submarine. Two days later, another squadron B-18A sighted a completely surfaced submarine at a distance of five miles from an altitude of 1,800 feet. Three depth charges were released, the third of which caused the sub to list away from the attack, side-slipping into the water. A fourth depth charge was believed to have hit the stern, then about 20 feet below the surface. The results of these attacks, however, were never confirmed. Army Air Force School of Applied Tactics The 9th Bomb Group and its squadrons were withdrawn from Trinidad, and returned without personnel or equipment to the United States in late August 1942, where all were reconstituted as part of the Air University Army Air Force School of Applied Tactics (AAFSAT) at Orlando Army Air Base, Florida. AAFSAT operated a combat simulation facility in Florida. Units and airfields were established throughout an 8,000-square-mile (21,000 km2) area of central and north central Florida designated a mock "war theater," stretching roughly from Tampa to Titusville and from Starke to Apalachicola in which war games were conducted using numerous military airfields. The 1st was equipped with a mixture of medium and heavy bombers. The squadron operated primarily from Brooksville Army Airfield which runways could better accommodate the heavy bombers. Its squadrons trained bomber crews in organization and operations, performed bombing pattern tests, experimented with tactical formations to attack moving ships, and performed equipment tests. The squadron also flew in maneuvers and took part in many experiments at Eglin Field, Florida. During this period, the 1st BS had twelve B-17 Flying Fortresses, two B-25 Mitchells and two L-3Cs observation aircraft assigned. Twentieth Air Force The training mission of the 9th Bomb Group at AAFSAT was replaced by the 903d Army Air Forces Base Unit on 1 March 1944 with "Section D", the bombardment training in an administrative reorganization. As a result, the 1st Bomb Squadron was moved without aircraft or personnel to Dalhart Army Airfield, Texas. On 28 March, it was re-designated the 1st Bombardment Squadron (Very Heavy) and began to organization process for training as a B-29 Superfortress squadron. During April the key personnel of the new squadron assembled at Dalhart, forming the command cadre, and were transferred with the group to McCook Army Airfield, Nebraska. After a brief period establishing the unit at McCook, the cadre of group and squadron operations staffs went by train to AAFSAT in May for