Jet Powered Skylane
For whatever reasons it might have, Cessna prefers to refer to the new Skylane as a jet-A powered airplane and will go out of its way to avoid using the “D” word. For some folks diesel technology conjures up images of Soviet-era truck motors. Today, though, diesel technology has gone upscale. Turbodiesels from Mercedes, Volkswagen and Renault (the original co-developer of the 305 engine) are clean, powerful, quiet and sophisticated.
When it comes to the new Skylane, that’s the image Cessna is hoping to project, and based on my experience flying the new model, it is on track.
There was remarkably little that had to be done to the Cessna 182 to accept diesel power. There’s a new engine mount, of course, as well as a new squared-off cowling, which gives the JT-A an aggressively modern air. Very importantly, there’s no gear box to reduce the rpm of the prop, as there are on two existing diesel engines from Austro and Centurion (the former Thielert), both of which are derived from automotive products. The Cessna installation also did not require a fuel radiator. Such a device is sometimes necessary to cool off bypass fuel (fuel that gets pressurized for injection but is not needed and, so, is returned to the fuel tanks). Because the Skylane’s wings are sheet metal — the fuel tanks are of the wet wing variety — there’s not the same Thermos effect as on some composite airplanes. The wing of the Cessna is, in essence, an effective enough fuel cooler.
There’s also a new carbon fiber Hartzell three-blade prop that is light and responsive, turning at just 2,200 rpm. There’s no prop control. The computer keeps it at an optimum setting for the conditions and the power commanded by the pilot. The new prop helps keep the entire weight penalty for the diesel at just 15 pounds.
Flying the JT-A
After departing from KICT with Cessna test pilot Charles Wilcox, we flew the 182 JT-A throughout its performance envelope.
Climbing out from Mid-Continent, I put the airspeed on best rate of climb, which is 82 knots, and watched as the airplane climbed surely and steadily. Because the SMA model in the new Skylane is a true turbocharged engine, we saw 100 percent power up through 10,000 feet while burning just 12.1 gph, this compared with between 28 and 20 gph in the climb for the gas piston model. As great as the low fuel burn is, the engine management is at least as important an improvement. For climb you set power at 100 percent simply by pushing the lever all the way forward. The computer takes care of setting the rest of the variables to give you that percentage of power.
Fuel flow is a big deal, because it’s such a little deal. At 90 percent power — set the power using the Garmin G1000 MFD, coming soon to the JT-A — you’ll see a fuel flow of right around 11 gph, which gives you around eight hours of endurance. At 150 knots true airspeed, that will give you around 1,200 nautical miles of no-wind range. Pull the power back even more and you can go at reasonable speeds for extremely long distances. Trips of 1,500 nm are quite possible, though you won’t get there quickly at that fuel burn. The optimum scenario will be at 10,000 to 12,000 feet msl, where an 1,100 nm range at high power with reserves is likely.
