Impossible? No, just unlikely.
The fairly long Air Force Ambigram displayed to the left certainly catches your eye with the way the letters come together.
As you can see this design reads 'Air Force' when upright and also reads 'Air Force' when upside-down.
Simply mouse over the design to see it rotate.
All items in the FlipScript store are already displaying the Air Force Ambigram. To see them, use the menu bar at the top to navigate to an item and every product will display the Air Force Ambigram.