all cars, any individual car braking system can be "cut out." Regulations govern the number of cars per train that
may be cut out or have inoperative airbrakes.
Section II. Handbrakes
6.8. GENERAL
All railway cars must be equipped with some means of slowing down or stopping the car by hand. When
cars are being switched in railway yards, they are frequently in motion with no locomotive coupled to them;
handbrakes are necessary if the trainmen are to control their movement. Two requirements are placed on any
handbrake: it must be capable of stopping the car and it must work in harmony with the airbrake system. You
remember earlier in this chapter it was explained that the handbrake rod is connected to the live cylinder lever
which is in turn connected to the piston rod. The handbrake apparatus is always located on the end of the car
toward which the piston rod is pointing. Through its connection with the live cylinder lever, the handbrake
apparatus can actuate the brakes through the system of rods and levers used in the airbrake system.
There are several types of handbrakes but, in general, all types consist of a handwheel (or hand lever),
handbrake shaft, handbrake rod, and handbrake chain connecting the shaft with the rod. These parts are pictured
in figure 3.4, the illustration showing the brake rigging on a four-wheel truck. Handbrakes are classified as
either horizontal or vertical; either classification may be one of two types: straight shaft or geared. The
classification of a handbrake depends upon the position of the handwheel: if it is horizontal, the handbrake is
classified as horizontal; if vertical, it is classified as vertical. The two types are discussed in the paragraphs that
follow.
6.9. STRAIGHT SHAFT
The typical straight-shaft handbrake has a handwheel or lever connected directly to a vertical handbrake
shaft which is anchored, at the bottom end, in a bracket attached to the underframe as illustrated in figure 6.3. A
chain is attached to this vertical shaft that winds around it as it is turned by the handwheel. As the chain winds
onto the vertical shaft, force is applied to the handbrake rod and consequently to the live truck lever which
actuates the other rods and levers necessary to apply the brakes. Near the top of the vertical shaft, a gear-and-
pawl arrangement holds the shaft in place in the position to which it is turned. The pawl fits into each tooth in
the gear as the shaft is turned. To unwind the chain and release the
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