NASA prepared the Apollo Command Module with a number of tools for extended survival if a crew landed way off-course from the planned recovery area.

Apollo’s early design was to have the CM parachute to a land recovery. Cooler heads and design limits rethought that idea and returned to water landings. For one, the CM was becoming heavier than planned, increasing the chances of serious damage to the CM on landing and, in turn, to the crew inside.

The early heat shield bracing structure was initially built too weak even for a water landing. In one water drop test, a CM test module’s heat shield collapsed, and the first and only CM submersible was born. With egg on their face, North American Rockwell modified that design. (The video below starts at coverage of that water drop test.)

We know of the Fire on January 27, 1967 that took the lives of the Apollo 1 crew. Among the many improvements to the Block II CM used for manned flights was the outward-opening crew hatch.

On water landing, the CM could be floating apex up (tunnel side to the sky, or “Stable one”) or apex down (tunnel side underwater, or “Stable two”). Three balloons would inflate on splashdown to upright the spacecraft since stable-two would leave the hatch underwater.

NASA learned several lessons from the problematic splashdown recoveries of Aurora 7 and Gemini 8. Apollo crews had enough resources to be safe on its own for at least 48 hours.

On landing, if the crew had little to no communication with recovery forces, they could eject a green dye marker to help overhead searches find them in the water.

CM postlanding ventilation
These vents didn’t look particularly inviting to use. (NASA)

Normal procedure also initiated the opening of the post-landing ventilation duct system. This opened a vent that would push fresh air into the spacecraft. The air supply could be directed using three tubes connected to each crewmember’s faces. In practice, some crews found the vent problematic. Apollo 11’s crew considered that venting their atmosphere to earth’s own could’ve been a lunar contamination risk, however remote. Apollo 12 had to switch their vent open or closed as high seas kept spilling water through it.

If the crew landed in a darkened area, they could also activate a recovery beacon that could flash once every 4 seconds for normal acquisition, or as fast as twice per second. Naturally, the low-flash speed would be used to keep it running for as long as possible, or about 24 hours.

CM Sea Anchor
The sea anchor, dropped to slow down the CM’s drift while recovery crews caught up. (NASA)

A luckier crew that’s sighted by recovery but landed too far for helicopter crews to reach them get a sea anchor thrown a little downrange from the CM’s drift path. The crew would deploy a snagging line hook to eventually grab the sea anchor to slow their drift so that crews don’t fight the currents in getting to the spacecraft.

A Longer Stay

So, let’s say your CM dropped in the middle of nowhere. Apollo 13 had to entertain the possibility of landing in the Atlantic Ocean, where no recovery forces existed. If that happened, the crew needed to crack out their survival gear, located in two rucksacks.

CM sea water pump
The sea water pump and its operation. (NASA)

After the recovery beacon is deployed, the crew might activate a sea water pump if their two other drinking water sources were exhausted or malfunctioning. The crew deploys a hose into the water outside from a vent that normally was a steam exhaust during the mission. A hand-operated bellow pulled the seawater into the spacecraft through the vent, where the astronauts can collect the water in a bag. After a desalination chemical from their survival kit, the water became drinkable.

CM survival kit

The survival kit also had these goodies:

  • A beacon/radio, preset to a specific recovery frequency. It was waterproof and could survive accidental submersion.
  • Simple sunglasses.
  • Three bottles of sun-resistant lotion.
  • The desalination kits and extra tablets.
  • A three-man covered life raft with sunbonnets. The crew could sit inside the raft, fully covered from excessive ocean spray or sunlight, since eventually the Command Module would have no environmental control to speak of, and staying inside the powerless spacecraft would not only be uncomfortable but potentially dangerous and nauseous.
  • An additional dye marker and sea anchor was included as bailing out of the CM might also mean that the crew can’t stay by the spacecraft.
  • A couple of machetes that double as saws. A really off-course crew might have splashed down near land or landed on soil.
  • Three water bottles, each filled with 80 ounces of water.
  • Three waterproof multi-use survival lights with features that would make the Swiss Army proud.
    • A light with a steady or strobing action
    • A signalling mirror
    • A compartment containing
      • fishing line and hook
      • A fire starter kit
      • needle and thread
      • whistle
      • compass

The only thing missing from the survival kit was food. The crew would likely have extra meals from the mission they could scavenge from the CM.

And then there was survival training. Lots and lots of it, for both desert and tropical, given that the crew’s return path could drop them anywhere near islands of various sizes.

Frank Borman, Neil Armstrong, John Young and Deke Slayton, wearing parachute material as makeshift clothing in desert survival training. (NASA)

It didn’t hurt NASA that most of the astronauts had survival training prior to their tenure at the space agency, given that many were test pilots or military personnel.

Happily, no Apollo crew had to break out their survival gear.

(Source: Apollo Operations Handbook, Block II Command Module)