Gulfstream’s G400 flies with a full cabin and sets a speed record

Gulfstream’s newest jet has reached two milestones. The company announced them on October 19, 2026, the day before the NBAA-BACE show opened in Las Vegas.

A first flight with a finished cabin

The first fully outfitted G400 test aircraft flew for the first time on October 14. It took off from Dallas Love Field, stayed up for 2 hours and 46 minutes and climbed to 48,000 feet.

“Outfitted” means the cabin is fully finished, with seats and fittings in place. Gulfstream says it will use this jet to check cabin systems, how the equipment works and how comfortable passengers are in flight.

The test cabin has 11 seats laid out over two and a half living areas. AvWeb, citing Gulfstream’s published specs, reports the G400 can be set up for up to 12 passengers.

A speed record on the way to the show

Another G400 test aircraft flew from Miami to Las Vegas for the show. The trip took 4h08m at an average of Mach 0.89, on a fuel mix that included sustainable aviation fuel, or SAF, Gulfstream says. The company calls it a new city-pair record.

Mach 0.89 is 89 percent of the speed of sound. A “city-pair record” is a speed record between two named cities.

Gulfstream says three experimental G400 test aircraft are flying. The record jet was one of them.

Where the program stands

The G400 is not yet certified, so it cannot enter service. Gulfstream says the jet has already been tested at high altitude in Telluride, Colorado, and in the cold at Iqaluit, Canada. AvWeb reports that flight testing began in August 2024 and that the jet uses two Pratt & Whitney Canada PW812GA engines.

“With the largest cabin in its class”

Mark Burns, president, Gulfstream

Gulfstream president Mark Burns made that claim about the G400’s cabin. We have not seen an independent comparison, so treat it as the company’s view.

On display in Las Vegas

At the show, Gulfstream displayed a G400 test aircraft and a cabin mockup. They sat alongside the G700, G800, G500 and G600, and a mockup of the new G300.

Gulfstream has not given a date for certification or first delivery in this announcement. We will report it when it does.

Top photo: Matti Blume via Wikimedia Commons, CC BY-SA 4.0. Cropped.