In February of 1967, one of our transport helicopters was converted into a smoke laying helicopter. This conversion was done in the hangar at Soc Trang, and consisted of a bladder tank about 14" square and the width of the helicopter, connected to a preforated ring around the exhaust of the engine. I do not remember any details about the plumbing or the pumping system. The helicopter was armed with a M1917A2 .50 caliber machine gun firing out the left side, and a hand cranked 40mm grenade launcher out the right side. I do not remember the tail number of this helicopter, but I believe that it's nose art was a series of childrens toys, a Dennis the Menace like child, and the legend "Little Toons". On Easter Sunday, 1967, it got a most spectacular field test. The 175th Assault Helicopter Company set out on a "routine" reaction force mission, and stumbled into a hornet's nest. When the 80th Medical's helicopter was shot down in the LZ, our batallion commander, Col. Dempsey, took his helicopter in. They were promptly shot down, and Col. Dempsey was killed, although no one knew it at the time. To make a long story short, CWO Daly and his crew flew the smoke ship, which we called Viking surprise, on repeted runs laying down a continuous smoke screen while every gunship in the delta flew in a circle providing suppressive fire while four slicks went in to retrieve the downed americans. Note that they were not interested in the downed Viet Namese, which says a lot about why we lost the war. After completion of this mission, the aircraft was so badly shot up, that it was not salvagable. The crew said that the hits on the ship were so frequent, it was like hearing hail hit a tin roof. I do not remember which helicopter was selected to replace this one. This might be a good place to note that some helicopters would lift more weight than others, and everyone knew which were which. For instance, 64-13663, "The Honey Bucket", was notoriously weak, while 64-13664, "The Georga Peach", would lift anything that you could get into her. Engine changes made no difference, so it must have been some difference in how they were rigged. I wish I knew.