Explorer II was a manned U.S. high-altitude balloon that was launched on November 11, 1935, and reached a record altitude of . Launched at 8:00 am from the Stratobowl in South Dakota, the helium balloon carried a two-man crew consisting of U. S. Army Air Corps Captains Albert W. Stevens and Orvil A. Anderson inside a sealed, spherical cabin. The crew landed safely near White Lake, South Dakota, at 4:13 pm and both were acclaimed as national heroes. Scientific instruments carried on the gondola returned useful information about the stratosphere. The mission was funded by the membership of the National Geographic Society. Background In January 1934, the National Geographic Society (NGS) and the U. S. Army Air Corps decided to collaborate on a program to build and launch a manned balloon to the then record altitude of . This vehicle would be capable of carrying a crew of three in an airtight capsule, along with a laboratory of instruments. The hydrogen balloon, named Explorer, was completed by July at a cost of around $60,000; currency. The balloon was launched from a canyon in the Black Hills of South Dakota—dubbed the Stratobowl—on July 28, 1934 and reached a near-record altitude of before tears in the fabric led the crew to begin reducing their altitude. A rupture in the balloon resulted in a precipitous descent, followed by a spark that caused the hydrogen to ignite and destroy what was left of the balloon, leaving the capsule to plummet toward the ground at terminal velocity. The crew just managed to escape using their parachutes, with the last man bailing out at above the ground. Their capsule was almost completely destroyed upon impact. The crash resulted in a national embarrassment, leading Captain Albert W. Stevens, the scientific observer on board the Explorer balloon, to lobby for another attempt with an improved balloon to be named Explorer II. But news of the fatal crash of a Russian stratospheric attempt in 1934 left President Gilbert H. Grosvenor of the NGS sobered by the risk. A review of the crash by the National Bureau of Standards (NBS) was held between July and September, revealing that the balloon had not opened symmetrically during the ascent, causing stresses that led to the fabric tears. A month-long delay prior to launch had allowed the rubberized cotton to stick together, which created the uneven expansion. The hydrogen explosion followed when the