After waiting two days for better weather, Boeing took advantage of a brief break in the rain and high winds for the maiden flight of the 777X on Saturday. The aircraft was supposed to fly on Thursday but the test flight was rained out. Winds were too high on Friday but the weather window opened on Saturday about 10 a.m. Pacific time. The first flight was scheduled to last four hours. The aircraft took off from the company’s factory at Paine Field in Everett, Washington, and landed at Boeing Field in Seattle.
The big twin (it’s longer than a 747) taxied to the runway with its wingtips folded up and the tips were dropped after it lined up. The folding tips give an extra 20 feet of wingspan for greater fuel efficiency at altitude but allow the aircraft to use existing airport maneuvering surfaces and gates. The aircraft development has been delayed because of issues with the huge GE9X high bypass engines, which are estimated to be 10 percent more efficient than earlier designs. Boeing is aiming for certification in 2021 and has more than 300 orders for the $400 million aircraft.
10 percent more efficient is a huge deal.
I’m curious what happens if a takeoff is attempted with the tips still folded up. It doesn’t look like they are visible from the cockpit. How about any additional maintenance required?
I’m not a 777 pilot but my guess is that no wingtip deployment would bring on such a cacophony of visual and aural takeoff inhibits and configuration warnings the likes of which would make a takeoff attempt so unlikely as to say “impossible”. Even in older generation aircraft, V speeds and auto throttles are inhibited and aural and visual warnings abound with an actual flap setting different from that which is programmed into the flight management system prior to takeoff.
In other words, the annunciator panel would light up like a pinball machine.
If memory serves from my time working on the 777X program, the computer will not let the pilot advance the throttles if the wingtips are not down and locked.