By Andy Cooke
Spaceflight is hard. Manned spaceflight doubly so.
To get to low Earth Orbit, you need to leave the atmosphere (this is actually the easy part) and accelerate to 17,000 miles per hour. Mach 25. Thirty times the speed of a 747.
To do this, the only way that’s yet worked is to perch whatever-it-is you want to launch on top of a large rocket filled with extremely explosive substances and burn them in a (hopefully) controlled fashion.
A rocket that, as the Apollo astronauts wryly observed, is always composed of tens-to-hundreds of thousands of parts all provided by the lowest bidder.
Inevitably, there have been sad losses. The Apollo 1 fire, the Soyuz 1 crash, the Soyuz 11 fatalities, Challenger, Columbia, SpaceShip Two. Here, though, we’re going to look at five key points where disaster loomed, but didn’t materialise.
The point of this series is to identify potential Points of Divergence, where the disaster that didn’t happen could have caused a significant timeline change. This means that a number of Soviet incidents, all of which were kept secret, don’t make the cut. If you'd like to read more on Soyuz T-10, Soyuz 18-1, and Soyuz 23, or to talk about the 1997 Mir fire, just ask me to say more in the comments...
Here, then, are five almost-disasters where the dice roll came up positive:
5 – Voskhod 2: The first spacewalk doesn’t trap the spacewalker outside.
As the Space Race heated up, the Soviets tried to gain a step on the upcoming Gemini programme in the US. Voskhod 2 would have an inflatable airlock to allow a cosmonaut outside into space for the first time.
On 18th March 1965, Alexei Leonov made his way into the inflated airlock, depressurised it, and drifted into free space. Leonov quickly encountered problems in carrying any tasks outside, as his spacesuit ballooned out under pressure and stiffened at all the joints, making closing his hand or even moving his arms or legs very difficult.
Then, at the end of the spacewalk, Leonov found that his expanded suit made it impossible to re-enter the airlock. As his co-pilot, Pavel Belyayev, began to contemplate carrying out a re-entry with his comrade stuck outside, Leonov, in desperation, started to let air out of his suit. He reached the safety limits on pressure – and still couldn’t bend enough to get back in. In a race between losing consciousness due to lack of air and low pressure, and the mobility of his suit joints, he finally managed to get back inside.
Otherwise, near the dawn of the Space Age, the first man to spacewalk would have died outside the capsule.
4 – Apollo 12: The second moon landing doesn’t end with the astronauts hitting the ocean at terminal velocity.
Apollo 12, the second moon landing, launched on 14th November 1969, with its destination being the Ocean of Storms on the Moon. It is therefore dramatically ironic that it launched into a storm at Kennedy Space Centre, struck twice by lightning as it ascended.
All the electronics went haywire. Rookie astronaut Al Bean was the only one on board who understood the instruction from Mission Control: "Set SCE to Aux." He turned a near-forgotten switch to set the Signal Control Electronics to Auxiliary mode - and everything came back on. The relieved crew started to relax.
Mission Control were not so sanguine. They analysed the video of the lightning strike and realized at least one stroke had hit the spacecraft very close to the pyrotechnics that fired the parachutes for splashdown. There was every chance they'd been triggered early - but it would be impossible to tell until re-entry was over. If, then, the pyrotechnics had been already fired, the parachutes would not deploy an the Command Module would smash into the ocean at terminal velocity.
On the philosophy that the spacecraft might as well go to the Moon before trying re-entry and that there was no point in stressing the crew over something nothing to do anything about, they didn't pass this on to Conrad, Gordon, and Bean.
And, as it turned out, the pyros were fine.
3 – STS-27: One flight after the Shuttle’s triumphant Return To Flight, Shuttle Atlantis doesn’t disintegrate on re-entry.
The Challenger disaster in 1986 rocked NASA to the core. Never before had they lost astronauts in flight. NASA completed an exhaustive investigation and re-did their processes from top to bottom, before finally flying Space Shuttle Discovery on mission STS-26: Return To Flight. It was a triumph, and the Shuttle officially returned to service.
Nine weeks later, Space Shuttle Atlantis launched on a "black" mission, to orbit a reconnaissance satellite for the US DoD. Less than ninety seconds into the launch, a piece of insulation fell from one of the solid rocket boosters and struck the right hand wing and side of Atlantis. No-one noticed - initially.
The following day, someone on the ground reviewing the tapes of the launch noticed it. They contacted Atlantis and asked them to check it out with a camera on the robot arm. When the astronauts on board saw the damage - hundreds of tiles were gone and it looked as though the damage went right through - the crew thought they were doomed.
As it was a classified mission, the video contact with the ground was very limited, and when the poor-resolution images got back to Houston, NASA decided it would be fine. The astronauts - with far better images - weren't so sanguine.
As they prepared for re-entry, Commander Hoot Gibson worked out if they were going to burn up, the right and left elevons would start to "split" (which is indeed what later happened on Columbia) and calculated he'd then have about sixty seconds left to let Mission Control know what he thought of their analysis. Fortunately, though, Atlantis survived re-entry after all.
The subsequent investigation staggered NASA. To this day, Atlantis is still the most badly damaged spacecraft ever to make it through re-entry and landing. Losing a Shuttle immediately after the Return To Flight would have had huge repercussions.
Unfortunately for the crew of Columbia on STS-107, NASA didn't learn their lesson from this near-miss.
2 – Apollo 10: The dress-rehearsal for the first Moon landing doesn’t crash into the lunar mountains
The clock was running down to the end of the decade. It was now May 1969, and Apollo 10 to prove all components of the Apollo system ready for Apollo 11 to attempt the first landing.
Tom Stafford, John Young, and Gene Cernan entered lunar orbit on May 21st, on board Command Module Charlie Brown, and Stafford and Cernan prepared Lunar Module Snoopy to go through its paces (Note - NASA had words with the astronauts about naming spacecraft after this).
Snoopy was just a little too heavy to successfully land and take off again, but the mission didn't include a landing. It was to detach from Charlie Brown, descend to an altitude of 50,000 feet above the Moon (testing the engines, guidance system, and landing radar), before simulating an abort, detaching the ascent stage from the descent stage, and powering back up to dock with Charlie Brown.
Unfortunately, one switch wasn't flicked. The innocuously named AGS/PNGS switch.
This meant that the computer and the pilots were both flying the spacecraft, leading to doubled inputs. Quarter of a million miles from home, 50,000 feet above the Moon, Snoopy started to tumble - while on full ascent power. It spun head over heels at least eight times before the startled astronauts worked out what had gone wrong and flicked the correct switch (Cernan was later censured for swearing at the time, which I always considered a bit harsh...).
Had they tumbled a few more times, it would have been irrecoverable and Snoopy would have smashed into the lunar surface, killing Stafford and Cernan. Two months before Apollo 11 was scheduled to launch.
1 – Apollo 11: Does not run out of fuel before landing.
The one space mission known to virtually everyone.
Apollo 11 first landed humans from Earth on the Moon. Neil Armstrong and Buzz Aldrin descended in Eagle, while Mike Collins orbited overhead in Columbia.
On July 20th 1969, as Eagle descended past the 50,000 feet altitude reached by Snoopy, two months earlier, Armstrong realised that they were passing landmarks two seconds ahead of schedule - meaning that they were going to come down two miles beyond their aiming point. Then the first of what would be a series of computer alarms went off - the computer wasn't able to handle all the information coming at it.
The engineers at Mission Control swiftly determined it wasn't a risk, and they pressed on. Half way through the long burn, pitching up and rotating to give the astronauts a view, at 7,500 feet.
Armstrong did not like the view. They'd passed their aiming point, which had been flat and clear, and they were over a crater the size of a football field, descending into it. Beyond was a field of boulders. Armstrong took control from the computer and slowed the descent, aiming to go long, to a flatter area.
But Eagle only had a small amount of fuel left. At 350 feet altitude, it skittered past the boulders. Fuel at eight percent - less than in any simulation they'd successfully landed.
He saw a smooth landing spot, while he was 200 feet up - and the DESCENT QTY warning light came on. Ninety seconds of fuel left, and twenty of that needed to be held for the abort, if they needed to abort.
Mission Control were silent as they slowly descended to fifty feet, then thirty, then twenty. Now they were in the Death Zone - an abort from this height would result in them being caught in the explosion of the jettisoned descent stage below.
Thirty seconds of fuel left. Less. Then... "Contact light." The probe under Eagle had touched the surface. They settled down with about twenty seconds of fuel left.
No other lunar mission came anywhere near as close to running out of fuel on descent. But, as it turned out, they had just enough to do the mission and step out onto the Sea of Tranquillity.