In The Works: Dassault Falcon 7X

 - October 9, 2006, 1:43 PM

Since the maiden flight of the Falcon 7X on May 5, the 5,700-nm-range trijet has been flying almost daily from Dassault’s flight- test center in Istres, France. By the middle of last month, the 7X had logged 45 hours during 15 flights and had reached Mach 0.82 and 41,000 feet.

“Real-time flight-data analysis and excellent reliability have allowed us to move forward faster than expected,” noted Yves “Bill” Kerherve, senior chief test pilot for Dassault Aviation. “Initial results of the flight-test program have confirmed Dassault’s predictions–the aircraft is incredibly stable and the fly-by-wire controls are extremely precise.”

The test aircraft is typically flown with 15,000 pounds of fuel, giving it a takeoff weight of 54,000 pounds with flight-test equipment. At this weight, the takeoff distance typically has been around 2,450 feet, and climb rates of up to 5,000 fpm have been demonstrated.

Testing for all of the modes of the fly-by-wire controls, including reversionary modes, has been accomplished. The airplane has also landed using fly-by-wire back-up modes.

The second test aircraft will arrive in Istres by the middle of next month and the third test aircraft will arrive later this summer. Falcon 7X S/N 3 will be outfitted with a full interior and will be used for long-range and endurance tests, in addition to interior sound level validation. Approximately 1,200 flight test hours have been allotted before the expected FAA and EASA certification.

Meanwhile, the static and fatigue test 7X airframe has been undergoing tests at the Toulouse Aeronautical Test Center (CEAT) in Toulouse, France, since March. All static and fatigue tests will be accomplished using one test article.

The testing initially concentrated on static testing to support the early stages of flight-envelope expansion during the first several flights of the Falcon 7X, but fatigue trials have now begun and the testing rate is nearing 300 “flights” per day. As of last month, half the 20,000-flight life of a Falcon 7X has been simulated at the CEAT. By the end of this summer, two aircraft lives (40,000 flights) will have been “flown.”

After fatigue testing, the engineers will focus their attention on static trials, testing the airframe up to the design and ultimate load limits. Wing flexing at the wingtips has reached one meter (3.28 feet) but will increase to 1.8 meters (5.91 feet) during ultimate load static trials.

FAA and EASA certification and first deliveries of the Falcon 7X are expected late next year.