Meanwhile, a new prospective rival airliner emerged, this time from Boeing in the United States, in the form of the Boeing 727, which also had a tri-jet configuration.[20] Boeing had begun its studies into this sector of the market in 1956, and elected to launch its own tri-jet programme in 1959. Airco executives, who were at the time intensely exploring various alternatives and further partnerships with other aircraft companies, considered the possibility that Boeing might choose to drop the 727 project and instead co-manufacture the Airco D.H.121 in the USA; Lord Douglas was one of the proponents of this initiative.[20] As a result, Airco invited a team of Boeing engineers and executives to Hatfield; (Boeing later permitted a return visit by de Havilland representatives to Seattle); however, Boeing revealed few details of their plans for the 727, while virtually all information on the D.H.121 had been shared with Boeing, an openness that had allegedly "amazed" Boeing.[20] British commentators have tended to interpret this episode as involving the acquisition of sensitive proprietary data on the D.H.121 by a direct competitor.[21] Woods described the action as "de Havilland solemnly handed all its research over to its rivals...the crowning piece of stupidity".[20]
From
https://en.m.wikipedia.org/wiki/Hawker_Siddeley_Trident
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