Nice And Niche

But if history is any gauge, the Swiss company’s track record of delivery suggests the PC-24’s first customers can expect an aeroplane delivered on time and that meets or exceeds its promised, quite ambitious specification.

Pilatus has dubbed the PC-24 the ‘super versatile jet’, a marketing phrase that is a little un-Swiss in its immodesty, but one that points to the capabilities of an aeroplane designed to create its own niche in a crowded market.

That ‘super versatility’ is promised by a combination of business jet speed and range combined with the utilitarian qualities of the PC‑12 turboprop – un-jet like short-field performance, the ability to operate from unpaved strips, and a flexible interior that can be configured for passengers, freight or special missions.

Indeed to look at the PC-24’s un-jet like 1. 30m wide x 1. 25m high cargo door is to best understand the aircraft’s claims of versatility. It is a door that will easily facilitate a private owner reconfiguring the aircraft from a sixseat executive jet to a utility transport able to accept standard-sized pallets secured to a flat floor. And it is a door that will easily allow the Royal Flying Doctor Service (RFDS) to load stretcher patients into specially-modified air ambulance-configured PC-24s.

That utility has seen the Royal Flying Doctor Service sign up as a launch customer for the PC-24. Among the firm commitments for 84 PC-24s Pilatus took before closing the order book are four for the RFDS’s Perth-based Western Operations and two for the Adelaide-based Central Operations, with the first expected to be delivered to Australia in the first half of 2018.

“The Royal Flying Doctor is for us such an important launch customer, as they were for the PC‑12,” vice-president for the PC‑24 program, Andre Zimmerman, told Australian Aviation during a mid-year visit to the Pilatus factory.

In all those 84 orders from a customer base of existing PC‑12 operators and new-to-Pilatus customers (including several private individuals in Australia), represents the first three years of PC-24 production, and validates that there is a market need for a ‘super versatile’ jet.

“We were talking to our customers and asked them ‘what do you need, what do you desire from Pilatus as your next aircraft?’ and they said to us basically, in a nutshell, bring us a PC‑12 that goes 100kt faster’,” Zimmerman explained of the genesis of the PC-24.

“So that means a new aircraft with the DNA of the PC-12 – the versatility of a turboprop, volume . . . in the cabin, multi-mission capability, short-field takeoff and landing. But you’re limited with a turboprop single-engine, so there we stepped into a new field and said ‘okay, we have to go to the jet area with two jet engines’. ” Pilatus ran a number of design studies that did look at other configurations such as a single-engined jet and even a twin-engined turboprop with a ‘powerpack’ design (two engines driving a single propeller through a combining gearbox).

“We did a lot of studies but at the end of the day we found out the right way to go is to make a solid, clean-sheet design,” related Zimmerman. “But on the philosophy (side), DNA-wise it is a typical Pilatus product with all the features of the PC-12 that goes pretty much a lot faster. ” The result of that clean-sheet design is an aircraft designed to cruise at 425kt (indeed not 100kt faster than the PC-12 but 145kt faster) at 30,000ft and carry four passengers 1,950nm, while being able to takeoff in as little as 820m (from a dry paved runway at ISA and sea level).

For all that the PC-24 is a conventionally-looking low-wing, t-tail, twinengined jet design. But closer inspection reveals the massive, double-slotted flaps that extend to 37 degrees contributing to an 81kt stall speed while also blocking the engine intakes from FOD kicked up by the main undercarriage.

That main undercarriage features heavy-duty struts and twin main wheels, running low pressure (72psi) tyres. And the design of the rear fuselage sees the twin 3,400lb thrust, dual-FADEC equipped Williams FJ44‑4A turbofans mounted higher off the ground than is the case for other light business jet designs.

Common with other super light business jets such as the Citation CJ4 and Phenom 300 the PC-24 seats six passengers in the main cabin in a typical executive fitout. Range too is similar between all three types (as is the circa US$9 million pricetag), while the PC-24 is a little slower (in the order of 25kt), the main penalty for the aircraft’s ‘super versatility’ of significantly better field performance, a much larger internal cabin volume (14. 2m2), and the ability to easily reconfigure that cabin for a variety of missions, from a four-seat ‘combi’ configuration to all-cargo.

Another unique feature of the PC-24 is a ‘Quiet Power Mode’ for the FJ44 engine which can provide power on the ground (in place of an APU) to run the air conditioning.

Up front is a Honeywell avionics suite (featuring synthetic vision), and the PC-24 will be certified for single-pilot operation.

For flight in icing conditions the PC‑24 features a heated wing leading edge and boots on the horizontal tailplane, while for rough field operations a gravel kit is under development.

“We plan to go together with the RFDS to the outback to really test it when they’ve got their first aircraft,” Zimmerman said of the gravel kit.

“This you can’t design on the computer, you have to see it, you have to fly it, you have to use it, you have to feel it, nosewheel steering for example, how good it works – this [you] will only work [out] when you are out in the dirt. ” In the meantime the company is focused on successful completion of the flight test program. So far two of a planned three aircraft strong flight test fleet have flown, the first prototype, HB-VXA (designated internally as P01) flying on May 11 2015, and HB-VXB (P02) following on November 16.

By the time of our visit the two flight test aircraft had flown almost 600 hours of a planned 2,300 hour flight test campaign, ahead of certification and planned first deliveries in the third quarter of 2017. The third PC‑24, which will incorporate minor improvements identified from the first two aircraft, is due to fly in ealry 2017.

Interestingly, more than half the PC‑24 test program’s flight hours will be completed outside of Switzerland. At the time of Australian Aviation’s visit, P02 for example was in the United States, having completed cold weather testing at the McKinley Climatic Laboratory at Eglin Air Force Base, Florida – “a very positive campaign, it gave us a lot of information on the systems in the aircraft,” said Zimmerman – before flying to Phoenix, Arizona for hot weather testing and autopilot trials.

P01, meanwhile, is “stuffed with flight test instrumentation” as well as a nose boom and flutter exciters on the wingtips and is primarily tasked with aerodynamic and flight envelope expansion testing.

“We’re heading pretty much now towards . . . aerodynamic freeze,” said Zimmerman.

“We’ve had no major surprises,” Zimmerman said of flight testing, noting, for example, that the wing will remain completely clean and won’t require any aerodynamic devices like fences.

That’s an impressive feat for a wing designed to cruise at 425kt and stall at 81kt.

While P01 focuses on aerodynamic testing, P02 is the systems certification aircraft, and P03 will be a production representative aircraft. The fourth PC‑24 to be built will be the first customer delivered aircraft.

Preparing for those customer deliveries means not just the successful execution of the flight test program, but ramping up production facilities.

The Pilatus plant on the shores of Lake Lucerne in the town of Stans, central Switzerland is being expanded with new production and aircraft paint facilities which will allow Pilatus to build 50 PC-24s a year, and staff numbers will grow from around 1,800 today to around 2,000.

“It’s a really big step in every respect, in production, in engineering, in sales and marketing and also concurrently building up the support and sales concept with it,” Zimmerman said of adding the PC-24 to the Pilatus product portfolio.

But it is a big step Pilatus’s history suggests it will easily take – it pioneered the single-engine IFR turboprop ‘niche’ with the PC-12, an aircraft which Pilatus recently delivered the 1,400th example of.

“If you look to the market nobody is waiting for a new business jet [design], there are plenty of new business jets around,” Zimmerman said.

“The only justification for Pilatus to build a new aircraft is that we play the niche, we will always play the niche, and in that niche we are the best. ”