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NASA SLS/Orion/Payloads


_Augustus_

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1 hour ago, tater said:

I think it has been changed a little, but they are still making it Apollo style, by hand. I don't think the fundamental design has changed... I'll have to look and see what I can dig up. 

http://spacenews.com/lockheed-martin-pressing-to-simplify-orion-heat-shield/

The one used on EFT-1 was a single piece honeycomb injected design, like the Apollo heatshield. The new one is made of tiles that are glued on. Basically, it's an entirely different structure, which means that the flight data from EFT-1 is no longer applicable.

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Just now, Nibb31 said:

http://spacenews.com/lockheed-martin-pressing-to-simplify-orion-heat-shield/

The one used on EFT-1 was a single piece honeycomb injected design, like the Apollo heatshield. The new one is made of tiles that are glued on. Basically, it's an entirely different structure, which means that the flight data from EFT-1 is no longer applicable.

So EFT-1 was a complete waste of money and time?

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6 minutes ago, _Augustus_ said:

So EFT-1 was a complete waste of money and time?

Well no, they'll just need to validate the heatshield again. I would imagine that the reentry data they collected on that flight will also have helped them make this change. This is a late program change no doubt, but ETF-1 will still have produced a wealth of data on all other aspects of the spaecraft

Edited by Steel
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19 minutes ago, _Augustus_ said:

So EFT-1 was a complete waste of money and time?

I wouldn't go that far. You always learn something. In this case, they learned (among other things) that the honeycomb designed was overkill, fragile, expensive, and heavy.

However, it also means that the current design will have only EM-1 to prove itself before carrying astronauts. They'd better not find any issues with the new design.

13 minutes ago, Ultimate Steve said:

Not a complete waste, they were testing more than just the heat shield. 

Not really. The EFT-1 Orion was pretty much a boilerplate capsule on an interim launcher, with interim avionics, no ECLSS, and no SM. It really only tested reentry and splashdown. Since then, they have redesigned the heatshield, the parachutes, and the landing bags (which failed BTW). There were definitely lessons learned, which is what testing is all about, but not much of the validation data can be transferred over to the EM-1 Orion.

36 minutes ago, Cunjo Carl said:

I guess I'll go look up the definitions of pod and capsule, thanks.

"Pod" is KSP lingo. The space industry uses the term capsule.

Edited by Nibb31
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3 minutes ago, Nibb31 said:

Not really. The EFT-1 Orion was pretty much a boilerplate capsule on an interim launcher, with interim avionics, no ECLSS, and no SM. It really only tested reentry and splashdown.

Stuff like how the airframe holds up, LES jettison, capsule RCS systems, and parachute deployment in actual flight conditions were tested in addition to the heat shield.

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5 minutes ago, Ultimate Steve said:

Stuff like how the airframe holds up, LES jettison, capsule RCS systems, and parachute deployment in actual flight conditions were tested in addition to the heat shield.

Sure, the LES was also a boilerplate, not sure if the EFT-1 even had RCS, but the avionics that controlled the flight were an interim version. The parachute system has been extensively tested by drop tests.

As I said, any testing is good, but not much of EFT-1 flight data was useful for validating the final Orion design.

Edited by Nibb31
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Just now, Nibb31 said:

Sure, the LES was also a boilerplate, not sure if the EFT-1 even had RCS. The parachute system has been extensively tested by drop tests.

As I said, any testing is good, but not much of EFT-1 flight data was useful for validating the final Orion design.

Not sure about boilerplate LES, but chances are that the separation motors and the interface between the tower and the capsule were similar. I hear your point about the parachutes, but although those tests brought forth great data, they couldn't quite replicate flight conditions (although they came really close).

https://www.nasa.gov/exploration/systems/mpcv/orion_rcs_pod.html

EFT-1 had capsule RCS.

I agree with you on your last point, though. Any testing is good.

There's also the benefit of being able to analyze the capsule after a spaceflight to see what to improve for the actual functioning models.

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14 minutes ago, Nibb31 said:

"Pod" is KSP lingo. The space industry uses the term capsule.

As long as we're on that topic, is "Apoapse" ever used in the industry, or has it just gotten stuck in my head from Scott Manley?

... Still curious about the duct tape...

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2 minutes ago, Cunjo Carl said:

... Still curious about the duct tape...

I'm not sure about modern day, but they probably have several rolls on the ISS just in case. I was able to find evidence of Duct Tape being used in the shuttle era.

Also, there's this:

Apollo 17 rover on the lunar surface

The crew of Apollo 17 used duct tape and maps to make a replacement fender for their lunar rover.

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So they're still using avcoat for the heat shield, but applying it in blocks, instead of one large honeycomb. So it's not really all that different.

From NSF:

Quote

In all, the honeycomb structure containing the Avcoat material is now composed of 180 individual blocks built in stages.

This change allows the heat shield to meet all strength requirements for EM-1 and future missions of Orion as well as shorten the manufacturing timeline by two months and provides some cost savings to the process as well.

 

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7 hours ago, Wjolcz said:

So was the shuttle. 

Hah, hah, dontgetmestarted. ಠ_ಠ

1 hour ago, Cunjo Carl said:

Does Elon send up duct tape :o

Knowing Elon, there will probably be an entire wheel of it, in its own bin clearly marked “DUCK TAPE“ right between the “FOOD” and “NOT FOOD” bins. 

Boeing, however, will have standardized packages stored in sub-bin 34L, bin 19: sector 4, panel 12, complete with use checklist and MSDS and clearly marked in industry-standard ANSI-approved type, “TAPE, DUCT.”

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6 hours ago, Cunjo Carl said:

... This leads to an important question. Do you think they still send up duct tape?

Does Elon send up duct tape :o

I, for one, don't care how advanced and reliable my spaceship is, if I'm going to Mars I had better have a healthy supply of duct tape in the back. It'll be needed.

Edited by cubinator
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On 5/2/2018 at 8:58 PM, Wjolcz said:

To keep the smaller rover busy and make it think its job is important, of course.

It could be either because they want to avoid some sort of contamination (?) and/or to not put more fatigue on the bigger and more important rover. They would probably rather do more science instead of driving back and forth to fetch the tubes.

 

On 5/2/2018 at 8:50 PM, mikegarrison said:

No, that can't be it.

The plan is to send the sampling rover in one mission and the "fetch" rover plus MAV in another mission. But my question is, why a "fetch" rover at all? Why not have the sampling rover bring the stuff back? If they didn't have a fetch rover, then they could have a bigger MAV and carry back more samples.

The reason is... there is no reason.  NASA is a bureaucracy that consists of smart individuals that collectively, do not end up making efficient decisions due to the fact that it is a jobs program.  Zubrin pointed out with the MSR as an example that NASA keeps turning missions into visions.  A delta-iv heavy could easily send a pathfinder size rover and MAV to Mars and get the sample directly to Earth.  Instead, there are now 2 rovers, an ion powered satellite to grab the sample from Mars orbit, and a manned(!!!!!!!!) mission to retrieve the sample, by which it will be at least 2026, and Elon will be happy to lend NASA a couple dozen pounds.  

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There are a few reasons for the retrieveal rover to be seperate from Mars 2020. First they don‘t have to rely on it to still be runnung by the time the sample return mission takes place, second is that it can keep on its own mission after it has left the samples and doesn‘t have to wait in place or abandon interesting sites to rendezvous with the lander. As for returning the samples with orion, Why not? If you have the LOP/G it wouldn‘t even have to be a purpose launched mission. Just wait for the next crew that would come anyway to take the samples down with them. Using a Solar electric spacecraft they also demonstrate the mission profile of the DST, should they come back to it after having focused on the moon.

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7 minutes ago, Canopus said:

I think Eric is reading a little too much into it.

I agree, but it's still funny.

SLS/Orion was also not mentioned, because there is no plausible reality in which it would matter to getting back to the Moon in any sort of timely way for the simple reason that SLS cannot ever have the launch cadence required to move such an effort forward quickly. That's just a fact. On top of that, short of Block 2, it's not going to the lunar surface, and block 2 is about as far away as warp drive right now.

Edited by tater
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51 minutes ago, tater said:

 

So, let’s see... 8 sets of old boosters remaining, first launch likely in 2020, and one launch per year. That means they have 10 years to come up with new boosters, which is plenty of time. I’m sure they'll manage.  :)

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2 hours ago, tater said:

 

 

1 hour ago, tater said:

 

Hehe.

So if Block I is making three flights (EM-1, EM-2, Clipper), we're only going to see five Block IB flights.

Based on the recent delay of Block IB, the lack of support from POTUS, Shelby leaving the committee, and now Bridenstine plain ignoring SLS/Orion, I think the end is near...........

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