CITATION CJ4 SIX REASONS WHY IT’S CESSNA’S RISING STAR. Dave Calderwood finds out why the firm’s best-selling jet for the last two years makes such a compelling case.
THERE’S only so much stretching and tweaking you can do to an aircraft design. Eventually, to make a quantum leap, you have to do something radical. So when Cessna saw Brazil’s Embraer move into CitationJet territory with the Phenom 300, more modern, faster, longer range, more comfortable than the existing CJ3, Cessna knew it had a fight on its hands.
The legendary US firm had some tricks up its sleeve though. The CJ family has several different sizes, and the next up from the CJ3 was the midsize Sovereign. Bigger and rangier, it also had a completely different wing… and so the basis for the CJ3’s successor, the CJ4, was born.
Mate Sovereign wing to stretched CJ3 fuselage, add significant updates, make a thoroughly tidy job of the aircraft and you have: the CJ4, competitive on performance, price and equipment to the Phenom 300.
Both the CJ4 and Phenom 300 are doing pretty well sales-wise, vying for top spot in terms of numbers in 2012 (along with the Challenger 300), so both manufacturers are clearly in touch with the market. With 44 sold in 2012, and 48 in 2011, the CJ4 is Cessna’s star turn.
We flew in the CJ4 at Cessna’s HQ in Wichita, Kansas, to see just what key elements make it truly stand out.
1. THE POWER AND THE PERFORMANCE
This isn’t just the biggest CJ ever, it’s also the best performing. The figures speak for themselves: a max cruise speed of 451kt true at a ceiling of 45,000ft. A maximum Mach speed of 0.77. A sea-level climb rate of 3854 feet per minute. A range of 1920nm at a cruise speed of 425kt true (that’s the brochure figure; in use some have seen fuel burn rates at cruise which would give it 2002nm range). These are astonishing figures for a light jet.
And yet the speed, operating altitude, climb rate and range have not been at the expense of takeoff and landing performance. Small jets need to get in an out of small airfields sometimes, and the CJ series is noted for this ability. The CJ4 continues this tradition.
We had a perfect example of the CJ4’s liveliness of takeoff. Our first flight from Wichita’s Mid-Continent Airport (where Cessna has much of its HQ) was with two pilots up front, and four passengers, all hefty six-footers and carrying photo and video equipment. So we weren’t particularly light.
We lined up on runway 19R, held the CJ4 on the brakes while the latest generation Williams FJ-44 engines spooled up to full power, then released into a ‘Performance Takeoff’. Count to five and that’s how long it took us to get airborne, just as we were passing the first intersection – about 1500ft. The acceleration to the Vr of 93kt had been a real push in the chest and even Cessna’s CJ guru and pilot Brandy Althouse, who’s done this many times before, admitted being impressed by the CJ4’s response. It was a freezing cold Kansas winter’s day but even so…
We were at 17,000ft in four minutes, where we levelled off. Cessna says the CJ4 can get to 45,000ft in just 28 minutes so you can get above the weather and airliners. Again, that’s a brochure figure at standard temperatures and pressures – some have seen a considerably quicker climb to the max operating altitude.
After just over an hour’s flying, we headed back to Wichita. First to drop off the camera and video crew, then to do another takeoff, circuit, touch ‘n go and landing for the snappers. Even with our full load of pax for the first landing, it was over quickly and needed less than the takeoff roll.
One of the beauties of the smaller FJ-44 engines is that you land with the throttle set to idle. If you do need to go-around – or make a touch ‘n go – then they spool up to full power very quickly.
2. SIZE MATTERS
Cessna has added two feet to the length of the cabin for the CJ4 over the CJ3. There’s now a more spacious galley area immediately as you come in through the door, which has also been redesigned. It’s larger, easier to lock and has a very neat set of stairs which just fall into place. The pilots also get a little more room.
Stepping into the main cabin is a surprise. This is a very roomy jet! Yes, you do have to duck your head a little if you’re a six-footer but you hardly notice it. The leg room is excellent and the seats must be among the most comfortable private jet seats in the industry. The section of the fuselage is exactly the same as the CJ3 but Cessna has worked some magic and made it appear bigger. It’s lighter, although the electronically controlled window shades can darken it quickly if you want to nap.
There’s a huge baggage area at the rear of the cabin, which can be accessed in flight. The small bathroom and lavatory actually has sufficient privacy to be usable. The demo aircraft had achieved a balance between a comfortable working environment, with individual side tables, and somewhere to relax after a busy day of meetings. In fact, you could easily hold a small meeting in the cabin… the advantage being that you could genuinely call an end to proceedings with the words, “Gotta fly!”
3. THE WING IS AT THE HEART OF THE STORY
What makes the CJ4 such a good performer at high speed and long range, as well as short takeoff and landing, is the new wing.
Actually, it’s not entirely new because something very similar is fitted to the next-size-up aircraft, the Citation Sovereign (itself in the process of being upgraded for launch later this year). Now, if you’re as geeky as me when it comes to technical stuff on aeroplanes, you’ll probably do what I did which was to admire the wing from every angle.
First thing you notice, particularly when the CJ4 is parked next to a CJ3, is that the wing is swept. On the earlier CJs it’s more or less straight out. The sweep is 12.5° which is pretty modest but it also continually changes shape along the length of its leading edge. The trailing edge is dead straight which, according to Cessna engineers, is how they retain the good low speed behaviour.
Look at the wing end on and it’s a thing of beauty. Slim and clean to aid laminar flow to reduce drag, but with some major changes over the CJ3.
The overall wingspan is less by 2ft 6in but the chord is deeper, overall increasing wing area by 36ft2, again helpful at low and high speed. Bigger wing also means more fuel – the CJ4 can hold 5828lb of fuel, an increase of 1118lb over the CJ3 – and thus more range and flexibility.
Despite its clean appearance, the CJ4’s wing is more complicated but for good reason. The CJ4 not only has wing spoilers top and bottom on each side acting as a speed brake (like the CJ3) but they can be deployed at any speed and to any degree (unlike the CJ3’s which are either full on or full off). According to Brandy, this makes it much easier to comply with ATC instructions on speed and flight levels particularly when stepping down through busy airspace.
The CJ4 has another trick up its sleeve too. The same lever which deploys the speed brakes can be pulled back another notch on landing and three ground spoilers each side pop up from the top of the wing. These immediately kill lift and press the aircraft onto the runway meaning the pilot can brake harder sooner, should it be needed. The effect is to reduce landing roll.
All in all, this new wing is at the heart of the CJ4.
4. AVIONICS ARE INTRINZIC
‘Intrinzic’ is the name Cessna is giving to its avionics installations these days, irrespective of the original supplier.
This was a tad confusing because I first came across an Intrinzic flightdeck in Cessna’s top-of-the-range single-engine piston aircraft, the new TTx, which features a Garmin’s G2000 suite. However, in the CJ4, the avionics are Rockwell Collins Pro Line 21 with an Integrated Flight Information System.
Whatever the name, the cockpit is bang up to date. Four 8in x 10in screens march across the panel, two Primary Flight Displays and two Multi Function Displays. Even though the CJ4 is rated as single pilot, most operators will have two pilots so both need live info.
The CJ4 is a true paperless cockpit, with electronic charts, approach plates, and airport diagrams appearing on the MFDs. Graphical weather can be overlaid, and MultiScan Weather Radar can be added to give actual, live awareness of bad weather.
The cockpit has been redesigned with single pilot use in mind, so things like toggle switches whose position – up or down – can be confusing at have been eliminated and replaced with simple press on or off buttons that light up when on.
Autopilot controls have been moved up to the top of the panel so you can make changes while keeping your eyes around the windscreen level rather than delving down. The autopilot also has an Emergency Descent Mode so if cabin pressure is lost above 30,000ft, the aircraft will automatically descend to 15,000ft where the level of oxygen in the atmosphere should revive a woozy pilot.
And there’s a new Engine Indicating and Crew Alerting System (EICAS) which sends plain English messages to the PFD in the event of any malfunction or unusual condition. If it’s serious, then there’s also a verbal warning.
5. CABIN AND CLIMATE
Of course, all that technology up front is great for pilots and reassuring for passengers, but what the customers will really appreciate is the Cabin Management System.
Like the avionics it is a Rockwell Collins system, called Venue HD. Venue manages not just the cabin climate control system (air con to you and me) with two separate zones for the pilots and passengers, but also the ‘infotainment’ system.
There are iPad size monitors around the cabin, and each seat has inputs for mobile devices so passengers can play CDs, Blu-ray discs, DVDs and games, listen to satellite radio channels, or even connect games consoles like PlayStation 3 and Xbox 360. Of course, you can plug in a laptop and get on with some work.
Cabin pressure is digitally managed too and Cessna says the CJ4 keeps sea level pressure up to 27,000ft. All the lights inside the CJ4 cabin are LEDs, using less power and lasting longer than bulbs.
6. EASE OF USE
At the heart of the CitationJet CJ series is ‘ease of use’, says Cessna. The CJ4 is the biggest jet Cessna makes which can be flown single pilot, so the onus is on making it easy to fly.
It starts with the handling of the aircraft, with easy, docile manners at all speeds, particularly during landing and takeoff. Add in details like the speed brakes which can help you quickly and easily fine-tune the speed by 20-40kt if requested by ATC, the ground spoilers which improve landing roll and braking, particularly on a soaking wet runway, and the slightly narrower landing gear spacing which helps the aircraft manoeuvre more nimbly when taxiing.
There’s the design of the cockpit, not just from an aesthetic point of view, but having everything in a logical easy to reach place. Autopilot between the displays and the windscreen. Input pad for the Flight Management System in the centre just under the MFDs. Throttles, flaps, and spoilers on the same console and operating in the same sense. Undercarriage lever bang in the centre between the MFDs so there’s no confusion.
The avionics are all about improving situational awareness and managing pilot workload. There’s no doubt being able to call up charts and plates onto displays is much better than rooting through old and heavy paper manuals.
Even the redesigned cockpit windshields with always-on heated glass reduce workload, replacing the old system of hot engine bleed air onto plastic windscreens. They look much better too – sleeker and more graceful.
The latest generation FADEC-equipped Williams FJ44-4A engines are among the quietest and greenest available, and feature Cessna’s GreenTrak system. This calculates Direct Operating Costs, fuel burn, and carbon emissions and thus fits right into Europe’s (much disputed!) Emissions Trading System.
CONCLUSION: SIX OF THE BEST
Perhaps the single most amazing thing about the Citation CJ4 is just how complete the upgrade is from the old CJ3. Should we expect anything less from Cessna with its vast experience in building light and midsize jets?
No, but business aviation is an intensely competitive arena with much to contend with in terms of regulation, cost, customer expectation and safety. The CJ4 is bang up to date on all fronts, and it’s easy to see why its star is rising.
|CESSNA CITATION CJ4|
|Max Cruise 451ktas|
|MMO Mach 0.77|
|Max Range 1920nm|
|Takeoff Distance 3190ft|
|Landing Distance 2740ft|
|Maximum Climb 3854fpm|
|Engines 2 x Williams International
FJ44-4A, producing 3621lb of thrust each
|Engine TBO: 5000hr|
|Max Fuel Capacity 5828lb|
|Useful Load 6880lb|
|Maximum Payload 2150lb|
|Full Fuel Payload 1052lb|
|Baggage Capacity 1040lb/77ft3|
|Length 53ft 4in|
|Height 15ft 4in|
|Wingspan 50ft 10in|
|Wing Area 330ft2|
|Length 17ft 4in|
|Max Seating 9|
|Single Pilot Certified Yes|