Operation Hump was a search and destroy operation initiated on 8 November 1965 by the 173rd Airborne Brigade, in an area about 17.5 miles (28.2 km) north of Bien Hoa. The 1st Battalion, Royal Australian Regiment deployed south of the Dong Nai River while the 1st Battalion, 503rd Infantry, conducted a helicopter assault on an LZ northwest of the Dong Nai and Song Be Rivers. The objective was to drive out Viet Cong fighters who had taken position in several key hills. Little contact was made through 7 November, when B and C Companies settled into a night defensive position southeast of Hill 65, a triple-canopy jungle covered hill.
At about 0600 on the morning of 8 November C Company began a move northwest toward Hill 65, while B Company moved northeast toward Hill 78. Shortly before 0800, C Company was engaged by a sizable enemy force well dug in to the southern face of Hill 65, armed with machine guns and shotguns. At 0845, B Company was directed to wheel in place and proceed toward Hill 65 with the intention of relieving C Company, often relying on their combat knives and bayonets to repel daring close range attacks by small bands of masked Viet Cong fighters.
B Company reached the foot of Hill 65 at about 0930 and moved up the hill. It became obvious that there was a large enemy force in place on the hill, C Company was getting hammered, and by chance, B Company was forcing the enemy's right flank.
Under pressure from B Company's flanking attack the enemy force—most of a People's Liberation Armed Forces (Viet Cong) regiment—moved to the northwest, whereupon the B Company commander called in air and special napalm tipped (it's doubtful there were any napalm artillery shells, perhaps they mean white phosphorus shells) artillery fire on the retreating rebels. The shells scorched the foliage and caught many rebel fighters ablaze, exploding their ammunition and grenades they carried. B Company halted in place in an effort to locate and consolidate with C Company's platoons, managing to establish a coherent defensive line running around the hilltop from southeast to northwest, but with little cover on the southern side.
Meanwhile, the PLAF commander realized that his best chance was to close with the US forces so that the 173rd's air and artillery fire could not be effectively employed. PLAF troops attempted to out-flank the US position atop the hill from both the east and the southwest, moving his troops closer to the Americans. The result was shoulder-to-shoulder attacks up the hillside, hand-to-hand fighting, and isolation of parts of B and C Companies but the Americans held against two such attacks. Although the fighting continued after the second massed attack, it reduced in intensity as the PLAF troops again attempted to disengage and withdraw, scattering into the jungle to throw off the trail of pursuing US snipers. By late afternoon it seemed that contact had been broken off, allowing the two companies to prepare a night defensive position while collecting their dead and wounded in the center of the position. Although a few of the most seriously wounded were extracted by USAF helicopters using Stokes litters, the triple-canopy jungle prevented the majority from being evacuated until the morning of 9 November.
The result of the battle was heavy losses on both sides—48 Paratroopers dead, many wounded, and 403 dead PLAF troops.
Operation Hump is memorialized in a song by Big and Rich named 8th of November. The introduction, as read by Kris Kristofferson, is:
“ On November 8th 1965, the 173rd Airborne Brigade on "Operation Hump", war zone "D" in Vietnam, were ambushed by over 1200 VC. Forty-eight American soldiers lost their lives that day. Severely wounded and risking his own life, Lawrence Joel, a medic, was the first living black man since the Spanish-American War to receive the United States Medal of Honor for saving so many lives in the midst of battle that day. Our friend, Niles Harris, retired 25 years United States Army, the guy who gave Big Kenny his top hat, was one of the wounded who lived. This song is his story. Caught in the action of kill or be killed, greater love hath no man than to lay down his life for his friend. ”
The final sentence is a reference to John 15:13 in the Bible.