The US-Australian objective was to drive out Viet Cong (VC) unit who had taken up positions on several key hills in War Zone D in an area about 17.5 miles (28.2 km) north of Bien Hoa.

On 5 November, the 173rd Airborne Brigade received intelligence indicating that a VC regimental headquarters, mistakenly reported as belonging to the 272nd instead of the 271st, its three battalions, and the 274th Regiment's D800 Battalion were massed near the confluence of the Dong Nai and Song Be rivers in War Zone D. About twenty-two kilometers northeast of Bien Hoa Air Base, the area had been entered by the Americans several times before.

The brigade's third maneuver element, the 2nd Battalion, 503d Infantry, commanded by Lieutenant Colonel George E. Dexter, remained in reserve at Bien Hoa.

[1]: 76 Early on the morning of 5 November the artillery battalion, accompanied by Troop E, 17th Cavalry Regiment, and Company D, 16th Armor, went into Position Ace (11°03′36″N 106°55′55″E / 11.06°N 106.932°E / 11.06; 106.932), east of the Dong Nai and about 8 km southwest of its junction with the Song Be.

The Australians set up very close to their landing zone, which was located near a paddyfield that stretched east and south towards small hill masses ranging up to 25m in height.

[1]: 77 Units from the two battalions began working outwards to the south and east of their bases on 6 and 7 November, employing company and platoon-size patrols.

Both did, however, uncover empty camps complete with supplies and equipment, bunker and tunnel complexes, and a number of booby-trapped huts.

The chaplain accompanying the battalion, Captain James M. Hutchens, subsequently wrote that one of the patrols found fresh footprints less than 1 km from the unit's camp and also heard the "occasional muffled cackling of chickens," which VC soldiers carried for food.

Whatever the troops found, VC historians would confirm later that the 271st's 3rd Battalion was in the area and that it received orders on the morning of the 8th to attack Tyler and his men.

Claymore mines exploded and sheets of fire from carefully positioned .30 and .50 caliber machine guns engulfed the troopers.

In the fighting that followed, B Company moved into the breach from the northeast to break the envelopment often relying on fixed bayonets to repel daring close range attacks by small bands of VC fighters.

Together they managed to establish a coherent defensive line, running around the hilltop from southeast to northwest, but with little cover on the southern side.

[1]: 79 Although the fighting continued after the second massed attack, it reduced in intensity as the VC troops again attempted to disengage and withdraw, scattering into the jungle to throw off the trail of pursuing U.S forces.

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 figure of 400 turned out to be a guess, however, which Williamson made in the immediate aftermath of the battle under pressure from Military Assistance Command, Vietnam headquarters.

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.

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.