Civil engineer guide to fighting positions, shelters, obstacles

AFH 10-222 Volume 14 1 August 2008 27
2.5.1.4. Grenade Sumps. Determining where to locate grenade sumps depends
on the type of fighting position being constructed. For a one-person
fighting position, grenade sumps (Figure 2.4) should be dug into the bottom
front face of the position at approximately a 30-degree angle and 12 to 18
inches deep, about the length of an entrenching tool. The width of the sump
should be approximately equal to the width of the entrenching tool shovel.
Use whatever tools are available to slope the floor towards the grenade sump.
This will make it easier to kick a grenade into the hole and get out of the way
so the blast goes into the back wall. For a larger, two-person fighting position,
grenade sumps are usually dug at each end of the position to allow occupants
to move towards the opposite end away from the blast. Avoid locating
grenade sumps under overhead cover, especially if the cover is constructed
across the middle of the fighting position. The blast could reflect off
the cover and cause injuries or collapse the entire structure. A combination of
grenade sump trenches and holes can be used for special-purpose fighting
positions. A T-shaped position allows for additional observation or firing
zones but may require additional grenade sumps. Make sure the blast from
the sump is not directed towards any occupied sections of the position.
Figure 2.4. Grenade Sump – One-Person Fighting Position.