Overall, half of the respondents said they had been in the dust cloud from the collapsing towers;70 percent witnessed a traumatic sight, such as a plane hitting the tower or falling bodies;

总体来看，有一半的受访者称当时他们被笼罩在大楼倒塌产生的巨大烟尘中，70%的人亲眼目睹了飞机撞上大厦和尸体横飞的恐怖场景；

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The plane gradually out of sight.

飞机渐渐远去看不见了。

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And at the Pentagon the sight of the third plane attack.

在被第三架飞机撞击的五角大楼现场。

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In contrast to past hijacking situations, Mr Learmount said it was unusual that police with weapons appeared in sight of the plane's cockpit.

BBC: How to negotiate with hijackers

Having been to Manhattan a number of times on business, I figured that either the news was completely fabricated or a sight-seeing plane had strayed into some building near New York.

FORBES: Edgefield Federal Prison, Sept 11, 2001

The Lexington Institute's Loren Thompson says those mishaps usually result from a simple break in the line-of-sight connection between a plane and the satellite that controls it--often when one of the aircraft's own wings maneuvers into the path of the signal.

FORBES: Magazine Article