Air crash investigators at the Paris-based BEA have been working on the theory that the speed sensors, known as pitot tubes or probes, malfunctioned because of ice at high altitude.

总部设在巴黎的BEA空难事故调查局做出推测：飞行传感器，也就是空速管和探针由于高海拔结冰而出现故障失灵。

youdao

In addition, rescuers may easily get exhausted working at a place with an altitude of above 4, 000 meters.

此外，在海拔4000米的高处，救援队员们很容易精疲力尽。

youdao

In addition, rescuers may easily get exhausted working at a place with an altitude of above 4,000 meters.

此外，在海拔4000米的高处，救援队员们很容易精疲力尽。

youdao

In order to get the widest possible view, the airplane climbed to 22, 000 feet, twice its normal working altitude.

NPR: Crop Cops Take to the Sky

Fossett will use a bigger balloon this time, and control its altitude by working a propane ethane burner.

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