The first Boeing 777-300 had a "flawless" maiden flight from the company's Everett site on 16 October, completing the 4h 6min test mission at Boeing Field, Seattle, with no technical problems.
Boeing 777 programme chief pilot Frank Santoni says: "We spent 4h shaking the aircraft down thoroughly. You might expect to see some discrepancies, but we didn't get any squawks and we had no EICAS [engine-indication and crew-alerting system] messages." General handling qualities were tested during the flight and, despite the 10.2m fuselage stretch, the 73.9m-long aircraft "felt remarkably similar" to the -200, he adds.
Flight-test chief pilot John Cashman, who was first officer for the -300 sortie, notes that the only major handling difference is experienced on the ground because of the stretched aircraft's longer wheelbase. Ground manoeuvre cameras are mounted in the leading edge of the horizontal stabilisers and beneath the forward fuselage to help taxi the -300 and these were also tested. "We also used it a lot today in flight, because you can see each wing from the tail cameras," says Cashman.
The flight was also a major milestone for Rolls-Royce, which provided the Trent 892 turbofans for the first aircraft. The 777-300, which is the longest jet airliner and largest twin ever built, is the first Boeing widebody to be powered by R-R engines on its maiden flight. The -300 is only the second company jet airliner after the 757 to have its first flight powered by non-US engines. The engines were "trouble-free", says Santoni, who shut each down during the flight to check re-light capability with a windmill air start at 250kt (460km/h). "We treated it just like a production flight," adds Cashman.
Gross take-off weight was well below the -300's maximum of 299,640kg, at 200,440kg, enabling the crew to use a 10% reduced thrust rating for take-off. Although thrust was therefore reduced to around 368kN (82,800lb) per engine, compared to the Trent 892's standard maximum rating of almost 410kN, the -300 rotated just beyond the 4,000ft (1,220m) marker. The aircraft reached a maximum altitude of 17,000ft and a top speed of 250kt during the flight, conducted mostly over the sparsely populated Olympic mountain range to the west of Everett.
After a short lay-up for an internal inspection, the aircraft, WB501, is expected to resume tests on 22October. One of the first-phase test objectives is to clear the high speed envelope beyond the initial 250kt restriction. As the -300 will have a higher maximum operating cruise speed of Mach 0.89 compared to the -200's top speed of Mach 0.87, the aircraft will be tested to a higher dive speed of Mach 0.96, around Mach 0.02 faster than that of the -200.
US Federal Aviation Administration certification is expected in May 1998 with first delivery to launch customer, Cathay Pacific, due later the same month.
Source: Flight International
