The Apollo Project

[alpha tech]

I have a question for the community,

during the late 1960's and early 1970's NASA built a moon rocket.

it composed of a Command and Service Module, a Lunar module, and a transfer stage.

Why were the command modules never reused, it would have saved money and time.

and if I misspelled anything please forgive it its just spelling.

alpha tech

 

[Gaarst]

They were simply not made to be reused.

Reusing stuff that goes to space is hard. This is one of the reasons why SpaceX doesn't fly its recovered boosters and why the space shuttle was such a waste of money and time.

Here we're talking about a pod that reenters from lunar orbit (so much faster than anything from LEO, 11km/s vs 7.8km/s) made of aluminum sheets so thin the astronauts could puncture them if they hit it a bit too hard. Refurbishing an Apollo capsule would probably be more expensive than making a whole new one, so would modifying them so that they could be reused more easily.

Even if they were reused, there's a 3000t rocket below that could not be reused, so you'd save at most a couple millions per launch out of $100 billion the Apollo program cost.

[alpha tech]

19 minutes ago, Gaarst said:

Even if they were reused, there's a 3000t rocket below that could not be reused, so you'd save at most a couple millions per launch out of $100 billion the Apollo program cost.

 I thought the research costed the billion dollars, but the rockets were only like 500 million or more

or at least salvaging what is still of use in the command module like the computers and the electrical components

Edited December 1, 2016 by alpha tech

[Ten Key]

14 minutes ago, alpha tech said:

I thought the research costed the billion dollars, but the rockets were only like 500 million or more

Ah, but that's part of the problem too. Most of the expenses incurred during Apollo were payroll costs-- reusing the capsule doesn't help with that. And, depending on how much time and effort is required to get the capsule ready for a second flight, reusing it could actually make the costs go up. 

[Gaarst]

26 minutes ago, alpha tech said:

 I thought the research costed the billion dollars, but the rockets were only like 500 million or more

or at least salvaging what is still of use in the command module like the computers and the electrical components

Still a negligible fraction of the overall cost. Even more so if the research cost a lot more than the hardware.

And you would need to test all the salvaged parts even more than if they just came out the factory, which will make you spend the few bucks you saved by recovering them.

 

Edit: I really need to read the posts above mine. I basically said the same thing as Ten Key. 

Edited December 1, 2016 by Gaarst

[Nibb31]

Reuse isn't always cost effective. If you have a party at your house with 50 guests once a year, it will be much more economical to buy disposable cups and paper plates and not spend two hours to do the dishes. For a restaurant that serves 50 people every night, it is more economical to use non-disposable plates and to pay someone to do the dishes.

The Apollo CMs were high-tech for the time, but they were pretty much scrap when they came back. The heat shield and back shell were destroyed, umbilicals were cut up, some parts were damaged by pyro events, and the rest had been exposed to seawater. Refurbishing and testing would have been much more expensive than simply building a new command module from scratch, which is what you had to do for the rest of the Saturn V any way. The command modules were only a small part of the total cost of every Moon mission, so it really wasn't worth it.

[alpha tech]

we all know that the space shuttle was a flying death trap, Gemini was intended on using a paraglider to glide to a runway, but was too unstable,

so why did they not land back at KSC instead somewhere in Hawaii.

 

4 minutes ago, Nibb31 said:

Reuse isn't always cost effective. If you have a party at your house with 50 guests once a year, it will be much more economical to buy disposable cups and paper plates and not spend two hours to do the dishes. For a restaurant that serves 50 people every night, it is more economical to use non-disposable plates and to pay someone to do the dishes.

The Apollo CMs were high-tech for the time, but they were pretty much scrap when they came back. The heat shield and back shell were destroyed, umbilicals were cut up, some parts were damaged by pyro events, and the rest had been exposed to seawater. Refurbishing and testing would have been much more expensive than simply building a new command module from scratch, which is what you had to do for the rest of the Saturn V any way. The command modules were only a small part of the total cost of every Moon mission, so it really wasn't worth it.

What about Orion when it gets put into use it like a Apollo command module but newer.

will it be reused or will it be scrap when they get back , also what about the Soyuz doesn't it get reused

[Nibb31]

1 hour ago, alpha tech said:

or at least salvaging what is still of use in the command module like the computers and the electrical components

That would have involved complete disassembly, reassembly, integration, and testing. It is cheaper to skip the disassembly part and just start with a new one.

Also, if you only have one unit of a specific component that you reuse on each flight, what do you do if you find a fault or if you need an upgrade? You need to order another one-off to replace it, and that is super expensive. It is usually more efficient to build a batch of them in order to have a supply line for spares and to iterate improvements.

23 minutes ago, alpha tech said:

we all know that the space shuttle was a flying death trap, Gemini was intended on using a paraglider to glide to a runway, but was too unstable,

so why did they not land back at KSC instead somewhere in Hawaii.

Apollo landed in the Pacific because it required a splashdown area several hundred kilometers wide, without risking to land on hard ground. I suppose they preferred the Pacific rather than the Atlantic because there was typically less traffic. Most of the Mercury and Gemini missions splashed down in the Atlantic, and so did Apollo 7.

For Apollo, the splashdown location was determined by the timing of the TEI burn (Trans-Earth Injection = when the Apollo CSM leaves lunar orbit). Basically, they had to set up the mission so that the TEI burn coincided with an alignment which would bring the CM into the correct place (an area in the ocean) at the correct time (during daytime to facilitate search and recovery operations)

This is a (very old) but great educational video that explains everything you need to know about reentry and landing:

Quote

What about Orion when it gets put into use it like a Apollo command module but newer.

The original plans were to reuse Orion and to make it land in the desert on airbags. Nowadays, that requirement seems to have been dropped and Orion is designed for splashdown, which makes reuse much harder. At this stage, you'll be lucky if it flies more than once or twice anyway.

Quote

will it be reused or will it be scrap when they get back , also what about the Soyuz doesn't it get reused

Nope, they are gutted and scrapped. Some electronics might be reused, but there really isn't much to reuse inside a Soyuz descent module.

Edited December 1, 2016 by Nibb31

[tater]

Salvaging the Space Shuttle Orbiter cost vast amounts of money, increasing the launch costs substantially. Right now, there is zero evidence that reusing anything from a rocket is actually cost-effective compared to investing the dev cost of that into more efficient production in the first place, then disposing of them.

You also seem to forget how much timing mattered. The job was to get it done.

30 minutes ago, Nibb31 said:

Reuse isn't always cost effective. If you have a party at your house with 50 guests once a year, it will be much more economical to buy disposable cups and paper plates and not spend two hours to do the dishes. For a restaurant that serves 50 people every night, it is more economical to use non-disposable plates and to pay someone to do the dishes.

I'm getting ready for a party we throw before Christmas each year for more like 150 people... we still use real glasses, etc. Sure it takes a few hours to wash the dishes---but the dishwasher is a machine, it doesn't care  (heck, it'll run during the party as soon as it's full, too, in case we run out of wine glasses).

Maybe we need to build our rockets with robots, and kill those labor costs...

[wumpus]

Don't forget that the command module went into Lunar orbit.  Only the lunar lander had higher delta-v requirements.  So even adding a heat shield meant that it required more fuel, which meant more fuel+thrust to stage 2, which required more fuel and thrust for stage 1 (which lifted off with a TWR roughly 1.1 and simply couldn't afford *any* more mass above it).  Then there's the mass of the parachutes (just look up the issue of spacex preferring powered landings vs. parachutes to know how much they weigh) and you start to see why this really isn't an option.

Don't forget that JFK announced "We choose to go to the Moon" in September 1962 and Apollo 11 landed in July, 1969.  Adding 6 more months to the schedule would result effectively in failure, and I'm sure NASA was cutting *everything* that wasn't needed off the schedule.  Recovery wasn't needed, wouldn't lower costs significantly (assuming zero extra mass: this is pure fantasy.  It would massively increase costs [thanks to requiring a different design for stage 1] to attempt to return the command module.  Recovery of the F1 engines is far more believable, but probably wouldn't work).

Much of engineering isn't about "doing x".  It is managing the complexity that gets you from here to "doing x".  The whole point of going through Gemini to Apollo 10 was about managing that complexity and proving each part did its thing.  Recovering the command module was unnecessary complexity and wisely dropped.  I would have thought that KSP taught that lesson pretty well (although things like just how badly recovery propagates complexity isn't well modeled).

[tater]

Yeah, if you read Apollo history, you even see the point where the mass at the top of the stack (our tyrannical rocket equation at work) is so critical Grumman starts drilling holes in all the metalwork they can inside the LEM (keeping strength, deleting mass). The Apollo 10 LEM was the earlier model, and ended up too heavy to land and return to LLO. Every kg really mattered.

There is also splashdown and salt water to consider. We have no data on how reusable Orion will be after taking a swim.

[NSEP]

When those capsules where being recovered, the where burnt and stuff.

Reusing Apollo capsules is like uncooking bacon, impossible

Edited December 1, 2016 by NSEP

[Mitchz95]

4 hours ago, tater said:

Maybe we need to build our rockets with robots, and kill those labor costs...

But who's gonna build the robots!?

[Vanamonde]

Additional reasons the capsules were not re-used: 

This was the first (and so far only) time a crewed ship had gone as far as lunar orbit. The capsules would have been studied to see how they responded to radiation and micrometeorites. 

The craft were designed and built over a period of years, so I believe the last one was already made before the first one came back. 

The cost of the capsule, even if fully recovered, would only have been a tiny fraction of building a new rocket, since the rest of the ship was discarded during the flight. It would not have been much of a savings. 

[wumpus]

The tyranny of the rocket equation shows why the only reason for recovering the tip of the rocket is the astronauts themselves.  You would want to start your recovery operations with stage 1, then move on to stage 2 (if possible) and so on [Spacex has given up on recovering stage 2 of Falcon 9].  Somebody did run an experiment where an F1 engine (the main engines of the Saturn V) was dunked in saltwater, but it was at a relatively shallow depth for a brief period of time.

The Shuttle SRBs fell (with parachutes) hit the water at 23 m/s (~50mph) and wound up with ~10m sticking out of the water (which, if it had engines at the bottom meant they would be ~35m down).  The SRBs also have the advantage of naturally floating due to being tube made of solid steel holding a column of air inside.  While the Saturn V first stage might float, it certainly wasn't all that strong for any force other than 3G of force along the prograde axis (presumably it could handle the retrograde forces of the parachutes, but don't count on the impact of the water).  It wasn't going to handle water impact horizontally, and if it did survive a vertical impact it would go deep enough to crush the fuel tanks/rocket body.

Assuming you were only interested in the engines (a reasonable assumption), it would be hard to imagine recovery method that didn't involve them being dunked vastly deeper than that famous test (although maybe you could disconnect them and attach them to some sort of buoyant device quickly enough).  

All this is pretty hypothetical, and wouldn't be seriously considered in the crash course to get to the Moon (and back) before December 31, 1969.  There was a design for a followup of the Saturn V (the Saturn Int-21) and I don't think even it considered reusing any parts.  I'd have to wonder how much final payload it would cost (for Apollos 12-17) to put parachutes on the engine end of the first stage (and thus use the entire rocket as a crumple zone for water impact).

[Jonfliesgoats]

With future advances in manfuacturing and materials we may see reuseable spacecraft come back.  Everylne makes great points about the costs involved, but reuseability seems to be the direction many smart people are moving despite the lessons from the Shuttle program.

Advances in parachute design and control (ram air canopies with GPS guidance) make capsules with precision recoveries much more viable.  We won't see this with Orion, sadly.  

We are still in the very earliest phases of spaceflght (think Montgolfier bros. with manned atmospheric flight).  I am confident we will see improvements in materials, propulsion and process.  We just may not see it in the US due to deteriorating popular will to fly in space.

[Tullius]

2 hours ago, Jonfliesgoats said:

With future advances in manfuacturing and materials we may see reuseable spacecraft come back.  Everylne makes great points about the costs involved, but reuseability seems to be the direction many smart people are moving despite the lessons from the Shuttle program.

Advances in parachute design and control (ram air canopies with GPS guidance) make capsules with precision recoveries much more viable.  We won't see this with Orion, sadly.  

We are still in the very earliest phases of spaceflght (think Montgolfier bros. with manned atmospheric flight).  I am confident we will see improvements in materials, propulsion and process.  We just may not see it in the US due to deteriorating popular will to fly in space.

Reusability will eventually be a thing in rocket design. If the right time has already come, we will see when SpaceX starts reflying boosters.

Reusability is useless for Orion, since it will fly at best once per year. Considering it will be developped further between space flights, there is just point in reusing it. The same with splashing down in the ocean instead of a powered landing: Developping such a system costs time and money, while splashdowns are well known.

[Jonfliesgoats]

Agreed.  I was actually surprised that SpaceX is only showing a 30% reduction in launch cost for their reuseable vehicle.  I can't imagine a booster doing more than a few cycles now.  When we get boosters that can launch thousand of times over, we may see much more significant savings.  Maybe?

[Nibb31]

32 minutes ago, Jonfliesgoats said:

Agreed.  I was actually surprised that SpaceX is only showing a 30% reduction in launch cost for their reuseable vehicle. 

Why would it be more? The manufacturing cost of the first stage hardware is only a fraction of the cost of a launch campaign. The biggest cost is the workforce, not the hardware, and reuse doesn't do much to reduce the workforce, except for some manufacturing positions. 

[wumpus]

1 hour ago, Nibb31 said:

Why would it be more? The manufacturing cost of the first stage hardware is only a fraction of the cost of a launch campaign. The biggest cost is the workforce, not the hardware, and reuse doesn't do much to reduce the workforce, except for some manufacturing positions. 

Apparently that fraction is at least 3/10s.  I suspect that they can get it down if they create their own [unlike NASA] countdown procedures.  I suspect that Spacex might be wishing they hired a few more DC-X alumni (mostly hired by Blue Origin).  While DC-X might not have gotten very far in terms of going into space and especially any SSTO plans, it certainly blazed a trail of low workforce launches.

[YNM]

Reusable space things is hard.

a. They need to still be able to hold the forces even when worn out.

b. They need to reduce wear even with the extreme forces.

c. If they manage to do that, it's only logical when the costs to do so win over the cost to just make a bunch of single-uses.

d. It's never perfect - you still need repairs and overhauls.

If you ever wonder why we haven't make rockets like cars, imagine having your car engine (which are very much well-engineered) running on LH2-LOX and experiencing a few gees. Your standard rocket engine is not going much, much further than that. Similar goes to the body, etc.

The capsules - here's the forces that goes on them :

- G-forces

- Micrometeoroid impacts

- Corrosion (salt water)

- Heat (which, apart from shuttle tiles, we haven't make ones that don't ablate - even shuttle do by a bit)

Edited December 3, 2016 by YNM

[Camacha]

They tried to do something that is terribly hard even today for the first time. It does not really help to add additional constraints and demands. Do it first, then make it more complicated.

[Nibb31]

7 hours ago, wumpus said:

Apparently that fraction is at least 3/10s.  I suspect that they can get it down if they create their own [unlike NASA] countdown procedures.  

Cutting corners is not usually the best way to improve reliability. SpaceX doesn't exactly have a great record for that sort of thing...

What would you think of an airline that offers half price tickets due to the fact that they have designed their own safety and maintenance procedures ?

I'm sure there is room for optimization, but folks in the industry have decades of experience with launching rockets and they are not dummies. Those procedures exist for reasons, and usually lessons that were learned the hard way. You are ultimately handling huge amounts of energy in extreme conditions, so it will never be as mundane as filling up a truck.

 

7 hours ago, YNM said:

If you ever wonder why we haven't make rockets like cars, imagine having your car engine (which are very much well-engineered) running on LH2-LOX and experiencing a few gees. Your standard rocket engine is not going much, much further than that. Similar goes to the body, etc.

Actually, many components on Formula 1 race cars are usually worn out after a race and trashed, including the engines. They have in common that they run in extreme conditions.

 

[Jonfliesgoats]

Reuseability is certainly difficult, but it is the future.  

Similar discussions existed during the dawn of aviation.  Wooden airframes would rot and wear out after just ten years of regular use.  (We are all aware of hangared, flying museum pieces).  The first major airline disaster (I am not including air mail or non-scheduled charters) in the US was due to wood rot.  As engines became more reliable, we went from 50 hour overhaul periods on engines like the Hispano Suiza or Gnome Rotary to 1800 hours on Post-war reciprocating engines  to 7500 hours on the PT-6 (I was trying to stick with smallish propeller engines).  We got away from wooden trusses, learned to hangar airplanes, developed new aluminum alloys and got really good with semi-monocoque construction.  Later we started using composites.

Right now reuseability is very difficult.  We will get there with better diagnostics and overhaul techniques.  Unfortunately, we will learn what we need to learn through expensive losses.  That is another lesson from the early days of aviation, sadly.  Still, we will get there.

[wumpus]

12 hours ago, Nibb31 said:

Cutting corners is not usually the best way to improve reliability. SpaceX doesn't exactly have a great record for that sort of thing...

What would you think of an airline that offers half price tickets due to the fact that they have designed their own safety and maintenance procedures ?

I'm sure there is room for optimization, but folks in the industry have decades of experience with launching rockets and they are not dummies. Those procedures exist for reasons, and usually lessons that were learned the hard way. You are ultimately handling huge amounts of energy in extreme conditions, so it will never be as mundane as filling up a truck.

Actually, many components on Formula 1 race cars are usually worn out after a race and trashed, including the engines. They have in common that they run in extreme conditions.

My assumption was that the practices were established in a mad rush to catch up to Sputnik and Gagarin, and later expanded to reach the Moon.  After that it was "we've always done it this way, and if a failure happens when a change happens, whoever changed it will be blamed regardless of whether that caused it".  My understanding was that the DC-X project made some strides in towards reducing launch costs and *nobody* else has really tried.

Spacex has certainly had to walk back any "gas and go" statements about how falcon 9 would be reused, but that doesn't mean that they shouldn't be looking for ways to make launches cheaper.

Formula 1 is a rather interesting case.  Certainly any wearable item (tires, clutch, brakes) will be replaced.  I'd even expect things like struts, springs and shocks to be replaced as well (they may not be pushed hard compared to normal items, but their weight is likely reduced to the point they can only survive a single race).  There's also the issue that the entire car will only exist for relatively few races (a few seasons, then FIA will change the rules again and everybody builds a new car).  Presumably spacex new some items would wear out before 10 launches (never mind Musk's "thousands of launches" Mars justifications), and they are replaceable and scheduled to be replaced.  I also would be fairly surprised if they didn't discover that some few parts wore more than expected and need replaced.  Probably enough that at least one will be hard to get to.

That reminds me.  Next time I fly I'll pick an airline that does maintenance in the US (at least for US domestic flights).  There's more than a few ways to invent your own cheaper system.