SpaceX Falcon 9/Dragon CRS SpX-1 MISSION GENERAL DISCUSSION

[Space Pete]

One thing to keep an eye on is the two SIGIs (Space Integrated GPS/INS), since both of those being operational is a LCC (Launch Commit Criteria) for a Dragon launch, and one of the SIGIs failed close to the previous Dragon launch. Dragon uses the SIGIs for RGPS (Relative GPS) navigation with the ISS.

You can keep track of the two SIGI's status on ISSLive! here, where they are noted as GPS-1 and GPS-2. Their nominal state is "DOING POSIT".
http://spacestationlive.jsc.nasa.gov/displays/adcoDisplay4.html

Just an update, but the SIGIs look like they're holding up!

So that's in violation of the old engineering rule "If anything can go wrong, it will do so at the most inopportune time".

[Space Pete]

L-6 hours, so the most inopportune times are still ahead.

After the scrub, we can look back at this post as the moment Pete jinxed it.

*Disclaimer: Pete reserves the right not to be held liable for any Dragon launch scrubs due to SIGI failure(s).

[Space Pete]

L-6 hours, so the most inopportune times are still ahead.

L-1h 15m, and they're still going strong.

Come on, little SIGIs!

[simonbp]

Down to 20% unfavorable!

[Space Man Spiff]

Is this an instantaneous launch window, or could they recycle?

[Chris Bergin]

Is this an instantaneous launch window, or could they recycle?

Instant.

[Jason1701]

Is this an instantaneous launch window, or could they recycle?

It's short enough that they can't recycle in time after a hold, so effectively instantaneous.

[krytek]

Any idea whose the dragon catcher this time?
*edit* Never mind, they just answered it. It's Sunita Williams and Akihiko Hoshide.

[Space Pete]

L-6 hours, so the most inopportune times are still ahead.

After the scrub, we can look back at this post as the moment Pete jinxed it.

Well, those SIGIs held up! They must have got the good vibes I sent them.

[AS-503]

Why did the second stage roll control thruster only fire (repeatedly) in one direction?

Normally you see it burn aprox. equally amount of times (about 45 degrees left/right).

Any thoughts?
 

[QuantumG]

Why did the roll control thruster only fire (repeatedly) in one direction?

Normally you see it burn aprox. equally amount of times (about 45 degrees left/right).

Any thoughts?

Gwynne said in the preflight press conference that they're going to a different orbit this time.

[krytek]

Anyone knows why Falcon's engines shine in the form of a six pointed star?

[Robotbeat]

Anyone knows why Falcon's engines shine in the form of a six pointed star?

That is an artifact from the camera (diffraction about a hexagonal aperture).

[JBF]

do we have a timeline for the orbcomm deployment?

[QuantumG]

do we have a timeline for the orbcomm deployment?

I've not seen anything reliable about it at all.

[Robotbeat]

do we have a timeline for the orbcomm deployment?

I've not seen anything reliable about it at all.

It is supposed to happen at 937pm et, so in about 15 minutes.

[krytek]

Anyone knows why Falcon's engines shine in the form of a six pointed star?

That is an artifact from the camera (diffraction about a hexagonal aperture).

i.e lens flare. Thank you. 

[Robotbeat]

Anyone knows why Falcon's engines shine in the form of a six pointed star?

That is an artifact from the camera (diffraction about a hexagonal aperture).

i.e lens flare. Thank you. 

Not caused by lenses, really. caused by the shape of the aperture iris.

[corrodedNut]

"Corner"? Something seems to disintegrate right at +1:20. MaxQ, "vehicle is supersonic" then poof. Looks too rough to be a shock ring type effect.

[StephenB]

Wow. Fortunately the first stage seems to have been robust enough.