Pilot Report: Latitude Livens Up The Citation Lineup

 - April 19, 2015, 12:25 PM

A hallmark of the Citation brand has been the willingness of Cessna leadership to bring out new products that compete not only with other manufacturers’ airplanes but also with the prolific Citation lineup itself. After “building a career” on two cabin cross sections conceived in the 1970s, the company acknowledged the shifting landscape of the jet market and launched the Latitude, which introduces the first new Citation cabin cross section in more than four decades.

AIN flew the Latitude on March 30 with Textron Aviation flight-test manager and chief pilot Aaron Tobias. With a spacious flat-floor cabin, efficient performance, excellent handling and a price that might poach sales from some other Citation models, the $16.25 million Latitude adds a tough choice for the buyer of a midsize Citation.

The new jet, which should receive FAA type approval shortly, is being certified as an amendment to the Model 680 type certificate, the latest model being the Sovereign+, and it shares enough features and characteristics with the Sovereign that a Sovereign+ type-rated pilot will require just differences training to fly the Latitude.

With the addition of the Latitude the Citation lineup includes three equipped with the Garmin G5000 touchscreen-controlled Intrinzic flight deck as well as the M2 and CJ3+ with the G3000-based Intrinzic cockpit. These avionics systems are easier to operate than Garmin’s first integrated system, G1000, which populates most Cessna singles, and is more like the touchscreen-controlled G2000 system in Cessna’s speedy TTx piston single. Moving up into many of the Citation models, including the company’s largest jets, is made much simpler by the familiarity that pilots gain transitioning from the G1000/G2000 to G3000/G5000 systems.

“What we set out to do was create a new midsize airplane,” said Michael Pierce, Textron Aviation manager of technical marketing, “something unique that fits in between the XLS+ and Sovereign+. And we wanted a stand-up cabin and a flat floor.”

Exterior View

During the walkaround, Tobias pointed out improvements to the Latitude airframe. The cabin door is now electrically operated, and the doorframe is fitted with a single passive compression seal, which improves dispatch reliability by eliminating the inflatable seal. The door can be opened and closed manually, and when opening is back-driven against the motor so it doesn’t drop too quickly.

There is no more “door spade” fairing, and oxygen bottles were moved from the fuselage fairing to the nose compartment and flight controls rerouted to allow for a thinner finger fairing on the belly. Baggage and nose compartment latches are a new monolithic machined style that can be closed easily with just one finger.

The Latitude wing is “essentially the same as the Sovereign+’s,” Tobias said, with the same 16.3-degree leading-edge sweep, 543-sq-ft area and smoothly upswept winglets. Wing treatments facilitate docile stall characteristics, which Tobias fully explored during more than 1,000 stall tests. “It’s a pussycat,” he said. Fowler-type flaps, in three sections, are electrically actuated. Five sections of hydraulically powered spoilers provide lift, drag and roll control, supplementing the ailerons at the outer section of the wings.

The empennage also shares Sovereign+ heritage, with a zero-dihedral, trimmable horizontal stabilizer and anti-float tabs on the elevator, interconnected to the stabilizer. A rudder bias system enables feet-on-the-floor engine-out operation. The rudder is equipped with a single yaw damper.

The flight controls are mechanical, and this (in addition to the adoption of major components from the Sovereign+) helped speed the Latitude toward certification. “The goals of the program were not only to develop this new cabin,” Pierce explained, “but also to do so as quickly as possible. And [to make it] very reliable, using as much proven technology as possible.”

Two compartments, on either side of the fuselage aft of the wings, each house a nicad battery. Four easily operated latches replace Dzus fasteners found on older airframes. The maintenance access space in the tailcone can’t be described as a typical hellhole because the area is clean and extra spacious, which technicians will appreciate.

The large baggage compartment is fitted with the same simple latches as the nose compartment doors and can hold up to 1,000 pounds. A 50-pound-capacity coat rod is installed, too. The door has an integral step, although the 4.5-foot sill height is low enough for most people to lift luggage into the compartment with ease.

On top of the aft fuselage, a pitot-style inlet at the base of the vertical stabilizer helps improve the efficiency of the air-cycle machine.

Flight Deck Features

The cockpit of the Latitude felt familiar to me since I have flown the Intrinzic-equipped Citation X+ and Sovereign+. And as it is in those jets, the cockpit is roomy and uncluttered, with far fewer switches, knobs and controls and a slimmed-down center console than in older Citations. Small touches add to the cockpit’s comfort, such as side pocket areas that are ideal for tablet computers and other portable items, leather-wrapped yokes and console, push-to-talk switches on the sidewalls and in general a modern look and feel.

The Latitude fuselage diameter is 12 inches larger than the 72 inches of the XLS+, Sovereign+ and X+, and thus the Latitude’s interior cabin width expands to 77 inches compared to 66 inches in the other jets. This adds about four inches of cockpit width for each pilot, making more space for the pilot seat armrests as well as the side pockets, which also include USB chargers. Pilot seat travel is three inches longer and the windshields are larger. Because the right-seater usually sits back from the instrument panel, the right outboard touchscreen controller was moved slightly aft to match that typical seating position.

The big benefit of touchscreen controllers is elimination of the FMS control display units that usually take up space in the console. An FMS is still part of the G5000 avionics, but it is buried in the circuit cards and software behind the scenes, and all pilots have to do is push more intuitive touchscreen iconography to make the airplane go where and how they want.

The four GTC 570 touchscreen controllers in the Latitude use infrared technology instead of the capacitive touch we are all familiar with on our smart devices or the resistive touch used for some products, which requires a more hefty push to activate. The infrared touchscreens make it easy for designers to build in features such as not allowing anything to happen when more than one finger pushes on the screen or preventing an electronic button push if the finger misses the target. This version of the G5000 now has full systems synoptics pages. Checklists and performance calculations will be added shortly.

Standard on the Latitude is Garmin’s SafeTaxi airport charts. SurfaceWatch is optional and provides aural and display warnings for maneuvers such as accelerating on a taxiway, crossing an active runway, getting too close to the end of the runway while decelerating after landing and so on. SurfaceWatch will eventually be integrated with ADS-B in. The Latitude is equipped with ADS-B out as well as Sirius XM weather and radio. Datacom features for European Link 2000+ and controller-pilot datalink communications will be an option.

Flight planning is intuitively simple, just a matter of typing in waypoints and destination, plus anticipated arrival procedures, and it’s easy to make changes to a flight plan. Once the destination is in the system, the automatic pressurization system sets the arrival field elevation then automatically schedules cabin altitude and rate of change. At the maximum altitude of 45,000 feet, the 9.66-psi pressure differential produces a cabin altitude of 6,000 feet. Two-zone temperature control is available, and the VIP seated passenger can set cabin temperature; the pilots have control of their comfort using a page on the touchscreen controller. The adjustment is done on a visual gauge, which also shows the desired temperature. I found the adjustment to be precise, with a few degrees either up or down making a perceptible difference in the cockpit environment. Ten air vents, including one behind each pilot, help distribute air in the cockpit. The Latitude is the first Citation equipped with a cabin Hepa filter, which captures small particles.

Typical for large Citations, the Latitude has a hydraulically powered rack-and-pinion nosewheel steering system, which is sensitive. The rudder pedals allow up to 7 degrees of left or right travel, while the handwheel (tiller) in the cockpit moves the nosewheel 81 degrees either side.

Latitude Flying

We took off from Burbank’s Runway 15 with a slight left crosswind, and once I pushed the power levers forward, the Garmin autothrottles took over and smoothly brought the Pratt & Whitney Canada PW306D1 turbofans to maximum power. The engines are the same as those in the Sovereign+ and have a 6,000-hour TBO and 3,000-hour hot-section interval, or can be placed in on-condition service when participating in P&WC’s flight data acquisition and transmission program.

We quickly accelerated through V1 of 99 kcas and rotated at 102 kcas. We were relatively light, carrying just one other crewmember and 5,490 pounds of fuel. With a basic operating weight of 19,076 pounds, the Latitude weighed nearly 6,000 pounds short of the 30,800-pound mtow. Fuel capacity is 11,394 pounds, and typical payload with maximum fuel is 1,040 pounds. Burbank’s weather was normal clear southern California conditions, but slightly cooler at ISA standard, and our balanced field length was just 3,000 feet.

The autothrottles helped keep us shy of 250 ktas below 10,000 feet, although that setting can be adjusted depending on the airspace requirements of a particular country. During the climb to FL430, the autothrottles automatically set power for the Mach 0.64 climb speed and then, when required to level off, transitioned to the target cruise speed of Mach 0.80. Even with a few level-offs, it took only 10 minutes to reach FL270 and at our medium weight we leveled off at FL430 twenty minutes after takeoff. At mtow, the Latitude can climb unrestricted to FL410 in 21 minutes and reach FL430 in 26 minutes. At that altitude and ISA -1, the Latitude settled at Mach 0.76 and 436 ktas, burning about 740 pph per side.

When leveling off, the autothrottles are designed to maintain maximum continuous thrust for about 10 minutes then reset to the high-speed cruise setting. Or I could just tap the autothrottles off before the 10 minutes are up then tap again to go right to the cruise setting. For a longer-range cruise–the AFM recommends Mach 0.74–I could switch the SPD control on the mode controller panel to manual and dial in Mach 0.74 and the autothrottles automatically reset to maintain that speed. At Mach 0.74 and 423 ktas, the fuel flow dropped to just below 700 pph per engine.

We spent a few minutes at FL430 and by this time we had nearly made it to Salinas. The Garmin automatic flight control system, driven by low-maintenance clutchless servos, smoothly kept the Latitude on track. Turning back south, we descended at Mach 0.79 to FL380, where the cabin altitude was 4,500 feet and the true airspeed 445 knots.

At 39,000 feet, the performance charts show 437 ktas burning a total of 1,749 pph at high-speed cruise. At long-range cruise, the speed would drop to 344 ktas and fuel consumption to 1,124 pph. At our weight at high-speed cruise, we would have been able to fly for about five hours, and the total range with NBAA IFR reserves (200-nm alternate) would be nearly 2,400 nm. At long-range cruise, that distance should extend to about 2,800 nm. “[The Latitude] is pretty happy at 38,000 to 43,000 feet,” Tobias said.

The autothrottles maintain the same speed schedule when descending, including the level-off protocol. The G5000 was set to reduce speed to 200 ktas below 3,000 feet within 10 nm of the airport. The autothrottles begin the power reduction during the descent at 12,000 feet to capture 250 ktas transitioning below 10,000 feet. In our case, airspeed reached 250 knots in plenty of time, at 10,800 feet. 

On the way down, Tobias demonstrated the envelope-protection features of the Intrinzic/G5000 avionics. For high-speed protection, the autothrottles pull the power back to maintain speed below the Mach 0.80 Mmo, but they release after a safe flying speed is achieved. On the other end of the speed spectrum, the autothrottles advanced power as we slowed the Latitude in level flight. This is helpful for occasions when pilots might forget to advance the power after leveling off. The envelope protection kicks in even if the autothrottles are not engaged.

For any kind of high-altitude depressurization, above 30,000 feet the autopilot automatically engages the emergency descent mode and brings the Latitude down to 15,000 feet. The new digital pressurization system, with a Honeywell electronic pressurization controller, will output an amber caution message if some aspect of the system is causing a problem. This could include an outflow valve fully closed in flight, for example, allowing the caution to illuminate even before reaching a higher altitude.

We were planning a VFR approach and landing at Camarillo Airport, but the coast was socked in and we didn’t have time to file a new IFR flight plan, so we abandoned that approach and flew back to Burbank for the ILS Runway 8 approach, which I flew by hand to get a better feel for the Latitude’s low-speed handling. Back closer to the ground, the G5000’s synthetic vision display was a welcome sight, clearly highlighting the tall mountains east of Burbank.

The G5000 system’s split-screen capability was also helpful, allowing me to set up the MFD just how I like, with engine instruments and the map on the MFD and the approach plate side-by-side with synthetic vision on the PFD. Full flaps (35 degrees) Vref was 97 ktas, and the Latitude sailed smoothly down to the runway, with the autothrottles automatically pulling power as we crossed the threshold for a firm but satisfying touchdown on the Latitude’s forgiving dual-wheel trailing-beam landing gear. I popped the speed brakes and stepped smartly on the pedals and the Latitude’s anti-skid carbon brakes brought us to a quick stop without any reverse thrust.

Tobias asked if I wanted to taxi back for another takeoff, this time with a V1 cut, and I couldn’t refuse. I got some more practice trying to avoid jerking the nose around while taxiing with the handwheel, then lined up for takeoff on Runway 15. At V1, Tobias pulled the right engine, and I could feel the rudder bias system kick in because when I automatically tried to push the left rudder pedal I found it was already where it needed to be. The Latitude climbed out easily at 2,000 to 2,500 fpm. I circled around to Runway 8 for a single-engine landing at flaps 15 and a Vref of 104 ktas. I came in a little fast this time, but there was plenty of runway, and after another decent touchdown I got on the brakes after deploying the speed brakes then used a little reverse thrust.

 

Fleet Fit

The Latitude occupies its own niche in the Citation lineup, but in my opinion it also competes strongly with both the XLS+ and Sovereign+, although it costs a few million more than the smaller XLS+ and a couple of million less than the Sovereign+. Both the Sovereign+ and Latitude share the same 620-cu-ft cabin volume, but the Latitude’s flat-floor cabin is a powerful bonus that might be attractive enough to offset the Sovereign’s greater range and speed.

“We worked hard on the [Latitude’s cabin] environment,” said technical marketing manager Pierce. The windows are 25 percent larger than those of the XLS+, Sovereign+ and X+ and placed to optimize the passenger’s view. Dual-mode manually operated shades are installed, so passengers can choose between fully dark or opaque settings.

 The seats, designed and built by Textron Aviation, draw on many hours of attention by human-factors engineers working with people sitting in place then trimming foam until the right shape is found. “Then we built the frame,” he explained. The seats fold back fully and lay flat, and they are equipped with armrests that tuck into the upright when not being used. The bottoms of the seats are left open to add to the cabin’s spacious feel.

For passengers, the Heads Up Technologies fiber-optic wireless Clairity cabin-management system controls the environment, entertainment features and lighting. Each seat has its own lighting switches, USB port and a small recess that is ideal for a smartphone, wallet or book. Square cupholder holes can also hold smartphones. Clairity can be controlled using a mobile device app or also from the VIP seat and using a master control in the forward refreshment center. Audio content on mobile devices can be played on the Clairity system’s excellent speaker system.

The typical Latitude cabin layout is nine seats, with a two-place couch forward, then a club seating area, two forward-facing seats and an extra takeoff/landing-approved belted seat in the lavatory opposite the toilet. That seat converts to extra cargo space by folding down, but there is also a closet for hanging storage. Or buyers can opt to eliminate the lavatory seat and make that area into a larger closet. The main cabin seats are toed out by 4 degrees for more comfortable legroom, and both sides of the seats have armrests. “We worked on making sure the floor is as low as possible,” Pierce said, “so shoulders are at the widest part of the cabin. The head and shoulder distance between the fuselage is big, so you don’t feel like you’re against the wall.”

From a handling standpoint, I found that the Latitude flies a lot like the Sovereign+: no fuss and no surprises, excellent performance, intuitive avionics and systems and a super-quiet cockpit. Add to that a roomy and comfortable cabin and plenty of range and payload capability, and the Latitude should prove a popular addition to the Citation line.