ing force but the imminence of tire failure. The 
pilot must insure that the application of brakes 
does not produce some excessive braking torque 
which is greater than the maximum rolling 
torque and particular care must be taken when 
the runway conditions produce low values of 
friction coefficient and when the normal force 
on the braking surfaces is small. When it is 
difficult to perceive or distinguish a skidding 
condition, the value of an antiskid or auto- 
matic braking system will be appreciated.