Helicopter evacuation saved the lives of other Marines. The doctors credited the flying skills and bravery of the evacuation pilots for these rescues. Immediate response to day and night calls was instrumental in the recovery of numerous Marines. Rear Admiral Lamont Pugh, Surgeon General of the U.S. Navy, commented upon the value of the helicopter and on other reasons for success of medical support. After a Far East inspection trip, which included a visit to the 1st Marine Division during the battle of Bunker Hill, Admiral Pugh expressed the following opinion: ... [I] attributed the new low record “2% mortality” of those men wounded in action to the bullet resistant vest, to skillful frontline surgery with availability of whole blood, the utilization of helicopters for casualty evacuation direct to hospital ships and rear area hospitals, and the efficient manner in which the Hospital Corpsmen of the Navy fulfilled their mission with the Marines.[198] [198] _PacFlt EvalRpt_ No. 5, Chap. 12. p. 12-8. In another logistical area, the performance was not quite as satisfactory, for the level of supply of one important item--illuminating shells--fell dangerously low during the Bunker fighting. On 16 August, 3/1 reported early in the morning that “artillery illumination was exhausted and 81mm mortar illumination was fast diminishing.”[199] To replace the shell-produced light, the regiment used a flare plane.[200] [199] 3/1 ComdD, Aug 52, p. 4. [200] Earlier, on 13 August, a flare drop requested by the 1st Marines went awry when the aircraft got off course and dropped the flares forward of the 5th Marines main line. 1stMarDiv G-3 Jnl, 13 Aug 52. Ammunition supply appeared to be no problem to the Chinese. The rate and frequency of mortar and artillery fire proved that the enemy had a vast store of these shells. During the heavy fighting, the division observed that the enemy expended approximately 17,000 mortar and artillery rounds in the 11–16 August period of the battle. It was noted for the first time that the Chinese used mortars primarily in support of limited attacks. About the enemy’s reliance on mortars and the technique of their employment, the 1st Marine Division reported: