 Brake railway - Air brake enhancements: Encyclopedia II - Brake railway - Air versus Vacuum brakesThe biggest advantage that air brakes have over vacuum brakes is that the maximum pressure is 70psi instead of only 17psi. Air brake equipment can thus also be smaller and lighter. This advange increases at high altitude, e.g. Peru.
The main advantage for vacuum brakes is that the vacuum can be created by a steam ejector with no moving parts, whereas an air brake system requires a noisy pump.
By and large, the vacuum brake has lost the battle for new systems, and many vacuum braked systems change ...
See also:Brake railway, Brake railway - Air versus Vacuum brakes, Brake railway - Air brake enhancements, Brake railway - Accidents with brakes Read more here: » Brake railway: Encyclopedia II - Brake railway - Air versus Vacuum brakes | 
