46 Years ago today, Apollo 13 exploded– the sacrifices of Apollo 1 helped them get back
The catastrophe of Apollo 1 in 1967 helped save the astronauts on Apollo 13. Of the lessons learned from that disaster hadn’t been applied, the crew of Apollo 13 would never have made it back after their in-flight explosion.
Three astronauts died on 27 January 1967 during a test on the launch pad. Fire roared through the Apollo 1 cabin, killing Gus Grissom, Ed White and Roger Chaffee in the command module.
Since the Apollo program was entering uncharted territory, just about everything that was being designed was unique, particularly the command module. When the first spaceship was delivered to the Kennedy Space Center in 1966 there were 113 significant incomplete planned engineering changes with another 623 change orders made after delivery.
It’s a miracle that with that much to be done, that the program succeeded in accomplishing the goal of putting a man on the moon.
One area that concerned the Apollo 1 crew greatly was the amount of flammable material in the command module, especially since it was going to be an oxygen-rich environment. There was a lot of nylon netting and Velcro scattered about, which was convenient for holding tools, manuals and other equipment, but rather dangerous for those inside if there was ever a fire.
The crew felt so strongly about it, they posed in a parody of their official portrait with all three heads bowed and their hands clasped in prayer. They sent the picture to their project manager saying: “It’s not that we don’t trust you, Joe (project manager). But this time we’ve decided to go over your head.”
As events would prove, their prayers were in vain.
“You sort of have to put that out of your mind,” said Gus Grissom in a December 1966 interview. “There’s always a possibility that you can have a catastrophic failure, of course; this can happen on any flight; it can happen on the last one as well as the first one. So, you just plan as best you can to take care of all these eventualities, and you get a well-trained crew and you go fly.”
This is the attitude that, overall, made the US Space Program a success and astronauts true heroes.
On 27 January 1967, the crew of Apollo 1 was going to do a ‘plugs out’ test. Where the capsule was disconnected from all outside power sources and worked on internal power alone. This test was key to make the 21 February launch date. It wasn’t considered a dangerous test because there was no fuel loaded and all pyrotechnic devices were disabled.
As soon as they were in their suits, and strapped into their seats, the first problem arose. Grissom reported a strange odor in the air in his suit. They shut down the countdown and an air sample was taken. But no cause could be found.
Later, the investigation said this odor had nothing to do with the subsequent fire. I submit it did have something to do, even if it technically didn’t. Grissom’s sixth sense was picking up something, but he, nor anyone else, could figure out what exactly was wrong. As events would prove, something was wrong.
Sixth sense is something you can’t quantify. I believe sixth sense is the power of the subconscious taking care of us. It is the subconscious picking up signals from the other five senses that we are not consciously aware of, and putting them together, subtly sending a message into our conscious to warn us. Grissom did pick something up, the smell, but you have to wonder if he really smelled something or if he was picking up other things and it manifested in the smell?
A good point man on a patrol should have excellent sixth sense. His eyes might notice something — a broken twig, a trip wire — that his mind does not really ‘see’. i.e. consciously process. The subconscious though, processes this information and sends a warning to the conscious mind in the form of the emotion of fear.
Unfortunately, not finding any problems, the countdown was resumed. While this was happening, the hatch was installed. Here was another problem: the hatch consisted of three parts: a removable inner hatch, an outer hatch that was hinged, and an outer shell hatch to protect the capsule from heat during launch and in case of an abort.
When the inner two hatches were sealed, the cabin was filled with pure oxygen at a pressure slightly higher than atmospheric pressure. An issue with the hatches is that the inner hatch opened inward because of the overpressure inside. This meant it would be very hard to remove from the interior in an emergency.
More problems developed during the test.
An alarm went off when oxygen to the spacesuits went too high.
Grissom’s mike got stuck in the transmit mode. Grissom grew more and more frustrated with the entire exercise: “How are we going to get to the Moon if we can’t talk between three buildings?”
They continued to work through the problems. At 6:30, a voltage jolt was recorded. Ten seconds later Chaffee exclaimed “Hey!” and White announced “I’ve got a fire in the cockpit!”
Because the cabin was filled with pure oxygen, it burned fast. 17 seconds after the first report of fire, there was a scream and then all transmission ceased. The capsule itself ruptured due to the fire.
It took five minutes to get through the three hatches to the men inside. At the same time, there was fear the capsule would explode and/or the fire might ignite the solid fuel rockets in the launch escape tower.
Once inside, they found the astronauts.
It took over 90 minutes to remove the bodies due to the large amount of melted nylon that fused them to the capsule.
The cause of the fire was never exactly pinned down but NASA did finally understand that everything inside a capsule pumped full of almost pure oxygen needed to be protected better, especially wiring. They found over 34 square feet of Velcro and 70 pounds of other flammable material in the small space.
In retrospect, NASA realized they had never run a fire test on the command module prior to testing it with people inside. They also realized having a higher pressure inside made removal of the inner hatch impossible.
As a result of the Apollo 1 fire and the sacrifice of three brave men, NASA fire-proofed all future Apollo capsules with non-flammable materials, switched the atmosphere to a less flammable nitrogen-oxygen mix, and made sure all electrical connections were specially coated.
While an electrical arc did cause the Apollo 13 explosion, it was inside a tank subcontracted outside of NASA. Senior engineers, after Apollo 13 made it back, said that if the capsule hadn’t been upgraded with all these fire-proof changes, it very likely would have burned up on re-entry, especially since water droplets which condensed from the astronaut’s breathing got into almost every thing and would have caused arcs.
This is one of the events covered in more detail in Shit Doesn’t Just Happen: The Gift of Failure I.
Originally published at www.writeitforward.com on April 13, 2016.