The”i”s Have It
The CTLSi delivers performance with efficiency
The light-sport aircraft (LSA) turns 10 this year. Few manufacturers have had a bigger impact on the category or enjoyed more success during this first decade than German manufacturer Flight Design GmbH, riding on the evolved wings of its composite high-wing CT microlight/sport aircraft, introduced in 1997. More than 1,700 have been delivered to date, and late last year, the company unveiled the latest in the CT series, the CTLSi, featuring the new, fuel-efficient, 100 hp injected Rotax 912iS engine. What better way to see how far LSA and this company have come than from the cockpit of the CTLSi during the 10th annual U.S. Sport Aviation Expo at Sebring Regional Airport (SEF) held this past January?
Flight Design actually had the CTLSi at Sebring in 2013, but the engine installation was still going through teething pains that delayed its official introduction, Flight Design USA president Tom Peghiny told me at the company's display area. "It's a mature system now," he said.
"I'm in love with this Si engine," demo pilot and regional sales rep Brian Boucher added, "It's so simple, so easy to operate." A 20,000-hour Airbus captain in his day job, Boucher's opinion qualifies as expert.
The family resemblance between the CTLSi and the original CT is clear, reflecting the series' evolutionary development. After its successful introduction in 1999, Flight Design debuted the second-generation, millennial CT, the CT2K, featuring a lengthened wing, and in 2004 introduced the CTSW, a faster, short-wing version, later incorporating a glass panel with Dynon display screens, a Garmin 496 and autopilot. The CTLS, introduced in 2008, brought the airframe to its current configuration, featuring a stretched fuselage, improved fuel system and composite landing gear, along with the Rotax 912S engine. The longer fuselage, extended some 18 inches, creates more distance between the wing and stabilizer for reduced yaw and more pitch stability, and allows for a larger and more aerodynamically shaped cockpit. (Full-scale wind tunnel testing was conducted at Mercedes-Benz's test facility.) The composite main gear, though heavier than the aluminum struts they replace, are much stronger and more flexible, absorbing more than 50% of the landing energy on the first bounce, while new urethane polymer shock absorbers in the nose gear help dampen shimmy and smooth-out hard landings.
LEFT TO RIGHT: 1. The 65-inch three-bladed composite Neuform propeller is ground adjustable. 2. The baggage compartment holds the BRS parachute---and 110 pounds of cargo. 3. Whelen wingtip position/anti-collision LED lights (Orion 600 series with landing light) are a popular option. |
At 100 hp, the 912iS offers no power increase over the 912S found in the CTLS, but the injected version reduces fuel consumption by more than 20%, increasing range by the same margin. Moreover, it runs on auto gas, providing more economy. "The further you fly, the more the superiority of the CTLS shows," the company says in its promotion material, noting the CTLSi was designed for flying routes like Chicago-NYC, Dallas-Charlotte, or from one side of Europe to the other.
Getting in the airplane requires no contortions. Simply park your butt on the seat, swing a leg over the stick as you swivel into the cockpit, bringing your other leg inside. With the cantilevered wing, there's no strut to avoid. The gull-wing doors, held open by gas struts, seal with an authoritative grasp when the latch is pushed full forward. Among the first things one notices once inside is the size of the cabin and the exterior visibility. At 49 inches across, the cabin is more than half a foot wider than a Bonanza. Seats are laterally adjustable and made to accommodate adults up to 6' 6" tall. The huge windshield and side door windows augmented by a pair of port windows just aft of the doors provide excellent visibility, and with the small engine cowl, there's little to obstruct vision.
With the Rotax integrated with the Dynon SkyView flight deck, one doesn't start the engine as much as start the system. First, one of the engine's two computers is brought online, performing checks on both computers before signaling the motor is ready for ignition. (During pre-takeoff run-up, the ersatz mag check is actually a re-check of the individual computers.) The OAT was in the 30s, but the engine immediately fired up, and oil temps quickly rose into the green. After engine start, the second panel screen is turned on. Be prepared to use the brakes while taxiing. The geared Rotax engine needs to maintain at least 1,820 rpm for the health of the gearbox, requiring periodic braking to keep the taxiing speed below a trot.
The new Rotax 912iS fuel-injected engine puts the "i" in CTLSi. |
For takeoff, set the pitch, turn on the aux fuel pump, advance the power and the airplane is airborne moments after the throttle reaches the forward stop. After hooking up with a Cessna 210 photo platform as the sun came up, we headed west at 2,000 feet to fly in quieter skies. Having the ADS-B system calling and displaying traffic underscored the advances in panel capabilities today's LSA offer.
In cruise, the flap is set to a reflex angle of negative six degrees, which increases airspeed; the reflex is limited to negative six degrees to keep the aircraft from exceeding the LSA cruise speed limit. Boucher adjusted the throttle to demonstrate three basic cruise power settings. Eco mode delivered about 107 knots at four gph, while 75% power yielded about 119 knots at a 6.5 gph burn. Boucher prefers the sweet spot in the middle: about 114 knots at a fuel flow of 4.5 gph. "To burn two extra gallons per hour for three or four knots is not really worth it," he said.
In addition to the fuel-injected Rotax, the CTLSi offers glass panel choices that include dual Dynon SkyView SV-D1000 display screens paired with a backup Garmin 796 MFD with dedicated SV-470 ADS-B receiver, providing synthetic vision, traffic and weather via ADS-B. No backup analog instruments are necessary, thanks to the Dynon's dual redundant Air Data/Attitude/Heading Reference System (ADAHRS) and multiple GPS receivers.
With the release of SkyView 6.0 last year, the autopilot features now include a flight director, VNAV, IAS hold, mode sequencing and fully coupled approaches. The updated SkyView also incorporates a "LEVEL" button on the panel (also menu accessible) that restores the aircraft to wings level, and holds heading and altitude when engaged. Not simply for emergencies, the LEVEL function is useful when hand-flying if you want to take a coffee break or whip out a pair of binoculars to check out something on the ground.
With onboard weather compliments of ADS-B, we could scroll out on the moving maps to look for any potential meteorological obstructions. "There's no weather between us and the Great Lakes," Boucher said, as if ready to set out on a cross-country.
Some pilots might question the need for a sophisticated glass panel in an LSA, a subject Peghiny had addressed on the ground. "Why would you have synthetic vision and an anti-collision system, and autopilot and weather, in an airplane that's only certified for VFR flight?" he had asked before answering himself. "If you truly want to use your airplane for vacation and enjoyment, you can imagine coming in late into a new airport in marginal VFR with some weather around, then all that capability becomes very, very important," he said. "Our customers believe that their safety is as important in a light-sport aircraft as it is in a certified production aircraft."
That brings up one of the next chapters in the evolving LSA story. Boucher is on the F37 ASTM International committee, which is considering regulations that would permit LSA to be used for IFR flight, if the aircraft is properly equipped and the pilot appropriately rated. "We're going to do it," he said confidently. (No regulations currently prohibit a properly equipped LSA operated by an appropriately rated pilot from flying IFR, but in practice, the FAA doesn't want LSA flying on IFR flight plans, those involved in rulemaking say.)
Touring aside, entry-level aircraft LSA are supposed to be docile and easy to fly. Indeed, CT series aircraft are used as trainers (a "Club" panel configuration is aimed at this market), so the maneuverability side of the performance envelope and stall characteristics are important considerations. Steep turns showed the CTLSi to be responsive and easily controllable. Keeping the nose on the horizon during 60-degree banked turns was unchallenging, requiring little adjustment of the electric trim. Power-off stalls at flap settings of zero, 15 and 30 degrees were equally unexciting. Any of the three flap settings can by used for landing. If the winds are blowing and more aileron authority and speed are needed, Boucher likes zero flaps, which produced a clean stall speed of about 52 mph IAS. With 15 degrees, the stall horn beep went to a solid bleat at about 42 mph, and with full flaps, the stall speed dropped to about 38 mph. In all three configurations, keeping the nose straight ahead with the rudders was also easy, the aircraft seeming to drift downward with a mild buffet rather than go into a series of oscillation stalls. The aircraft's safety is augmented by its strong carbon-fiber composite cockpit structure and the standard BRS parachute (found in all CT variants).
The cabin measures 49 inches with seats that are laterally adjustable to accommodate adults up to 6 feet 6 inches tall. |
Base price of the generously equipped CTLSi is $152,500. Popular options include Dynon's SV-470 ADS-B, Whelan LED landing and position lights, lightweight lithium-ion battery, Bose headsets, and other goodies that can bring the price up to $165,000. While the CTLS is still in production, "nine out of 10" customers select the CTLSi and the greater fuel efficiency it offers, Peghiny said.
Flight Design also displayed at Expo a limited-edition Jubilee CTLSi, a "value package" offered last year to mark Flight Design's 25th anniversary. The Jubilee includes two-tone leather seats and leather-covered console, wood-handle control sticks, and signed airframe plate, along with many of the most popular options. All 25 positions quickly sold (15 allotted for U.S. customers), and the company is now offering an "Americas Edition," which also features a bundled basket of discounted upgrades for $167,000. A Garmin GTN 750-based panel is also an option for the CTLS and CTLSi.
The wind began to pick up as the sun rose higher, whipping up whitecaps on Lake Jackson that would ultimately suspend operations at the seaplane base for the day. Making an overhead entry for a right downwind at 1,000 feet at Sebring, we were crabbed 45 degrees to compensate for what the Dynon reported as a 40-knot wind from the north. With the wind decreasing as we descended, we were high turning final, providing an opportunity for the aircraft to demonstrate how well it handled a slip. Final is flown at about 70 mph, with 60 the target speed over the numbers. Not much of a flare preceded the solid plant of the mains on the runway, as if providing an exclamation point for the 10 years it took for LSA to reach this state of development, and leading one to wonder what the next decade will bring.
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