ECN-792 Viewed from the front the #1 XB-70A 62-0001 is shown climbing out during take-off. Most flights were scheduled during the morning hours to take advantage of the cooler ambient air temperatures for improved propulsion efficiencies. The wing tips are extended straight out to provide a maximum lifting wing surface.The XB-70A, capable of flying three times the speed of sound, was the world's largest experimental aircraft in the 1960s. Two XB-70A aircraft were built. Ship #1 was flown by NASA in a high speed flight research program. August 17,1965 NASA Photo