Fury and Epic with its E1000GX.

The SF50 Vision Jet began as a clean-sheet concept and first flew in 2008, then was put on the back burner during the Great Recession in 2009. Cirrus finalized a conforming prototype in 2014 and obtained an FAA type certificate for the SF50 in 2016. The SF50 has proved remarkably popular in the marketplace since then with more than 500 deliveries and a steady backlog of new orders. The SF50 also proved that pilots of single-engine piston models can successfully move to jets without multiengine or turboprop experience.

Time to climb

The two competitors are flying line abreast at an altitude of 2,500 feet and 150 knots to begin a climb contest. On the aircraft radio, TBM pilot Desch provides a countdown.

“Three, two, one—go!”

Both airplanes add power and pitch up—and the SF50 pulls ahead while also ascending at a higher rate. Both airplanes are moderately loaded with three occupants and two-thirds fuel on a warmer-than-standard day.

Desch raises the TBM’s pitch attitude to 15 degrees in an attempt to zoom to the target altitude of 10,000 feet, but nothing he does can change the outcome. The TBM is climbing at about 2,000 feet per minute at 130 KIAS through 6,000 feet while the SF50 is pulling away at 2,500 feet per minute and 150 KIAS. The jet crosses 10,000 feet about 15 seconds before the TBM gets there.

advantage: SF50.

The published specifications for both airplanes say they can get from the surface to their 31,000-foot service ceilings in about 20 minutes or slightly less, but the SF50 is the clear winner of this abbreviated, relatively low-altitude event.

“I’m a little surprised and kind of disappointed, but there’s no question your airplane climbs faster at this altitude,” Desch confesses on the radio. “That was a thoroughly impressive display.”

Drag race

The TBM and SF50 are flying side by side at 9,500 feet about three miles behind the Beechcraft Bonanza A36 that’s serving as our photoship when the drag race begins. The two airplanes are indicating about 180 knots, and both pilots push the power up at the same time.

The TBM accelerates to 222 KIAS but it’s not enough as the SF50 pulls ahead and pulls away. By the time the SF50 passes the Bonanza, it’s indicating 250 knots and has opened a roughly 10-second lead. We repeat the contest from five miles and the result is the same. The SF50 wins the drag race going away.

That result is surprising given the fact that the TBM 910 claims a top speed of 330 KTAS at 28,000 feet compared to 311 knots for the Vision Jet. But at 9,500 feet (and a density altitude of about 10,000 feet) the SF50 wins decisively.

advantage: SF50

Slow motion

Slow flight comes next and both airplanes decelerate together.

With flaps and landing gear retracted at an altitude of 8,500 feet, the TBM and SF50 gradually slow in unison.

Both airplanes are equipped with Garmin’s “electronic stability and protection” (ESP) system designed to prevent pilots from exceeding preset limits. ESP monitors aircraft performance at all times and activates the autopilot automatically to prevent aerodynamic stalls or overspeeds.

Both airplanes are equipped with unignorable stall warning and recovery systems, and they both activate the same way. In level flight the TBM’s high angle of attack caution light comes on at 90 knots and an aural “Stall! Stall!” warning activates at 88 knots followed by a stick shaker. The SF50 gives similar indications at almost identical speeds, with a high-AOA warning at 90 KIAS and aural warnings activating at about 87 knots.

Both airplanes are remarkably stable at low speeds and high angles of attack, and both provide excellent safety tools aimed at avoiding loss of control. The automated systems take over one knot apart which is within the avionics system’s margin of error.

advantage: None

Roll rate

Both airplanes are designed to be stable instrument platforms yet responsive and enjoyable to hand fly.

Aspects like control harmony and responsiveness are hard to quantify, yet pilots recognize and appreciate when designers get these characteristics just right. The SF50’s high thrust line (due to its top-mounted engine) creates a nose-down moment at low airspeeds and high power settings, yet designers have done wonders at balancing out these forces.

The SF50’s sidestick control feels natural and easily manageable whether the pilot is turning to their “forehand” or “backhand” direction. The TBM has a conventional control yoke that’s very well balanced in pitch and roll. Neither airplane has any discernable adverse yaw.

One area that’s objectively measurable is maximum roll rate. It’s fairly sedate in both airplanes throughout their normal speed ranges. Video of each airplane performing a breakaway from the Bonanza photoship when flying at 135 KIAS showed almost no difference in roll rate. At full aileron deflection, they both roll slightly more than 30 degrees per second, or two seconds to reach 60 degrees of bank.

advantage: None

Stopping power

The final flyoff event is a short-field landing and, like the short-field takeoff, the result isn’t close.

The TBM and the SF50 both fly 80 knots on short final in the landing configuration, and they both touch down at about 72 knots. But the TBM’s reversible, five-blade Hartzell propeller gives it tremendous stopping power, and it comes to a halt after a ground roll of about 800 feet with moderate braking (and a quartering headwind of 11 knots with gusts to 16).

The similarly loaded SF50’s wheel brakes provide its only stopping power—and it has the additional disadvantage of working against a jet engine that’s putting out significant residual thrust at idle power. The trailing link landing gear is highly effective at cushioning the touchdown, but without speed brakes, spoilers, anti-skid brakes, or reverse thrust to hasten the stop, the SF50 rolls out in about 1,200 feet. That’s short for a jet, but nowhere near a turboprop.

advantage: TBM

Conclusions

Going into this flyoff, I anticipated a TBM clean sweep. Any turboprop has inherent advantages over a jet in terms of quicker acceleration and deceleration, and the TBM’s sleek shape and aerodynamic refinement make it a stellar high-altitude performer, too. But the SF50 proved faster in our low-altitude drag race, more muscular in climb, and more stable in slow flight than expected.

In general, the TBM and its single-engine, turboprop peers are more expensive to buy but more fuel efficient to operate than pure jets. Turboprops can fly in and out of shorter fields, carry heavier loads, and travel longer distances on the same amount of fuel. Pilatus pioneered the single-engine turboprop business aircraft category with its PC–12 and proved the concept beyond the utility Cessna Caravan (a.k.a. “turbine Suburban”) and Daher’s Kodiak. TBM brought speed and sophistication in a six-seat package, and Piper and Epic have made that 300-knot club especially competitive. The arrival of the Beechcraft Denali will surely add to the innovative and prestigious mix.

So far, the SF50 remains the only FAA-certified, single-engine GA jet. Piper, Diamond, and Eclipse abandoned their own single-engine jet programs long ago, yet the success of single-engine turboprops and the SF50 seems to indicate the market will embrace turbine airplanes with a single powerplant.

Will other manufacturers dust off their single-engine jet designs and enter the fray? Will a new entrant like Stratos Aircraft in Oregon succeed with its own single-engine jet design? Can designers overcome the inherent jet disadvantages and create something with turboprop performance and efficiency? If so, the market appears ready for it.

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