Before the economic meltdown in 2008, very light jets were all the rage. Manufacturers such as Eclipse were going to revolutionise air travel with air taxis, and their designs would also be frugal enough for owner-operators to enjoy the speed and reliability of jet propulsion.
After the crash, long-range, large-cabin offerings soared above the fray, while VLJ orders suffered significant hits – and the light jet market seems to have remained stuck on the tarmac.
New offerings were highlighted by Embraer’s successful Phenom 300 and Pilatus’s in-development PC-24. But Cessna, which arguably can be credited with founding the light jet segment, has not rested on its laurels during this time of stagnation. In 2006, the company launched the Citation CJ4. Based on the CJ3, the bigger, faster and more capable model was first flown in 2008, with deliveries starting two years later.
Having made its flight debut in April 2003, the CJ3 was itself a stretched and improved derivative of the CJ2. After a 10-year production run and the delivery of over 400 aircraft, Cessna decided that the CJ3 needed an update.
Upgrading an existing business jet is a common tactic used to keep a product fresh and relevant in the marketplace. The scope of modifications can vary greatly: from a new paint job and interior to new engines, avionics and aerodynamic refinements.
Announced in 2014, Cessna’s Citation CJ3+ promised only an upgraded avionics suite to differentiate it from its predecessor. In general, a “new and improved” aircraft should do at least one of the following: go faster, go further, carry more, be more economical to operate, or more environmentally friendly, in terms of noise/emissions.
I am by no means a “Techie”, and was a bit leery when Cessna offered an evaluation flight in its newest CJ. I had already flown the then newly certificated CJ3 in Wichita, Kansas early in 2005. At the time, I was impressed by its docile handling and then state- of-the-art Rockwell Collins Pro Line avionics suite.
From propulsion and aerodynamic standpoints, the CJ3+ is essentially identical to the CJ3. It isn’t faster, doesn’t carry more, nor is it more economical or environmentally friendly. Yes, new paint schemes are available and the already-comfortable cabin features worthy improvements, but I wondered what else could justify the redo of an already successful aircraft?
While pilot preferences for avionics packages have not devolved into iOS versus Android camps, Garmin’s arrival and ascendency has brought choice to the marketplace. A good number of pilots have grown up using Garmin avionics, finding the company’s methodology to be “intuitive”. But having spent two decades flying transport-category aircraft, I would be more inclined to say a Collins or Honeywell flight management system (FMS) was the more “intuitive”. No matter the background or reason, pilots do have preferences.
The CJ3+’s bigger sibling, the CJ4, is equipped with a Pro Line 21 system, which I found to be similar to the avionics in a number of the Boeings I have flown. Like other CJs, the 3+ is single-pilot certificated, and a good number of buyers will be owner-operators moving up from smaller Garmin-equipped aircraft. So putting a highly capable G3000 avionics suite into the aircraft has leveraged two sets of loyalties: one to Cessna, and the other to Garmin.
My preview flight was conducted from Textron Aviation’s Cessna facility, located at Wichita’s Dwight D Eisenhower International airport (KICT). I followed Textron Aviation senior pilot John Reimer as he accomplished the pre-flight walk-around inspection.
The overall fit and finish of the CJ3+’s surfaces were outstanding – especially those of its relatively high aspect ratio (9.52) straight wing. The bleed air-heated leading edge is polished aluminium, and the smooth surface aft of the join line essential for maintaining laminar flow. Unlike the CJ4, this model does not have heated windscreens, rather using engine bleed air to defrost them. The same bleed air aids in clearing rain, along with a rarely used mechanically actuated rain diverter flap for heavy precipitation.
Rounding the aircraft’s tail, Reimer opened the tail cone baggage compartment door. At chest-level, this facilitated easy access to the long, 1.42m3 (50.5ft3) space: skis up to 2.15m (7ft) in length can be carried.
As I have come to expect for a Cessna, the inspection was straightforward, with all required inspection panels accessible from ground level. Entry into the aircraft was via the manually operated entry door, which has integral steps and features both active and passive seals.
Prior to entering the heavily revised flightdeck, I spent a few minutes in the CJ3+’s cabin, which shares a common fuselage tube with other CJs. Over the 12.7cm (5in) dropped aisle there is 1.45m of headroom, and the cabin is 1.47m at its widest. These dimensions are on a par with other light jets, but are slightly smaller than those offered by the Phenom 300.
Two features served to make the cabin – configured with four club seats forward and two seats aft – more spacious. To free up aisle space, the outboard armrest stows in a recessed portion of the reclinable seat-back. Taller occupants may find headroom compromised by the cabin’s sidewall, so each pedestal seat can slide out by approximately 8cm into the aisle, creating more usable space. At the aft end of the cabin is a commode area, which has a belted lavatory and coat rack. While the CJ3+’s large cabin windows provide a good view, some passengers may prefer looking at more pedestrian entertainment. Broadband connectivity, a wireless network and media server are optional extras. No displays are installed in the cabin, and passengers use their own screens to view content.
A folding curtain separates the flightdeck from the comfortable cabin. Settling into the left seat, I scanned the flightdeck. I had flown the G3000-equipped M2 in 2013, and unsurprisingly I found the CJ3+’s forward panel was nearly identical to it, as all CJs share a common type rating. The panel is dominated by three 15.2in GDU1400W control display units. For our flight, they were configured with primary flight displays (PFDs) outboard and a single, centre multifunction display (MFD). Two GTC570 touchscreen controllers are placed forward of the throttle quadrant, below the MFD. The controllers have a 5.7in screen and are the primary interface for the G3000 system. Dual GPS receivers are standard, along with a transponder that has automatic dependent surveillance-broadcast as well as European Mode S capabilities. Rounding out the notable standard avionics are the GTS 8000 TCAS II terrain collision avoidance system and a Class B terrain avoidance warning system.
Our demonstrator aircraft – N484CJ – also had several welcome optional systems installed. These included synthetic vision technology (SVT), SiriusXM satellite radio and weather radar, as well as Garmin’s Surface Watch.
The full-authority digital engine control-equipped Williams FJ44-3A turbofans were started on aircraft battery power alone. Once both generators were online, Reimer turned on the vapour cycle air conditioner to cool the flightdeck. He guided me through the post-start flows, which were logical and easily accomplished. During the taxi to runway 19L I monitored our position on the MFD’s map; ownership position is also available on the JeppView’s airfield diagram chart.
During the taxi, Reimer explained how Surface Watch differs from Honeywell’s runway advisory and awareness system. RAAS provides a constant stream of dialogue, notifying the crew as they approach each and every runway. I had previously seen this system first-hand in a Hawker 4000 preview flight out of San Diego International airport, and was in general pleased with its performance. Surface Watch, on the other hand, compares current position with the programmed runway. Only if take-off is attempted from other than the planned runway will a warning be issued.
The flaps had been positioned to 15º prior to taking the runway, and I advanced the thrust levers to the take-off detent when cleared to do so. The engines stabilised at 102% N1, as the CJ3+ briskly accelerated down the runway. Reimer called “V1” at 99KIAS, followed shortly by “Rotate” at 101KIAS. The 5,850kg (12,900lb) Citation – with three occupants on board and carrying 1,750kg of fuel – leapt off the ground. Once airborne, I retracted the landing gear with flap retraction at 400ft above ground level.
The TLs were set in the CLB (climb) detent after the CJ3+ was clean. I followed the flight director’s V-Bar guidance cue to establish a 225KIAS climb. Air traffic control provided vectors to our working area west of KICT. Passing 10,000ft above mean sea level I engaged the autopilot and marvelled at the inherent capabilities of the G3000 flight deck. Opposing TCAS targets were displayed on the PFD’s full-screen display. While Kansas is essentially flat, the SVT’s ability to display terrain and obstacles could come in handy at lower altitudes over more rugged terrain. Climbing through 27,000ft, Mach 0.56 was held, until we leveled off at the CJ3+’s ceiling of 45,000ft (FL450).
Conditions that day during the climb were much hotter than normal, with temperatures of up to ISA +18ºC observed. Time to altitude from brake was less than 26min, and only 272kg of fuel was used. These observed figures compared well with Cessna’s standard day figures of 23min and 238kg, respectively.
Five minutes after levelling at FL450 (ISA -4ºC), the TLs were retarded to the CRU (cruise) detent. After 10min, the Citation had reached its maximum cruise speed of M0.729, indicating 193kt. Total fuel flow was 800PPH, with a corresponding true airspeed of 412kt (357km/h). The observed top end was 27kt faster than book values, but total fuel flow was also 80PPH greater. While not as fast as the swept wing CJ4 or Phenom 300, the CJ3+’s rapid climb and respectable high-speed cruise capabilities would make short work of most operator’s normal routes.
I passed aircraft control to Reimer, and left the flightdeck to sample the cabin environment. Deck angle at high-speed cruise was level as I walked to the aft end of the cabin. The ambient noise level was lowest at the first row of seats, and increased as the pod-mounted engines were approached. In general, the cabin was quite quiet, allowing conversation at normal voice levels throughout.
On returning to the flightdeck, I noted the cabin altitude was 7,900ft while still level at FL450. The CJ3+’s 0.61bar pressurisation system provides a sea-level cabin up to almost 23,600ft, and its operation is entirely automatic, based on inputs to the FMS. Once seated, I retarded the TLs to set a total fuel flow of 700PPH, for a long-range cruise point. The aircraft slowed to M0.69 (183KIAS), with a resulting true airspeed of 391kt. While still at cruise altitude, Reimer explained the CJ3+’s emergency descent mode. Should cabin altitude exceed 14,500ft with the aircraft above 30,000ft, the autopilot will turn the CJ3+ 90º left and initiate a descent to 15,000ft MSL.
Cleared by air traffic control to initiate a descent to medium altitude, I started a shallow descent and made several 45º and 60º angle steep turns at 190KIAS. There was no buffet and yoke force pergwas linear. After rolling out I lowered the Citation’s nose to accelerate and maintain maximum operating speed.
Once stable at M0.737, I made a series of sharp control inputs in each control axis, with yaw damper on, with resultant aircraft response well damped. With the YD off, the Dutch Roll response to a rudder input was snaky (more yaw than roll), and lightly damped. Turning the YD on quickly damped out the oscillations.
After retarding the TLs to idle, I lowered the nose and initiated a simulated emergency descent. Speed brake extension dropped the nose slightly, and a few kg of aft yoke pressure was needed to maintain the desired pitch attitude. During the descent I observed vertical velocities in excess of 6,000ft/min. Reimer said he has seen a rate as high as 8,000ft/min: either descent rate is more than sufficient to rapidly get the aircraft down to a safer altitude.
Following vectors to the east for our descent, we levelled off at 9,500ft MSL and cancelled instrument flight rules. To slow the CJ3+ for a clean configuration stall, I set idle power and performed some steep turns at 60º. Pitch and roll forces were well harmonised. With the YD engaged, they could be accomplished with both feet on the floor. Once slowed, I levelled the wings and the aircraft slowed at 1kt/s. At 103KIAS in a 10º nose-up attitude the stick shaker activated.
Ignoring the shaker, I slowly pulled full aft on the yoke. The CJ3+ settled into a 7º nose-up descent at 97KIAS. During the 1,600ft/min descent, the wings were level and rock-steady. Recovery from the stalled flight condition was made by relaxing yoke pressure and advancing the TLs to the TO detent. Impressed with the CJ3+’s slow-speed handling qualities, we asked for vectors for a visual approach to RWY19L.
My experience in the G3000-equipped M2 and prior flights in the CJ3 and CJ4 convinced me that I would learn more about the CJ3+ by hand flying it in the pattern than doing coupled instrument approaches. The first approach was at flaps 35 with an approach speed (Vapp) of 111KIAS and a reference speed (Vref) of 103KIAS. Reimer challenged me to do a short-field landing and stop by the first taxiway (M2); about 570m from the approach end.
The CJ3+ does not have thrust reversers, but it does have anti-skid brakes and a feature near and dear to the heart of Hawker pilots: a lift dump flap position. I retarded the TLs to idle passing 30ft and we touched down several hundred meters past the threshold. Immediately, Reimer set the flaps to 55º: their lift dump position. As they extended, the speed brakes automatically extended to spoil lift and make the wheel brakes more effective. The CJ3+ slowed rapidly and we easily stopped on runway centreline abeam taxiway M2, 570m from the threshold.
Reimer set the flaps to 15º and reset the pitch trim for our next take-off, and I set TO thrust for a routine take-off. Once airborne with the gear retracted, however, Reimer pulled the left TL to idle to simulate an engine failure. I first noted the thrust asymmetry as the aircraft yawed left. Any doubt I had about which engine had failed was erased as the CJ3+’s rudder bias system moved the rudder pedals, applying right rudder to slow the yaw rate. At TO power and 120KIAS, less than 30kg of right pedal pressure was needed to maintain coordinated flight. I flew the visual circuit on one engine. Rudder trim was centered on final, for an uneventful one-engine inoperative approach and touch-and-go landing. Reimer again set the flaps to 15º and both engines were used for the take-off. The final circuit was to another short-field landing, with wheel brakes quickly slowing the CJ3+ for a turn-off on taxiway M2.
When buying a business jet there is never only one correct answer. The light jet segment is populated by a number of highly capable aircraft. Cessna has the most offerings, with its M2, CJ3+ and CJ4 models. During my preview flight I found the CJ3+ performed well at slow speeds and during a simulated engine failure event. The manual flight controls were well harmonised, making the CJ3+ a joy to hand fly.
While slower than the competition, at altitude the cabin was quiet and it is doubtful that passengers would object to the few extra minutes needed to reach their destination. The addition of a G3000 avionics suite to the already successful CJ3 makes the purchase of a CJ3+ a comfortable proposition for those pilots in the Garmin camp.
Citations are touted as being a “sure thing,” and with the CJ3+, Cessna will no doubt further burnish that reputation.
Source: Flight International