Citation CJ4 Gen2

FLIGHT REVIEW

Ten years since the first Cessna Citation CJ4 rolled off the production line, Textron Aviation has unveiled an upgrade to the venerable jet – the CJ4 Gen2. While the performance specifications of the airplane are unchanged, the company incorporated substantial improvements surrounding the cabin experience. I met up with the Textron Aviation team in Santa Fe, New Mexico (SAF), to fly one of the first CJ4 Gen2 aircraft. With flight time in all of the Citation Jet 525 series models, it was a nice opportunity to fly the largest in the line, especially over a scenic area of our country. 

Citation CJ4

While the CJ4 shares many of the same characteristics as the other 525 models, such as the diameter of the fuselage, there are some distinctive differences. The CJ4 was developed just after the Citation Mustang, and you can see some of the same design tenets in the jet, including the cabin door design and more ergonomic flight deck.

The CJ4 is 20 inches longer than the CJ3, the next largest jet in the 525 series. With a 12.5-degree sweep on the 50-foot 10-inch wings, along with 3,621 pounds of thrust generated by each of the Williams International FJ44-4A engines, the jet obtains a high-speed cruise (HSC) of 451 knots with a maximum speed of 305 KIAS/0.77 Mach. One of the many strong selling points of the CJ4 is the range. With one pilot, four passengers and full fuel, the jet can fly a maximum NBAA IFR range of 1,926 nm. Pull the throttles back slightly and you can fly slightly further. Even trading fuel for passengers will still yield a range of 1,700 nm with eight passengers – quite impressive.

The CJ4 Gen2 rolls off the production line with virtually all avionics equipment as standard. The one I flew was no exception with all of the options including CPLDC and the Collins RTA-4112 multi-scan weather radar. The RTA-4112 offers sophisticated weather and turbulence detection with an optimized view regardless of altitude or range. Coupled with long-range NEXRAD, also standard, it provides a near complete view of weather. Among the included equipment is TCAS II, which is an option on other jets. Even fully equipped, along with an interior with all of the options, this CJ4 has a full fuel payload of 1,122 pounds.

Gen2 Upgrade

The CJ4 features a much larger cabin door than other 525 jets, and as mentioned, is similar in design to the Citation Mustang entry. It utilizes passive door seals which is just one of the system simplifications that reduces maintenance. The Gen2 also features a much-improved entry stair design. Not only are the stairs lighted, but also
feature a sturdy handrail, an additional step for easier entry, and a projected lower step floodlight that can display a design of your choice. The new entry sets the tone for the interior upgrades.

Textron Aviation offers several unique materials and finishes with the Gen2, which you immediately notice upon entering the jet. The cabinetry is impressive and has an optional AC outlet with enough power to accommodate your own coffee maker or standard coffee warming tank. And the designers didn’t forget about the pilots. Pilot storage cabinets have been redesigned for easier access from the seats.

In addition to space for a coffee maker, the new galley also has a slide-out countertop to make preparation easier. The surface can be upgraded to granite from a laminate, with a small weight penalty. Owners can also choose between cabinets or side-facing seat combinations, accommodating up to two passengers, installed opposite the entry door.

When you look aft into the cabin, one of the first features you notice is the improved lighting that literally bathes the interior in light. The seats are also upgraded and very comfortable. This particular CJ4 features an interior soft goods upgrade called the Premier Collection Package, which includes detailed seat stitching and an accented overhead console. This package, at $175,000, is a cost-effective method of combining a number of cabin upgrades.

As you venture aft, the standard externally-serviced lavatory has been improved in the Gen2, including the implementation of two Lee Aerospace CoolView skylights. While only 4 inches in diameter, they do let in additional ambient light above the externally serviced toilet while blocking 99 percent of the UV. Along with the Premier Collection Package, the optional sink with running water is installed as well.

Textron Aviation implemented a software-based cabin management system (CMS) that can control the window shades, dimmable LED lighting, Sirius/XM audio radio, and even the cabin temperature. For those passengers that would like to stream content, there is an onboard 180GB media server. With everyone carrying a smart device and technology rapidly changing, the CMS can adapt easily to advancements without hindering operators with cabin display hardware that quickly become obsolete. Each seat also has access to USB power ports, with a single 115VAC/USB-A/USB-C outlet on each cabin sidewall as well.

Preflight

One of the great features I’ve enjoyed with the Citations is the flexible baggage loading. The nose baggage, accessible by two doors, provides a flexible loading configuration for the flight crew. I’ve found it especially helpful when loading walkers, folding wheelchairs, or even extra garment bags. Within the nose compartment are also several sight and pressure gauges, easily accessible during the preflight. The aft baggage in the CJ4 is even larger than the CJ3 with a maximum load of 600 pounds. When you have a maximum capacity of 10 people, you can never have enough luggage space!

Single-point fueling is standard, and while other jets offer digital fuel panels at the port, one advantage of the CJ4 is no battery power is necessary to manage the fueling at a maximum flow rate of 120 gpm. 

The CJ4 sports speed brake panels that offer variable deployment rather than binary operation on other 525 models. The variable deployment is very effective and results in a much smoother flight when deployed. On landing, additional spoiler panels further reduce the lift.

An additional difference with the CJ4 from other Citations is the incorporation of a closed-center hydraulic system for gear, speed brakes/lift dump and flaps. Rather than pressure increasing upon activation of a particular system (open-center) the CJ4 hydraulics are constantly held at 3,000 PSI. 

The flight deck of the CJ4 is clean and well designed with excellent legroom. All of the controls and systems are within easy reach of either pilot, making single or crew operation seamless. One example is the landing gear control, intelligently located between the pilots on the panel – no more trying to reach from the opposite side. Other control functions and panels are also in easy view of the pilots. The lower tilt panels make it much easier to access controls of the dual Rockwell Collins Pro Line 21 CDU panels. The version of Pro Line 21 in the CJ4 features two MFD panels. On this aircraft it was equipped with dual FMS, installed on most of the CJ4s. An additional feature is extensive embedded electronic checklists that facilitate operation. The only way to make them better would be to manage them through buttons on the control yokes.

Time to Fly 

At 14,866 pounds, with three of us aboard, we were under the maximum takeoff weight of 17,110 pounds. Textron Aviation demonstration pilot David Bodlak guided me through the extensive and pilot-friendly electronic checklists. Starting the two Williams International FJ44-4As is simple, and after a few checks, we were ready to taxi. At Santa Fe’s (KSAF) elevation of 6,348 feet and 10-degree Celsius, our takeoff distance was less than 3,400 feet. Acceleration was quick. With a V₁ of 89 KIAS and V_r of 96, I was lifting off of Runway 20 on the ZIASE4 departure. 

The handling qualities of the CJ4 are enjoyable as I comfortably hand flew the jet up to FL400, with an initial climb speed of 240 KIAS. We encountered some turbulence on the way up, which was inconsequential to our flight.

Once we reached FL400, the CJ4 accelerated quickly to cruise flight with a cabin altitude of 6,700 feet and a pressure differential of 8.8 PSID. The CJ4 has a V_mo/M_mo of 305 KIAS/0.77 Mach at high altitude, and we were flying at 436 KTAS/0.74 Mach burning 600 pounds per hour on each engine (this with an outside temperature seven degrees above ISA!).

As pilots we have the best seat in the house, and a excellent feature of the Citations are the large cockpit windows. The side cockpit windows and windshields on the CJ4 feature electric heat that effectively keep them clear throughout flight and enhance the warmth of the cockpit. Their design also virtually eliminates fogging that can occur when landing at airports with high humidity. The cockpit sound level I measured was low, measuring 78-79 dB in cruise.

After flying around New Mexico, it was time to return to base. The Collins Pro Line 21 FMS is easy to program with two Console Display Units (CDU) to enter data, which offers great flexibility especially in crew environments. After loading the VNAV descent and reducing power, I started a descent at 230 KIAS/420 KTAS (close to max speed at FL400) with a ground speed of 517 knots. With a strong tailwind and altitude to lose, it was a great opportunity to work with the speed brakes. The CJ4’s variable speed brakes allow the pilot to progressively extend them with a very smooth operating lever on the center console. The first 10 percent offers a very slight but smooth increase in descent rate. Progressing past 10 percent to 50 percent is still relatively free of vibration, then extending them to 100 percent really shows off their full potential. At 200 knots both gear and approach flaps can be deployed.

We programmed the FMS for the RNAV 20 approach outside of POAKE intersection. Our landing weight was 13,500 pounds with only 3,700 feet required for landing at a V_ref of 104 and V_app of 111. I wanted to hand fly the approach single-engine with a missed, then vector back for another approach to landing, so I limited my flap extension to just Approach. As turbine pilots know, single-engine approaches are relatively easy. It is the missed ones that require specific attention due to the asymmetric thrust. At the DA of 6,800 MSL, I initiated the single-engine missed. As expected, with an asymmetric thrust of over 3,600 pounds, it took substantial rudder pressure to keep the aircraft on the runway heading with the automatic rudder bias doing most of the work. The quick acceleration of the CJ4, even on one engine at high altitude, made the SE climb easy. Quickly at missed approach altitude, it was time to vector back for an approach and landing.

All of the 525 series Citations are easy to land smoothly (making the pilot look good to their passengers). The CJ4 brakes are incredibly smooth and effective, with the same nice feel as the other jets in the 525 series.

When considering a new aircraft, potential jet operators typically consider three options in this class of airplane: Citation CJ4, Embraer Phenom 300E and Pilatus PC-24. The CJ4 and Phenom 300E offer virtually identical top speeds. The PC-24 is slower by about 20 knots. Most people buy jets to go fast, so long-range cruise in the CJ4 at substantially slower speeds is only useful for specific flights. What most people want to know is, “What is the maximum payload with full fuel for the longest possible flight?” In the CJ4 I flew, you could carry slightly over 1,100 pounds. A Phenom 300E would be close to that amount, and the Pilatus PC-24 would be 900 pounds. 

With proven performance, an estimated hourly operating cost of $1,040 (plus fuel), and now upgraded interior, the Cessna Citation CJ4 Gen2 is sure to satisfy the needs of many operators. And thanks to a wide network of maintenance facilities, both Textron Aviation-owned and independent MROs, support is never far away for owners – an important consideration when selecting an aircraft.