Although Apollo 9 did not travel to the Moon, it still had a very important role to play in the lead up to the first lunar landing. It was referred to by Chris Kraft, one of NASA’s most senior managers at the time, as by far and away the most complicated flight ever attempted by the agency to that point.
The astronauts selected to fly the mission – Jim McDivitt, Dave Scott and Rusty Schweickart – were described by historians Francis French and Colin Burgess as one of the best trained crews NASA ever assembled, having worked together since very early 1966.
Getting to be the first people to test the LM was such a plum assignment that they even turned down the opportunity to fly to the Moon with Apollo 8 (which wouldn’t have a LM with it because of delays in its construction).
Occurring between 3 – 13 March 1969, it completed ten ‘firsts’ for the Apollo programme, the most significant being the first flight of the lunar module (the spacecraft that would later land astronauts on the Moon) with people onboard.
1. First Apollo crew to name their spacecraft
Because Apollo 9 was the first flight of the programme to have more than one spacecraft involved, it was a necessity for them to have separate names to make it clear who Mission Control was trying to address over the radio. Having both being called ‘Apollo 9’ would only confuse things.
It was left up to the crew to come up with the names and they did so rather literally. They settled on ‘Gumdrop’ for their command module and ‘Spider’ for their lunar module because, well, that’s what they vaguely looked like.
2. First launch of every component needed for a moon landing
Apollo 9 marked the first time that the command and service modules, lunar module and astronauts had been launched as part of the same mission.
The Saturn V rocket had launched three times before (but with a crew onboard only once before), the command and service modules four times (twice with a crew onboard), and the lunar module once (without a crew), but never all in one go.
3. First docking and extraction of a lunar module
To protect it during launch, the flimsy and delicate Spider was stored inside the Saturn V’s third stage beneath Gumdrop. To dock with it, Command Module Pilot Dave Scott separated Gumdrop from the rocket and moved a safe distance away before making a 180° turn so that the two machines were pointing nose-to-nose. He then moved back in, docked and, after a check-out by the crew, used Gumdrop’s thrusters to pull Spider free of its nest.
4. First test of the Portable Life Support System (PLSS)
This test – and indeed the rest of the flight plan – was nearly derailed when Schweickart fell ill on the third day of the mission and threw up several times. He was supposed to conduct an EVA (spacewalk) to evaluate a new life support backpack that would later be used by astronauts walking on the Moon, but McDivitt (the mission’s commander) wasn’t willing to risk putting him in a spacesuit if it looked like he would be sick again. He called the EVA off.
However, by the fourth day of the mission Schweickart was feeling better and permission was given for him to conduct his spacewalk.
5. First American two-person spacewalk
As Schweickart tested the PLSS backpack, Scott was asked to take pictures of him. It made it the first time for NASA that more than one astronaut was outside the confines of their spacecraft at the same time. The first ever two-person spacewalk had been conducted by the Soviet Union just two months before Apollo 9.
6. First undocking of the lunar module and command module.
Aside from being used by astronauts on the Moon, the PLSS backpack would also be needed if the LM and command module couldn’t re-dock due to a mechanical issue. It would allow the two astronauts in the LM to do a spacewalk over to the safety of the command module. Now that Schweickart had tested it and proved it to be operational, Spider and Gumdrop could separate.
7. First flight of a lunar module with astronauts onboard.
The undocking took place on the fifth day of the mission. Over the course of several hours, McDivitt and Schweickart fired the LM’s descent engine multiple times to make adjustments to their orbit around Earth and moved to over 100 miles away from Scott in Gumdrop to test out its systems.
8. First astronauts to fly in space in a craft they couldn’t return to Earth in.
The LM was the first (and so far only ever) US spacecraft designed to carry humans that did not have a heatshield. It would have added too much weight. Without one, the LM had no way to make a survivable re-entry through Earth’s atmosphere.
McDivitt and Schweickart therefore had to count on being able to get back to Scott in Gumdrop to come back home alive.
9. First astronaut to fly the command module on their own.
During Apollo 7 and Apollo 8, the job of keeping the command module ticking along had effectively been conducted by all three astronauts on the crew. After Spider undocked with McDivitt and Schweickart inside during Apollo 9, that job fell to just Scott. It made him the first astronaut to fly in space on his own since Gordo Cooper closed out Project Mercury in 1963.
10. First docking of two crewed American spacecraft.
As commander, McDivitt was the one who had to conduct the re-docking between Spider and Gumdrop. During his career as a pilot he had been used to having to look straight ahead to see out of his vehicle, but in Spider it was different.
The LM’s docking hatch was on the top of the spacecraft, meaning he had to awkwardly crane his neck and look directly up in order to see what he was doing. Adding to the difficulty was the fact that the sun was glinting off Gumdrop’s metal body almost directly into his eyes. Scott had to help guide him in.
Eight hours after they had separated, Spider and Gumdrop re-docked. It successfully concluded the most significant portion of Apollo 9’s flight plan, and the crew rounded out the rest of the mission by conducting several scientific experiments.
Apollo 9 was such a success that NASA felt able to completely skip the next mission it had originally planned to conduct (a test of the LM in high Earth orbit). McDivitt, Scott and Schweickart had tested the LM so thoroughly that NASA was confident enough to send it all the way to the Moon with Apollo 10, the very next flight.
At the time of writing in March 2021, Apollo 9 is one of just two Apollo missions that has all three crewmembers still alive (the other being Apollo 8).