This is 20,000 feet higher than most subsonic airliners.

这比多数的次音速客机要高上两万英尺。

I have no idea what subsonic speed is.

我实在不明白什么是亚声速。

One more thing. This is a subsonic impact sensor.

还有个玩意儿。这是个次音速冲击传感器。

This paper introduces the MYS-Type subsonic gas burner.

本文介绍了MYS 型煤气亚高速烧嘴的研究成果。

Future Aircraft Team Presentations for Subsonic concepts.

未来飞行器团队报告：亚音速概念。