SpaceX COTS Demo 2/3 Updates (THREAD 2)

[Robotbeat]

Maybe combing Demo 2/3 was a bad idea?    Had Demo 2 launched by now these problem might have been fixed?   The focus on saving costs, and time, sometimes bites you and you find out in the end you didn’t save anything.

Probably not. COTS 2 alone would be station prox ops, so I'm guessing a lot of these issues would need to be fixed anyway. ...

Have to agree with that.

[Lurker Steve]

Maybe combing Demo 2/3 was a bad idea?    Had Demo 2 launched by now these problem might have been fixed?   The focus on saving costs, and time, sometimes bites you and you find out in the end you didn’t save anything.

Probably not. COTS 2 alone would be station prox ops, so I'm guessing a lot of these issues would need to be fixed anyway. Otherwise, why not just remanifest as COTS 2 only and launch on Feb 7? Clearly they are not doing that.

Combining Orbcomm was a bad idea, and since been undone.

I thought the OrbComm secondaries caused unnecessary delays, due to the extra approval process that they had to go through. It seems that the flight software wasn't really cooked yet anyway, so in the end, there is no way they could have flown last fall.

[MikeMelga]

Most of the work should be able to happen in parallel. The guys working on EMI aren't depending on trajectory refinements to do their tasks and vice versus, for example.

About the EMI problem, I have my questions if they can solve this at the Cape. Do they have the shielded environment to do the testings or they need to transfer dragon back to their main facility?

If it is a very isolated problem, they can just replace a circuit. But usually EMI tests are done for the whole vehicle.
I have a friend that worked on an all-electric bus and they had to do an EMI test where the whole bus would be rotated! This was done on a special hangar on Germany.

Also EMI failure might be in the acceptance of external interference, not emission. Or even static discharge, for example when it touches the ISS.

[Comga]

On page 17 of the Jan 16 issue of Aviation Week, an article by Jen Dimascio says
"..and final approval for Dragon to approach the station will not come until at least three dys after launch."  This conflicts with some posted schedules, which have the berthing two days after launch.

It also say "By then, it should be clear whether SpaceX has control over the 20-ton vehicle as it orbits."
20 tons?  That's high, isn't it?

[Robotbeat]

On page 17 of the Jan 16 issue of Aviation Week, an article by Jen Dimascio says
"..and final approval for Dragon to approach the station will not come until at least three dys after launch."  This conflicts with some posted schedules, which have the berthing two days after launch.

It also say "By then, it should be clear whether SpaceX has control over the 20-ton vehicle as it orbits."
20 tons?  That's high, isn't it?

Apparently, Dragon has had considerable mass growth. And Falcon 9 just got a lot more capable!

[kch]

On page 17 of the Jan 16 issue of Aviation Week, an article by Jen Dimascio says
"..and final approval for Dragon to approach the station will not come until at least three dys after launch."  This conflicts with some posted schedules, which have the berthing two days after launch.

It also say "By then, it should be clear whether SpaceX has control over the 20-ton vehicle as it orbits."
20 tons?  That's high, isn't it?

That's the stretch-limo version -- seats 18 ...

[Patchouli]

On page 17 of the Jan 16 issue of Aviation Week, an article by Jen Dimascio says
"..and final approval for Dragon to approach the station will not come until at least three dys after launch."  This conflicts with some posted schedules, which have the berthing two days after launch.

It also say "By then, it should be clear whether SpaceX has control over the 20-ton vehicle as it orbits."
20 tons?  That's high, isn't it?

I think someone just confused it with Orion or ATV.


Though on the EMI I think they have a Lidar,telemetry down link,video down link,command up link, etc and these all have to play nice with each other.
Not sure if there also is a radar or not but other vehicles operating around ISS have one.

[RocketmanUS]

On page 17 of the Jan 16 issue of Aviation Week, an article by Jen Dimascio says
"..and final approval for Dragon to approach the station will not come until at least three dys after launch."  This conflicts with some posted schedules, which have the berthing two days after launch.

It also say "By then, it should be clear whether SpaceX has control over the 20-ton vehicle as it orbits."
20 tons?  That's high, isn't it?

More like 20,000lb , Dragon plus cargo and fuel.

[RocketJack]

Maybe combing Demo 2/3 was a bad idea?    Had Demo 2 launched by now these problem might have been fixed?   The focus on saving costs, and time, sometimes bites you and you find out in the end you didn’t save anything.

Yeah, maybe. Would love to hear other perspectives on this?

Well, remember that they are only combined in the sense that if the COTS 2 objectives are met, NASA has said that they can proceed with COTS 3 objectives(prox ops and berthing). That makes sense because if you have a perfect COTS 2 demo with a perfectly well behaving spacecraft, why wouldn't you continue on? The real key to deciding whether to combine COTS 2 and 3 was whether SpaceX was willing to take the risk of setting expectations that are not met. This is a  real issue; unless they complete COTS 2 objectives, press in and berth, the flight will generally be seen as a failure. Risk v. Reward. This is also the root of why Orbcomm was kicked off - prop margins were too tight and could have endangered the completion of COTS 2/3 objectives, especially given performance issues with a full Dragon.

[dcporter]

I believe that you don't need a final cots-3 dragon to perform cots-2. The question is whether they could have had a cots-2 dragon ready significantly sooner than it's taken them to do the full-up cots-2/3.

[marsman2020]

I believe that you don't need a final cots-3 dragon to perform cots-2. The question is whether they could have had a cots-2 dragon ready significantly sooner than it's taken them to do the full-up cots-2/3.

The payments that SpaceX gets from NASA under COTS are based on meeting milestones.   It's not a cost-plus contract.  Getting NASA to agree to (potentially) combine the milestones into one flight means SpaceX gets paid the same amount for all the milestones, but they only have to build and fly 1 Falcon 9 and 1 Dragon instead of 2 Falcon 9s and 2 Dragons.  Also, the taxpayers only get data on the flight of 1 F9 and 1 Dragon before moving into the CRS contract, vs 2 F9s and 2 Dragons.

Since they haven't launched a commercial customer payload since F1-5 in 2009, the only income is from COST/CRS milestones, investors, and taking deposits from customers on Launch B, C, and D and using the money to pay for Launch A in what is basically a space industry ponzi scheme. 

It doesn't matter if they could have flown COTS2 on its own sooner, it's all about the $$$.  Taking 6 months longer is nothing compared to building an entire 2nd vehicle. 

Orbcomm must be getting mighty annoyed.  Their future business depends on those satellites getting launched. 

[Lars_J]

Since they haven't launched a commercial customer payload since F1-5 in 2009, the only income is from COST/CRS milestones, investors, and taking deposits from customers on Launch B, C, and D and using the money to pay for Launch A in what is basically a space industry ponzi scheme.

Technically, the small sats launched on the last F9 flight were commercial - even if they did not get paid much for them.

[Norm38]

About the EMI problem, I have my questions if they can solve this at the Cape. Do they have the shielded environment to do the testings or they need to transfer dragon back to their main facility?

Depends on if the problem is conducted or radiated.  Conducted EMI test equipment is fairly portable and testing can be done just about anywhere, just plug into the power system because the noise is in the wires.
Radiated test equipment is about the same size, not including the antenna.  But if Radiated testing is done in open air, you'll pick up every single transmitter on the air.  The old analog TV signals were narrow enough, one could usually see the noise floor rise on either side of the carrier, and know there was an issue there.  But with the new broadband digital TV broadcasts, good luck figuring out if the system radiates at the same frequency.  Shielded rooms are becomming essential for Radiated EMI work.

As for fiber optics, a transmission's range is based on power and digital signals are quite weak.  In all my radio experience, it's the power lines not the signal lines that cause most EMI issues.  And optical can't transmit power.

[docmordrid]

>
And optical can't transmit power.

JDSU's Photonic Power can transmit up to 1 watt @2-12v. Efficiency: 35-39%. Scalable? Dunno.

http://www.jdsu.com/en-us/photovoltaics/products/photonic-power/pages/default.aspx

[Space Pete]

There may now be a possible schedule conflict between the delayed Soyuz TMA-04M launch and TMA-22 return.

http://forum.nasaspaceflight.com/index.php?topic=27678.msg855061#msg855061

AFP: Russia 'to postpone next manned space launch'
http://www.google.com/hostednews/afp/article/ALeqM5hHonNkSx76_s6cJApIH4XheVHeSA

[woods170]

There may now be a possible schedule conflict between the delayed Soyuz TMA-04M launch and TMA-22 return.

http://forum.nasaspaceflight.com/index.php?topic=27678.msg855061#msg855061

AFP: Russia 'to postpone next manned space launch'
http://www.google.com/hostednews/afp/article/ALeqM5hHonNkSx76_s6cJApIH4XheVHeSA

Doesn't that post belong in the ISS thread? Or Russian launchers thread?

[Space Pete]

Doesn't that post belong in the ISS thread? Or Russian launchers thread?

No, I only posted it here since it may have an effect on the C2/C3 mission. Full coverage of course belongs on the Russian thread.

[cuddihy]

Doesn't that post belong in the ISS thread? Or Russian launchers thread?

No, I only posted it here since it may have an effect on the C2/C3 mission. Full coverage of course belongs on the Russian thread.

So the delay to COTS 2/3 would be due to return of sufficient Dragon-trained crew to conduct rendezvous? or am I misunderstanding?

[Space Pete]

So the delay to COTS 2/3 would be due to return of sufficient Dragon-trained crew to conduct rendezvous? or am I misunderstanding?

It could be that, or it could be that the Dragon flight events would occur on the same date as Soyuz launches/dockings/undockings (I doubt Dragon would be allowed to conduct prox ops with ISS while a Soyuz was en route).

[docmordrid]

The March 30 Soyuz flight may have to be delayed due to an air leak -

Link....