Highly Evolved

The Lancair Turbine Evolution may be the ultimate Experimental—a magic carpet with the speed and range to go anywhere in the country in a day.

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The short description of the Evolution goes like this: It is a comfortable, four-place, pressurized, de-iced, single-engine turboprop that will haul two 200-pound passengers and two 70-pound passengers with full fuel. It will take them over 1000 nautical miles at Flight Level 280 at over 320 mph at better than eight miles per gallon. All this in an airplane that is remarkably easy to fly given the capability. What else is there to say but, “Wow”?

Kitplanes® flew and reported on the prototype Lancair Turbine Evolution early in its development, and we were impressed. But it wasn’t finished. We also flew the piston Evolution and reported that the company had done a great job of finishing out the airframe and interior appointments, but the electronically controlled engine was still a work in progress. When our chance came to fly Lancair’s Turbine Evolution, our expectations were pretty high about what we would find in the finished airplane. And what we flew was not just a finished airplane; what we found was an airplane that was complete.

It’s clear from the exhaust pipe whiskers near the nose that this is a turbine-powered airplane.

Sizing it Up

When thinking about an airplane with these capabilities, a mental picture develops. The airplane has to be big; and as the Evo taxis up, it has a big presence on the ramp—until it parks next to another airplane. With a 36-foot-8-inch wingspan, it is actually comparable in size to a Cessna 172.

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But size is about the only thing the airplane has in common with the Cessna. Composites allow a designer to build an airplane that passes cleanly through the air, instead of just moving easily through the manufacturing process. The carbon fiber fuselage of the Evolution doesn’t seem to have a flat surface anywhere. Looking at the airplane from head-on, it appears that it would simply part the air and pass through it, rather than push it out of the way.

Turbine Power

The exhaust stacks on each side of the nacelle, located directly behind the propeller, are a trademark of the reverse-flow PT6-135 engine. PT6 engines fit into three groups—small, medium, and large—and the -135 version falls into the middle category. It is unique in that the air enters the engine in the back, is compressed, and moves forward into the hot section where fuel is introduced and the work is done. The first turbine power wheel powers the compressor section and the two subsequent power turbine wheels drive the propeller. This provides for easy inspection, and should a propeller strike occur, only the power section need be removed and inspected or repaired.

With the low-stress this airplane puts on the dependable Pratt & Whitney PT6A, it is unlikely that the owner will have engine overhaul costs in the foreseeable future.

The main landing gear tires are 18×4.4, a narrow, high pressure tire that is used on the nosegear of the T-38 Talon. This type of tire would be susceptible to skidding and flat-spotting if the brakes were used to stop the airplane, but the Pratt & Whitney PT-6-135 has beta and reverse capability on the propeller, making brakes needless except for steering at low speeds and during run-ups.

Lancair is an OEM dealer for Prattt & Whitney engines, and this means that Evolution customers who choose to install a factory-new engine enjoy worldwide factory warranty, support and repair. Repair is important when needed, but the best scenario is never needing it. The PT6 engines are among the most dependable sources of power ever developed. In pumping and power generation applications, these engines run unattended without service for years. This kind of dependability is an important factor and provides peace of mind when choosing an engine for a single-engine airplane.

You know you’re looking at a speedster when the trim tab linkages have drag-reducing fairings.

The recommended service intervals for the PT6-135 call for an 1800-hour hot-section inspection and a 3600-hour major overhaul. However, in an Experimental/Amateur-Built aircraft, those requirements are not legally binding. Because the engine will normally be operating considerably below its maximum temperature and torque values, hot-section inspections and overhauls could be done on an on-condition basis, instead of time in service. This could dramatically lower the engine reserve operating costs.

Lancair Director of Marketing Doug Meyer said, “It is unlikely that the average owner will ever have to do a hot section inspection or overhaul if they start the engine correctly and run it conservatively.”

Engine reserves are not the only place where the Evolution would shine in operating cost when compared to other turbine aircraft. Certified turbine aircraft often have numerous life-limited parts that must be replaced after specified flight or calendar times in service; an Experimental does not. This does not mean that the rigors of high-altitude and high-speed flight do not take a toll on airframe parts. Turbine aircraft are held to a higher standard in the certification requirements than piston aircraft for a reason. The stresses are higher and the consequences of failure greater, so rigorous and thorough maintenance is still a must.

Gull-wing doors make structural sense and add a bit of panache to the airplane on the ramp.

The reversing Hartzell prop has deice boots to complement the de-iced wing to make the Evo an all-weather airplane.

A Special Type of Kit

The wings of N698W were smooth and the only hint that the airplane was ice-protected were a few ripples in the paint on the leading edges. There were no boots and no TKS strips. The Evolution uses the ThermX electric inductive graphite panel installed under a thin film of composite. Some 7000 watts of power at 70 volts sends a jolt of heat through the skin that melts a strip and knocks the ice free of the wing. The result is a leading edge that can be painted, thus preserving laminar flow. Standard electric boots heat the four-blade, full-feathering, reversible Hartzell propeller and a small glycol tank keeps the windscreen clear.

Laminar flow is important to efficiency; and the finish on the wings, tail and fairings can only be described as perfect. The carbon fiber composites are formed into an airframe that has the feel of a monolith, as if it were molded in one piece. In reality, it is built in major parts and the parts are carefully joined. The fuselage includes both front and rear pressure bulkheads, windows, and the vertical tail. The wing is a single part, as is the horizontal tail.

This is not a typical Experimental kit that you commence in your garage. Because of the complexity of the airplane and the tooling required, the build process begins at the factory. The customer stays for an initial two-week period. During this time, the critical systems are installed and the major components are sealed up in the factory tooling to ensure design conformity. At the end of that period, the kit leaves the factory and the customer takes the project home or to a commercial assistance shop. There are several shops around the country that are qualified to assist the builder with completion.

The wings taper to a miniscule tip, not much bigger than is needed to mount the LED lights.

The kit price of $545,000 includes most of what is required for completion except engine, prop, interior, firewall-forward kit, deice, and paint. The instrument panel, including the Garmin G900 EFIS and GFC 700 autopilot system are included. When all the bills are paid, the total is going to be $1.3 to $1.5 million. The typical build process is seven to eight months, from the down payment to first flight, if the builder is committed. Then it is time for an inspection and first flight.

The kit price includes three days of initial training and the first year’s recurrent training. The bugaboo in the system is that the FAA doesn’t allow training during Phase I flight testing. Some FSDOs have granted Letters of Deviation Authority to do this, but it is not common. That means either getting some training in another airplane, or hiring a test pilot to complete the 25 or 40 hours of required Phase I flight testing.

The Evolution’s flowing lines cheat the air from creating drag. These can only be constructed from composites.

The Purpose is to Fly

When the test period is complete, the purpose of an Evolution is to load up and go. With that in mind, Doug Meyer and I took off from San Carlos, California to take the Evolution to altitude, where it is most at home.

Starting a turbine is a straightforward process. Read the checklist, turn on the master, ignition and fuel pump, and then push the starter button. When the gas generator section rpm, or N1 exceeds 15%, move the condition lever forward and monitor the temperatures. If the temps stay cool, when the engine reaches 51%, let off the starter button, turn on the generator, and call for a taxi clearance.

The forgiving trailing beam maingear mounts skinny, high-pressure tires to fit in the thin wing. The reversible prop provides plenty of stopping power to complement the standard wheel brakes.

The Evolution we flew weighed in at 2507 pounds, but even at the gross weight of 4500 pounds, it is a light airplane with a big motor. Taxiing with the engine at idle and the prop on the low-pitch stops, it will accelerate without braking. Brake energy is best reserved for an aborted takeoff; brakes are more expensive than simply pulling the throttle over the idle gate into the beta position, which reduces propeller pitch, or farther, which introduces negative pitch and adds power for reverse.

Steering is accomplished, like nearly all new designs, with differential braking. Like it or not, the trend away from nosewheel steering seems here to stay, so we might as well accept it. The good news is the rudder is effective at slow speeds; and unless the crosswinds are strong, little brake is needed to steer.

The fun begins at the runway. Meyer recommended using 1250 pounds of torque for takeoff, just under half of the 2080 pounds available at full-rated 750 hp. Takeoff in a turbine normally requires monitoring both temp and torque, but at the low power used, I doubt there would ever be a day, or high enough airport, that temps would become an issue at that power setting.

The swiveling nosegear provides tighter turning capability than one would get in a steerable unit.

Even at slightly more than half power, the right rudder required is significant. Any unwillingness to push the pedal would result in an excursion, but it was smooth, honest and tracked true. Any fuel imbalance will become apparent at rotation—the airplane will roll slightly toward the heavy wing, but a quick trim adjustment will resolve it.

Sadly, in the complex airspace of the Bay area, pushing the power up immediately after takeoff to sample the spectacular climb performance was not an option; but the G900 synthetic vision depicted the airspace restrictions, and we leveled off quickly and pulled the power back to maintain less than 200 KIAS under the Class B.

Soon we were stepped up to 4000 feet, clear of the Class B and able to climb. Pushing the power up to a conservative climb setting of 750° C and a cruise climb airspeed of 155 KIAS, the airplane was a skyrocket with over 3000 fpm climb.

At 15,000 feet, the autopilot was maintaining 155 KIAS perfectly and the climb rate was still 1800 fpm on 42 gph. At 17,500 feet, we leveled off to see what a VFR pilot could accomplish without filing or flying IFR. The airplane settled at 277 KTAS on 46 gph. This is certainly not how the airplane was intended to be flown and much less efficient than what we would see at altitude, but it’s still an option.

What was noticeable, especially in climb, was how quiet the airplane is. No leaks, no squeaks, no aerodynamic rumble—just the soothing hum of the big Pratt pulling us skyward. The cabin pressure was climbing considerably slower than we were. It is controlled totally automatically by the touch-screen microprocessor that operates most of the systems in the airplane. Soft keys on the screen drill down to menus for automatic control of cabin heat, cooling, pressurization, lighting and some electronic circuit breakers.

Going for Altitude

Resuming the climb, we soon leveled at FL280, the maximum altitude allowed for non-RVSM traffic. This is a harsh environment. The atmospheric pressure outside would only provide consciousness for two to three minutes, should the cabin depressurize. But inside, it was comfortable, with a cabin altitude of 8500 feet and 72° temperature, with a 6.2 psi cabin differential.

Many turbine airplanes cold soak at this altitude. The armrests and other metal fixtures that are attached to the outside feel cold and suck the heat out of the cabin and crew. While we did not stay long at FL280—there was no sense of that in the Evolution—it was comfortable and quiet as we accelerated to cruise speed.

With the power lever set at the first limit, we attained maximum N1 or 101.2%; the G900 panel reported a true airspeed of 282 KTAS, burning 38 gallons per hour. While that is somewhat short of the 300 plus that Lancair hoped for when the Evolution project began, it is still an impressive number. At 282 knots, or 325 mph, the world starts to become a small place. Draw a 1000 nautical-mile radius around your home airport and imagine leaving after breakfast to eat lunch anywhere inside the circle. Airplanes with this kind of speed change a pilot’s perception of the world and what is possible. There is a word for it: Magic.

Hand Flying

All the way up, I had been dutifully collecting data and managing the flawless performance of the autopilot. Now it was time to fly. One push of the red button on the left horn of the yoke and the airplane was mine. Many turbine airplanes are very unpleasant to fly at higher altitudes. They are sluggish and slow to respond. We asked for clearance to maneuver and rolled into a 45° bank steep turn. Effortless.

We turned around and headed down. Below FL180, we cancelled IFR, pulled the power back and slowed to gear extension speed of 150 KIAS, slowed further to 140 KIAS to select full flaps and pushed the nose over into an emergency descent of over 6000 fpm. The deck angle was breathtaking. At 13,000 feet we tried stalls and slow flight—both clean and dirty they were benign, well warned with predictable recoveries.

We worked our way back through the airspace maze to San Carlos, using the G900 to meet up with our photo ship for pictures. Joining the downwind, once the airplane was configured, it slowed instinctively to the recommended downwind speed of 100 KIAS. Ninety on base and 80 on final, and in spite of a gusty crosswind very close to the max demonstrated limit of 20 knots, the airplane touched down on one tire, hopped once, and set down again on both. We retracted the flaps and it stayed firm on the ground.

After a quick briefing, and as the sun was getting low in the sky, we launched again on the wing of an A-36 Bonanza with KITPLANES® photographer Richard VanderMeulen. We toured the Bay area and shot stunning images of a beautiful airplane as the sun settled into the sea.

The three power levers shouldn’t confuse the recip pilot, except that the propeller can be reversed and the red knob is condition, not mixture. The black knob still makes the airplane go fast.

There is no better way to assess the handling characteristics of an airplane than some good formation flying. The A-36 with its door off was holding 120 KIAS and as we slid under the belly of the Bonanza to join on the outside of a shallow turn, I pulled the airplane up into right echelon, pulled the power back, and the big prop went to flat pitch. The airplane stopped smartly in position.

The Garmin G900 panel comes fully integrated, bench tested, and ready to plug into the finished wiring harness supplied with the kit.

The standard sidestick controller gives the pilot an uncluttered view of the panel and includes critical switches on the grip.

The pitch forces were comfortable and the trim response was correct. The ailerons on the prototype and the piston airplane had been heavy, but a recent redesign lowered the forces. While I thought they were perfect, the plan is to make them slightly heavier before finalizing a new design that will retrofit to the flying airplanes if desired. Formation flying was wonderful! It was difficult to restrain myself (both in the aircraft and on these pages) from being effusive about the pure joy of flying an airplane that has the ability to make a big world small­—and flying fun.

As darkness fell over the city and the lights came up, we turned back to the airport. By the time we landed, it was hard dark and the crosswind had subsided. Again, the airplane settled effortlessly to 100, 90, and 80 on final, to a smooth touchdown on the tiny tires—a little reverse and it was done.

The folks at Lancair are extremely pleased that Garmin allowed them to install their GFC 700 autopilot in the Evolution. Garmin’s concern is whether or not kit airplanes are consistent enough that their software will fly the airplane well. The definition of quality is low variability, and Lancair should be proud of achieving that.

The definition of performance is finding the balance between all the competing factors that must be compromised to build an airplane that is useful. What the folks at Lancair should be even more proud of is that they have designed an airplane that is complete.

Lancair Turbine Evolution


Doug Rozendaal’s pilot certificate requires two cards and includes ratings in business jets, WW-II bombers, transports and fighters, as well as seaplanes, gliders and the coveted “All Makes and Models of Single and Multi Engine Piston Powered” endorsement. He holds a low altitude aerobatic waiver and flies airshows in the P-51, T-6, Rocket, and RVs.

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