Dragon v2 Kremlinology from Helodriver's unveiling pics

[cscott]

The discussion thread is wondering whether the foot pads are made of PICA-X, or whether PICA-X is too fragile to take the load (or both!  maybe PICA-X will crack under load, but the foot pads can be replaced after each landing).

Anyone want to dig out some of helodriver's pictures and speculate?  (Incidentally, I'm pretty sure the circular "hatches" on the underside which are *not* the legs are the dragon attachment points to the trunk.  http://forum.nasaspaceflight.com/index.php?topic=34828.msg1208650#msg1208650 has some good pictures of these.)

[meekGee]

My 2c on the SDs are that the engines might have been taken out before a public viewing.  Or, even that this article never had them attached for flight yet.

My thought when seeing the light was "no engines".

[cscott]

My 2c on the SDs are that the engines might have been taken out before a public viewing.  Or, even that this article never had them attached for flight yet.

My thought when seeing the light was "no engines".

Helodriver confirmed that there were engines up there.

I'm still wondering how much work it is to safe hypergol engines for public viewing after they've been fired.

[Coastal Ron]

Re quick disconnects of the umbilical section, this looks neat:-

http://www.souriau.com/range-presentation/mil-dtl-38999-series-platform/mil-dtl-38999-series-3-derived/8d9/

Thanks for finding that, and you jogged my memory - we did make a similar version of a quick disconnect like they show in the animation.  It required a pull on the outer ring to release embedded bearings captured in a groove around the receptacle.  While this may work for the launch pad where they can do a direct pull, I'm not sure how it would work with a side panel where the panel has to be "popped" away and then exit behind with the trunk.

No doubt they have it figured out, and I've probably exhausted my ability to contribute to this topic.

[jdnz82]

Hey Guys,
Is anyone able to help me out with the circular shape in this pic of HeloDriver
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=34841.0;attach=586345;image

I've seen it on the old dragon heat shield too - just wondering what its purpose is

[ChrisWilson68]

Hey Guys,
Is anyone able to help me out with the circular shape in this pic of HeloDriver
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=34841.0;attach=586345;image

I've seen it on the old dragon heat shield too - just wondering what its purpose is

I believe that's a trunk attachment point.  There should be six of them.

[Lars_J]

Yep. It is possible they reduced it to 3 attachment points for Dragon 2, because I would expect to see more otherwise.

[MP99]

The discussion thread is wondering whether the foot pads are made of PICA-X, or whether PICA-X is too fragile to take the load (or both!  maybe PICA-X will crack under load, but the foot pads can be replaced after each landing).

Since they are part of the heatshield, ISTM they have to be PICA.

Agree they're likely to be an expendable part of the architecture. Unscrew the old feet, and take a new set out of the parts bin as part of recycling for the next launch.

Maybe send the old ones back to the factory for a refurb.

Cheers, Martin

[ChrisWilson68]

The discussion thread is wondering whether the foot pads are made of PICA-X, or whether PICA-X is too fragile to take the load (or both!  maybe PICA-X will crack under load, but the foot pads can be replaced after each landing).

Since they are part of the heatshield, ISTM they have to be PICA.

Agree they're likely to be an expendable part of the architecture. Unscrew the old feet, and take a new set out of the parts bin as part of recycling for the next launch.

Maybe send the old ones back to the factory for a refurb.

Or, if ITAR will allow it, sell them on eBay.  I'm sure a lot of people would like to have a piece of a genuine spacecraft that has flown to space sitting on their desk.

[john smith 19]

Just uploaded a few minutes of video which may help with some of the Kremlinology on the umbilical panel on the outside of the spacecraft among other things.

https://www.youtube.com/watch?v=nsnQyZCrjsM&feature=youtu.be

Thanks for the video. Nice camerwork. Very smooth. I don't think it's as easy as you make it look. 

I note that the door is more like a vertical version of a large passenger aircraft, rather than simple hinges.

Thinking about it I'm sort of surprise that panel on the side of the capsule, not nearer the underside.

So we're looking at not so much an "umbilical" as more a rigid "bridging" section between capsule and 2nd stage of launcher?

Since you were there can you confirm if the capsule is sort of flattened on the crew entry side, or is really symmetrical and that's just an optical illusion?

[Garrett]

Not sure where to put this, but looking at the control panels in Helodriver's photos I just noticed something that bugs me as a physicist:
The "2" in O2 and CO2 are placed as superscripts and not subscripts! Arghh! 
(see attached image)

Also, it's bad practice, in my opinion, to have the O2 and CO2 levels indicated on 0 - 100% scales. A quick search on the web shows that, from a health perspective, O2 should be between 19% and 24% and CO2 should be less than 0.6%. The indicators should be scaled accordingly.

//Science rant end

[john smith 19]

Not sure where to put this, but looking at the control panels in Helodrivers photos I just noticed something that bugs me as a physicist:
The "2" in O2 and CO2 are placed as superscripts and not subscripts! Arghh! 
(see attached image)

Also, it's bad practice, in my opinion, to have the O2 and CO2 levels indicated on 0 - 100% scales. A quick search on the web shows that, from a health perspective, O2 should be between 19% and 24% and CO2 should be less than 0.6%. The indicators should be scaled accordingly.

//Science rant end

Good points. That suggests 1 of 2 things.
1)This was  how it was done for Shuttle and/or Apollo ( the only permanently crewed long duration spacecraft  the US has flown). IOW it's what the astronauts are trained to use and can interpret at a glance.

2) This is a version 0.1 UI. 

As others have noted there are quite a few things on the console that are contrary to the normal design guidelines of either aircraft or spacecraft, which are well (some might say overly  ) documented. Given the intelligence of modern display driving systems you should be able to build a system that delivers easily understandable data at multiple g and high vibration. I think a modern system could  even cope if you were color blind (provided it was properly designed from day 1).    [EDIT and let's not underestimate the possibilities of sound. Warbles, tones, multiple tones and multiple patterns of tones can supply a lot of information (although they're not so good at doing them all at the same time.  ]

In terms of CO2 levels it's a big thing on submarines and submersibles as well. It drives you're inhalation reflex. IIRC at 1% you're panting like you've run miles wearing a weight belt. At 2% I think you're looking at unconsciousness and brain damage.  For the really paranoid it would have a fallback "monochrome" mode in case you lose one or more color channels.

[jdnz82]

Hey Guys,
Is anyone able to help me out with the circular shape in this pic of HeloDriver
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=34841.0;attach=586345;image

I've seen it on the old dragon heat shield too - just wondering what its purpose is

I believe that's a trunk attachment point.  There should be six of them.

Ah cool thanks guys! Much appreciated!!

[Kabloona]

Helodriver confirmed that there were engines up there.

[/quote]

As several other people have pointed out, that seems quite unlikely since there are circles of light in the video where the SD thrust chambers should be. I doubt there is even any propulsion plumbing installed. It's hardly more than a structural shell at this point, which is common for "unveilings" of this kind.

I didn't see Helodriver's comment, but is it possible that he meant an SD was "up there" on stage? Because there clearly is no SD "up there" in the nacelles.

Edit: however, it does look like the Dracos nozzles have been "potted" into place, so perhaps Helodriver was confirming that the Dracos were installed.

[woods170]

Helodriver confirmed that there were engines up there.

As several other people have pointed out, that seems quite unlikely since there are circles of light in the video where the SD thrust chambers should be. I doubt there is even any propulsion plumbing installed. It's hardly more than a structural shell at this point, which is common for "unveilings" of this kind.

I didn't see Helodriver's comment, but is it possible that he meant an SD was "up there" on stage? Because there clearly is no SD "up there" in the nacelles.

You make a bold statement for someone who was not actually present at the event.

[Llian Rhydderch]

Hey Guys,
Is anyone able to help me out with the circular shape in this pic of HeloDriver
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=34841.0;attach=586345;image

I've seen it on the old dragon heat shield too - just wondering what its purpose is

I believe that's a trunk attachment point.  There should be six of them.

Question re the dynamics of this, to someone who might be able to offer an engineering view on it:

Might a trunk attachment design be modified a bit for Dragon V2 where only three points (vs 6 in DV1) are the traditional SpaceX design (with the load member taking both tension and compression) while the remainder of the compressive loads during launch acceleration might be applied through a stiff load bearing point in the center of each of the four (retracted) landing legs?

In other words, with the four new breaks in the TPS for the four landing legs, might not they be able to transfer some substantial portion of the compressive acceleration loads to the capsule, while having a reduced number of the legacy attachment points that would handle both tension and compression, and it would be only three points that "hold the capsule and the trunk together."

[Kabloona]

Helodriver confirmed that there were engines up there.

As several other people have pointed out, that seems quite unlikely since there are circles of light in the video where the SD thrust chambers should be. I doubt there is even any propulsion plumbing installed. It's hardly more than a structural shell at this point, which is common for "unveilings" of this kind.

I didn't see Helodriver's comment, but is it possible that he meant an SD was "up there" on stage? Because there clearly is no SD "up there" in the nacelles.

You make a bold statement for someone who was not actually present at the event.

Just asking the question, if the SD's are installed, why are there circles of light where dark thrust chambers should be? So far no one seems to have a good answer.

[oiorionsbelt]

Question re the dynamics of this, to someone who might be able to offer an engineering view on it:

Might a trunk attachment design be modified a bit for Dragon V2 where only three points (vs 6 in DV1) are the traditional SpaceX design (with the load member taking both tension and compression) while the remainder of the compressive loads during launch acceleration might be applied through a stiff load bearing point in the center of each of the four (retracted) landing legs?

In other words, with the four new breaks in the TPS for the four landing legs, might not they be able to transfer some substantial portion of the compressive acceleration loads to the capsule, while having a reduced number of the legacy attachment points that would handle both tension and compression, and it would be only three points that "hold the capsule and the trunk together."

This is my thinking on this as well.   Not only could the legs take the loads the way the old attachments points did but the feet would be made from the same material as the old attachment points.

[Herb Schaltegger]

Just asking the question, if the SD's are installed, why are there circles of light where dark thrust chambers should be? So far no one seems to have a good answer.

He posted (in this thread or one of the others) that the nozzle linings are reflective and he had a light source on his camera.

[cscott]

Helodriver confirmed that there were engines up there.

As several other people have pointed out, that seems quite unlikely since there are circles of light in the video where the SD thrust chambers should be.

Helodriver explicitly stated that the floor was brightly lit, and the white circles were the reflection of the brightly lit white floor from the shiny metal interior of the draco:

The inside of the engine bells was silver metal, lit by the white light coming up from the illuminated platform floor below.

It's actually pretty cool how the human eye can resolve ambiguities like this.  See http://web.mit.edu/persci/people/adelson/pub_pdfs/adelson_spie_01.pdf for how we can infer shape from reflectivity and  http://qz.com/192874/is-the-oculus-rift-designed-to-be-sexist/ for a discussion of “motion parallax” and “shape-from-shading.”  Cameras really don't capture the full range of what the eye can see (and how we can move our head to help 'see' it).