Dragon v2 or Orion

[Kryten]

*(not totally sure about that, but certainly not that labour-intensive because they just don't have the people)

They have three and a half thousand people, they're about the same size as ULA.

[Rune]

They have three and a half thousand people, they're about the same size as ULA.

So many already? Well, I suppose if you are churning out 10 cores every year, and gearing up to 40 while you build a new spaceport, you would need quite a decent amount of people. It doesn't compare badly to using the same amount of people to launch 13 EELV's last year... until you factor in that's all that ULA does. They certainly don't have an ISS cargo carrier, or a new rocket and manned capsule on the works. And the day they build a launchpad on their own dime, I'll eat a hat. Promise. Ok, maybe not, because those kinds of promises look douchy to me. But you get my meaning!

Rune. I wonder what ULA's future, as a company, is... will their mother companies pick the pieces afterwards?

Edited June 3, 2015 by Rune

[Kryten]

ULA have been forced to keep up production of two entirely unrelated boosters by AF requirements. The effect on employee numbers is about what you'd expect.

[Rune]

ULA have been forced to keep up production of two entirely unrelated boosters by AF requirements. The effect on employee numbers is about what you'd expect.

That is a valid point. It does give a proper, understandable reason for their elevated cost. Not enough in and of itself, but yeah, I appreciate there are reasons for things being what they are, and theirs cost per kg about twice of most competitors, and nearly four times higher than the lowest bidder.

Rune. Still, OT as hell, so let's just leave it as that.

[Beowolf]

o how is Orion "built" for BEO in a way that is meaningfully different than D2? (aside from the interior being wallpapered with billions of pork dollars).

Orion has a bathroom. Dragon doesn't. That's a pretty meaningful difference, when your flight extends beyond a few hours.

[tater]

I asked that way up the thread, actually. That's quite meaningful from a duration standpoint.

i just checked and it is described as like a camping toilet, and a unisex relief tube. Not really a bathroom, but better than zip bags.

Edited June 4, 2015 by tater

[K^2]

Orion has a bathroom. Dragon doesn't. That's a pretty meaningful difference, when your flight extends beyond a few hours.

Apollo 17 was nearly two weeks long. Do you recall toilets on LM? Sacrifices, they have to be made.

Things like extra radiation shielding, extended life support, and larger heat shield, on the other hand, are going to make a drastic difference in safety of the expedition.

[Bill Phil]

Apollo 17 was nearly two weeks long. Do you recall toilets on LM? Sacrifices, they have to be made.

Things like extra radiation shielding, extended life support, and larger heat shield, on the other hand, are going to make a drastic difference in safety of the expedition.

True. That's why they're putting it in Orion. The astronauts commented on how uncomfortable it was, or something like that. They then tested a space toilet on Slylab. At least, that's what I remember.

[tater]

I asked a female astronaut I spent some time with the biggest engineering challenge, and she said "plumbing for female astronauts," lol. They basically use a negative pressure toilet. I can only assume that the camp toilet in Orion has this capability (think about it). It ls a plus, but we're talking about a square meter and a curtain here, presumably not hard to add to any craft (again, I think the OP should have included CST-100 as well, since I think both of the LEO craft in play could be altered to meet most realistic Orion uses).

Pick a real mission, then explain why it needs a---what is the total Orion/SLS cost to date, 18 billion?---huge, expensive system. ARM and other cislunar stuff just needs to get to the stable lunar orbit in question, or a libration point, whatever the plan is. That's a few hundred m/s if time is not much of an object, or several hundred if you don't want the crew to dilly-dally in transit to and from (many good reasons for this). That's all about the SM, and any of the 3 can have a good SM with some dv in the bank. If a hab is part of the plan, then any of the 3 are fine, and really any of the extended duration benefits of a capsule disappear, as the tab will do the LS, and the capsule is a taxi. The crew can use the hab OTW, and leave it (making return transit time important), or they can dispose of the tab, and dump it ahead of reentry. All 3 craft could do this.

Mars? Not really worth even talking about, frankly. Orion cannot even reenter from the ARM mission without alterations. Realistic BLEO missions are cislunar for the foreseeable future. If any of the 3 are best for the only time they would really be used on a Mars mission, taxi to the real vehicle, then earth reentry, then sure, they get used. I'd like to see that someday, but I honestly think I'll be dead first.

[K^2]

Well, sure, Orion's budget is overblown. That's WHY we have contracts for Boeing and SpaceX to build "cheap", reliable rides. And yeah, I'm sure given the budget and time, either one of these could have built a better capsule than Orion for less.

But you still can't just take Dragon 2, give it a good boost, and wish it luck for a month-long BEO mission. It doesn't have life support for that sort of duration. It doesn't have room for such life support. Sure, that stuff can probably ride in an extended service module, and you can probably patch it into the main systems of the capsule. And you can probably have some sort of flexible hoses in the dragon capsules to collect human waste. You can add thicker walls for radiation protection. You can buff up the heat shield...

Problem is, at that point, you're starting to approach costs of building a capsule that was meant to have all these things from the start, and nowhere near the safety of one. Each of these "upgrades" is additional points of failure. Systems that are either poorly hooked up or lacking redundancies because they are afterthoughts.

This is a bad idea all around. Sending Dragon 2 to BEO would be like the sort of things Soviets did with Voskhod missions in the mid-60s. And then, they had a reason for it, at least. There is no good reason to try and make Dragon 2 do something it's not meant to do. It's a good, safe (presumably) orbital shuttle. That's what it should be used for. And Orion is a big money sink, but BEO missions is what it's meant for, and what it really can do quite successfully when it gets finished. There is no reason to interfere with that. Would it make more sense to wait a few years and then start a contract with a private company, like Space X, for a proper long-duration capsule? Maybe. There's no guarantee that a reputable company would take such a contract right now. Money for Dragon 2 flights won't dry out for a while. Money for Orion could be canceled at any moment. Few companies would take that risk. So it costs us more to do it this way, but it's getting done.

[Rune]

As I said, yeah, I get why Orion is designed as it is designed, it's a perfect capsule to do LOR/cislunar missions "on the cheap" (i.e: only a capsule +lander for landings, just the capsule for orbital missions, all launched directly by the booster). The problem is, that doesn't extend to anywhere else! A simpler capsule with the same beefy heatshield requires an extra module to handle the habitation/airlock/redundancy needs, so it would make the immediate missions more expensive on account of an extra "logistics" module, but then the same capsule would be applicable to any other mission that comes afterwards, or in the meantime. Building Orion just seems a bit like like a one-off effort, that will again be abandoned once NASA gets into the Next Big Thing. I'd rather have a capsule that 50 years later, is still in service and going strong, probably replaced by upgraded versions of itself. A good design that lasts.

Rune. Soyuz is a tad primitive for that, but probably the best example of R&D return on investment to date.

Edited June 4, 2015 by Rune

[Kibble]

Building Orion just seems a bit like like a one-off effort, that will again be abandoned once NASA gets into the Next Big Thing. I'd rather have a capsule that 50 years later, is still in service and going strong, probably replaced by upgraded versions of itself. A good design that lasts.

Why couldn't we have lasting Lunar infrastructure based on Orion?

[tater]

K^2, you'd push a small hab module for a month long mission, no need to buff the taxi. Orion is not built for BEO missions, only BLEO, it needs to be upgraded for BEO, and likely even anything other than straight lunar (according to LockMart themselves).

I'm unclear on what if any shielding Orion actually has. We are talking cosmic rays, and that means water, or hydrogen (could be the H in plastics). It has to be plastics, but I'd like to see the thickness/mass. That is it for radiation protection, it's not that complicated---add hydrogen rich plastics. Electronic protection has 2 options, Orion uses one, which is clunky ICs that can eat cosmic ray hits. SpaceX and others use use smaller feature computers, but have redundancy and error checking. Maybe they could chuck an old PowerPC based laptop as a backup . I'm unsure what Boeing did with CST-100.

[Rune]

Why couldn't we have lasting Lunar infrastructure based on Orion?

You could, of course. It just wouldn't be applicable to anywhere else with the same efficiency, so you would be paying the price in the rest of your missions, including those to LEO.

K^2, you'd push a small hab module for a month long mission, no need to buff the taxi. Orion is not built for BEO missions, only BLEO, it needs to be upgraded for BEO, and likely even anything other than straight lunar (according to LockMart themselves).

I'm unclear on what if any shielding Orion actually has. We are talking cosmic rays, and that means water, or hydrogen (could be the H in plastics). It has to be plastics, but I'd like to see the thickness/mass. That is it for radiation protection, it's not that complicated---add hydrogen rich plastics. Electronic protection has 2 options, Orion uses one, which is clunky ICs that can eat cosmic ray hits. SpaceX and others use use smaller feature computers, but have redundancy and error checking. Maybe they could chuck an old PowerPC based laptop as a backup . I'm unsure what Boeing did with CST-100.

It has all the shielding a paper study on radiation dose distribution in the cabin and some subsequent equipment rearrangement can provide. They may have changed a few liners with lighter plastics too, but weight and fire-hazard implication leave LockMart very little room to work with.

Rune. Which is to say, pretty much nothing at all.