Battle of FSB Mary Ann - Conditions Prior To The Attack

Conditions Prior To The Attack

At the time of the attack, FSB Mary Ann was garrisoned by Charlie Company, 1-46th Infantry (75 men commanded by Capt Richard V. Knight). In addition, 18 men from Echo Company's Reconnaissance Platoon were at the base preparing for an operation the following day. These troops shared space with 34 support personnel (medics, radiomen, etc.) from 1-46th's Headquarters Company (HHC). The rest of the garrison (less the ARVN artillerymen) came from elements of Alpha, Bravo, and Delta companies, 1-46th (22 men who were in transit between their units and areas further to the rear), and assorted artillery personnel (including the crew of a quad-.50 caliber machine gun from Battery G, 55th Field Artillery). According to one source all ground surveillance radars and night vision (starlite) scopes formerly at Mary Ann were "sent to the Battalion rear for maintenance." This left the base with a series of ground sensors designed to detect movement located "within fifteen hundred to forty-eight hundred meters" of the perimeter. These sensors had been picking up movement since shortly after the base was reopened, but no contact had ever resulted from the readings.

Charlie Company was the only complete company at Mary Ann due to operations south and east of the FSB near a location called Landing Zone (LZ) Mildred. Companies A and B, 1-46th Inf, were on the ground in that area of operations, and some of the artillery previously located at Mary Ann had been moved to LZ Mildred to support operations there (including the 81mm mortars assigned to both companies and the heavy 4.2-inch mortars normally part of Company E). Prior to the attack, the attention of the Battalion commander (LtCol Doyle) was focused more on operations near LZ Mildred. In fact, the Battalion command post was scheduled to move there on 28 March. This impending move led to a freeze on all new construction at Mary Ann, including fencing to block the roads leading out of the FSB.

Early accounts of the attack state that the defenders "failed to safeguard the perimeter" of the FSB. The only single volume study written about the attack contests this position, pointing out that "historians got it wrong." Even with this new perspective, there are indications that alertness at Mary Ann was not as good as it could have been. Many accounts by men stationed at Mary Ann mention that perimeter security was uneven at best. One member of the 1-46th Headquarters Company stated that "I don't think Captain Knight had a clue as to how lax the security was...because in that area, and only that area, Knight wasn't diligent. He left it up to his lieutenants and sergeants to check the bunker line." In many cases they failed to do so, and the failure was compounded by Charlie Company being understrength and unable to man all the perimeter bunkers. Manning bunkers was not the only problem. Trip flares located in the concertina wire around the base were not always reset or replaced when they went off, a common occurrence caused in some cases by the rotor wash created by large CH-47 Chinook helicopters bringing in supplies or backhauling material as 1-46th Inf prepared to hand the base over to the ARVN. This lax attitude, combined with the skill of the attacking sappers, had fatal consequences for many in Charlie Company. Although not "cringing in their bunkers", the defenders of Mary Ann were not prepared for a ground attack. This lack of readiness was not noted by the 196th LIB commander, Colonel William S. Hathaway during a visit to the base on 27 March, the day before the attack. He later stated that what he'd seen at Mary Ann that day "was a big improvement over that I had seen before...the troops were alert."