BLUF: Never operate the M1-series tank without the rear splash guard (also known as skirt #7) in place and carefully open skirts to avoid injury.
Crewmen, operating your M1-series tank without the rear splash guard (also known as skirt #7) can lead to big trouble.
Missing rear mud guard (skirt #7) can lead to engine damage
Running your tank without the rear splash guard allows dust, mud and other debris to overwhelm the pulse jet system (PJS) that keeps the V-packs clean. If the V-packs get dirty, this can lead to very expensive engine damage or even complete engine failure due to foreign object damage (FOD).
So bottom line, always make sure the rear splash guard is installed before driving your tank.
Keep in mind that your tank’s skirts are very heavy. Never open skirts 1 and 2, skirts 3 and 4 or skirts 5 and 6 at the same time because they are on the same hinge line. Also, check for missing hinge pins before opening a skirt. Opening two skirts on same hinge line or opening any skirt with a missing hinge pin can cause the skirt to fall and injure someone.
Find more information in TM 9-2350-264-10 (Sep 11, w/Ch 4, Jan 18) for the M1A1, TM 9-2350-388-10 (Jan 18, w/Ch 2, Oct 21) the M1A2 SEPv2 and TM 9-2350-412-10 (Apr 20, w/Ch 1, Jan 22) for the M1A2 SEPv3.