What happened on Apollo 1?

A test on the ground

The mission, then known as AS-204, was to be the first crewed Apollo flight, an Earth-orbit test planned for February 1967. On January 27 the crew rehearsed the countdown inside the command module on top of an unfueled Saturn IB rocket at Launch Complex 34, with the spacecraft switched to its own power, a so-called plugs-out test. Nothing in it was meant to be dangerous.

The three men were experienced. Gus Grissom had been the second American in space, in 1961, and had commanded Gemini 3. Ed White had made America’s first spacewalk in June 1965. Roger Chaffee, 31, a Navy pilot, was preparing for his first flight. The test had dragged on for hours, slowed by problems with the radio links. At 6:31 in the evening a fire started near the floor of the cabin. The hatch opened inward, and the pressure inside held it shut. All three died before the pad crew could get it open.

What the review board found

NASA’s Apollo 204 Review Board, chaired by Floyd Thompson, director of the Langley Research Center, reported in April 1967. It found no single cause, but a set of conditions that together made the fire possible:

• The atmosphere: pure oxygen, at a pressure a little above sea level, in which materials that would smolder in air burn quickly.
• The fuel: flammable materials inside the cabin, such as nylon netting and Velcro.
• The spark: most likely an electrical arc from damaged wiring.
• The hatch: a design that opened inward and took well over a minute to open even in practice.

The fix

NASA rebuilt the command module. The new hatch opened outward, in seconds. Flammable materials were replaced with fire-resistant ones, the wiring was protected, and on the launch pad the cabin now held a mix of 60% oxygen and 40% nitrogen instead of pure oxygen. At the request of the crew’s widows, the mission was renamed Apollo 1. No Apollo carried a crew for twenty months, until Apollo 7 flew on October 11, 1968. Two months after that, Apollo 8 was orbiting the Moon.

Moscow’s losses

The Soviet program was burying its own. Its chief designer, Sergei Korolev, had died after surgery in January 1966. On April 24, 1967, Vladimir Komarov died when the parachute of Soyuz 1 failed on the way home, the first person to die during a space flight. Yuri Gagarin had been his backup. And in 1986 the Soviet press revealed a death kept secret for 25 years: on March 23, 1961, a young cosmonaut trainee, Valentin Bondarenko, had died after a fire in an oxygen-rich test chamber.

How they are remembered

Grissom and Chaffee are buried at Arlington National Cemetery, White at West Point. Launch Complex 34 is empty today except for the concrete pedestal, and a plaque there reads: “Ad astra per aspera. A rough road leads to the stars.” In July 1969 the crew of Apollo 11 left an Apollo 1 mission patch on the Moon, together with Soviet medals for Gagarin and Komarov, on the same moonwalk that began with Armstrong’s famous words. NASA still honors its fallen astronauts each year in late January, close to the anniversary of the fire.