AK20F means 80% nitric acid + 20% N2O4 + fluorine passivant
AK = Azotna Kislota = Nitric Acid in
NASA
Similar to AK20F
ABT - Approximate Burn Time
ABU - Analog Back- Up
ABU - After Body Unit
ABUP - Auxiliary Back- Up Plate
ABV - Above
ABV - Air Bubble Vehicle
AC - Aerodynamic Center
View all in NASA