The first raid to use these new techniques was on the night of 9–10 March against Tokyo. Another wing—the 314th Bombardment Wing (19th, 29th, 39th, and 330th BG) commanded by Brig. Gen. Thomas S. Power—had arrived in the Marianas and was stationed at North Field on Guam. A total of 302 B-29s participated in the raid, with 279 arriving over the target. The raid was led by special pathfinder crews who marked central aiming points. It lasted for two hours. The raid was a success beyond General LeMay's wildest expectations. The individual fires caused by the bombs joined to create a general conflagration due to strong winds of some 17 to 28 mph (27 to 45 km/h) at ground level, that prevented a more specific firestorm event. When it was over, sixteen square miles (41 km2.) of the center of Tokyo had gone up in flames and nearly 84,000 people had been killed. Fourteen B-29s were lost. The B-29 was finally beginning to have an effect.