Forty one years ago on Feb 7, 1984, NASA astronaut Bruce McCandless II (Jun 8, 1937 – Dec 21, 2017) made the first ever untethered free flight using the Manned Maneuvering Unit (MMU) and starred in one of the most memorable images of our time.
From www.smithsonianmag.com/…
NASA PMs were terrified of the MMU. They worried that a pressure-suited astronaut in the vacuum of space was “one system away from certain death.”
McCandless and Stewart strongly argued against using a tethered MMU, saying that the MMU was intended to crawl at a few inches per second and the spacewalk would stay close to the shuttle. All systems on the MMU were redundant. In case of a total failure, the shuttle could be maneuvered to scoop up the astronaut.
Still, even some insiders couldn’t help feeling nervous about what McCandless and Stewart were about to do. NASA’s Paul Bailey, an orbital mechanics specialist who helped train astronauts to fly the jetpack, felt confident in both Martin and in Ed Whitsett, but as the STS-41B launch approached, he had a recurring nightmare: He would be sitting on the shuttle’s tail section, with Earth filling the sky, just as McCandless and Stewart floated out of the airlock. “I was looking down the cargo bay over at the MMUs. And I thought, Holy mackerel, these people think I know what I’m talking about! And they’re going to die!” Waking up in a cold sweat, Bailey would grab his MMU reference book, go through it one more time, and reassure himself he hadn’t forgotten anything.
From www.theguardian.com/…
The day before my walk, we reduced the pressure and increased the oxygen in the shuttle to get the nitrogen out of my bloodstream, otherwise I’d get the bends. Where I live now, outside Denver at an altitude of 8,300ft, has lower oxygen levels than the cabin did that day.
On the day itself, I put on my underwear, complete with airducts and flexible tubing filled with water to cool me down, and my pressure suit. The crew said, “You’re ready. Go, go, go!” so I stepped into the airlock, closed the hatch, depressurised it, opened it – and away I went.
I don’t like those overused lines “slipped the surly bonds of Earth”, but when I was free from the shuttle, they felt accurate. It was a wonderful feeling, a mix of personal elation and professional pride: it had taken many years to get to that point. Several people were sceptical it would work, and with 300 hours of flying practice, I was over-trained. My wife was at mission control, and there was quite a bit of apprehension. I wanted to say something similar to Neil [Armstrong] when he landed on the moon, so I said, “It may have been a small step for Neil, but it’s a heck of a big leap for me.” That loosened the tension a bit.
Now let’s solve today’s puzzle composed in 1894 by British Chess composer Percy Francis Blake (1873 -1936).