Monday, July 15, 2019

The Fire



It happened on January 27, 1967, at Pad 34 at Cape Kennedy.

Astronauts Gus Grissom, the command pilot, and Ed White and Roger Chaffee were fully suited up in the command module, performing what was known as a “plugs out test” – a full dress rehearsal for the planned February lift-off.

This command module was known as a Block I spacecraft. It was an early model command module, not intended for docking, only for orbital test missions. This specific module, Spacecraft 012, had arrived at the Kennedy Space Center five months earlier with a history of problems. Most revolved around the Environmental Control Systems. Grissom had even hung a large lemon on it while visiting the plant where it was being built.

Once the astronauts were in the module, the hatch was sealed. It could not be opened quickly or easily in an emergency. Pure oxygen at 16 PSI was pumped into the cabin. The men went through their checklists in the live module.

At 6:31 pm a spark ignited the oxygen, transforming the cabin into an inferno. Pressure quickly built and exceeded design limits, rupturing the block. Thick black smoke and flames poured out. The astronauts had no chance, succumbing to asphyxiation in seconds.

NASA and the nation were stunned and the Apollo space program ground to a complete halt in the immediate aftermath of the tragedy.

An investigation labeled the Apollo 204 Review Board convened. (NASA designated the flight as “Apollo 204”, even though Grissom, White and Chaffee were to be the Apollo 6 crew.) Astronaut Frank Borman was a member of the panel. It ultimately concluded that, while a specific source of the spark could not be determined, an electrical circuit in or near the Environmental Control Unit was the likely culprit. The pure oxygen within the cabin mixed with a preponderance of flammable material contributed to the accident, the first direct loss of life the space agency had to face.

Several recommendations followed, amounting to over 1,300 capsule design modifications:

- fireproof materials were to be used in the redesigned Block II command module
- fireproof materials were to be used in newly designed astronaut spacesuits
- all components and electrical wiring were to be carefully insulated
- a new hatch designed for quick opening replaced the old unit

  
NASA renamed the mission Apollo 1 in the spring of 1967. There were no Apollo 2 and Apollo 3 missions. The Apollo 2 capsule was dismantled during the attempt to isolate the cause of the fire. The Apollo 3 command module was scrapped in favor of the newer, redesigned capsule.

The ultimate sacrifice borne by Gus Grissom, Ed White, and Roger Chaffee was not in vain; it no doubt brought twelve men to the Moon and back safely, without any further loss of life.


No comments: