Space Rocket History #126 – Apollo-Saturn IB: AS-201, AS-202, and AS-203

Video from the channel Space Rocket History about AS-202, linked on its Above Ten Thousand entry. Duration: 31:47. Language: English. Video type: Documentary.

Episode 126 of the Space Rocket History podcast, hosted by Michael Annis and dedicated to the first three Saturn IB flights of the Apollo program: AS-201, AS-203 and AS-202, in the order they were launched. The narration is combined with period NASA audio clips.

The Saturn IB was the improved version of the Saturn I, with eight H-1 engines in the first stage and the liquid-hydrogen S-IVB stage, powered by a J-2 engine that would also be used on the Saturn V. These flights tested, uncrewed, the launch vehicle, the instrument unit and the Block I Apollo spacecraft. AS-201 lifted off on February 26, 1966 from Complex 34 with spacecraft 009. The suborbital flight lasted 37 minutes, and the capsule landed far from the planned point in the South Atlantic, where it was recovered by the USS Boxer. There were three serious failures: a pressure drop in the service module engine caused by helium ingestion, loss of roll control during reentry due to an electrical fault, and distorted measurements caused by a short circuit. To save time, NASA moved AS-203 ahead, which flew without a spacecraft. On July 5, 1966, it placed the S-IVB into orbit from Pad 37B to study, with sensors and television cameras, how hydrogen behaved in weightlessness. It validated the restart capability planned for the Saturn V, although the stage was destroyed in a final pressurization test.

AS-202 lifted off on August 25, 1966 from Pad 34 with spacecraft 011, the first to fly with the guidance and navigation system and with fuel cells. The service module engine fired four times, two of them brief, to test rapid reignition. The command module entered the atmosphere at 8,690 m/s and performed a skip reentry: it dropped to 67 km and climbed back to 81 km before the final descent. The main parachute opened at 7,250 m. It splashed down near Wake Island, 380 km from the planned point, and the USS Hornet took eight and a half hours to arrive. The heat shield and the capsule withstood reentry well.