Author Topic: LIVE: SpaceX Falcon 9/Dragon CRS-2 (SpX-2) LAUNCH and FD-1 UPDATES (Read 278931 times)

Robotbeat · « **Reply #220 on:** 03/01/2013 03:13 pm »

Quote from: Jason1701 on 03/01/2013 03:11 pm

Quote from: Space Pete on 03/01/2013 03:09 pm
Per Elon's latest Tweet, I'm assuming removing the inhibits didn't work?

Or it could take a while to implement.

Indeed, since they're in orbit now, they can take their time to make sure they don't make anything worse.

Quote from: dedead on 03/01/2013 03:12 pm

Quote from: riney on 03/01/2013 03:10 pm
It's important to note that, aside from sitting on the ground, being on orbit is the safest place for something to go wrong. Plenty of time to analyze data and work the problem.
Depends of batterie remaining time !

~18 hours of battery life.

Targeteer · « **Reply #221 on:** 03/01/2013 03:13 pm »

elonmusk About to pass over Australia ground station and command inhibit override

corrodedNut · « **Reply #222 on:** 03/01/2013 03:14 pm »

Orbital mechanics question: How does delayed (knock on wood) firings affect rendvz?

padrat · « **Reply #223 on:** 03/01/2013 03:14 pm »

Being my first launch I don't really know enough about what's going on to say anything and I prob couldn't even if I did. Sorry guys. Ill just say they are working the problem and making progress. Cross your fingers....

Jason1701 · « **Reply #224 on:** 03/01/2013 03:14 pm »

Quote from: corrodedNut on 03/01/2013 03:14 pm

Orbital mechanics question: How does delayed (knock on wood) firings affect rendvz?

If they miss their first firing, which IIRC was ~2.5 hours after launch, the rendezvous would probably take a lot longer.

avollhar · « **Reply #225 on:** 03/01/2013 03:15 pm »

Quote from: Jason1701 on 03/01/2013 03:11 pm

Quote from: Space Pete on 03/01/2013 03:09 pm
Per Elon's latest Tweet, I'm assuming removing the inhibits didn't work?

Or it could take a while to implement.

First you want to make sure why the computer inhibited the pods before overriding it. It sure happened for a reason.. They have 18h of battery life according to another post to check and verify before pulling out the stops manually.

Update: Tweet from Elon.."About to pass over Australia ground station and command inhibit override"

Robotbeat · « **Reply #226 on:** 03/01/2013 03:15 pm »

Quote from: hektor on 03/01/2013 03:12 pm

Well we could have a very big space debris overhead in 18 hours. If no deorbit, how long will it take for Dragon to decay ?

Nowhere near that sort of conclusion, yet. Inhibit on the thrusters sounds just like a problem that can be fixed remotely and they have comms.

Dragon is a very complicated spacecraft with lots of redundancies... This complexity and multiple overlapping safety systems likely contributed to this issue in the first place, but it also means they'll probably be able to resolve it and complete the mission successfully.

Antares · « **Reply #227 on:** 03/01/2013 03:15 pm »

I thought that tipoff angle looked pretty heinous. Dragon should have nulled it faster than that.

Note that one Elon tweet was deleted.

Just to state the obvious that doesn't seem to have been stated, Dragon needs Dracos for entry control, let alone deorbit impulse.

Joel · « **Reply #228 on:** 03/01/2013 03:16 pm »

Can someone explain what "inhibit" means in this context? Is it something physical?

Jason1701 · « **Reply #229 on:** 03/01/2013 03:17 pm »

Quote from: Antares on 03/01/2013 03:15 pm

Note that one Elon tweet was deleted.

What did it say?

Joel: it's referring to a software command in Dragon's flight computers.

Orbiter · « **Reply #230 on:** 03/01/2013 03:17 pm »

Quote from: Antares on 03/01/2013 03:15 pm

I thought that tipoff angle looked pretty heinous. Dragon should have nulled it faster than that.

Note that one Elon tweet was deleted.

Just to state the obvious that doesn't seem to have been stated, Dragon needs Dracos for entry control, let alone deorbit impulse.

None of Elon's tweets have been deleted for me.

yg1968 · « **Reply #231 on:** 03/01/2013 03:17 pm »

Elon Musk Tweet:

Quote from: Elon Musk

About to pass over Australia ground station and command inhibit override

krytek · « **Reply #232 on:** 03/01/2013 03:18 pm »

Inhibit means computer won't allow it

edkyle99 · « **Reply #233 on:** 03/01/2013 03:19 pm »

Quote from: Antares on 03/01/2013 03:15 pm

I thought that tipoff angle looked pretty heinous. Dragon should have nulled it faster than that.

Note that one Elon tweet was deleted.

Just to state the obvious that doesn't seem to have been stated, Dragon needs Dracos for entry control, let alone deorbit impulse.

I'm trying to picture if Dragon can be prevented from tumbling out of control on only one set of thrusters. Tumble might cause command troubles, etc. A race against time, though there is time.

- Ed Kyle

Nickolai · « **Reply #234 on:** 03/01/2013 03:20 pm »

Quote from: Jason1701 on 03/01/2013 03:14 pm

Quote from: corrodedNut on 03/01/2013 03:14 pm
Orbital mechanics question: How does delayed (knock on wood) firings affect rendvz?

If they miss their first firing, which IIRC was ~2.5 hours after launch, the rendezvous would probably take a lot longer.

I feel like they'll resolve the issue, they've got to have overrides for this sort of thing, but if they don't and they miss the firings, at what point does it become LOM because Dragon has fallen far enough behind the ISS that there won't be enough prop to catch up? (a bit of a crude orbital mechanics explanation but hopefully people get the gist)

Robotbeat · « **Reply #235 on:** 03/01/2013 03:20 pm »

Quote from: Jason1701 on 03/01/2013 03:14 pm

Quote from: corrodedNut on 03/01/2013 03:14 pm
Orbital mechanics question: How does delayed (knock on wood) firings affect rendvz?

If they miss their first firing, which IIRC was ~2.5 hours after launch, the rendezvous would probably take a lot longer.

Informative!

Quote from: Antares on 03/01/2013 03:15 pm

I thought that tipoff angle looked pretty heinous. Dragon should have nulled it faster than that.

Note that one Elon tweet was deleted.

Just to state the obvious that doesn't seem to have been stated, Dragon needs Dracos for entry control, let alone deorbit impulse.

If they can command jettison of the trunk, perhaps they may be able to put the spacecraft in a stable position for ballistic reentry? They have at least one good thruster pod (enough for rough attitude control) and a good chance all the pods are good (have to find out why the thrusters are inhibited... I didn't see any major venting, so I doubt half their propulsion system destroyed itself or something like that).

Garrett · « **Reply #236 on:** 03/01/2013 03:22 pm »

Quote from: yg1968 on 03/01/2013 03:17 pm

Elon Musk Tweet:

Quote from: Elon Musk
About to pass over Australia ground station and command inhibit override

No Heavens Above tracking of Dragon, so this will have to do. I presume Dragon is trailing by less than half an orbit?

Chris Bergin · « **Reply #237 on:** 03/01/2013 03:23 pm »

SpaceX PAO:
One thruster pod is running. Two are preferred to take the next step which is to deploy the solar arrays. We are working to bring up the other two in order to plan the next series of burns to get to station.

Jason1701 · « **Reply #238 on:** 03/01/2013 03:24 pm »

Quote from: Chris Bergin on 03/01/2013 03:23 pm

SpaceX PAO:
One thruster pod is running. Two are preferred to take the next step which is to deploy the solar arrays. We are working to bring up the other two in order to plan the next series of burns to get to station.

"The other two?" Elon said there were four total..

Also, even if "two are preferred," they might still decide to deploy the arrays on one pod if they need more than the 18 hours of battery life.

cro-magnon gramps · « **Reply #239 on:** 03/01/2013 03:25 pm »

can they un-inhibit individual pods? thinking if they can, it might give them further info to correct the others...