In the wake of the Potemkin abort test of Orion, Eric Berger has a reality check.
[Update a few minutes later]
This is a perfect example of the problem:
Even as NASA needs to be spending money on a lunar lander, it has been directed by Congressional authorizations to spend more money on the SLS rocket. To that end, NASA announced last week a $383 million cost-plus contract to build a second mobile launcher, to be used for the Block 1B version of the Space Launch System rocket, which has a more powerful upper stage. This rocket is at least five years away from launching, will cost billions to develop, and is not currently used in any of NASA’s plans for the 2024 landing.
As Bob Zubrin often says, they don’t want to spend money to do things; they want to do things to spend money.
[Update a few more minutes later]
Think of how quickly we could get crews back with this abort profile!
https://twitter.com/ChrisG_NSF/status/1146049069636304896/photo/1
Look at the Youtube video of the impact, the Orion hit the water with more backspin than a Jack Nicholas bunker shot. Obviously it lacks subsonic aerodynamic stability.
In comments, Eric Berger mentioned that the Dragon 2 explosion wasn’t caused by the Super Dracos, but didn’t say anything more.
The parachutes provide landing stability. AA-2 was not testing landing stability, so there were no chutes. This is not a surprise, and it’s also not a failing.
I understand the urge to dump on Orion and/or SLS every chance some of you get, but come on. The test did exactly what it needed to and validated the requirements assigned to it. I would heartily agree that it took too long to get to this point, but AA-2 was a fully-successful test of precisely what it was supposed to test.
It was, but it remains a waste of money.
Was this the same AA-2 transonic abort test that was supposed to be ready in the late fall of 2011 and fly in early 2012?
2008 Orion schedule
If so, is there still a PA-2 pad abort test to complete?
I believe that remains to be seen. It certainly took too long and is almost certainly more expensive than it needed to be because of the delays themselves.
However, my point still stands: An successful ascent abort test of the Orion system was needed, and that happened yesterday. Making snide comments about performance measures that the AA-2 was never meant to address and was not designed to meet, it borders on petty.
I was just surprised that it tumbled so rapidly. I didn’t even know the capsules were aerodynamically unstable. I assumed they kept the CG well below the CP even in the subsonic regime.
Looking at the video, it was quite stable at 2:47, then slightly wobbly 8 seconds later, at 2:55, and then pretty wobbly by 2:58. At 3:14, 27 seconds after 2:47, it’s really wobbly, and by 3:22 (35 seconds into it), it’s tumbling at 100 RPM. Over the next two seconds the tumble increases to about 115 RPM (1.87 revs/second) and seems to maintain that rate till impact at 3:38, so it made about 28 to 30 revolutions in total.
I found that kind of interesting.
Craig, you sound impressed by a test of an escape device identical to one I saw on a rocket 50 years ago this month. Are we supposed to marvel that this re-enactment of an old system was a success?
Those weren’t steerable abort systems. The top of the Orion’s LAS has steering motors that can control its trajectory during an abort.
There are only a few reasons I can think of to require that.
If Orion somehow supposed to be able to detect and avoid a collision with a pair of rampaging SRBs.
If they want to guarantee an ocean landing for a pad abort and the SLS has to go through a fast early roll maneuver, so that Apollo’s simple pitch motor arrangement (they either fire it or they don’t) wouldn’t be adequate.
If there’s a potential attitude instability that must be damped.
It’s too nifty not to do it.
However, it adds weight because they have to burn the attitude control motor whether they need it or not, sending the exhaust out opposite sides if no adjustment is needed.
Apollo had a horizontal motor in the LES, but I forget what environment it was for. And canards to turn the capsule around in some flight regimes.
Maybe the motor was for a higher-altitude abort where the canards wouldn’t work?
The horizontal motor was called the pitch motor, and it’s job was to pitch the capsule eastward in an abort from the pad or the early part of the launch (perhaps the first half minute?). Once the rocket was headed out over the ocean, guaranteeing a water landing, the pitch motor was disabled.
I assume the SLS will do a rapid roll after launch due to the same launch pad orientation issues the Shuttle had, in which case a simple pitch motor wouldn’t stay correctly aligned. With a simple rotation of the top of the abort tower, they could keep it sufficiently aligned through the roll (all they have to do is simply miss Florida), since the roll is always going be executed the same way at the same time.
That would add moving parts (shaft, bearings, drive mechanism) that would have to withstand high applied forces), so perhaps the multiple valve system seemed easier. Or they really felt they needed maneuverability.
No, not marvel. I’m just saying that going the other way and being critical of a performance factor not even remotely planned in the test itself is just as foolish.
Am I happy that the test went so well? Yes.
Am I happy that I can walk over to JSC and see a booster just like what was used during Apollo for essentially the same test before I was born? No.
It’s not quite that bad. The Mercury and Apollo LAS look like they were designed by civil engineers. The Orion LAS screams “High speed low drag.” 🙂
Even though it’s probably the least optimal way to build a LAS (the weight is sufficient to protect the capsule with a circular steel plate as thick as the frontal armor of a Sherman tank) and even though it might murder an innocent baby whale when it comes down, it is at least steerable and streamlined.
However, I’m wondering, is the Orion capsule that aerodynamically unstable, to the extent that it might wrap itself up in its shroud lines on a delayed drogue deployment, or did they move the CG forward to ease the abort separation test conditions?
I have no idea. Maybe all re-entry capsules kick into an uncontrolled tumble if the drogue doesn’t make it out in time. Other times a test passed with flying colors answers a question that nobody was asking. It might slightly nag at me until I run across some old hands who reassure me or somebody else that tumbling end over end at 115 RPM is perfectly normal for a re-entry vehicle. I just haven’t seen that before, and can’t recall reading about it.
It was a test that revealed a serious, fatal design flaw. Honestly, this reminds me of that cartoon with the dog in the burning house saying “this is fine”.
With that rotation rate the drogue will wrap around the capsule and not deploy properly. The center of mass is too far from the blunt end of the capsule. They’re going to have to do a complete redesign.
I doubt they screwed up on the real Orion. I’m guessing that since it was just an abort test, they didn’t feel the need to exactly replicate the real capsule, just its overall weight.
All they might have needed was to verify the aerodynamic loads during a supersonic separation and abort burn, along with testing the abort, steering, and separation motors.
So they’d want to gather data on Cd, Cl, and Cm vs alpha and beta, and would probably want to have the data extend past the normal margins for maximum pitch or yaw angles. One way to do that would be to make the Orion too nose heavy so they can pitch or yaw and still recover, past the point they’d normally be able to with a flight-worthy CG location.
At least, that’s the story I’d go with. ^_^
It could be they were just cheating to make the test easier. 🙂
I’m assuming they knew things would go all pear shaped because NASA’s coverage didn’t show the capsule’s continued descent. Perhaps that’s because they couldn’t find a single NASA commentator would would agree not to holler “Splashdown!” when it impacted, but I’ll bet it’s because they knew it was going to get ugly.
The good/bad thing is that they are doing both. It isn’t sustainable but isn’t in danger of being cancelled by congress either.
I watched it live, but I’m curious how much that test cost compared to, say, a Falcon Heavy launch. SpaceX’s website still says $90 million for the latter.
Consider the Orion vehicle tested Tuesday; NASA originally sought bids for the development of the deep-space capsule that would become Orion all the way back in March 2005.
This is what amazes me. I used to work at Lockheed Martin, on the floor where the CEV bid was put together. A few years later, I left LM to go to work on the Space Shuttle Program. When the Shuttle Program ended and I left NASA. That was eight years ago.
Now, on the 50th Anniversary of the first landing on the moon; NASA will have no means of its own to lift a human into orbit.
NASA has the means (Falcon 9/Dragon 2); it just chooses not to use it.
They didn’t build it.
The Air Force doesn’t build F-35’s either but nobody says Locheed Martin is the one flying the sorties.
Here’s a clue. Catch it.
Rand, one of the criticisms of this launch abort system is it weighs too much, and robs performance just by its existence. To overcome that drag on overall performance, could you fire the abort rocket once it is no longer required to return that energy to the ascent?
You could with Dragon, but not with a tractor system. It is completely dead weight on a nominal mission. Plus it adds a hazard if it fails to jettison, which basically means dead crew.
Gateway just does not make sense.
Okay, the SLS/Orion architecture can’t do LLO and return, not enough delta/v in the service module. I get that. But, how, exactly, would a space station in a distant retrograde elliptical lunar orbit help with that?
If you have a lander that has the delta/v to do a mission from there, it can easily do one from a lunar orbit that Orion could reach (and you don’t need the space station).
Why not just stretch the fucking command module on Orion or let the third stage provide the LOI?
I think the root problem is that Orion’s specifications were set back when they planned to fly it on top of Ares V, which had a significantly higher LEO payload capacity than SLS, and thus enough delta V to get Orion to LLO and back. The SLS would be fine if they had a lighter capsule, but they’ve already spent many years and many billions on both programs. Thus Asteroid Redirect and Lunar Gateway.
I don’t think SpaceX, Blue Origin, or any other commercial venture would remain committed to such a mismatch, at least not for long.
The quickest way to patch the delta V deficit might be to have Orion dock with a commercially launched booster stage in LLO, then use their SLS upper stage for LOI of both Orion and the extra booster, and use the commercial booster for lunar capture and dropping into LLO. However, I haven’t done any math on it.
Given their strung out schedule and the rate at which commercial space is moving toward lunar missions, it might be a moot point.
The Hydrogen-fueled LM was originally supposed to brake the stack into LLO.
Again, why not just stretch the SM for longer hydrazine tanks or let the Block 1B upper stage do the orbit insertion? There are other solutions besides the gateway. And if you want a gateway, I bet you could lease one from someone like Bigelow for a shit-ton cheaper than building it to NASA spec like ISS.
The block 1b upper stage, modified to give it the 3-day duration time needed, would IMHO be your best bet.
The problem IMHO with stretching the Orion SM is you need to basically at least double the delta/v, which means increasing prop by roughly 4x. Quite a stretch.
The easiest way to give the stack the needed delta/v is IMHO swap the Orion for a Crew Dragon; the much lighter Dragon with the Orion SM would have the needed delta/v.
Gateway does make sense if you look at performance rather than promise of past launch systems. ISS now orbits higher than it did when STS serviced it. Why? SLS will not have the ability to get to the moon and back un-aided. Why? NASA drags their feet when told to go somewhere. Why? The stepping-stone approach of lunar gateway makes sense if the equipment you are forced to use lacks the capability to get where you are told to go.
At the last Moon Village Association meeting, I got a chance to met with Scott Pace one-on-one for 20 minutes. I gave him a document that I wrote arguing that a commercial, direct, return-to-the-Moon transportation system (aka “Lunar COTS”) would be particularly useful to open the Moon for lunar exploration. But I also made the broader case that the Gateway wasn’t technically needed to get to the Moon and that a cost-effective transportation system would achieve a much greater historic legacy as it would result in America leading the way in opening the Moon to a sustainable present leading to settlement.
Scott Pace asked how even the $1.2 B Lunar COTS could be paid for and I suggested plussing up NASA’s budget. Scott himself actually came up with the rationale for greater funding being that, of returning to the Moon in a sustainable way was sufficiently compelling then the additional budget could be justified.
But then Scott did something that I wasn’t anticipating. Instead of taking my message to Pence who I thought should know about the historic opportunity. But Pace instead asked for another copy of my document imdicating that he wanted to give it to the OMB. At the time I didn’t understand why because the OMB doesn’t set policy — or does it? Apparently, OMB does play an influential role with policy.
Here’s an interesting question-set: Suppose Trump is defeated in 2020 and the Democrats keep the House and retake the Senate. Suppose there’s a socialist in the White House and Progressives controlling Congress. Call it “Destroy All Monsters” time. With heavy anti-Musk sentiment from both the left and right, Progressives decrying his “Billionnaire Boys Club on Mars” ambitions, hated by Wall Street for the crime of Winning… what? Dismember SpaceX and feed it to OldSpace? And then cancel Artemis now that it’s associated with Trump? You say Shelby will never permit it? OldSpace will never permit it? Shelby’s a turncoat turned Republican, and the Dems will never take him back. And Blue Origin is already in bed with OldSpace…
If the Democrats take over the government in 2020, there’ll be much worse things to worry about than whether they attack SpaceX.
I’m not so sure you’re right about that. Famous Heinlein quote:
“When a place gets crowded enough to require IDs, social collapse is not far away. It is time to go elsewhere. The best thing about space travel is it made it possible to go elsewhere.”
I sincerely hope I’m wrong, but it’s beginning to look suspiciously like Elon Musk is the last best hope of mankind. And I won’t be surprised to find out he’s been assassinated one day. I used to think Bezos was our backup savior. Not so much anymore.
The left can’t really go after Musk in any serious way or they won’t get their plug-in cars, plus he used to date Amber Heard. SpaceX and Blue Origin’s constellation of broadband satellites will probably seal the deal and make them indispensable.
If Democrats did win big, I don’t think they’d scrap SLS/Orion (sadly) because they don’t want to look “anti-science”. NASA would just re-emphasize some role concerning global warming and keep on going.
I hope you’re right. I hope I’m wrong. And, of course, other things could happen.
I think expecting the left to be that rational is a low probability idea. Also, expecting leftist leadership to care whether the leftist voters get electric cars is probability zero. The left’s goal is for hoi polloi to have no cars at all.
It also doesn’t seem to me that the Democrats care about looking “anti-science,” since they think they control the definition of “Science.” Anything they’re against is not “Science.”
Well, that’s where we’ll be glad we didn’t get around to building a planetary meteor defense system.
I would not consider an abort test to be successful unless it is also survivable. Beginning to end. If the requirements didn’t specify that, then the test was a sham.
Perhaps they should have described it as an “in-flight abort motor test” instead of an abort test.
But you’d think $250+ million would pay for a pretty thorough test, considering that enough money for Elon to put two or three Teslas past the orbit of Mars.
They could have saved a lot of money by doing the abort test with a used Orion capsule, like Musk was planning to do.
Oh, wait.
Ha!
I’m guessing the external volume of the Orion is about 1,000 cubic feet, which would give it a density of about 23 lbs/cubic foot. If they built the boilerplate capsule out of western red cedar, all glued and screwed together to form a solid shape and then chucked in a big lathe for finishing, they would have a reusable test article that they could probably slam into the ocean as often as they wanted.
“I used to think Bezos was our backup savior. Not so much anymore.”
I think that for Bezos, space is just an amusing hobby. Not all that much drive or urgency is evident and he seems intent on making money, which he doesn’t need, via old space. A huge disappointment.
Musk has demonstrated that the build, test, fly, redesign, rinse and repeat rapidly paradigm works.
I still think the electric car/save us from global warming thing is stupid though.