The petition could be just a trial balloon to test the administration's reaction.

这次上诉可作为测试政府反应的一个试行方案。

《柯林斯英汉双解大词典》

That is the theory, at least. So far, apart from some low-altitude test flights, the only stratospheric tests have involved a scaled-down version tethered to a weather balloon.

这些就是目前的原理，迄今为止，除了一些在低海拔的飞行测试，唯一的平流层测试是涉及一个按比例缩小拴在气象气球上的模型。

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So far, apart from some low-altitude test flights, the only stratospheric tests have involved a scaled-down version tethered to a weather balloon.

目前对飞船只进行了一些低海拔的飞行测试，平流层的测试则仅仅是由气象探测气球负载着规模缩小的模型原型机来进行的。

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"Each time we renew the license, we check up the balloon and we test the pilot, " Sherif said.

NPR: Fiery Balloon Accident Kills 19 Tourists In Egypt

Some of the changes for volunteers include a physical fitness test, lessons in the physics of balloon-handling and a free three-month gym membership to help them shape up.

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