Apollo 1
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Apollo One is the name given to the AS-204 spacecraft after it was destroyed by fire during a training exercise on January 27, 1967, at Pad 34 atop a Saturn IB rocket. Its crew were the astronauts selected for the initial Apollo program mission: Mission Commander Virgil Grissom, Command Module Pilot Edward White, and Lunar Module Pilot Roger Chaffee.
Immediately prior to the accident, the crew were reclining in their horizontal couches, running through a checklist of things they would do in space while a communication system problem was being fixed. Suddenly, a voice (now believed to be Chaffee's, as his was the only clear channel) crackled over the COM link, "Fire, I smell fire." The transmission ended with a cry of pain. The crew could not escape because the hatch opened inward, requiring that the cabin be depressurized. At best, the hatch would have taken 90 seconds to open, while the crew were killed in only about 15 seconds.
The fire is believed to have been caused by a spark somewhere in 30 miles (50 km) of wiring, leading to rapid combustion in the pressurized oxygen atmosphere. The Apollo 204 Review Board determined that a copper wire running through an environmental control unit near the command module pilot's couch had become stripped of its insulation and abraded by repeated opening and closing of an associated access door. This weak point in the wiring also happend to pass near a junction in a glycol cooling line, which had developed a leak and was expelling glycol vapor fumes, which were highly flammable.
The fire spread quickly, melting through the astronauts' space suits. Grissom's and White's suits were later found to have fused together. It was confirmed that the crew had died of smoke inhalation rather than burns. The company that produced the command module, North American Aviation had originally suggested that the hatch open outward, and be able to open with explosive bolts in case of emergency. They had also suggested that the atmosphere be an oxygen/nitrogen mixture, like the air around us. NASA didn't agree, arguing that the hatch could be accidentally opened, and that if too much nitrogen were released into the atmosphere, the astronauts would pass out and then die. They also argued that since a pure oxygen atmosphere was used safely in Mercury and Gemini, it should be safe to use for Apollo. After the fire, Apollo was grounded pending a redesign, with the following results:
- The atmosphere would not be pressurized to two lb/in² (14 kPa) above atmospheric pressure
- The hatch would open outward, and more quickly
- Flammable materials were replaced with self extingishing materials
- Plumbing and wiring were covered with protective insulation
- 1,407 wiring problems were corrected
When North American Aviation shipped Spacecraft CM-012 to Kennedy Space Center, it bore a banner proclaiming it "Apollo One" and Grissom's crew had received approval for an "Apollo 1" patch in June 1966, but NASA was planning to call that mission "AS-204." After the fire, the astronauts' widows asked that "Apollo 1" be reserved for the flight their husbands would never make. For a time, mission planners called the next scheduled launch "Apollo 2." Suggestions were made that the flights should be called "Apollo 1" (AS-204), "Apollo 1A" (AS-201), "Apollo 2" (AS-202), and "Apollo 3" (AS-203). Finally, the NASA Project Designation Committee approved "Apollo 4" for the first (unmanned) Apollo-Saturn V mission (AS-501), but declared that there would be no retroactive renaming of AS-201, -202, or -203. The Apollo 1, (AS-204) Saturn IB rocket was later used to launch the Apollo 5, earth orbit Lunar Module test mission. Apollo 1 mass 20,412 kg.
| Preceded by : Gemini 12 |
Apollo program | Followed by : Apollo 4 |