Falcon 8X Raises Bar for Range and Cabin

 - June 1, 2014, 5:10 AM
The Falcon 8X will have a range of 6,450 nm, a gain of some 500 nm over the company’s 7X.

Dassault continues to expand the Falcon series, launching the new ultra-long-range 8X at the EBACE show on May 19 just seven months after unveiling the 5X at last October’s NBAA Convention. The 8X is a derivative of the 7X trijet, introducing a longer fuselage and 6,450 nm range, a gain of about 500 nm on the 7X.

Expected to cost around $58 million (10 percent more than the 7X), the 8X is slated to fly in the first quarter of next year, followed by certification in mid-2016 and deliveries in the second half of that year. The first production 8X will go to Serge Dassault, chairman and CEO of Groupe Dassault.

A trio of Pratt & Whitney Canada PW307D turbofans, an improved version of the 7X engines, will power the 8X. Combined with a new wing design, the new powerplants will make the 8X up to 35 percent more fuel efficient than any other aircraft in the ultra-long-range segment, according to Dassault.

This month the French airframer’s Bordeaux Mérignac factory expects to take delivery of the first complete 8X fuselage from its Biarritz plant and the first wing from the Bordeaux Martignas facility. Ground testing of the first complete aircraft will begin later this year. At 42.6 feet in length (3.6 feet more than the 7X’s) and 1,765 cu ft in volume, the 8X’s cabin is the longest of any Falcon. Olivier Villa, senior vice president for civil aircraft, explained that the extra length will have a noticeable effect, allowing the installation of a large aft lavatory with shower and a compliant crew rest area in the front section, sandwiching a comfortable three-lounge cabin in the middle. The stretch is a response to feedback from current Falcon 7X customers, Villa said. Three floor layouts are available, depending mainly on the length the customer specifies for the galley/crew rest area.

Windows have been added as well, with the total number likely to vary between 30 and 34, although the expected standard is 32–including four in the galley and crew rest area. Dassault claims that the 8X cabin, with a ratio of window surface per passenger to cabin surface of 0.16, is one of the brightest on the market and equal to that of the Gulfstream G650 despite the American airplane’s much larger windows. The 8X’s lavatory window can be equipped with an electrochromic dimming system.

Other features include a 3,900-foot cabin altitude at FL410 and the same “whisper quiet” noise level as in the Falcon 7X.

In the cockpit, the pilots will again find fly-by-wire controls and accompanying sidesticks. Dassault has tweaked its digital flight-control system (DFCS) for the 8X, and the weather radar will be the Honeywell RDR-4000. A “new generation” of flight management system will equip the 8X, part of the EASy 3 man-machine interface that Dassault has developed in-house. The company also will incorporate the head-up display (HUD) developed for the Falcon 5X. An industry first, it will merge EVS and SVS (infrared and synthetic) vision; a second HUD will be an option.

Falcon 7X-rated pilots will be offered a differences course to add the 8X to their ratings.

Ultra-long-range Class

The 6,450-nm range ushers the Falcon 8X into the ultra-long-range category, a need 7X customers had expressed to Dassault. It opens new city pairs for a Falcon; for example, Beijing and Shanghai are within reach from Los Angeles. Also, the 8X will fly nonstop from New York to Dubai, and from Hong Kong to Johannesburg. Dassault hopes the improved capability from Asian locations will boost sales in that region.

A 6,450-nm flight profile could depart from a 5,900-foot balanced field length at sea level (ISA conditions) and, after 14 hours carrying eight passengers and three crewmembers at Mach 0.80, land in 2,150 feet with NBAA IFR reserves. Dassault engineers have kept the landing speed down to 106 knots, only a tad faster than the 7X’s 104 knots. Cruise speeds remain unchanged.

The range has been made possible by a 3,000-pound increase in fuel capacity, found mainly in fuselage tanks and, to a lesser extent, in the wings. Plugs in the fore and aft fuselage sections provide the stretch, and the landing gear has been beefed up.

The wing, which is more flexible, has been designed for a better lift-to-drag ratio. New winglets further reduce the induced drag caused by wingtip vortices. Dassault made the 8X aerodynamically less stable by giving the horizontal stabilizer a different rigging angle for less drag, but a Dassault engineer noted that the DFCS easily controls this relaxation in stability.

The 8X wing weighs 600 pounds less than the 7X’s, a gain in lightness that offsets the heft added by the fuselage stretch, Villa said. Wing area remains unchanged.

More Power

The PW307Ds each provide 6,725 pounds of thrust at sea level and ISA+17C, 5 percent more than the 7X’s PW307As. At the same time, new Fadec and improved fan seals, impeller clearances and exhaust mixer have reduced specific fuel consumption.

P&WC expects to receive certification for the PW307D in March next year but will start delivering preproduction engines to Dassault shortly. The three PW307Ds that will power the 8X on its first flight have already flown on Pratt & Whitney’s Boeing 747 flying testbed.

Asked about the proximity of the 8X development timeline to that for the Falcon 5X (due to fly before the middle of next year and enter service in the first half of 2017), Villa said the schedule is “a consequence of progress in preliminary designs; that’s the way it happened, and we can do it,” noting that this is the first time Dassault has faced the investment required to run two such development programs in parallel.

Direct operating costs (DOC) for the 8X are estimated at $4,075 per hour, using the Conklin & de Decker method, a figure that Villa characterized as comparing favorably with the Gulfstream G550 and Bombardier Global 6000. A key factor in the DOC is maintenance: the 8X will dispense with the 7X’s two-month basic visit interval, so time between inspections becomes 800 hours flying time or one year, whichever occurs first.

Dassault intends that the 8X’s dispatch reliability rate at entry into service will match the 99.7-percent average of the mature Falcon fleet.

Over six years, at 600 flight hours per year, Dassault claims the Falcon 8X will be significantly more economical to own than its competitors. The French airframer calculates that the 8X will cost $22 million, while the G550 will cost $30.5 million and the Global 6000 $33 million. A higher resale value accounts for part of the difference, according to Dassault.

Sales expectations are high, with Dassault planning to ramp up production to 33 per year.