What is QFE and how does it differ from QNH?

• A. QFE sets the altimeter to read height above the local field elevation; QNH sets altitude above mean sea level
• B. QFE sets altitude above mean sea level; QNH sets height above field elevation
• C. QFE and QNH both set altitude above field elevation
• D. QFE has no relation to altitude

Answer: (A)

Understanding altimeter settings is about what height the instrument is actually showing when you set the pressure reference. Setting the altimeter to QFE makes it indicate height above the local airfield elevation, so on the ground at the airport the reading would be zero. Setting it to QNH makes the altimeter indicate height above mean sea level, so on the ground the reading corresponds to the field’s elevation, and in flight it gives your altitude above sea level.

So the best description is that QFE sets the altimeter to read height above the field elevation, while QNH sets altitude above mean sea level. The other statements mix up these definitions or dismiss the relevance of the altitude reference, which isn’t accurate.