India Shows off the Spacesuit its Astronauts Will be Using in 2022

The Indian Space Research Organization (ISRO) has made immense progress since the turn of the century. From its humble beginnings, launching satellites into orbit between 1975 and 2000, the ISRO sent their first mission to the Moon in October of 2008 (the Chandrayaan-1 orbiter), followed by their first mission to Mars – the Mars Orbiter Mission (MOM) – in November of 2013.

And in the coming years, the ISRO intends to become the fourth space agency to send astronauts into space. In so doing, they will join an exclusive club of space agencies that consists of only Russia, the United States and China. Last week (on September 7th, 2018) the organization unveiled the spacesuit that their astronauts will be wearing when they make this historic journey.

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Where Can I Take Off My Space Helmet?

It’s been a while since I read the NASA manual on space helmet operation, but if I recall correctly, they really just have one major rule. When you go to space, keep your space helmet on.

I don’t care what haunting music those beguiling space sirens are playing. It doesn’t matter if you’ve got a serious case of space madness, and you’re hallucinating that you’re back on your Iowa farm, surrounded by your loved ones. Even if you just turned on an ancient terraforming machine and you’re stumbling around the surface of Mars like an idiot. You keep your helmet on.

Keep. Your. Helmet. On. Credit: NASA
Keep. Your. Helmet. On. Credit: NASA

Not convinced? Well then, allow me to explain what happens if you decide to break that rule. Without a helmet, and your own personal Earth-like atmosphere surrounding you, you’ll be exposed to the hard vacuum of space.

Within a moment, all the air will rush out of your lungs, and then you’ll fall unconscious in about 45 seconds. Starved for oxygen, you’ll die of suffocation in just a couple of minutes. Then you’ll freeze solid and float about forever. Just another meat asteroid in the Solar System.

That’s the official stance on space helmet operation, but just between you and me, there might be a little wiggle room. A few other places in the Solar System where you can take your helmet off for just a moment, and maybe not die instantaneously.

Earth is obviously safe. If you’re down here on the planet, and you’re still wearing your helmet, you’re missing the whole point of why you need a helmet in the first place. That space helmet rule only applies to space, silly, you can take it off down here.

In order to survive, the human body needs a few things. First, we need pressure surrounding our body, and helping to keep our lungs inflated. The Earth’s atmosphere provides that service, stacking a huge column of air down on top of you.

Without enough pressure, the air will blast out of your lungs and you’ll suffocate. Too much pressure and your lungs will crush and your heart will give out.

You’re going to want atmospheric pressure somewhere between .5 to 5 times the atmosphere of Earth.

If you can’t find air, then some other gas or even water will do in a pinch. You can’t breathe it, but it can provide the pressure you’re looking for.

Do not take your helmet off on the Moon. Credit: NASA

If you’ve got the pressure right, then your next priority will be the temperature. You know what it’s like to be too cold on Earth, and too hot, so use your judgement here. It’s too cold if you’re starting to die of hypothermia, and too hot if you’re above 60 C for a few minutes.

If you really want to thrive, find air you can breathe. Ideally a nice mixture of nitrogen and oxygen. Again, here on Earth, that column of air pushing down on you also allows you to breathe. If you swapped air for carbon dioxide or water, you’re going to need to hold your breath.

So what are some other places in the Solar System that you could take your helmet off for a few brief moments?

Your best bet is the planet Venus. Not down at the surface, where the temperature is hot enough to melt lead, and it’s 90 atmospheres pressure.

But up in the cloud tops, it’s a whole different story. At 52.5 kilometers altitude, the temperature is about 37 C. A little stifling, but not too bad. And the air pressure is about 65% Earth’s air pressure.

Credit: NASA
Hold your breath if you’re planning on taking off your helmet within the clouds of Venus. Credit: NASA

The problem is that this region is right in the middle of Venus’ sulphuric acid cloud layer, so you might inhale a mist of toxic acid if you tried to breathe. Not to mention the fact that Venus’ atmosphere is carbon dioxide, which means you’ll asphyxiate if you tried to breathe it.

But assuming you had some kind of air supply to breathe, and a suit to protect you from the sulphuric acid, you could hang around, without a helmet as long as you liked.

Take that! Overly draconian NASA helmet rules.

Out on the surface of Titan? Good news! The surface pressure on Titan is 1.45 times that of Earth. You won’t need a pressure helmet at all, ever. You will need a warming helmet, however, since the temperature on Titan is -179 C. You might be able to take that helmet off for a brief moment, before your face freezes, but don’t take a breath, otherwise you’ll freeze your lungs.

Want another location? No problem. Astronomers are pretty sure there are vast reservoirs of water under the surface of many moons and large objects in the Solar System, from Europa to Charon.

This artist's concept of Jupiter's moon Ganymede, the largest moon in the solar system, illustrates the club sandwich model of its interior oceans. Credit: NASA/JPL
This artist’s concept of Jupiter’s moon Ganymede, the largest moon in the solar system, illustrates the club sandwich model of its interior oceans. You could try taking your helmet off while diving in them. Credit: NASA/JPL

They’re heated up through tidal interactions, and could be dozens of kilometers thick. Drill down through the ice sheet, and then just dive into the icy waters without a helmet. It’ll be really cold, and you won’t be able to breathe, but you can stay alive as long as you can hold your breath.

Did you jump out of your spacecraft and now you’re falling to your death into one of the Solar System’s gas giants? That’s bad news and it won’t end well. However, there’s a tiny silver lining. As you fall through the atmosphere of Jupiter, for example, there’ll be a moment when the temperature and pressure roughly match what your body can handle.

Go ahead and take your helmet off and enjoy that sweet spot before you plunge into the swirling hydrogen gas. Once again, though, don’t breathe. Hold your breath, the moment will last longer before you go unconscious.

And listen, if you really really need to take off your helmet in the cold vacuum of space, you can do it. Make sure you completely exhale so you don’t wreck your lungs. Then you’ve got about 45 seconds before you go unconscious.

That’s enough time to jump across to an open airlock, or kick that nasty xenomorph holding onto your leg into deep space.

Even though the NASA space helmet manual has one rule – keep your helmet on – you can see there are a few times and places where you can bend those rules without instantly dying. Use your judgement.

I’d like to thank Mechadense for posting a comment on an earlier Guide to Space YouTube video, which became the inspiration for this episode. Thanks for doing the math Mechadense and bringing the science.

Gallery: Spacesuits Are Amazing Human-Protection Machines

Did you know it’s been nearly 50 years since the first spacewalk? On March 18, 1965, Russian Alexei Leonov ventured from the safety of his Russian spacecraft for the first attempt for a person to survive “outside” in a spacesuit. While Leonov had troubles returning to the spacecraft, his brave effort set off a new era of spaceflight. It showed us it was possible for people to work in small spacesuits in space.

Think about what spacewalks have helped us accomplish since then. We’ve walked on the Moon. Constructed the International Space Station. Retrieved satellites. Even flew away from the space shuttle in a jetpack, for a couple of flights in the 1980s.

In this gallery, we’ve highlighted some of the more memorable images from American spacewalks over the years to honor a new Smithsonian Air and Space exhibit opening today (Jan. 8).

Chris Cassidy with Earth as a backdrop during the EVA on May 11, 2013. Credit: NASA.
Chris Cassidy with Earth as a backdrop during the EVA on May 11, 2013. Credit: NASA.
Ed White did the first American spacewalk in 1965. Obviously, he wore a spacesuit. Credit: NASA
Ed White did the first American spacewalk in 1965. Obviously, he wore a spacesuit. Credit: NASA
"Knocking on the door to come back in from space after yesterday's spacewalk," said Ron Garan via Twitter. Credit: NASA
“Knocking on the door to come back in from space after yesterday’s spacewalk,” said Ron Garan via Twitter. Credit: NASA
Astronaut Eugene Cernan from Apollo 17, the last mission to the Moon (NASA)
Astronaut Eugene Cernan from Apollo 17, the last mission to the Moon (NASA)
Astronaut Drew Feustel reenters the space station after completing an 8-hour, 7-minute spacewalk at on  Sunday, May 22, 2011. He and fellow spacewalker Mike Fincke conducted the second of the four EVAs during the STS-134 mission. Credit: NASA
Astronaut Drew Feustel reenters the space station after completing an 8-hour, 7-minute spacewalk at on Sunday, May 22, 2011. He and fellow spacewalker Mike Fincke conducted the second of the four EVAs during the STS-134 mission. Credit: NASA
NASA astronaut Garrett Reisman takes a self-portrait visor while participating in the first of three spacewalks. Credit: NASA
NASA astronaut Garrett Reisman takes a self-portrait visor while participating in the first of three spacewalks. Credit: NASA
Manned Maneuvering Unit
NASA Astronaut Bruce McCandless flying in the Manned Maneuvering Unit in 1984. Image Credit: NASA
Astronaut Richard Arnold during the mission's first spacewalk.  Credit: NASA
Astronaut Richard Arnold during the mission’s first spacewalk. Credit: NASA
Dust flies from the tires of a moon buggy, driven by Apollo 17 astronaut Gene Cernan. These "rooster-tails" of dust caused problems. Credit: NASA
Dust flies from the tires of a moon buggy, driven by Apollo 17 astronaut Gene Cernan. These “rooster-tails” of dust caused problems. Credit: NASA

Gallery: Diving For Spacewalks Is Way Tougher Than You Think

If you’ve spent any length of time underwater, you appreciate just how much drag it creates on your limbs — especially if you’re wearing a little clothing or carrying around diving equipment. Now, try to imagine using a pressurized spacesuit in that environment. You’re already puffed up like a balloon and have the drag to contend with.

Few of us will get that experience — NASA won’t let just anybody try on an expensive suit — but luckily for us, a person saying he is a diver (identifying himself only as Zugzwang5) posted about the experience on Reddit. The pictures alone are incredible, but the insights the diver provides show just how tough an astronaut has to be to get ready for spacewalking.

Using the spacesuit compared to a wetsuit, wrote Zugzwang 5 on Reddit, was “incredibly cumbersome”. He says he’s a contracted diver for Oceaneering working at NASA’s Neutral Buoyancy Laboratory in Houston, which has a model of the International Space Station in a huge pool for astronauts to practice spacewalking. Usually he’s inside a wetsuit, but the spacesuit was a completely different experience, he said.

There’s so much resistance from the suit and the water every motion takes tremendous effort. You might not guess it from my pictures, but I’m actually pretty fit, and I was exhausted by the end of the day. The hardest thing to get used to was moving up and down in the water column. I’ve been diving so long controlling my buoyancy is basically a force of will at this point, having to actually crawl and direct myself up and down was such a weird feeling.

A diver at NASA's Neutral Buoyancy Laboratory in Houston tries out a spacesuit during a practice dive in December 2014. Credit: Zugzwang 5/imgur
A diver at NASA’s Neutral Buoyancy Laboratory in Houston tries out a spacesuit during a practice dive in December 2014. Credit: Zugzwang 5/imgur

Near the end of the marathon session, the diver had to bring back a simulated “incapacitated” astronaut to the airlock underwater, which he wrote was an extremely difficult task — especially while so tired.

So, for a real astronaut to pass their final evaluation they have to do a flawless incapacitated crew member rescue. this is actually very difficult as safely manipulating another suit is even more tiring and cumbersome than just moving your own. not only that but the airlock is very small, and safely (using proper tether technique) hooking someone else up into it is a surprisingly complex procedure where you have zero extra space to work with. Thirty minutes usually ends up being hardly enough time for the new guys, and even a vet will take more than 20.

You can check out the entire gallery at this link. Also, look at a past one the diver posted about the spacesuit fitting.

Winning Z-2 Spacesuit Prototype Design Gets Ready For ‘Test Campaign’

Striking a Buzz Lightyear-like pose above is the winning design for NASA’s Z-2 spacesuit prototype. The version, called “technology”, was by far the popular vote in an online contest the agency held to choose between three prototypes, garnering 62% of 233,431 votes.

While this will never be used in space, NASA said the next-generation prototype will be useful in helping design future spacesuits. And this prototype will go through a “test campaign” that includes vacuum tests, pool tests in NASA’s Neutral Buoyancy Laboratory and in an area at the Johnson Space Center that simulates the surface of Mars.

“With the agency laser focused on a path to Mars, work to develop the technologies astronauts one day will use to live and work on Mars has already begun. Each iteration of the Z-series will advance new technologies that one day will be used in a suit worn by the first humans to step foot on the Red Planet,” NASA stated.

To learn more about the suit and the differences from its predecessor, the Z-1, check out this recent Universe Today article.

Spacesuit Leak: Why It Took NASA 23 Minutes To Send Astronaut To Safety

It took NASA almost the same amount of time as a sitcom episode to send Luca Parmitano back to the airlock when the Italian astronaut experienced a leak in his spacesuit last summer, a new report reveals.

The 23-minute gap of time between when Parmitano first sent a report of water in his helmet, to when NASA told him to go back to safety, exposed the astronaut “to an increased level of risk”, the report said. While Parmitano emerged from the incident safely, in his last minutes inside the spacesuit the water was covering his eyes, getting close to his nose and mouth, and affecting the communications equipment.

 

“There wasn’t an issue of anything being hidden or surprised. It was a lack of understanding about the severity of the event. It was believed a drink bag caused the leak,” said Chris Hansen, the chair of the mishap investigation board, in a press conference today (Feb. 26).

This misunderstanding, added Hansen (who is also the chief engineer of the International Space Station Program) also led to a problem when a leak occurred in the same suit just the week before.

Parmitano’s water leak occurred July 16 when he and Chris Cassidy were preparing a part of the International Space Station for a new Russian module. Until today, however, few knew about the existence of a second leak in the same spacesuit that happened on July 9, when Cassidy and Parmitano were doing another spacewalk together.

Astronaut Chris Cassidy works with Luca Parmitano's spacesuit, which had a water leak on July 16, 2013. Credit: NASA
Astronaut Chris Cassidy works with Luca Parmitano’s spacesuit, which had a water leak on July 16, 2013. Credit: NASA

After the conclusion of “EVA 22” on July 9, as NASA called the extra-vehicular activity, Parmitano took off his helmet and crew members discovered between 0.5 and 1 liters (0.13 to 0.26 gallons) of water inside. Cassidy told the ground that he could not see any water during the spacewalk or repressurization, leading NASA to conclude the water got into the helmet in the airlock.

“Also,” the report noted, “[Parmitano] was looking down and leaning forward and likely had pressed on the drink bag with his chest and could have pinched the bite valve open with his chin, releasing water into his helmet. The ground team accepted the crew’s drink bag leak assessment and the presence of excessive water in the helmet was not investigated further … The ground team instructed the crew to use a new drink bag for the upcoming EVA 23, which they did.”

Hanson emphasized that the crew did not make the final call, and that the ground team did ask some questions about what was going on, but the assumption that a drink bag caused the water was also a key feature of the July 16 spacewalk when the leak began to show itself in earnest.

ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.
ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.

Also, NASA did not well understand the physics of how water worked inside of the suit, assuming there was no way for liquid to make it past a fan pump separator into the helmet unless the fan itself shut off. If that scenario arose, NASA would have kicked into a 30-minute return-to-airlock procedure, and that was in the back of controllers’ minds as they were working through the fault tree during the July 16 spacewalk, officials said in the phone call today.

In the short term, the authors of the report have several  “Level 1” or priority recommendations that they should be implemented before normal spacewalks resume. NASA said it’s planning to work through these and “Level 2” recommendations in time for June, with the aim of getting spacewalks going again in July or August.

NASA astronaut Mike Hopkins holds a spare ammonia pump module during a spacewalk Dec. 24, 2013. Hopkins and fellow Expedition 38 Rick Mastracchio (top) performed two spacewalks to replace a pump blamed for crippling one of the International Space Station's two cooling loops Dec. 11. Credit: NASA TV (screenshot)
NASA astronaut Mike Hopkins holds a spare ammonia pump module during a spacewalk Dec. 24, 2013. Hopkins and fellow Expedition 38 Rick Mastracchio (top) performed two spacewalks to replace a pump blamed for crippling one of the International Space Station’s two cooling loops Dec. 11. Credit: NASA TV (screenshot)

Emergency spacewalks can still go forward, as the agency has new safety measures in place (including snorkels). This happened in December as the astronauts replaced a faulty ammonia pump.

The agency has no pressing spacewalk tasks at this time. The broken pump, sitting in temporary stowage outside the station, was initially safed to stay there until summer, but further analysis shows that it could sit there for several months more.

You can read the entire 222-page report here. We’ll pull out more highlights tomorrow after we have some time to look over it in more detail, too. The exact cause of the leak is still under investigation.

Spacesuit Water Leak Prompts NASA Mishap Investigation

In the wake of a spacesuit water leak that sent two astronauts back to the airlock early during a spacewalk last week, NASA has convened a board to look at “lessons learned” from the mishap.

The cause of the leak, which filled Luca Parmitano’s helmet with water, is still being investigated. Some media reports say it may have been a fault within the spacesuit’s cooling system. NASA stated it plans to “develop a set of lessons learned from the incident and suggest ways to prevent a similar problem in the future.”

Chairing the board will be Chris Hansen, the International Space Station’s chief engineer at NASA’s Johnson Space Center in Houston. The other four members, who are all from NASA, include:

  • Mike Foreman, NASA astronaut, Johnson Space Center;
  • Richard Fullerton, International Space Station safety and mission assurance lead, Office of Safety and Mission Assurance, NASA headquarters;
  • Sudhakar Rajula, human factors specialist, Johnson Space Center;
  • Joe Pellicciotti, chief engineer, NASA Engineering and Safety Center, Goddard Space Flight Center.

The July 16 spacewalk stopped early at 1 hour, 32 minutes, far shorter than the crew’s planned 6.5-hour outing. All of the tasks can be easily pushed off to another time, NASA has said. The astronauts were preparing data cables and power for a Russian laboratory module that should reach the station by early 2014, among other tasks.

ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.
ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.

During and immediately after the spacewalk, NASA said the crew was in no immediate danger. A few days afterwards, Parmitano reassured officials at the European Space Agency. “Guys, I am doing fine and thanks for all the support. I am really okay and ready to move on,” he said, as reported in an ESA blog post.

Still, there was so much water inside the helmet that after a time, Parmitano had trouble hearing and communicating with his crewmates. “Squeeze my hand if you’re fine,” fellow EVA member Chris Cassidy said to Parmitano during the spacewalk.

NASA also noted there is an engineering analysis happening that is “focused on resolving equipment trouble in an effort to enable U.S. spacewalks to resume.” The board, by contrast, will be looking at aspects such as quality assurance, flight control, operations and maintenance with an eye to improving NASA human spaceflight activities in general.

NASA did not immediately release a date by which it expects the investigation to finish. Meanwhile, at least one news outlet reported that the agency is rushing some spacesuit repair tools on to a Russian Progress supply ship that will leave Kazakhstan for the International Space Station on Saturday.

Source: NASA

Can You Solve This Apollo 1 Spacesuit Mystery?

Reader Jeff Arnoldi recently approached me with an intriguing question about this Apollo 1 picture:

Note that the U.S. flag is on their right shoulders. Every other Apollo mission crew and all mission crews since then wear the flag on their left shoulders.  Did the astronauts change after the Apollo 1 fire?  Why did they make the change?

In response, Universe Today put a call out to several people with knowledge of those spacesuits that were used in the Apollo 1 mission, which ended fatally in January 1967 when all three crew members died in a pad fire.

A lot of redesigns were made to the equipment to prevent the same situation from happening again, but it appears the flags were not that crucial to the spacesuit design — even though a new spacesuit was used in Apollo 7.

Weeks of searching later, we have some great theories from the experts about why the flags were switched, but no definitive answer. Feel free to let us know if you have heard anything!

There’s some important historical context about the suit that we’ll get into in a moment, but first, here’s some feedback we received from a few spacesuit experts:

The Apollo 1 crew training at North American's Downey Facility. Note the flags aren't on the spacesuits in this shot. Left to right: Virgil "Gus" Grissom Roger Chaffee, Edward White. Credit: NASA
The Apollo 1 crew training at North American’s Downey Facility. Note the flags aren’t on the spacesuits in this shot. Left to right: Virgil “Gus” Grissom Roger Chaffee, Edward White. Credit: NASA

Walter Cunningham, Apollo 7 astronaut and backup crew member for Apollo 1:

Our crew, obviously, wore both. We were concerned about flexibility and security of the suits. We had no time to be concerned with style or decorations. I know of no policy decision on the question you asked.

Shawn McLeod, field operations manager for David Clark Co. (which constructed the suit):

Our archives indicate photos in the field of the Apollo A1-C suits both with and without the U.S. flag. Based on our literature search, our team believes positioning/placement of the U.S. flag was more than likely performed in the field after the suits were delivered from David Clark Company. Field installation of patches is not unusual – especially, for a program as fast-paced as Apollo. […]

Anecdotal evidence leads us to believe that the flags were sewn on whichever arm there was room. The left arm has a pencil pocket, and maybe with the pencils sticking out they would cover part of the flag, whereas the right arm has the neck seal pocket and a little more room. Furthermore, the referenced photo shows the flag was incorrectly positioned per U.S. Flag code. If they wanted to use a flag on the right sleeve, they would need to use the version with the field of stars facing forward. Perhaps someone noted that at some point and the correction was made.

Ronald Woods, NASA spacesuit expert for 45+ years:

I spoke with one of the suit technicians that supported Apollo 1 and he didn’t remember the flags being on the right arm. I have seen them in several pictures of the Apollo crew at different events, all on the right arm.  Not sure at this time why and who may have sewn them on. During Apollo, we technicians would only sew the crew patches on the flight suits several weeks before launch.

Nicholas de Monchaux, author of Spacesuit: Fashioning Apollo:

I think there is a simple explanation, which is that the Apollo 1 suits were modified Gemini suits made by the David Clark Co., and the Apollo 7 suits were the first generation of [newer manufacturer] ILC suits. My guess is that two different manufacturers took two different approaches.

Apollo 1's crew in another spacesuit shot. From left to right: Virgil "Gus" Grissom, Edward White and Roger Chaffee. Credit: NASA
Apollo 1’s crew in another spacesuit shot. From left to right: Virgil “Gus” Grissom, Edward White and Roger Chaffee. Credit: NASA

To learn more about this type of Apollo spacesuit, Universe Today approached Cathy Lewis — a curator who specializes in spacesuits at the Smithsonian National Air and Space Museum.

Intriguingly, it appears every NASA spacesuit that has a flag on it — besides the A1-C used in Apollo 1 — has its flag on the left. More from Lewis:

In all other suits in our collection where a flag is present, the flag is on the left.  The collection includes suits made for NASA for programs and those made as prototypes and suits made for the USAF [United States Air Force] for the Manned Orbiting Laboratory program.  Just as a note there were no flags in the Mercury suits that B.F. Goodrich made for NASA.

As the Bill Nye: The Science Guy show used to repeat … but wait, there’s more.

Lewis also gave us some great background on the suits used for Gemini and Apollo. The Apollo missions actually had two different sets of pressure garments — the A1-C and the A7-L, while the Gemini missions used the G4-Cs. Essentially, the G4-C and A1-C suits were the same thing (a high-altitude suit design adapted for space), made by the same prime manufacturer — David Clark Co. The next set of suits, the A7-L (made exclusively for space work), had ILC Dover as the prime manufacturer.

Lewis added that she does not see the flag switch as being tied to the change in manufacturer.

Gemini 4 astronaut Jim McDivitt reviewing a crew procedures book in a trailer on the way to the launch pad. His flag was on the left shoulder. Credit: NASA
Gemini 4 astronaut Jim McDivitt reviewing a crew procedures book in a trailer on the way to the launch pad. His flag was on the left shoulder. Credit: NASA

Lewis did a great job summarizing a lot of history in a few paragraphs, so we decided to include her entire e-mail here.

It is not likely to have anything to do with the manufacturers per se, because, DCC had placed the flag on the left shoulder for the Gemini program. The shift between DCC and ILC is a very long and complex story that began in 1962 with the first solicitations for suit prototypes for the Apollo program. ILC was selected as the suit manufacturer in 1965 with Hamilton Standard as the primary contractor by virtue of their government contracting and systems engineering experience.

That corporate relationship fizzled and left NASA with the option of putting off the design of the Moon-walking suits and falling back on their Earth orbital experience with DCC and Gemini for the early, Earth-orbiting Block I missions.

While DCC was making A1-C suits based on the G4-Cs that Ed White had used for the first US spacewalk, they were also competing with ILC, HS and others for the new Moon-walking suit contract.

The 1967 Apollo 204 fire changed NASA’s plans for different Block I and Block II (lunar orbiting and lunar landing) spacesuits. The resulting contract went again to ILC as primary with HS [Hamilton Standard] as sub with responsibility for the life support systems and systems integration for a suit that worked in Earth and lunar orbit and moon-walking.

Unless I am missing something, I don’t see an engineering issue over the placement of the flag.

If you have any other thoughts about why the flag switch occurred, feel free to let us know in the comments!