The flight test was conducted in the challenging high altitude environment required for refueling of high altitude long endurance (HALE) unmanned aircraft systems (UAS).

这次飞行测试是在充满挑战的高空环境下进行的，这也是高空长航(HALE)无人机(uas)加油所需的环境。

youdao

It's the basic physics that the air is thinner and the resistance to any projectile is less so the flight path of the ball will be different at high altitude.

基本物理学理论上，空气越稀薄情况下，任何物体的耐性都会减少，因此球路也会因海拔高度不同而有所变化。

youdao

The trial was conducted at the company's Airbreathing Test Facility in Orange County, Virginia, and involved a full-scale engine tested at conditions simulating high-altitude, high-speed flight.

此次测试是在公司位于弗吉尼亚州橙郡(Orange County)的吸气式测试设施中进行的，通过模拟高海拔、高速飞行的条件下进行了全面的引擎测试。

youdao

Pilots should be trained on how to handle this event and a high-altitude stall with better technical instruction and flight simulator programs, the report said.

CNN: STORY HIGHLIGHTS

And what - we can't leave out the terminal phase of missile defense, which is things like PAC-3, the Patriot Missile System, and the Terminal High Altitude Area Defense or THAAD, which would shoot down on a threat missile in the final phase of its flight.

NPR: Missile Defense, the U.S. and Europe