What can you never use while flying?

An odd title, but it was prompted by the teachings of my primary flight instructor. Years ago, he told me there are three things in aviation that are completely useless to you as a pilot, and that you can never use while flying:

  1. Runway behind you,
  2. Altitude above you, and
  3. Fuel in the truck


To this day, I find that this is still just as true as it was 37 years ago. And that got me thinking - are there any other such ‘quantities’ in aviation that are completely useless to the pilot?

If you know of any, add yours.

2 Replies

Having been a bomber pilot, I would add paratheses to no. 3 and say “(or fuel on the tanker).”


Flight manual in the hangar.  Chart in the hangar.