10.3.4 Underbraced
A jib is said to be underbraced when the cantilever runway arm extending from the king post is supported by bracing coming up from below the arm.

Figure 10.3.4-1 Underbraced slewing jib crane
A jib is said to be underbraced when the cantilever runway arm extending from the king post is supported by bracing coming up from below the arm.

Figure 10.3.4-1 Underbraced slewing jib crane