The exhaustive investigation of the fire and extensive reworking of the CMs postponed any manned launch until NASA officials cleared the CM for manned flight. Saturn 1B schedules were suspended for nearly a year, and the launch vehicle that finally bore the designation AS-204 carried a Lunar Module (LM) as the payload, not the Apollo CM. The missions of AS-201 and AS-202 with Apollo spacecraft aboard had been unofficially known as Apollo 1 and Apollo 2 missions (AS-203 carried only the aerodynamic nose cone). In the spring of 1967, NASA's Associate Administrator for Manned Space Flight, Dr. George E. Mueller, announced that the mission originally scheduled for Grissom, White and Chaffee would be known as Apollo 1, and said that the first Saturn V launch, scheduled for November 1967, would be known as Apollo 4. No missions or flights were ever designated Apollo 2 and 3.
After delays caused by the Apollo/Saturn 204 (Apollo 1) fire, facing budgetary cutbacks, and racing with President Kennedys goal to reach the moon before the end of the decade, George Mueller, Director of the Office of Manned Space Flight, suggested testing the first Saturn V rockets with all live stages and a complete spacecraft. In the past, rockets were tested one major component and one stage at time. After these initial tests were completed successfully, a full test of a complete vehicle would be conducted. At first, this unusual proposal from George, called "all-up" testing, met with resistance.
Apollo 4 had four major goals:
- Demonstrate structural and thermal integrity and compatibility of launch vehicle and spacecraft; confirm launch loads and dynamic characteristics.
- Verify operation of command module heatshield (adequacy of Block II design for reentry at lunar return conditions), service propulsion system (SPS; including no ullage start), and selective subsystems.
- Evaluate performance of emergency detection system in open-loop configuration.
- Demonstrate mission support facilities and operations needed for launch, mission conduct, and CM recovery.
During the third orbit and after SPS engine burn, the spacecraft coasted to a simulated translunar trajectory, reaching an altitude of 18,079 kilometers. The launch marked the initial flight testing of the S-IC and S-II stages. The first stage, S-IC, performed accurately with the center F-1 engine cutting off at 135.5 seconds and the outboard engines cutting off at LOX (Liquid Oxygen) depletion at 150.8 seconds when the vehicle was traveling at 9660 km/h at an altitude of 61.6 km. Stage separation occurred only 1.2 seconds off the predicted time. Cutoff of the S-II occurred at 519.8 seconds.
A Pacific Ocean landing was planned and accomplished on November 9, 1967, 03:37 p.m. EST, just eight hours and thirty-seven minutes and fifty-nine seconds after takeoff. The Apollo 4 Spacecraft 017 splashed down at 30 deg 06 min North and 172 deg 32 min West. It missed the planned impact point by only 16km. The capsule was recovered by USS Bennington CVS-20.
The Apollo 4 mission was a success, all mission objectives achieved. With the success of this first "all up" test, George Mueller's decision was vindicated. This new method of all up testing allowed NASA to meet the 1969 lunar goal, despite the setback of the Apollo 1 fire, while saving money and equipment for later use.