Tinseth: Multiple Changes Will Result In Reduced Weight And Drag, Increasing Fuel Efficiency

Boeing has unveiled a series of product improvements that will be available on the 777-300ER, the 777-200LR and the 777 Freighter. Boeing's Randy Tinseth announced the upgrades at the ISTAT Americas conference in Arizona this week.

Tinseth wrote on his blog on the Boeing website that baseline engine, airplane weight and aerodynamic improvements will be phased into production by the third quarter of 2016, lowering trip fuel use by 2 percent. Combine that with priced optional features and airlines will see an approximate 5 percent overall fuel use per seat improvement.

Tinseth said that the planemaker will offer a combination of various GE 90 engine improvements by GE. Optimized interior structural crown architecture, low density hydraulic fluid, lightweight insulation and tail skid removal will result in a 1,200 lb. weight reduction.

He also said that a "divergent' trailing edge device added to the underside of the wing, outboard of the aileron increases camber of the outboard wing, resulting in outboard wing efficiency.

Elevator seals are improved to reduce drag and the pitch trim software logic is revised, enabling the elevator to augment the stabilizer trim during cruise flight, reducing profile and induced drag, and the slat trailing edge is made 60 percent thinner, resulting in lower drag.

The inboard flap track fairing is revised to optimize span-loading and reduce profile drag. A new passenger window and seal design will result in greater flushness with the fuselage skin, reducing excrescence drag.

Finally, enhanced tail skid protection is integrated into the fly-by-wire control laws, eliminating the need for a physical tailskid on the 777-300ER.

Tinseth said that the company is also considering retrofit opportunities for in-service airplanes—and GE is considering an engine retrofit package.

(Image provided by Boeing)

FMI: www.boeing.com