The Vu Gia River valley was only 3 km wide here; steep hills overlooked Thượng Ðức town on the north, west, and south.
ARVN artillery on Hill 52 (15°51′22″N 108°00′07″E / 15.856°N 108.002°E / 15.856; 108.002), near Đại Lộc District, gave effective support to the Thượng Ðức defense and PAVN casualties were high.
Most of the South Vietnamese bunkers and trenches had collapsed under heavy artillery fire, the PAVN controlled the airstrip just outside the camp, and casualties were 13 killed and 45 wounded.
PAVN gunners shifted their concentrations to 2nd Infantry positions and artillery batteries near Đại Lộc, causing moderate casualties and damaging four howitzers.
The tank company from Tân Mỹ Base, in Thừa Thiên province, arrived in Da Nang in good order on 1 August, and Hinh's task force, composed of the 2nd Infantry and the 11th Armored Cavalry Squadron, prepared for the march to Thượng Ðức.
Slowly moving toward Thượng Ðức it was still 4 km east of the ARVN fire base on Hill 52, which itself was under PAVN artillery and infantry attack.
[3]: 118 On the night of 6 August the most intense PAVN bombardment of the battle began hitting Thượng Ðức with over 1,200 rounds, including many from 130mm guns, landing inside the perimeter.
The first wave of infantrymen was repulsed that night, but the assault at dawn on 7 August using 37mm anti-aircraft guns as direct fire weapons against the Rangers' positions penetrated the defense.
The low hills at the southern foot of the ridge had been seized by the PAVN 29th Regiment, which had blocked the ARVN task force's relief of the Rangers at Thượng Ðức.
To deal with the threat developing west of Da Nang, the 3rd Airborne Brigade was assigned the secondary mission of blocking the western approaches in Hieu Duc District.
The 8th and 9th Airborne Battalions began the attack and made their first firm contact with elements of the 29th Regiment on 18 August east of Hill S2, the same area in which the 3rd Division Task Force had run into strong resistance.
[3]: 121 Meanwhile, in Thua Thien Province, PAVN pressure against the lightly held Huế defenses was becoming severe, and Trưởng was receiving strongly phrased requests from his elements north of the Hải Vân Pass to return at least some of the Airborne Division.
Although heavy fighting continued in the hills and on the ridge for several more weeks as the Airborne Division expanded its control of critical terrain, the most violent phase of one of the bloodiest battles since the cease-fire was over.
The remaining 1st and 7th Battalions kept patrols there and depended on artillery fires to deny the terrain to PAVN occupation, but placed their main battle positions near Dong Lam Mountain, about 4 km to the east, and in the ridges above Hill 52.
The rainy season had reached Quảng Nam Province in October and provided some respite from the intense and continual combat of summer.
[3]: 122 [6]: 97 The Battle of Thượng Ðức was costly for both sides, despite successfully stalling the PAVN advance, the ARVN failed to recapture the town due to shortages of supplies and replacement troops.
[6]: 96 In the opinion of one ARVN commander, the PAVN goal had been to secure the left flank of I Corps to continue the building of the eastern corridor of the Ho Chi Minh Trail,[8] while another believed that had it not been for the actions of the Airborne, Da Nang would have fallen in 1974.
[9] Moreover, the ARVN had suffered irreplaceable losses among its elite forces and expended large amounts of ordinance which could not be replaced due to decreased U.S. aid.
The 304th Division was rendered combat ineffective and would play only a marginal role in the 1975 Spring Offensive, however ARVN intelligence did not appreciate the 304th's weakness and so Trưởng maintained substantial forces west of Da Nang to counter any thrust by the 304th from Thượng Ðức.