While his squadron’s support of the 1st ARVN Division’s ongoing drive near the Laotian border continued, Lieutenant Colonel Leu committed 21 UH-34Ds to support the offensive against the Do Xa base area along the southern edge of I Corps. On 27 April, Marine crews helilifted over 567 troops of the 2d ARVN Division into the mountainous area roughly 22 miles southwest of Tam Ky to begin Operation BACH PHUONG XI. The squadron was less fortunate during this operation than it was during the lengthy Quang Tri effort. One helicopter was shot down by Viet Cong fire which wounded the pilot, Captain Virgil R. Hughes, in the leg. The crew and the embarked ARVN soldiers escaped further injury when the aircraft made a crash landing in which it suffered extensive damage. After the crew was rescued, a salvage team from Da Nang stripped the helicopter of all usable parts and burned the hulk so the Viet Cong could not make use of it. This was the first Marine helicopter loss definitely attributed to direct enemy action.[9-3] Following the initial heliborne assaults into the Do Xa area, two UH-34Ds were rotated to Tra My from Da Nang on a daily basis. Refueling from the TAFDS bladder, these standby aircraft were used primarily to perform medical evacuation missions for VNMC and ARVN units involved in BACH PHOUNG XI. Before the operation ended in mid-May, HMM-162’s crews had evacuated nearly 100 Marine and ARVN casualties from hazardous landing zones scattered along the border of I and II Corps. The task element’s O-1Bs also provided aerial reconnaissance support for all phases of the operation. On 19 May, the day before BACH PHOUNG XI terminated, 12 Marine UH-34Ds lifted the two Vietnamese Marine battalions to the provisional brigade command post at Tra My. This particular phase of the operation evoked favorable comment from an anonymous U.S. Marine pilot who noted on an unsigned debriefing form that the heliborne withdrawal had gone smoothly and that the Vietnamese Marines appeared “well organized in the landing zones and at Tra My.”[9-4] BACH PHOUNG XI ended unceremoniously the following day when HMM-162 helilifted the ARVN battalions from the Do Xa base area. One trend which became increasingly apparent as the spring of 1963 unfolded was the growing utilization of the Army UH-1B helicopter gunships as escorts to and from landing zones. The gunships accompanied all Marine assault helilifts and medical evacuations, and when available, also escorted resupply flights in order to provide suppressive fire around government positions while landings were in progress. Although well suited for the escort missions, the lightly armed UH-1Bs did not replace the Vietnamese Air Force attack aircraft as the principal source of preparatory air strikes around landing zones being used for assault helilifts. The Marines continued to rely on the more heavily armed VNAF T-28s and A-1Hs to conduct the so-called “prep strikes.”[9-A]