Hoping someone on here could help; I'm looking for a point in the right direction for a winch braking query. I have a mass moving horizontally, unspooling a free-wheeling winch as it moves. I'm looking to select a suitable pneumatic caliper disc brake to act as an emergency stop for this winch. From a supplier's website, I've found a fairly general calculation, which appears to allow me to calculate the braking torque required for the rotating mass: T = (W*K^2*N)/308t Where W = weight of the rotating member (lbs) K = Radius of gyration of rotating member (ft) N = Speed of rotating shaft (rpm) t = Stopping time required (seconds). 308 - constant, unsure where this has came from? Now my understanding from this would be that I can take the weight of the rotating member to be the gross weight of the drum, unspooled, which will give me a value for the braking torque required to stop this member at a particular time. Is this a suitable method of identifying braking torque required? If not, does anyone know of any more suitable literature/calcs available I can have a look through? Greatly appreciate any help, many thanks.