E 级和 A 级空域的区别在于，在 A 级空域，所有操作都需遵照仪表飞行规则，飞行员必须要有仪表等级，也就是说，要有操作航空仪表方面的技术和执照。

The difference between Class E and A airspace is that in Class A, all operations are IFR, and pilots must be instrument-rated, that is, skilled and licensed in aircraft instrumentation.

youdao

然而，如果飞行员持有的仪器等级在其必须持有的基本的飞行员执照等级之上，那么飞行员只能选择仪表飞行规则。

However, a pilot can only choose to fly IFR if they possess an instrument rating which is above and beyond the basic pilot's license that must also be held.

youdao

仪表等级赋予飞行员控制飞机的能力，而不用参考地面或地平线，只使用飞行和导航仪表。

The Instrument Rating gives the ability to control the aircraft without reference to the ground or horizon, using flight and navigation instruments.

youdao