A Boeing removeu a derrapagem nos últimos B777-300 porque eles nunca tiveram uma greve na cauda e uma versão atualizada do FBW praticamente garantirá isso no futuro. Remover o tailskid economiza cerca de 300 lbs.
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Boeing has also decided to remove the tail skid from the 777-300ER as a weight and drag reduction improvement after developing new flight control software to protect the tail during abused takeoffs and landings. “We redesigned the flight control system to enable pilots to fly like normal and give them full elevator authority, so they can control the tail down to the ground without touching it. The system precludes the aircraft from contacting the tail,” Schneider says. Although Boeing originally developed the baseline electronic tail skid feature to prevent this from occurring on the -300ER, the “old system allowed contact, and to be able to handle those loads we had a lot of structure in the airplane to transfer them through the tailskid up through the aft body into the fuselage,” he adds. “So there are hundreds of pounds in the structure, and to be able to take all that out with the enhanced tail strike-protection system is a nice improvement.”
The change was implemented on the line in November and will be offered as a retrofit through a service bulletin. “With a retrofit, you can’t save so much weight because the structure is already in the fuselage, but the drag and maintenance savings is still a nice benefit,” says Schneider. “It is also one of things customers are most interested in retrofitting off the aircraft."
A lógica TSP (Tail Strike Protection) foi incorporada no 777 FBW desde que o -300ER se tornou disponível. Também está disponível no 777-200LR (apesar do corpo mais curto); Acredito que todos os outros modelos também o tenham agora através dos PFCs (200ER, F). A mais nova aeronave -300ER tem a lógica TSP MELHORADA e com ela veio a remoção do patim de cauda, que economiza 323 libras (145kg) de peso da aeronave além dos custos de manutenção (é um patim acionado hidraulicamente).