A lot of pilots are qualified to fly developmental test but they might not have the Weapons School credential that allows Air Combat Command to trust their opinions more easily.

也有许多飞行员可以飞研发试飞，但他们可能没有武器学校的文凭来使空战司令部更轻松地认可他们的选择。

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"The reason we call them test flights or developmental flights is because if you know it is going to work, it's not a test, " he said.

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The makers told us that these were the developmental models, and admittedly, our second test device was far more stable.

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