While visual approaches typically don't require any assistance from instrument-landing systems, safety experts said some airlines prefer to have pilots rely on them as an additional safeguard under nearly all circumstances.

尽管目视进场通常不需要任何仪表着陆系统的辅助，但安全专家说，一些航空公司倾向于让飞行员在几乎所有情况下都将这些系统作为安全辅助。

Investigators also are expected to examine if pilot fatigue or flight-control problems contributed to the accident, and whether air-traffic control instructions may have been a factor.

预计调查人员还将调查事故是否是飞行员疲劳或者飞行控制问题造成的，以及空中交通控制指令是否是造成事故的一个因素。

The aircraft should have been flying roughly 100 or 150 feet above the airport's surface when its tires or tail apparently smacked into a stretch of the sea wall and the jet began breaking apart, experts said. Large pieces of the tail section and scrape marks were visible near the sea wall, and both left and right portions of the landing gear were found hundreds of yards away from the main wreckage.

专家说，当这架飞机的轮胎或者尾翼撞入防波堤并且机身开始后解体时，它本应在距离机场地面大概100英尺或者150英尺的高度上飞行。防波堤附近可以看到机尾的大块残骸和刮痕，左右两侧起落架在距离飞机主体数百米的地方被找到。

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