Neil Armstrong: Landing on the Earth, Landing on the Moon

At the time of writing, only five Americans – Jim McDivitt, Frank Borman, Neil Armstrong, Gerry Carr and Joe Engle – have commanded a crew on their very first orbital space mission. Armstrong is here pictured shortly before embarking on Gemini VIII – an already complex rendezvous, docking and EVA extravaganza, which quickly turned into something frighteningly more dramatic, which showcased his piloting skills under extreme duress. Photo Credit: NASA

History remembers Neil Armstrong as the first emissary of humanity to set foot on a world other than his own. As an astronaut, he participated in two adrenaline-charged missions, both of which left a terrestrial audience tensely perched on the edge of their seats. Launched on 16 March 1966 with crewmate Dave Scott aboard Gemini VIII, Armstrong was tasked with commanding a three-day flight to rendezvous and dock with an unmanned Agena target vehicle. The docking itself was uneventful, but within minutes the two craft entered a slight, almost imperceptible roll. Neither astronaut could have known at this stage that Gemini VIII’s No. 8 attitude thruster had short-circuited and stuck into its ‘on’ position. To correct the error, Scott cut power to the Agena’s own thrusters and Armstrong’s activated the Gemini’s thrusters in an effort to stop the roll and regain control.

For a few minutes, his efforts succeeded.

Then things went badly wrong…so wrong, in fact, that they could have reshaped the future course of history and made Neil Armstrong one of the first men to lose his life in space, rather than the first on the Moon.

As Armstrong worked to reorient the Agena-Gemini combination into its correct position, the unwanted motions resumed…albeit much faster than before and along all three axes. Perplexed, the men jiggled the Agena’s controls, then those of the Gemini, in a fruitless attempt to isolate the problem. Glancing at his instrument panel, Scott noticed that their craft’s attitude propellant had dropped to just 30 percent. At this stage, it dawned on the astronauts that the fault was with their craft. This posed its own problems, since both craft were rapidly rotating and could hit each other.

Gemini VIII noses gently into the Agena target vehicle’s docking collar, to begin the first in-space docking involving a piloted craft. Minutes after this photograph was taken, things took a distinctly ugly turn. Photo Credit: NASA

Armstrong and Scott were out of radio communications with the ground. They undocked from the Agena and fired a long burst of the Gemini’s thrusters to pull away…whereupon their craft, now free, began to spin much more violently, in roll, pitch and yaw. Since the stuck-on No. 8 thruster was no longer turning the entire combination, the oscillations were correspondingly worse than before. At length, high above south-east Asia, they came into contact with the tracking vessel Coastal Sentry Quebec. Controllers were stunned when Dave Scott’s urgent call came through.

“We have serious problems here,” he reported. “We’re tumbling, end over end. We’re disengaged from the Agena.”

Jim Fucci, the communicator aboard the ship, asked them about the problem. Quickly, and characteristically calm, Armstrong reported that they were continuously increasing in a left roll and unable to turn anything off. Fucci alerted Houston that Gemini VIII was suffering from “pretty violent oscillations”. The resultant three-way conversation with the Mission Operations Control Room meant that several seconds elapsed before Flight Director John Hodge picked up all the details; Fucci had to repeat that Armstrong was “in a roll and he can’t stop it”.

In orbit, Armstrong threw circuit breakers to cut electrical power and hence the flow of propellant to the attitude thrusters, including troublesome No. 8. However, with no friction or counter-firing thrusters to halt it, the spinning continued…reaching a horrifying sixty revolutions per minute. Checklists, flight plans and procedural charts were flung around Gemini VIII’s cabin by the resultant centrifugal force and the unfilted sunlight blazed through the astronauts’ windows with startling regularity. To Dave Scott, it was like a constant strobe light, hitting them square in the face. As they struggled to read their instruments, the two astronauts came close to physically blacking out.

Gemini VIII’s hatches are opened by rescue swimmers after Armstrong (in right-side couch) and Scott performed the Gemini programme’s first splashdown in the Pacific Ocean. Photo Credit: NASA

Aware that the problem was with his craft, Armstrong had little choice but to use Gemini VIII’s 16 re-entry thrusters to steady them. This was easier said than done…for the re-entry controls were in a particularly awkward position, directly above his head, and, worse, they were on a panel with around a dozen toggles. “With our vision beginning to blur,” wrote Scott, “locating the right switch was not simple.” Months of training had allowed the astronauts to know each switch, intuitively, but Scott was amazed at Armstrong’s skill as he reached for the toggle and grappled the spacecraft’s hand controller, at the same time. Eventually, the effort succeeded, albeit at the expense of 75 percent of Gemini VIII’s propellant. Mission rules decreed that, once the re-entry controls had been activated, the flight was aborted. Ten hours into the mission, Armstrong and Scott were on their way home.

Television stations began interrupting their programmes – Batman and, ironically, Lost in Space – to provide live coverage. Original plans had called for Gemini VIII to splash down in the Atlantic and be recovered by the aircraft carrier USS Boxer, but the emergency guided them instead to a point in the western Pacific, 500 miles east of Okinawa. A naval destroyer, the Leonard F. Mason, based off the coast of Vietnam, was assigned to this splashdown zone and her crew began steaming towards the predicted point.

The bitterly disappointed astronauts ran through their pre-retrofire checklist and tests of Gemini VIII’s thrusters finally identified the fault with No. 8. Scott later described the thruster as not exhibiting “a consistent, linear problem…it was really screwed up”. In effect, the thrusters had been ‘on’ when it should have been ‘off’ and vice versa. At 9:45 pm, Gemini VIII’s retrorockets fired above south-central Africa, in orbital darkness, which gave the astronauts no visual cues for alignment. The spacecraft re-entered over the high peaks of the Himalayas and, as it descended, Scott could see nothing through his window, save a pinkish-orange glow of superheated plasma outside…then, after a while, came high-level haze and, later, the glint of water. Ten hours and 41 minutes after launch, Gemini VIII hit the choppy waters with a harsh thump. Seasickness was an inevitability as the spacecraft’s windows rhythmically rolled and pitched, but the men stepped smartly through the shutdown of electrical and other systems. They had forgotten to take their anti-seasickness pills. “When Mission Control told us about three-foot waves,” Scott recalled, “they forgot to mention the 20-foot swells!”

Neil Armstrong’s dramatic landing on Earth in March 1966 is quite naturally eclipsed by his landing on the Moon, three years later, but the chances of survival and the immense risk were both real and profound in both cases. Late on the afternoon of 20 July 1969, he initiated Powered Descent – the main burn of the descent engine of the lunar module Eagle – high above the lunar surface. Four minutes into the descent, the lander rotated ‘face up’ so that the radar on its underside was able to acquire the lunar surface and supply altitude and rate-of-descent data. “We needed to get the landing radar into the equation pretty soon,” Armstrong told his biographer James Hansen, “because Earth didn’t know how close we were and we didn’t want to get too close to the lunar surface before we got that radar.”

Photographed by Mike Collins aboard the command module Columbia, this view shows the lunar module Eagle – carrying astronauts Neil Armstrong and Buzz Aldrin – in its first seconds of free flight on the afternoon of 20 July 1969. Shortly after this picture was taken, Armstrong initiated Powered Descent to the surface. Photo Credit: NASA

At this point a yellow caution light lit on the instrument panel and an alarm tone sounded. “Program alarm,” called Armstrong, then glanced down to the computer display and added, “it’s a 1202. Give us a reading on the 1202 program alarm.” Neither he nor Aldrin had any idea which of the dozens of different alarms the 1202 represented and certainly had no time to flip through their data books to find out. Fortunately, seated in Mission Control was Steve Bales, the 26-year-old guidance officer (nicknamed ‘Guidance’) and an expert on the lunar module’s computer. He assured Flight Director Gene Kranz that 1202 was an ‘executive overflow’, meaning the computer was momentarily overloaded, but it would not jeopardise the landing. With typical enthusiasm, Bales yelled into his mouthpiece: “We’re Go on that, Flight!”

Bales’ call was relayed to Armstrong by capcom Charlie Duke – “We’re Go on that alarm” – but it was not to be the end of the 1202: it flashed onto Eagle’s display thrice more, but so long as it was only intermittent it did not pose a risk because the computer was able to recover.

Three minutes before the scheduled touchdown on the Moon, the computer flashed a 1201 alarm. This was another form of executive overflow and was quickly cleared, with Duke telling Armstrong and Aldrin, rapid-fire, “We’re Go…Same type, we’re Go”. For Armstrong, the alarms were little more than an irritation and, as long as everything continued to look fine – and it did; Eagle was exhibiting no erratic motions – he had every intention of pressing on.

Capcom Charlie Duke (foreground) and Apollo 11 backup landing crew members Jim Lovell and Fred Haise are pictured at their consoles in Mission Control during humanity’s historic first landing on the Moon. Photo Credit: NASA

By the time the 1201 alarm appeared, the lander had already performed its ‘pitch-over’ manoeuvre and was flying tilted backward about 20 degrees off-vertical, such that the astronauts could ‘see’ the lunar terrain spread out before them. After polling his team, Kranz received a collective “Go for Landing”, a message which Duke now passed on to Armstrong and Aldrin. Yet the furore over the program alarms meant that it was another minute or so, not until a few seconds after 4:15 pm EDT, that Armstrong had chance to look at the surface…and behold a particularly unwelcoming sight: the near slope of a vast crater, as big as a football field, its environs dotted with boulders the size of small cars. At first, he considered landing ‘short’ of the crater – later dubbed ‘West Crater’ – then picking a spot somewhere amidst the boulders, although the risk of touching down on a slope or in a tight place quickly changed his mind.

At an altitude of 450 feet, a little higher than he had intended, Armstrong selected the semi-automatic mode that would enable him to control attitude and horizontal velocity, while the computer – allowing for his commands – operated the throttle. He pitched Eagle almost upright in order to direct almost all of its thrust downwards and slow the rate of descent, then selected ‘attitude hold’ and let Eagle fly a shallow trajectory over the obstacles. As soon as he was clear, he began the seek a suitable location to land.

Trajectory planners had designed the descent path to yield the longest possible shadows to improve the astronauts’ ability to discern peaks, valleys, craters and rilles. This required coming in low, shortly after dawn with the Sun behind the lander. If they had tried to land with the Sun high in the sky, the surface would have appeared flat and essentially featureless. Nevertheless, there were residual concerns that the glare of reflected sunlight might impair the astronauts’ depth perception.

As they drew closer, Armstrong began to see lunar dust, kicked up by the descent engine, beginning to obscure the surface. The dust, he told Hansen, was not just a ‘normal’ cloud like those encountered in the high desert on Earth, but effectively a ‘blanket’ – a sheet of moving dust which essentially wiped out visibility, apart from several boulders poking through it. Moving almost horizontally, the dust “did not billow up at all; it just moved out and away in an almost radial sheet”.

Further than humans had ever ventured, this electrifying view from Apollo 11 reveals the marble-sized Earth in all its splendour. Photo Credit: NASA

In Mission Control, Gene Kranz’s team knew that Armstrong had intervened early, but they did not yet know why; they could not know about the yawning crater and the forbidding field of boulders. “The partnership,” between Mission Control and the astronauts, wrote Andrew Chaikin, “had all but dissolved.” In this final phase, everyone on Earth had to understand that Armstrong, the man in command and the man ‘on the spot’, was now running the mission.

Charlie Duke called to Kranz: “I think we’d better be quiet!”

“Rog,” agreed the flight director. “The only call-outs from now on will be fuel.”

Gradually, it seemed, the situation improved and Armstrong was able to begin arresting Eagle’s forward and sideways motion with the thrusters; he intended to land in the first clear spot that he could find. He was virtually silent throughout those final minutes, the only voice coming from Aldrin, who called out a steady stream of altitudes and velocity components to guide Armstrong – and a tense, listening world – down.

“Once I got below 50 feet,” Armstrong told James Hansen, “even though we were running out of fuel, I thought we’d be all right. I felt the lander could stand the impact…I didn’t want to drop from that height, but once I got below 50 feet I felt pretty confident we would be all right.”

Ninety feet above the surface, Aldrin reported “Quantity Light”, indicating that there was only 5 percent of fuel was left in Eagle’s descent engine, and, in Mission Control, a 94-second countdown started; when this countdown reached zero, the lander would have only 20 seconds left in which to either touchdown or abort. Unfortunately, by that time, Armstrong would be too far into the Dead Man’s Curve to safely call an abort. “I never dreamed,” Kranz recounted years later, “that we would still be flying this close to empty.”

Ashore on a silent, waterless sea, this is amongst the earliest views of Tranquillity Base: our species’ first toehold on another world. Photo Credit: NASA

Watching the fuel gauge on his display like a hawk, Carlton reported that only 60 of the 94 seconds remained – an urgent report passed on to Eagle by Charlie Duke – although the astronauts were too preoccupied to respond. “They were too busy,” Kranz said later. “I got the feeling they were going for broke. I had this feeling ever since they took over manual control.” In Mission Control, the silence was so pervasive and so enduring that one could have heard a pin drop. Kranz crossed himself and prayed.

At 4:17:26 pm, Aldrin called out that they were 20 feet above the surface and, 13 seconds later, announced “Contact Light” as one of the sensor prongs projecting below Eagle’s footpads touched surface. Armstrong would later tell James Hansen that he did not react instantaneously when the light glowed blue, thinking it to have been an anomaly and not entirely certain, thanks to the dust, that they had really touched down. As a result, he was slightly a second or two late in shutting down the engine. Although there was little risk of an explosion,  the potential of damaging the engine on an inconveniently located rock made it essential to shut it down as quickly as possible. Forty seconds had now passed since Charlie Duke’s last call, yet post-mission analysis would reveal that – due to propellant sloshing around in the descent stage tanks and giving inaccurate readings – Eagle actually had around 45 seconds of fuel remaining…

Neil Armstrong, the aviator who had flown combat missions over Korea and who had guided the X-15 into the high atmosphere, had skilfully commanded and executed two of the most dramatic missions in human spaceflight history. In fact, it would not be waxing lyrical to excess to declare that he had twice saved President John Kennedy’s goal of bootprints on the Moon before the end of the decade. Had he and Scott not reacted as they did on Gemini VIII, it is certain that Project Apollo would have met with significant delay, as their prompt and timely inputs enabled a rapid technical understanding of the problems and their resolution, as well as validating rendezvous and docking in orbit. And on 20 July 1969, watched by an estimated worldwide audience of 600 million, Armstrong achieved Kennedy’s goal: a goal beyond human reach for thousands of years, a goal which even crewmate Mike Collins felt only had a 50-50 chance of success.

“Tranquillity Base here.” Those profoundly powerful words required a fraction of a second to utter, and only a few seconds to cross the vast, 240,000-mile cislunar gulf to the ears of Mission Control and the people of Planet Earth…but would be forever enshrined in our cultural consciousness. So too would the name of the man who spoke them: Neil Armstrong, the First Man on the Moon.


Tomorrow’s article will focus upon the death of Armstrong’s infant daughter, Karen, and its subsequent impact upon his aviation and astronaut career.

Missions » Apollo »

2 comments to Neil Armstrong: Landing on the Earth, Landing on the Moon