— No one saw it begin. No one knew then, or ever, just when it came to life.
The catastrophe that was to engulf Apollo 1 at T-minus-10 minutes and holding actually began building hours earlier. A technician on the gantry reviewed his checklist of procedures and timelines. The hatch was sealed, the astronauts were secured in their couches, the spacecraft was powered up. Internal cabin pressure began rising for the tight seal required for the “contamination-free” environment.
Valves opened. Pure oxygen flowed into the cabin. The pressure went through changes. Ambient air of 21 percent oxygen, nearly 79 percent nitrogen, and a smattering of other normal atmospheric gases were flushed from the three-man-cabin. Sensors confirmed the desired reading of 16.7 pounds per square inch of 100 percent oxygen. And the cabin, its equipment, wiring, plastic, Velcro fabric, suits, instruments, anything and everything was soaked in pure oxygen.
If everything had functioned perfectly, the tragic events that overtook Spacecraft 012 might never have happened. But this was a ship beset by problems. It couldn’t even communicate properly with a blockhouse 1,600 feet away.
This was the spacecraft that an Apollo quality-control inspector, Thomas Baron, had condemned as “sloppy and unsafe,” the ship that spacecraft manager Joe Shea admitted had been plagued with more than 20,000 failures in its construction and assembly. This was the same craft that John Shinkle, Apollo program manager, castigated as missing at least "half the damn engineering work" that had been listed as completed, and that Rocco Petrone, director of launch operations, railed against as a totally unacceptable "bucket of bolts."
This was the spacecraft that had been filled with a thick soup of 100 percent oxygen.
Pure oxygen is one of the most dangerous and corrosive gases known. In a short time it can corrode and transform iron and other metals into flaky garbage. As a fire’s oxidizer, in its pure form, it fans flames at their most rapid pace. But it had been used in the Mercury and Gemini spacecraft without trouble, and NASA engineers had become complacent about the possibility of a fire.
For more than five hours, the oxygen in the pressurized cabin of 012 permeated the surface of everything in the cabin, everything from plastic to paper checklists, to non-metallic insulation, to aluminum and fabric. Everything. Pure oxygen ate into the material and squeezed under the surface layers of materials.
Below the couch on which Gus Grissom lay ran bundles of wires. All kinds of wires performing all kinds of tasks. Some carried electrical current to different operating systems of 012. Others were hooked to the suits of the astronauts for medical monitoring and communications. The wires had not been brought together in sealed and protected tubing, but had been laced together with plastic and other strapping. The wire was in lousy shape. It had been moved, shaken, pushed, shoved, squeezed, stepped on, and in some cases had lost its outer insulation to constant rubbing and friction. It was a mess.
Somewhere beneath the seat of the commander of Apollo 1, an open wire chafed. Insulation was torn. The wire, charged with electrical power, lay bare.
The spark exploded. In an instant faster than thought, the tiny flicker of electricity became a massive shock wave of flame, which fed on the oxygen-soaked environment of the pressurized spacecraft interior.
On the medical monitors, Ed White’s pulse rate leapt crazily upward. The gauges showed sudden bursts of movement by the three men.
A single word from Ed White, followed immediately by the deep voice of Gus Grissom.
"We’ve got a fire in the cockpit!"
Then a garbled transmission and the final plea:
"Get us out!"
Another transmission, words no one would ever understand, and ...