-=======II.  FLIGHT&. FLIGHT CONTROL========  A. FLIGHT CHARACTERISTICS  (1) Static Lift  The lift of an airship is made up of two components -› the static lift and the dynamic lift. These two components  have different physical origins and require separate treat› ment.  The static lift is that component of lift which is due  to buoyancy and which iS independent of any motion of the  ship with respect to the air.  The gross static lift of an airship is the difference  between the weight of the air displaced and the weight of  the lifting gas.  The net lift is the difference between the gross lift  and the gross weight of the ship.  The ship is said to be "light" when the gross lift ex› ceeds the gross weight.  The ship is said to be "heavyn when  the gross weight exceeds the gross lift.  In calculating the gross lift of an airship both the  gas volume and the lift coefficient of the helium, or lift  per 1000 cubic feet, must be  knovm.  The lift coefficient c.an be computed, as indicated be› low, when various conditions of the atmosphere and of the  helium are known.  The gas volume, however, can be determined accurately  only when the ship is fully inflated.  Calculations of gross  lift are largely limi t •ed, therefore to full inflation.  -4-