movement on foot, from an area from Hill 937, and both Conmy and Honeycutt expected the 1/506th to be ready to provide support no later than the morning of 15 May. Although Company B seized Hill 916 on 15 May, it was not until 19 May that the 3/187th as a whole was in position to conduct a final assault, primarily because of nearly impenetrable jungle. The 3/187th conducted multi-company assaults on 14 May, incurring heavy casualties, while the 1/506th, led by 1st. Lt. Roger Leasure, made probing attacks on the south slopes of the mountain on 16 and 17 May. The difficult terrain and well organized PAVN forces continually disrupted the tempo of the US tactical operations on Hills 916, 900, and 937. Steep gradients and dense vegetation provided few natural landing zones (LZs) in the vicinity of the mountain and made helicopter redeployments impractical. The terrain also masked the positions of the PAVN 29th Regiment, making it nearly impossible to suppress anti-aircraft fire, while the jungle covered the movement of PAVN units so completely that it created a nonlinear battlefield. PAVN soldiers, able to maneuver freely around the LZs, shot down or damaged numerous helicopters with small arms fire, Rocket-propelled grenades, and crew-served weapons. The PAVN also assaulted nearby logistical support LZs and command posts at least four times, forcing deployment of units for security that might otherwise have been employed in assaults. Attacking companies had to provide for 360-degree security as they maneuvered, since the terrain largely prevented them from mutually supporting one another. PAVN platoon- and company-sized elements repeatedly struck maneuvering US forces from the flanks and rear. Tactical difficulties The effectiveness of US maneuver forces was limited by narrow trails that funneled attacking companies into squad or platoon points of attack, where they encountered PAVN platoons and companies with prepared fields of fire. With most small arms engagements thus conducted at close range, US fire support was also severely restricted. Units frequently pulled back and called in artillery fire, close air support, and aerial rocket artillery, but the PAVN bunkers were well-sited and constructed with overhead cover to withstand bombardment. During the course of the battle the foliage was eventually stripped away and the bunkers exposed, but they were so numerous and well constructed that many could not be destroyed by indirect fire. Napalm, recoilless rifle fire, and dogged squad and platoon-level actions eventually accounted