Inside Gulfstream’s Testing Program
There are seven G700’s that have been involved in the regime.
Gulfstream’s G700 test fleet has gone through more than 1100 hours of flight testing since the first aircraft took off on Valentine’s Day, 2020. The company yesterday provided an update for its flagship, which not only boasts the largest, most technically advanced cabin among business jets but faster and more fuel-efficient Royce Pearl 700 engines.
“It’s truly a remarkable aircraft,” Colin Miller, senior vice president of innovation, engineering and flight, said on a media call. “The engines are performing flawlessly without missing a beat, and they’re quiet with a very high thrust. It performs well even beyond the normal operating envelope speed and altitude.”
The G700 reached a top speed of Mach 0.99 and a maximum altitude of 54,000 feet. It will have a range of 7,500 nautical miles at Mach 0.85 and 6,400 nautical miles at M 0.90. It takes off within 6,250 feet and the typical landing is 2,500 feet. It cruises between 41,000 and 51,000 feet.
The testing program, which will involve seven G700s, started about a year ago, with the first aircraft using sustainable aviation fuel. The tests for that aircraft involved envelope expansion, flying qualities, flutters and stalls as well as monitoring flight-control systems.
Jake Howard, Gulfstream’s Master Development Test Pilot, said there were many months of preparation for the first flight. “As we moved to that final date, we’re also seeing all the work that went into preparing for it,” he added. “It’s not only a big moment for the flight test engineers, but also anyone who has worked on the project. We enjoyed coming back and sharing the moment with everyone who had been involved.”
Howard praised the G700’s “excellent” handling qualities. “The aircraft is very predictable and a real pleasure to fly,” he said.
The second aircraft, which took off on March 20, tested the winglet and wing-ice shape while performing stall testing and cold-weather testing. “We looked at the aircraft in minus 40 degrees conditions and it didn’t miss a beat,” says Miller.
The third flight in May tested flight controls, engine and thrust reversers, climb performance and loads. The fourth flight in October tested avionics, flammable fuel drainage, and reliability. The fifth aircraft focused on lighting, crew workload, data concentration network and further avionics tests.
“The Symmetry Flight Deck avionics testing was performed in Chicago, Van Nuys, San Jose and Oakland,” said Miller. “It included the pure predictive landing performance system, enhanced flight vision system, dual head-up displays and synthetic vision on HUD. This flight deck makes it a joy to fly this aircraft.”
Two more aircraft with fully outfitted interiors will be added to the test program.
Miller said development testing will continue, while “company and certification” tests will follow, as the G700 proceeds towards FAA certification. “In terms of the number of hours for testing, we’ll do whatever it takes,” says Miller. “We’re very thorough and robust with the testing and it will involve a few thousand hours total. But we don’t try to get to a certain number of hours. At the end of the day, it needs to be a safe and compliant aeroplane.”
The fist G700s should be delivered to customers in the fourth quarter of 2022.