off speed because of premature stalling. Even 
if the airplane with frost were to become air- 
borne at the specified takeoff speed, the air- 
plane could have insufficient margin of air- 
speed above stall and turbulence, gusts, turning 
flight could produce incipient or con plete 
stalling of the airplane. 
The increase in drag during takeoff roll due 
to frost or ice is not considerable and there 
will not be any significant effect on the initial 
acceleration during takeoff. Thus, the effect 
of frost or ice will be most apparent during the 
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