Are rescue spacesuits useless?

[magnemoe]

8 hours ago, kerbiloid said:

Below the 7 km altitude? Not critical. Anyway, a breathing mask would be enough for comfort.

1. They would live even with aircraft masks, as their bodies were not damaged, they died from suffocation.
The decompression was not explosive, there was just a finger-thick opening.
If the hole was bigger, they would die like Columbia, from midair crash.

2. A tiny flap or gag with a tiny spring would close that vent hole in a second until the pressure gets normal, so even masks would not be required.
That was a stupid construction of the vent valve and lack of on-ground testing. It was replaced and never happened again.

Below 7 km, yes, probably no need for masks unless main parachute was open as they would be falling very fast. 
Soyuz 11 de-pressurized in space, above 20 km masks don't help you much as even breathing pure oxygen you don't get enough into your lungs. 
Suits however would helped. 

Suits are useful  in some settings. Damage during abort at high attitude like the Soyuz abort after dropping the tower if the abort was messed up somehow, Soyuz abort is a bit complex as you need to separate from the service module and the orbital module. 
burn damage from reentry this can include an high attitude abort who can generate leaks. Various stuff in orbit who makes leaks, from seals and valves braking to life support issues and getting down takes time more time if you don't need to do desperate stuff as you need to get down asap. 
Docking is another one, something goes wrong and you crashes and then has to reenter. 
Ans they are not very heavy, the Boeing ones looks very light weight, SpaceX helmets doubles as crash helmets. 

[Superfluous J]

I don't quite understand the argument. Are they really expensive? Uncomfortable? Restrictive to the point of being dangerous?

What does not wearing them accomplish, that is better than shaving off a slight chance of horrible death?

[kerbiloid]

  

6 hours ago, RCgothic said:

The main threat to spacecraft on orbit is micrometeoroid damage.

In 1950s.

6 hours ago, RCgothic said:

Those produce punctures, that may be behind trim or panels and not immediately accessible. That's what the pressure suits are for. Cabins can depressurise alarmingly quickly through surprisingly small holes.

Still no spaceship ever damaged by a micrometeorite.

If the meteoroid hole is big like in Columbia, they are anyway doomed.
The capsule can't reenter, and a rescue ship is just a dream. And anyway, without the pressurized hull they have just 2 hours of breathing in suits. Just 1 orbital turn, absolutely no rescue ship could help.

5 hours ago, magnemoe said:

Below 7 km, yes, probably no need for masks unless main parachute was open as they would be falling very fast. 

If the parachute was entered at near-sonic speed, it would be teared apart.

And 150 m/s = 540 km/h is just the speed of WWII fighter.

5 hours ago, magnemoe said:

Soyuz 11 de-pressurized in space, above 20 km masks don't help you much as even breathing pure oxygen you don't get enough into your lungs. 

While I can agree with this,

the

5 hours ago, magnemoe said:

Docking is another one, something goes wrong and you crashes and then has to reenter. 

looks highly doubtful.

Remember the famous Progress _& vs Mir docking.
They made a hole which was never fully repaired, put the module out of order, and was leaking until splashing.

(And it was ~6 t Progress).

Imagine same hole in the docking compartment of the spaceship.
Soyuz. The crew sits in separated capsule. If the habitat crashed, they just return to home in the intact capsule, and need no suits.
Shuttle/Buran: The crerw sits in cabin, the docking compartment is separated. If it's crashed, they just return. The cabin stays pressurized, suits are not needed.
TKS. 1 of crew sits in capsule, 2 of crew sit in cabin in suits. If they crash, they actually want suits to move into the capsule and escape. But the capsule isn't the ship cabin, so no need in docking suits inside the capsule on launch.
All American capsule ships (Gemini, Apollo, CST-100, Orion, Dragon). They dock with cabin. If they crash, the cabin cracks and unlikely can reenter. Rescue ships do not exist. So, in case of failed docking the suits just give them 1 orbit turn of agony.

4 hours ago, Superfluous J said:

I don't quite understand the argument. Are they really expensive? Uncomfortable? Restrictive to the point of being dangerous?

What does not wearing them accomplish, that is better than shaving off a slight chance of horrible death?

I'm just looking at the Space-X fancy suits and recall that the only flight where the suits could really help is exactly that one Soyuz-11 flight, where the problem was not in meteorites, crashes, bursts, or so, but just in valve construction. It was easily repaired in Soyuz-12 and never appeared again, and highly likely could be known much earlier if the equipment was tested on ground a little better.

They are certainly expensive, but this is not a problem. They are bulky and restrictive.
Before Soyuz-11, when the cosmonauts were flying in sportsuits, the capsule had 3 seats. After they put them on, it became 2-seat.
Later, in 1990s, it became 3-seat again by voodoo magic like seats oriented like fan blades and a pit stamped out in the cabin floor.

Tunnels and hatches should be wider, etc.

So, not that the suits are evil, but are they really needed, looking retrospectively.
Except Soyuz-11 with its defects, they could help in no other troubled flight happened irl.

Edited July 29, 2020 by kerbiloid

[RCgothic]

2 hours ago, kerbiloid said:

  

In 1950s.

Still no spaceship ever damaged by a micrometeorite.

If the meteoroid hole is big like in Columbia, they are anyway doomed.
The capsule can't reenter, and a rescue ship is just a dream. And anyway, without the pressurized hull they have just 2 hours of breathing in suits. Just 1 orbital turn, absolutely no rescue ship could help.

Spaceships are frequently struck and damaged by micrometeoroids. The punctures are tiny and not necessarily structurally critical. 1.25 orbits is absolutely long enough to abort safely if necessary.

Edited July 29, 2020 by RCgothic

[kerbiloid]

10 minutes ago, RCgothic said:

Spaceships are frequently struck and damaged by micrometeoroids. The punctures are tiny and not necessarily structurally critical.

Yes, but they are exactly "micro-". They make glasses blurry, but they don't pierce the hull.

[RCgothic]

There are plenty of pics of impact craters in the hulls of spacecraft of varying severity.

 

No Micrometeoroid has yet pieced the hull is the same logic that NASA was using when it ignored o-ring burn-through on cold days and foam falling from the external tanks.

[kerbiloid]

14 minutes ago, RCgothic said:

There are plenty of pics of impact craters in the hulls of spacecraft of varying severity.

 

No Micrometeoroid has yet pieced the hull is the same logic that NASA was using when it ignored o-ring burn-through on cold days and foam falling from the external tanks.

Ok, then we should put expendable armor plates on the capsule and jettison them on re-entering. ^*)

Otherwise what do you suggest against possible micromeorite making a fist-sized hole in the hull? Should we just hope it never happens?

***

The Challenger analogy is clearly false here.
They should postpone the launch and check the SRB after the obviously inappropriate conditions. It's an on-ground procedure.

About Columbia I don't exactly know: was that foam frozen lower than usually or what. I.e. could they presume that before launch.

And in both cases suits wouldn't help.

***

^*) Do not get me wrong, I'm all for it, as well for anti-meteorite blasters and other cute sci-fi stuff.

Edited July 29, 2020 by kerbiloid

[RCgothic]

Challenger is appropriate. Burn through was noted on previous flights, but because it hadn't yet led to disaster no precautions were taken.

On Columbia, foam had been noticed falling from the earliest missions and even critically damaged Atlantis in STS-27, and yet no mitigations were taken.

The risk exists, and it's been noted. Pressure suits are a reasonable mitigation. Armour plating is clearly not a reasonable mitigation for a number of objections.

Edited July 29, 2020 by RCgothic

[DDE]

15 minutes ago, RCgothic said:

Armour plating is clearly not a reasonable mitigation

Spoiler

For you.

 

[mrfox]

Its about the cost vs benefit trade-off of risk mitigation - how much are you giving up by wearing the suits vs the potential risk mitigated with the suit.

The challenger analogy in this case is rather apt - not in terms of o-rings and launch rules, but how the entire shuttle was designed without a LES in the first place - using reasoning similar to what you are trying to present here.

[Guest]

On 7/29/2020 at 10:07 AM, kerbiloid said:

Otherwise what do you suggest against possible micromeorite making a fist-sized hole in the hull? Should we just hope it never happens?

Spacecraft can dodge MMOD that big, because they can be tracked from the ground. ISS occasionally does this. Debris that big are visible on radar and easy to avoid.

[Terwin]

On 7/27/2020 at 11:17 PM, kerbiloid said:

Exactly 0 (zero) rescue missions have been ever performed or even seriously prepared.
Exactly 0 (zero) rescue ships ever stayed on launchpad ready to start.
Exactly 0 (zero) unplanned dockings have been ever performed, including exactly 0 (zero) rescue dockings.

Driving my car to and from work ~250 times a year for ~20 years I have had 0 instances of accidents where my life was saved by my seat-belt.

I have also had 0 instances where the 'windshield breaker' I keep in the center console has allowed me to escape a vehicle when otherwise trapped.

I strongly expect I have spent more time driving my car than there have been maned launches/landings(the times when those suits are worn)

Yet, I always put on my seat-belt every time I get in the car.

Am I expecting to get int an accident?   

No, but I know that it is a plausible outcome of getting into my car, so I put on my safety gear, just in case.

I know for a fact that there have been accidents in the past where a seat-belt/pressure suit would have saved lives.

 

The arguments by the original poster sound to me a lot like the arguments from people saying that they should not be required to wear seat-belts, except coming from car manufacturers who don't want to install the seat-belts in the first place. 

 

329 manned missions (https://en.wikipedia.org/wiki/List_of_human_spaceflights)  8.5 min to orbit, 20 min to reenter

329*(8.5+20)=9376.5 minutes  

9400 minutes /40 minutes(20 min each way to/from work) = 235 days of driving to work...

So yes, every year for the last ~8 years I have spent more time on the road than manned missions have spent launching and landing in total.  Yet I still wear my seat-belt every day.

 

Edited August 3, 2020 by Terwin
launch/landing times

[kerbiloid]

1 hour ago, Terwin said:

Yet, I always put on my seat-belt every time I get in the car.

Does your seat belt decrease the car capacity from 3 to 2 without deforming?

Why not additionally put ejections seats just in case, aren't they are useful in anything flying?

Why is the ship not protected from orbital scrap and meteorite damage with armor plates?

[Superfluous J]

17 minutes ago, kerbiloid said:

Does your seat belt decrease the car capacity from 3 to 2 without deforming?

Then 3 people could die!

[kerbiloid]

9 minutes ago, Superfluous J said:

Then 3 people could die!

They could die from reasons requiring an ejection seat, scuba gear, or armor plates.

The scuba gear would be useful at least twice (Soyuz-23 and onne of Mercuries), i.e. twice as often than spacesuits (Soyuz-11). But do they have scuba gearss?

[Guest]

They have life jackets and other equipment for survival at sea. SCUBA is for diving, if the capsule sinks, you just need to hold your breath until you make it to the surface, aided by your flotation device. Same as you do when escaping a sinking ship. 

Also, spacecraft have armor plates. Just very light ones: 
https://en.wikipedia.org/wiki/Whipple_shield

Edited August 3, 2020 by Guest

[kerbiloid]

1 hour ago, Dragon01 said:

They have life jackets and other equipment for survival at sea. SCUBA is for diving

Yes, Soyuz-23 was overturned in cold water covered with snow, so they exactly needed scuba gears to escape.

That was the only Soyuz flight when one of the crew members was a professional diver (a deep diver). But they didn't have diving equipment.

[Terwin]

9 hours ago, kerbiloid said:

Does your seat belt decrease the car capacity from 3 to 2 without deforming?

My insistence on individual seat-belts reduces vehicle capacity from 7+ to 5, so more-or-less, yes.

The biggest difference between a space-suit and a dry-suit is the hook-ups.  A dry-suit only needs an air-tank and some weights(otherwise you float), a space suit generally also has cooling capacity and you do not usually carry air tanks around on your back(you hook into the vessel for that).  The only things they need for underwater operation are a mobile pressurized air tank(very heavy) and a bunch of (usually lead) weights to cancel buoyancy(very very heavy).  On the other hand, US manned spacecraft make a controlled reentry, and either land at an airport(shuttle) or at sea(capsules).  So long as they avoid the ice-caps, getting frozen in place is not a realistic threat.  Mechanical failures on the other hand, are a viable potential threat and some of those failure modes can b mitigated with a space suit.

 

Unless you want to argue that large chunks of low-latitude ocean are prone to icing up suddenly and unexpectedly...

9 hours ago, kerbiloid said:

Why not additionally put ejections seats just in case, aren't they are useful in anything flying?

Not really no.

Orbital space craft spend so little time at speeds and altitudes where an ejection seat could be useful, that a large net near the launch site could probably cover just about the same set of contingencies as ejection seats. (and launching over the ocean with recovery boats in-place works almost as well as a large net)

Furthermore LES cover the entire ejection seat regime and then some.

[Guest]

4 hours ago, kerbiloid said:

Yes, Soyuz-23 was overturned in cold water covered with snow, so they exactly needed scuba gears to escape.

No, scuba gear would not have helped them. Watertight, insulated overalls would have, of the same sort sailors wear when sailing in very cold waters. FIY, SCUBA stands for "Self-Contained Underwater Breathing Apparatus". That's all it is. Breathing is usually not a problem, surviving in cold water is. And it is a problem that we know how to solve, because this problem is not exclusive to spacecraft, but to anything that is on or over water in cold weather. Besides, Soyuz capsule can float (not on the surface, but slightly under), so the safest way of handling such an emergency is to stay in the capsule and wait to be rescued. Which they did. This, in fact, is better than what sailors and pilots have, because if you fall overboard in cold water, you will not survive for very long even with the right clothing, and climbing aboard a life raft usually requires getting into water first. 

I don't know if Soyuz carries a life raft, but I think Apollo might have had it. Even aircraft ejection seats usually have a small one that unfolds after ejection. Either way, it's the standard way of dealing with such problems.

Edited August 3, 2020 by Guest

[kerbiloid]

49 minutes ago, Dragon01 said:

No, scuba gear would not have helped them. Watertight, insulated overalls would have, of the same sort sailors wear when sailing in very cold waters.

Indeed... But they had neither.

Edited August 3, 2020 by kerbiloid

[Guest]

Yes, because the Soyuz capsule is its own life raft. It is an enclosed, watertight space in which the cosmonauts can survive long enough for help to come. It's also far stronger than any inflatable life raft and most lifeboats you are going to get at sea. The emergency procedures for that kind of situation worked exactly as they were supposed to. Of course, had the capsule been leaking, it would have been a different story, so it probably should have some kind of cold weather (including cold water) survival equipment, just in case. Just like the Shuttle should have had some form of LES.

Edited August 3, 2020 by Guest

[magnemoe]

2 hours ago, kerbiloid said:

Indeed... But they had neither.

The space suits should be pretty water prof. At lest the SpaceX ones looks like they have some padding. However they has intakes for air and cooling who don't work well in water. Still with some covers they could be converted. 
Think it was one of the mercury astronaut who was swimming around in his space suit, but this was from an TV series so might not be true. 

[kerbiloid]

They should be waterproof, but it took all night long and almost cost the crew, several rescuers, and helicopter. One of the crew was reanimated, another one almost should be, too.

So, the spacesuits gave nothing for them, but the mentioned underwater suits or ejection seats (before the capsule reached the lake) could help much better.

The emergency procedures didn't work as they were supposed , too, at least because the rescue team leader forgot the equipment on the base, and because the helicopter was pulling the capsule with wet parachute across the water with engine ready to fail and kill them all.

[magnemoe]

3 hours ago, Dragon01 said:

No, scuba gear would not have helped them. Watertight, insulated overalls would have, of the same sort sailors wear when sailing in very cold waters. FIY, SCUBA stands for "Self-Contained Underwater Breathing Apparatus". That's all it is. Breathing is usually not a problem, surviving in cold water is. And it is a problem that we know how to solve, because this problem is not exclusive to spacecraft, but to anything that is on or over water in cold weather. Besides, Soyuz capsule can float (not on the surface, but slightly under), so the safest way of handling such an emergency is to stay in the capsule and wait to be rescued. Which they did. This, in fact, is better than what sailors and pilots have, because if you fall overboard in cold water, you will not survive for very long even with the right clothing, and climbing aboard a life raft usually requires getting into water first. 

I don't know if Soyuz carries a life raft, but I think Apollo might have had it. Even aircraft ejection seats usually have a small one that unfolds after ejection. Either way, it's the standard way of dealing with such problems.

Scuba gear is nice then you prepare to dive down a bit. you have cold water survival suits who is basically very insulated dry suits with build in life jacket. 
They are mandatory flying out to oil platforms in the north sea as helicopters can go down, now the helicopters has their own inflatables but in rough sea they will flip over. 

One of the qualifications required to work on an platform is that you get tilted up upside down underwater inside an helicopter mock up and has to get out. 
The escape pod qualifications is more fun.

 

 

[kerbiloid]

57 minutes ago, magnemoe said:

Scuba gear is nice then you prepare to dive down a bit.

They had about an hour before getting unconcscious.