Acting as executive agent for the Joint Chiefs, Arnold named himself the Twentieth's commander, and the AAF Air Staff as also the Air Staff of the Twentieth Air Force. Brig. Gen. Haywood S. Hansell served as chief of staff and "de facto" commander of the Twentieth after Arnold suffered a heart attack in May. Centralized control of the Superfortresses from Washington marked the recognition of the B-29 as a strategic weapon that transcended theaters and services. That same month, the first Superfortresses arrived in India, having flown across the Atlantic Ocean using the South Atlantic Transport route from Morrison Field, Florida to Natal, Brazil then across to North Africa, then to Arabia, and Persia. Accompanying them was Major General Kenneth B. Wolfe, the designated commander of the XX Bomber Command, which had been reassigned from the Second Air Force as the operational component of the Twentieth Air Force. Although a brilliant officer in research and development, with an excellent knowledge of the B-29, Wolfe had no upper echelon command or operational experience and was thus an unfortunate choice to command the first B-29 operations. The 58th Bomb Wing headquarters also arrived in India during the spring of 1944.