Under the right conditions, experienced pilots can reach very high altitudes and stay aloft for hours.

在正常情况下，资深飞行员能够将飞机飞到很高的高度，并能够持续飞行几小时。

And they also experimented with parachuting dummies from very high altitudes in the same area.

他们还在同一地区的高海拔地区试验了跳伞假人。

I was just thinking that it's really ironic that the place that we just got back from a couple of weeks ago was very high altitude.

我在想，几周前我们刚从海拔很高的地方回来，这真的令人啼笑皆非。

Of course, you need oxygen to survive, and when the plane is up at a very high altitude, when it is high above the earth, you need that oxygen given to you.

当然，你需要氧气才能生存，当飞机升到非常高的高度时， 当它高出地球时， 你需要氧气给你。