SpaceX Falcon 9 v1.1 - SES-8 - DISCUSSION THREAD

[WHAP]

Need a link to a replay of the retract..  anyone?

Sure, but why are you asking, rather than just posting it or a link to it?

I'm asking too.  Where does one find a replay of the retract?  I did not record it myself, and don't find it on youtube.  You know we're all going to speculate here - might be beneficial to see if the retraction did pull the umbilicals.  I wasn't able to tell for sure from the Cassiope video, but it did not appear that any umbilicals actually disconnected when the strongback pulled back.

[Avron]

Need a link to a replay of the retract..  anyone?

Sure, but why are you asking, rather than just posting it or a link to it?

I would like to compare this retract to the last one .  If you have a link to a video of the final abort count today, that would be welcome

[Kabloona]

Was the vent really the cause for the scrub? My impression (could be wrong!) was that seemed to be related to the early disconnection of the fairing umbilicals.

SFN quoting Insprucker as saying abort was caused by off-nominal condition in S1 LOX pressurization system.

Edit: apparently just confirmed by Elon tweet.

[411rocket]

I'm asking too.  Where does one find a replay of the retract?  I did not record it myself, and don't find it on youtube.  You know we're all going to speculate here - might be beneficial to see if the retraction did pull the umbilicals.  I wasn't able to tell for sure from the Cassiope video, but it did not appear that any umbilicals actually disconnected when the strongback pulled back.

The retraction did pull the payload umbilicals today, saw it over the video feed. The loop did not open up to span the gap, from the increased distance. I don't remember that happening last launch.

[Lars_J]

Was the vent really the cause for the scrub? My impression (could be wrong!) was that seemed to be related to the early disconnection of the fairing umbilicals.

SFN quoting Insprucker as saying abort was caused by off-nominal condition in S1 LOX pressurization system.

Edit: apparently just confirmed by Elon tweet.

Ok, thanks!

[deltaV]

Do we have confirmation that there was an anomaly with the transporter/erector that stopped it from returning to grab the rocket after the abort? Any details as to what's wrong and how long it will take to fix it?

[DrLucky]

I'm asking too.  Where does one find a replay of the retract?  I did not record it myself, and don't find it on youtube.  You know we're all going to speculate here - might be beneficial to see if the retraction did pull the umbilicals.  I wasn't able to tell for sure from the Cassiope video, but it did not appear that any umbilicals actually disconnected when the strongback pulled back.

The retraction did pull the payload umbilicals today, saw it over the video feed. The loop did not open up to span the gap, from the increased distance. I don't remember that happening last launch.

I, too, went back to review the Sept launch.  But it occurred to me that different spacecraft may have different procedures.  I'm not sure if it's normal for the LV provider to always do things the same way, or if something like that would differ from payload to payload.

Given what Elon has said, it would seem that it wasn't the deciding issue, at any rate.

Be interesting to see what happens to the umbilical the next time the strongback retracts on this spacecraft, since that's the only data point we'll have with complete commonality.  Really not enough data to guess about an anomaly since we really only have one good data point.

[Jim]

Payload umbilicals don't disconnect until after lift off.  There needs to be the ability to command and monitor the spacecraft or provide power up to T-0.
We don't even know if that particular umbilical is for the payload.

[Kabloona]

Do we have confirmation that there was an anomaly with the transporter/erector that stopped it from returning to grab the rocket after the abort? Any details as to what's wrong and how long it will take to fix it?

Here:


Just after the "hold" call, at about 1:14 into the video, someone can be heard saying "the...stage one LOX ullage was...", possibly stating the reason for the hold, which we now know was related to stage one LOX ullage pressure. Unfortunately, we don't hear the rest of his sentence.

At 7:00  the LC refers to a "strongback raise anomaly."

[WHAP]

I didn't see any more umbilicals connected to the payload fairing.  Sure makes me wonder about how the spacecraft will fare in that humid environment.   Not clear if there's a separate power umbilical or if that comes from a lower one, but the one that disconnected sure looked like HVAC.

[Jim]

That is the first I saw of the retract.  That would be the fairing ac umbilical and not an electrical umbilical.  Big no no.  Spacecraft has to be a little concerned.

Power and comm to the spacecraft come up through the second stage via the payload adaptor and hence lower umbilicals

[Prober]

I'm asking too.  Where does one find a replay of the retract?  I did not record it myself, and don't find it on youtube.  You know we're all going to speculate here - might be beneficial to see if the retraction did pull the umbilicals.  I wasn't able to tell for sure from the Cassiope video, but it did not appear that any umbilicals actually disconnected when the strongback pulled back.

The retraction did pull the payload umbilicals today, saw it over the video feed. The loop did not open up to span the gap, from the increased distance. I don't remember that happening last launch.

I, too, went back to review the Sept launch.  But it occurred to me that different spacecraft may have different procedures.  I'm not sure if it's normal for the LV provider to always do things the same way, or if something like that would differ from payload to payload.

Given what Elon has said, it would seem that it wasn't the deciding issue, at any rate.

Be interesting to see what happens to the umbilical the next time the strongback retracts on this spacecraft, since that's the only data point we'll have with complete commonality.  Really not enough data to guess about an anomaly since we really only have one good data point.

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

[Avron]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

[Rocket Science]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

I saw that as well, a massive vent with the coinciding with the call... Then sheets of ice came off the vehicle...

[Avron]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

I saw that as well, a massive vent with the coinciding with the call...

Just depressing the tanks.. something that tells me that they have aborted... remember the tanks get pressurized for launch..

[Rocket Science]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

I saw that as well, a massive vent with the coinciding with the call...

Just depressing the tanks.. something that tells me that they have aborted... remember the tanks get pressurized for launch..

Yes, and perhaps over pressurized?

[mlindner]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

I saw that as well, a massive vent with the coinciding with the call...

Just depressing the tanks.. something that tells me that they have aborted... remember the tanks get pressurized for launch..

Yes, and perhaps over pressurized?

Why would you think over pressurized? I doubt it.

[mlindner]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

I saw that as well, a massive vent with the coinciding with the call... Then sheets of ice came off the vehicle...

Sheets of ice came off the vehicle way before that.

[DaveS]

My impression for what its worth....Every SpaceX launch from that pad in one way or another has had Lox issues.
This launch was like a completely different from the Vandenberg launch.  In that launch the sb moved back and the noticeable pressure of the connections.   Did the SB retract all the way in this launch, or have the procedures changed?
 

I was looking at that.. looks like it stops at the venting associated with the abort .. cannot be sure

I saw that as well, a massive vent with the coinciding with the call...

Just depressing the tanks.. something that tells me that they have aborted... remember the tanks get pressurized for launch..

Yes, and perhaps over pressurized?

Negative. Flight pressure is significantly higher than the standard pre-launch post-tanking pressure. So what you saw was the immediate release of that delta pressure (delta-p) when the automatic sequencer cut-off the count and commanded the stage 1 vent valve to full open. This rapid change in pressure caused the stage to vibrate enough to dislodge some of the ice that had formed on the exterior of the stage 1 LOX tank.

It was nothing anomalous, it was exactly how the system should work as the last thing you'd want in a case like this is a potential unstable bomb just waiting to detonate. By fully opening the vent valve you remove that extra pressure inside the tank that is no longer necessary.
Remember, LOX is a cryogenic liquid that keeps boiling off and turning into GOX. This GOX increases the pressure inside the tank so it needs somewhere to go unless you want the tank to overpressurize and explode. This is handled by a pressure relief valve at the top of the tank. The excess GOX is vented overboard and there's no risk of overpressure unless the relief valve fails in the closed position.

[guckyfan]

Why is the next launch window only on thursday? I thought there would be a window to GTO daily. Or is it time they need to ready the launch vehicle again?

Thanks.