(3) Deceptive Screens. A unit can use either large-area or small-area smoke screens as
deceptive smoke screens. It can place deceptive smoke screens over unoccupied areas to confuse the
enemy concerning friendly unit positions and intentions. The engine sound of the M113A2 gives
credence to the deceptive smoke screen the M1059 produces while moving; the sound may be
interpreted as indicating the presence of mechanized vehicles in the screen.
b. M157/M998 Motorized Smoke System. The M157/M998, like the M1059, possesses the
capability to make smoke while moving. The M157/M998 supports operations conducted by motorized,
dismounted, and rear-area units. The M157/M998 has an advantage over the M1059 in that the M998
HMMWV can maneuver into areas and over terrain that are inaccessible to the M113A2 APC. Also, the
M998 HMMWV is faster than the M113A2 APC, and its engine is quieter, allowing a degree of stealth.
A disadvantage is that the M157/M998 does not provide the degree of crew protection offered by the
M1059. Also, the fog oil tank in the M157/M998 holds only 80 gallons, as opposed to 120 gallons in
the M1059 fog oil tank. Discussion of the uses of the M157/M998 follows.
(1) Large-Area Smoke Screens. The M157/M998 can provide large-area smoke screens --
To conceal troop and vehicle assembly areas.
To conceal troop and vehicle movement (including attacks and withdrawals).
To conceal road and bridge complexes along main supply routes.
To conceal construction of battle positions.
To restrict enemy movement and/or force enemy deployment from convoy formations
To conceal rear-area support areas.
(2) Small-Area Smoke Screens. The M157/M998 can provide small-area smoke screens --
To conceal recovery of wounded personnel.
To conceal assaults.
To conceal breaching of minefields or barriers.