Flight-testing of Gulfstream's two latest products, the G250 and G650, is proceeding on schedule with the airframer confident that both will achieve their 2011 certification target.

The super-midsize G250's test effort began on 11 December last year, a few weeks after the G650's maiden flight on 25 November. However, data released by Gulfstream at the Singapore air show indicates that the smaller model is further advanced in its development programme.

Trials of the first G250 flight-test aircraft (T1) have seen the flight envelope expanded to 45,000ft (13,730m) and Mach 0.85, says Gulfstream's vice-president international sales Roger Sperry. However, he was unable to provide any similar detail on the test progress of G650 T1, which had its first flight cut short due to a landing gear door vibration, but was back in the air on 4 December.

New Gulfstream G650
 © Jon Ostrower/Flight International

The build effort for the remaining test aircraft and first production airframes for both types is progressing, Sperry says. "The second G250 test aircraft, T2, has reached electrical power-on, and will be ready for first flight in the very near future."

He adds that the first production G250 (S/N 2003) is "coming down the assembly line" and is undergoing system installation, while testing is also under way of the "S1" structural test article.

G650 T1 should be joined "very soon" by the second aircraft: "T2 has been handed over to the flight-test team and is being prepared to fly," he says.

A third flight-test G650 (T3) is in the final production phase, while the first production aircraft (S/N 6004), dubbed "P1", is "coming down the line".

Sperry says both types are on course to receive US and European certification in 2011. The G250 is due to enter service later next year, with the G650 - which is the largest, longest-range Gulfstream ever - following in 2012.

Source: Flight International