As the fight for the single-engine turbo-prop market heats up, Swiss manufacturer Pilatus has launched its latest weapon at the competition. John Absolon leapt at the chance to evaluate the PC-12 NG for Australian Flying.
As a private non-IFR pilot have you ever thought about owning a single-engined turbine aircraft if you ever had the chance? How many times have you looked at those classic lines of a turbine nose cowl on a Caravan, Kodiak, TBM, Meridian or even the utilitarian look of a Porter, and longed for one of these machines to be your own?
Well, one businessman private pilot in Australia has done just that. Simon Hackett recently took delivery of a new PC-12 NG at Pilatus in Stans, Switzerland and flew it back to Adelaide after having sold his internet company, Internode, early in 2012.
Simon’s previous aircraft wasn’t any old slouch either: a four-seat Cirrus SR22 GTS turbo. However, with the number of family members, it always meant someone had to stay behind or travel by an alternative method. The PC-12 NG offers eight seats in luxury air-conditioned and pressurised comfort.
Even though he was accustomed to an EFIS-equipped aircraft with the Cirrus’ Perspective system, to adequately handle the step up to the PC-12 NG, Simon had been doing his type training with Peter Tippett from Pilatus Aircraft in Australia before they ferried the PC-12 NG together from Switzerland.
As an accomplished glider pilot and private pilot, Simon has had little difficulty in transitioning onto the PC-12; not saying that the learning curve wasn’t somewhat steep at times, but he has certainly been able to master the aircraft and now it’s only the IFR training to complete to fully utilize the capabilities that the PC-12 can deliver.
Being able to operate the PC-12 under IFR will then deliver all the benefits that this type can offer: efficient altitude cruise and being able to get into places when the weather isn’t exactly pleasant or VFR. The PC-12 is equipped with the latest in EFIS technology from Honeywell and is displayed in the most up-to-date way on four LCD screens.
Simon began his transition with an intensive week-long ground course on the systems with Peter at Pilatus in Adelaide before setting foot in a PC-12.
The PC-12 has undergone many changes in its configuration since it first appeared in 1991 and then being certified in 1994; the latest PC-12 NG version was unveiled in 2007.
The main difference with the NG (Next Generation) model was the inclusion of the Honeywell APEX EFIS system that allows cursor control of displays and data entry into the Flight Management System. The NG model also included a new version of the venerable PT6 turbo-prop that now delivers increased climb and cruise performance.
Australia has had a long history with Pilatus, for not only were there a number of Pilatus gliders (the Pilatus B4 or known as the PC-11 in the Pilatus system) flown in Australia, but also the Australian Army operated the PC6 Porter from the late ‘60s and the Royal Flying Doctor Service (RFDS) was the launch customer for the PC-12. In fact, the world’s oldest production PC-12 is still flying in Australia.
The RFDS was attracted to the PC-12 by its rugged design, capability to operate from short unprepared strips with a large cabin and easy access through two cabin doors. The aft door needed no modification–unlike the Beech King Air–to allow the loading of stretcher patients.
Australia has embraced the design concepts of Pilatus aircraft particularly with the high quality of typical Swiss workmanship and their attention to designing an aircraft for what the operator really wants, that is, one that performs the job required and is not going to be a burden maintenance-wise.
The PC-12 has undergone many changes through its life so far. This latest variant, the PC-12/47E, incorporates some upgrades to the PT6 turbo-prop and retains the 1200 horsepower rating, aerodynamic improvements and the standard fitment of the Honeywell APEX EFIS. The main benefits of the upgrade to the PT6 are realised when cruising at higher altitude.
The designation ‘47E’ refers to the upgrading to 4740 kg take off weight and E for the improved Honeywell avionics. The plane is known to the market simply as, the PC-12 NG.
Both the cabin and flight deck layouts benefit from the ideas of the BMW Design Studio and their ideas for both styling and ergonomics. These benefits shine in the excellent flight deck layout and clever use of space in the cabin; the fittings not only look stylish but satisfy the latest crashworthy certification standards.
The aerodynamic improvements include the redesign of the winglets that are now angled up and outward more to slightly increase wingspan and aspect ratio as well as being slightly longer to reduce vortices and re-engineering of the ailerons and the incorporation of balance tabs. These improvements together decrease the overall drag and improve handling.
The Pratt and Whitney PT6A-67P turbo-prop engine is flat rated to 1200 HP in this installation. The higher power available is due to a new hot section blade design that allows hotter turbine temperatures.
All these improvements give an extra 20 plus knots in cruise performance topping out at 280 KTAS compared to the previous model of 256 KTAS.
Other systems upgrades in the PC-12 NG include the incorporation of digitally-controlled cabin pressure and environmental control systems. Improvements to the electrical system have also been made to adequately handle the new avionics.
The cabin is pressurised to 5.75 PSI differential, which gives a cabin altitude of 10,000 feet when cruising at FL300. It is also capable of holding a sea-level cabin altitude up to a cruise altitude of 13,000 feet. This is the sort of capability that the RFDS looks for in being able to transport patients with medical problems that could be exasperated by altitude.
The electrical system includes two engine-driven generators, two batteries and is fully automated. The electrical system control switches are situated on the overhead panel.
A separate back-up battery is used to power the integrated Emergency Power System (EPS) bus, including a fully-digital Electronic Standby Instrument System (ESIS).
Walking around the PC-12, you can see the PC-12 NG is quite a large aircraft for a single turbo-prop. The size is disguised when seated in the flight-deck; it feels like a big single as both wingtips are clearly visible through the flight deck windows, and it can be easily flown by a low-time pilot, after a bit of training of course.
The aircraft stands on a sturdy tricycle landing gear with the main gear being of the trailing link design. This gives excellent handling on those unprepared strips while the wide track aids both stable ground handling and excellent directional stability.
This track doesn’t restrict the turning circle of the PC-12 as ably demonstrated to me during our evaluation flight. We were able to turn the aircraft through 180 degrees whilst virtually pivoting on one wheel. The turn was easily carried out within the width of the Adelaide taxiway.
Apart from the wide rear door, the cabin is normally accessed via the forward door that incorporates air stairs that fold out from the inside face of the door. The rear door has no stairs attached.
The cabin is fitted with six seats; the forward four in a club seating arrangement while the aft-most two face forward. The aft right seat has enormous legroom as the aft left seat is located slightly more forward to allow access from the ground to the baggage compartment. The centre two seats can be slid slightly inboard to allow them to rotate while a table can be pulled up out of the sidewall.
Two additional rear seats are supplied, and these can be installed on the cabin rails when the maximum seat count (two cockpit, eight cabin) is required.
Behind the flight-deck on the starboard side opposite the main entry door is the other creature comfort expected of a luxury business aircraft: the toilet.
Two doors open to allow privacy for those wishing to use the facilities, the first opens across the entrance to the cabin whilst the second blocks off access to the cockpit.
All cabin seats have individual air outlets and lights; the cabin ceiling has two full-length strip lights to provide full illumination. The windows are fitted with retractable shades whilst the centre window on the starboard side is also an emergency exit.
The PC-12 NG interior is designed to the latest standards not just to look great but also to be in compliance with the latest crashworthiness requirements. Attention is paid to the seat angles and cabinetry so that they can withstand the required g-forces of an emergency landing.
In the driver’s seat
Entering the flight-deck, you are first struck by the modern layout with displays that look as though they could have been fitted to an Airbus A380– there is not one round dial anywhere.
The Honeywell APEX system uses four LCD displays with one in front of each pilot and the other two stacked on top of each other in the centre of the panel. Controlling all this are twin FMSs. The PC-12 NG is fitted as standard with just a single FMS with the second being optional. If a second FMS is fitted, it acts as a back-up to the primary system.
The display in front of each pilot provides the flight instruments and a compacted engine instrument display.
Each Primary Flight Display (PFD) displays the usual airspeed and altimeter tape, compass and CDI display and attitude, and is superimposed over a synthetic terrain display. This enables the pilot to concentrate mainly on just one display.
The two vertical centre displays are used primarily for displaying navigation, Jeppesen instrument approach charts and aircraft systems information as well as the landing gear and flap indicatiors.
To the outboard side of the left PFD is an integrated Emergency Standby Instrument System (ESIS). This is a small combination standby instrument LCD display with airspeed and altitude tape display and attitude indicator that replicate the main PFD should the a failure of the main systems.
Behind the FMS control panel are the usual turbine engine controls that include manual over-ride lever, power control lever and condition lever.
Outboard to the right of the engine controls is the flap lever with selections of 0°, 15°, 30° and 40°. The gear lever is located on the lower panel in front of the left-hand pilot.
The overhead panel contains the main electrical system switches and engine starter and fuel pump switches. The other electrical system switches and circuit breakers are located on the sidewalls outboard of each pilot’s seat.
Taking the left seat in the PC-12 NG is just a little awkward but this is eased with the help of a large grab handle situated in the middle of the windscreen just below the standby compass.
The seat is adjustable fore aft and vertically. To achieve the correct vertical position, there are a couple of small blue and white ball-shaped indicators just below the standby compass, which, when lined up in line with each other, indicate the correct height. The rudder pedals are also adjustable fore and aft.
The visibility over the high instrument panel is just a little limited as expected with such a long nose section; however, the visibility to the sides and rear is excellent, so much that the wingtips are easily visible without straining. You can almost see back to the tailplane tips.
When seated, all controls and instruments were clearly visible without and straining or excessive head movement. Obviously it’s BMW Design’s attention to detail that has helped here.
Lighting the fire
After we had run through the Before Start Checklist, it was time to start the big PT6. Unlike a recent review on another PT6-powered aircraft, the start procedure on the PC-12 was a little more automated.
After pressing the starter button, the only other action required was to move the condition lever forward to Ground Idle as the RPM passed 13%. There was no need to deselect the starter after reaching 50% as this is done automatically by the control system.
Apart from the normal avionics start-up procedures associated with these modern systems, the only procedure peculiar to the PC-12 NG is a test on the stick pusher system. The stick pusher is part of the stall protection system, which recognises the approach of a stall and warns the pilot. If nothing is done the system will push the stick forward.
After our planned route from YPAD to Kingscote on Kangaroo Island via a SID was loaded and an airways clearance requested, we were ready to taxy.
The Pilatus moved forward easily and with a slight touch of the brakes to get the feel, I turned out of the parking area en-route to Adelaide’s runway 23.
Taxy speed is controled with power by moving the power lever back over the detent below the idle stop into the beta range. This technique controls the propeller thrust and avoids the need for heavy braking.
One unnerving thing I noticed on the way out to the runway was that every time I moved the rudder to turn, the yoke moved in roll as well. This is because a spring interconnect is fitted between the rudder and the ailerons.
With the flaps set to 15° and the condition lever set to Flight Idle, we were cleared for take-off. I must admit I was a little too aggressive in my application of take-off power, With all those automated systems that can handle much faster power applications, I was lulled into a false sense of protection and had to control things a bit more with that big prop out the front.
The PT6 has an inertial separator in the intake duct to protect the engine from icing, foreign object or bird ingestion, but it is the pilot that will protect the propeller from potential damage.
The acceleration was quite rapid, and as approached the rotate speed of 80 knots, a little back pressure was all that was necessary to get the PC-12 NG airborne.
Above a safe height, and with a little tap on the toe brakes, the gear was selected up. With climb established at 100 knots, the flaps were retracted and the yaw damper engaged. Speed was increased to 120 KIAS.
With our track displayed on the FMS map, we engaged the autopilot and the APEX system accurately controlled our flight to Kangaroo Island. To allow more time to explore the capabilities of the FMS, we slowed the cruise back to around 160 KIAS at 10,000 feet. Normally this would have been closer to 200 KIAS.
To fully check-out the integration of the FMS we decided to let down into Kingscote via the RNAV-Z runway 19 approach. Also, we entered the procedure via the holding pattern, which the FMS handled with ease.
Inbound to Kingscote
As we commenced the approach, ATC passed us traffic on a Diamond DA42 departing Kingscote. Separation with this aircraft was clearly displayed on the active traffic system on the PFD as tracked towards ‘Kingscote November Charlie’.
Using the autopilot made the approach very easy. The automatics were disconnected at just above the approach minima of 600 feet, so I could get a feel for the aircraft in the approach configuration.
The flaps on the PC-12 are large-span, slotted Fowler flaps that extend rearward as well as down to both increase wing area as well as camber.
On approach I found the elevator trim forces a little high, until I was told that to operate the yoke-mounted elevator trim switches, you first have to squeeze a trigger switch on the front of the yoke to enable the hat switch. This prevents trim run-aways.
The hat switch trims the ailerons, while yaw is trimmed with a rocker switch on the front of the engine power lever. The indicators for all the trim systems are displayed on the lower MFD and display in green when in the normal range.
After I discovered this secret, it was much easier to trim the aircraft for a stable approach at approximately 85 KIAS. When I say “approximately” I mean “approximately”, because unlike other aircraft where the pilot will calculate the threshold speed, in the PC-12 NG, you approach at the bug speed calculated by the FMS with the known weight. This is the Dynamic Speed Bug (DSB) and equates to 1.3 times VS and is displayed as a green bug on the airspeed tape.
With the yaw damper off and the power reduced to idle, the Pilatus settled onto runway 19 just a little off the centreline with a little over 10 knots of crosswind. The PC-12 has a crosswind limit of 30 knots with 0° flap, reducing to 15 knots with full flap.
We performed a touch and go to depart overhead Kingscote to further explore the handling qualities of the PC-12 NG.
Once clear on top of the cloud over Kangaroo Island, I had a look first of all at the roll rate. I initially found the roll rate to be a little slow compared to most other general aviation types at close to five seconds from 45 to 45.
Switching off the yaw damper had an immediate effect, with the roll rate feeling much crisper, and the time reduced to 3.5 to 4 seconds for the same roll change. All I had to do was use a little more rudder to balance the aircraft.
Next I explored the stalling characteristics. When approaching the stall in the clean configuration, you get a voice alert of the approaching stall and just as the buffet started the stick pusher activated, shoving the nose down and unstalling the aircraft.
The one big difference I noted with the PC-12 stall was that as the speed reduced significant aileron input was required to keep the wings level. This could be attributed to the large torque effect of the big prop on the 1200 hp PT6.
We returned to Kingscote and did a couple of circuits on runway 19 and then 01 after the wind swung around. Flying the big Pilatus around the circuit was very straight forward and with such great visibility, any traffic was easily seen.
The only time the runway wasn’t visible from the cockpit was the short upwind leg. As soon as the crosswind turn was commenced, the runway came into sight and visual manoeuvring was straightforward. This would be a great advantage when breaking out of weather on an airfield that requires a circling leg at the end of the let-down.
On departure from Kingscote we climbed up to 10,000 feet again and tracked by the DUFFY 3 arrival back to Adelaide to carry out an ILS approach onto runway 23.
At 10,000 feet in cruise, a little ice collected on the windscreen. The windscreen heating and the anti-icing boots were switched on. At the time there was no icing visible on the wing leading edge. If this was to occur at night, a light illuminates the leading edge to make any ice visible. The left-hand light must be operative before flying into icing conditions at night.
The approach back to Adelaide was just like flying a big jet on an ILS approach with the only differences being the non-availability of an auto-throttle system and much lower speeds.
After a bit of float resulting from carrying a little too much speed, the touch-down was on the centreline, and with reverse selected, minimal braking was required to make the first taxyway exit.
Throughout the flight I had flown the PC-12 NG using the Dynamic Flight Vector display on the PFD attitude display. This is a small indicator on the pitch ladder that shows your exact flight path in space.
If you wish to fly level, place it on the horizon line and the aircraft’s flight path will be level; placing it 3° down on a glide path will maintain that 3° flight path. This not only revolutionises instrument flying, it makes it so much easier by selecting the exact flight path required.
When I asked Simon why he chose the PC-12 NG over other aircraft, he said he had always appreciated the Pilatus design and that with this aircraft he could travel just about anywhere that he might want to go; from unsealed strips up north in South Australia and anywhere else in Australia that he want to go to for business or pleasure.
Simon’s transition onto the PC-12 NG started as mentioned with a ground course at Pilatus’s facility in Adelaide followed by training in a PC-12 NG in Adelaide. With this experience under his belt Simon set off to Switzerland with Pilatus’ Demonstration Pilot, Peter Tippett, to pick up and ferry Simon’s aircraft VH-TCP to Australia via Crete, Egypt, Oman, India, Thailand, Vietnam, Bali, Broome and Adelaide: a total of 49 hours flying.
“The aircraft performed perfectly on the flight,” he told me. “I found it remarkable [having had quite different experiences with other new aircraft] that we could take delivery of this new aircraft, load it up and fly it across the planet with literally zero ‘squawks’. That was very impressive - as was the extremely high standard of build quality of the aircraft in general.”
As a result of the experiences of this flight, Simon tells me that he would contemplate attempting this sort of flight again for pleasure with the family; he is that impressed with the capabilities of the PC-12 NG. So far he has taken the aircraft to Margaret River in Western Australia and Port Macquarie in the east and has enjoyed every minute of flying it.
Simon fully intends using the aircraft not only for pleasure, but serious business as well as doing some commercial work. It’s definitely a workhorse aircraft, built to fly regularly.
Simon’s adventure can be found on http://simonhackett.com.
Simon’s experience with the PC-12 NG proves that Pilatus build an aircraft that can be flown by pilots with lowish flight hours like Simon’s 1500 hours split between gliders and powered aircraft.
Because of its single-engine layout without having to worry about the complications of asymmetrics, the PC-12 NG is just a big single-engined GA aircraft really.
Like their watches, the Swiss have really done their homework in the design and construction of the PC-12 NG as proven by the number in service around the world.
My thanks to Sebastian Lip and Peter Tippett of Pilatus and of course Simon Hackett for making his aircraft available for this review.
Wingspan: 16.28 m
Length: 14.4 m
Height: 4.26 m
Wheel Track: 4.53 m
Wheel Base: 3.48 m
Cabin Lengt: (excluding cockpit) 5.16 m
Cabin Width: 1.52 m
Cabin Height: 1.47 m
Cabin Width @ Floor: 1.30 m
Internal Baggage volume: 1.13 m3
Max Take-off Weight: 4740 kg
Max Landing Weight: 4500 kg
Max Zero Fuel Weight: 4100 kg
Basic Operating Weight (Executive Config): 3076 kg
Usable Fue: 1226 kg
Payload with Full Fue:l 458 kg
Max Cruise Speed: 280 KTAS
Max Range: 1830 nm
Max Operating Altitude: 30,000 ft
Cabin Altitude @ 26,000 ft: 8,000 ft
Takeoff Distance over 50’: 2,650 ft
Rate of Climb (MTOW): 1,920 ft/min
Landing Distance over 50’: 1,830 ft
Stall Speed (MTOW: 67 KIAS