ASTP art S75-27289-origThe very last Apollo crewmembers were awoken for their trip home by a future member of the very first Space Shuttle mission.

Commander Tom Stafford, Vance Brand and Deke Slayton heard the song “Up Against the Wall, Redneck Mother” in their headsets to wake them up on their final day on orbit, piped up to them by CAPCOM Bob Crippen.

“Good morning, gents. Party’s over. Time to come home,” Crippen said.

The Apollo-Soyuz Test Project (ASTP) surely filled many at NASA and around America with emotions from all over the map. ASTP was the finish line to the great Space Race. While the United States clearly won the political race to land men on the moon, NASA officials and crews themselves always had an appreciation of their opponent, the Soviet Union. A few of the astronauts had met their counterparts over the years of the adventure to the moon and struck a few friendships despite the politics involved in “beating” the Soviets.

In fact, NASA had tried to encourage all sorts of ideas to team up in space in some capacity from the earliest days of the Space Race. In fact, cooperation with other nations in spaceflight was part of its mandate. While government officials tried to discourage any “naivete” on behalf of NASA officials and astronauts that space cooperation could lead to better political relations, NASA struck ahead to get other nations, especially the Soviet Union, to consider projects with NASA. But while American scientists were open, the Soviet scientists lacked the relative freedom to even hint that such a scientific relationship would prosper, given how the USA had also began to diversify their intercontinental ballistic missile programs.

The ICBM programs were a darker side of the Space Race where the  US never fell behind. American had several missiles that could launch and strike any Soviet target from American soil. Despite their scientific firsts in getting unmanned and manned payloads into earth orbit, Soviet rockets were somewhat weaker. The best rockets of the USSR could only travel over the Arctic Circle. This was why the Cuban Missile Crisis was such a terrifying matter. Having Soviet mobile launchers on Cuban soil would make it comparably easier to strike most US targets.

As the Soviets fell behind and the US moved forward, NASA kept courting the Soviets in some kind, any kind of cooperative venture. Soviet officials were often invited to watch space launches, but politely declined. The logic was that, if the Soviets attended a launch, they in turn would be obligated to invite US officials to one of their launches. Since the Soviet Union was a Communist state, the separation of scientist and Soviet comrade didn’t exist, making negotiations ever difficult.

But something changed by 1969. Thomas Paine took the reins of NASA as the new administrator. He encouraged a message of friendly competition while also fostering cooperation with the Soviets. Paine made very great strides in talks, particularly with the President of the Soviet Academy of Sciences, Mstislav Vsevolodovich Keldysh. Paine also got George Low, a ranking NASA action-man on the Apollo program and now his Deputy Administrator, in on the talks.

But it was Dr. Philip Handler of the U.S. National Academy of Sciences that may have turned the tide. After getting some blessings and cautions from outgoing NASA Administrator James Webb and Tom Paine, Handler had also been having talks in parallel with NASA officials.

Handler went at the Soviets in May 1970 in a more frank manner, calling them out on their reticience. But then he pulled out his trump card. He discussed the plot line of an American space-disaster film called Marooned, where an Apollo-style crew is unable to re-enter and is threatened with suffocation.

What distinctly shocked the Soviets about Handler’s discussion of the film was that it portrayed a Soviet cosmonaut as a hero, making a rendezvous with the stricken crew to give oxygen, buying time for the crew before an American rescue ship was able to arrive.

That broke the ice. By 1971, the Soviets and the Americans began to hammer out a plan.

So July 15, 1975 saw the launch of the last Apollo Command/Service Module atop a Saturn I-B, with a Soviet Soyuz launching that same day. Three hours later, the two crews had docked using a special test adapter (which also compensated for the pressure variations between the two spacecraft) and shook hands. After about a couple of days together, the crews departed and prepared to return home.

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Deke Slayton (left), the oldest rookie, with veteran Tom Stafford and fellow rookie Vance Brand. (NASA)

It was a particularly great series of days for Vance Brand, a rookie astronaut that likely lost a chance to be on an Apollo lunar mission due to project budget cuts, but also for Deke Slayton. One of the original Mercury Seven, Deke was grounded due to an erratic heartbeat.

While becoming an influential decision-maker for all Gemini and Apollo crew flight rotations, Deke never received headlines of his own until 1972, where NASA officials found the heart problem had disappeared and restored him to flight status.

Deke celebrated by enjoying some aerobatics for an hour in a T-38 trainer. NASA also felt that Deke had his due coming and assigned him to the ASTP crew.

Re-entry of the the last Apollo Command Module was uneventful until about 9 miles up. By that time, the crew should’ve armed the Earth Landing System (ELS), automation which, among other things, jettisoned the forward heat shield, also called the apex cover, so that drogue parachutes, which would eventually pull the three main parachutes for a safe landing.

The entry was a bit turbulent. Complicating matters was some squealing noise over their headsets, distracting all of them. In all of that, Vance Brand didn’t hear the callouts to activate the ELS, or Stafford wasn’t clear in calling out the activation. The Command Module fell past the normal activation altitude until Brand realized that they were falling too far. He hit the manual switches that jettisoned the apex cover and activated the drogues.

The deployment of the apex cover was a subset of the ELS, which normally turns off the reaction control jets used in re-entry. But the ELS wasn’t switched on. As the drogues opened, the spacecraft jerked a bit, and the RCS jets puffed a bit to try to stabilize the ship.

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Good parachutes belied a serious problem inside. (NASA)

Things went from weird to serious at that moment. The process to deploy the parachute system also opened vents around the spacecraft to the outside air. The crew finally switched the ELS on after thirty seconds, but some RCS exhaust entered the Command Module through the air vent.

This was bad.

The crew sniffed and could even see the yellowish gas within the cabin. But there was still work to do to prepare the spacecraft for entry and so they moved quickly to get that work done.

All thrusters and motors of the Apollo spacecraft used nitrogen tetroxide as the oxidizer and a type of hydrazine fuel. They burn on contact, making building and using engines for the Command/Service Module (and Lunar Module) spacecraft compact and highly reliable. But hypergolic fuels are extremely deadly. Just a few hundred parts per million could kill you.

Splashdown was particularly hard, perhaps 10Gs of force. The CM tipped and went into “stable two”—floating upside down, nose in the water.

By now, Brand, being closest to the steam vent (also venting the outside air) had passed out. Stafford cut any other fuel flow and deployed the floatation bags to right the spacecraft to “stable one” (right side up). Avoiding falling into the docking tunnel while grabbing the oxygen masks from the lower deck, Stafford handed one to Slayton, donned his own and put the third mask on Brand, who soon recovered in a fitful start.

The spacecraft righted and soon recovery forces moved in. Slayton, in the confusion, responded to signs from the frogmen with a “thumbs-up” sign when, he realized later, should’ve been a sign that they were in distress–and that the cabin was contaminated, which could also injure the recovery team. Worse, the recovery team didn’t rush to get the crew out as they didn’t know of the emergency. In the masks, the crew had a hard time speaking on the comm link.

The crew were moved from the spacecraft, hauled aboard their recovery carrier and soon started a press conference by phone with President Gerald Ford. All of them were still coughing and wheezing but didn’t really point out to others of their exposure to hypergolic fuel until they mentioned how good the flight was–except for that last bit before splashdown.

Then the flight surgeon put two and two together, stopped the press conference and got the crew into immediate medical treatment. It turned out that all of them were suffering a type of pneumonia from the gases, filling their lungs with fluid in reaction to the toxicity.

The crew were hospitalized for three weeks in Hawaii. Analysis later showed the crew had a 300 parts per million exposure to the gas. Where it not for Stafford’s quick thinking after splashdown, the crew may have died if further exposed to around 400 parts per million.

ASTP didn’t immediately help the general state of the Cold War, nor did it lead to additional cooperation in space right away.  It took a few years, which included the American return to space in the Space Shuttle, and the collapse of the Soviet Union to bring the more relaxed Russian Federation to a much more active relationship with the American space program, with Shuttle visits and crew rotations on their Mir space station, and later the international construction of the International Space Station.

The Partnership: A History of the Apollo-Soyuz Test Project
At Home in Space: The Late Seventies into the Eighties, by Ben Evans (book excerpt)