SpaceX Falcon 9 : TESS : April 18, 2018 : Discussion

[Jarnis]

After today's flight and the Bangabandhu in May, 90% will have soot. 

...and Bangabandhu won't be all white. This is the last all-white one unless they decide to repaint a Block 4 for re-flight.

[Tea Party Space Czar]

Small video all about TESS



This is the best mission for me personally, since Kepler.

[zubenelgenubi]

Cross-post re: TESS

TESS's daily launch times.

Why the 45-day gap for InSight's launch (April 27 through June 9)?

[rockets4life97]

Why the 45-day gap for InSight's launch (April 27 through June 9)?

It would only be a 45-day standout if InSight launches on the last possible day (or is scrubbed on the last possible day). Insight is another NASA launch that uses the same NASA team, so they can't work both launches at the same time. Insight has priority given its smaller launch window.

[cppetrie]

What is the reason for the scrub?

The answer is literally four posts above yours in #76. Plus that is the updates thread.

[spacenut]

So I am to assume there is nothing wrong with the rocket or the TESS satellite, just critical launch timing? 

You Tube said they were doing additional tests on the launch controls and guidance systems. 

[Jim]

For TESS, 30 second launch window is for COLA (Collision Avoidance).  Should a COLA be needed, they can shift the launch time by as much as 30 seconds to the right.

Collision with what? Uncharted space debris? How would it be detected and relayed to the launch team?

The final analysis is done around 24 hours before launch and they can adjust the T-0

[cppetrie]

So I am to assume there is nothing wrong with the rocket or the TESS satellite, just critical launch timing? 

You Tube said they were doing additional tests on the launch controls and guidance systems.

There has been no indication so far of a problem with the rocket or satellite.

[OnWithTheShow]

Do you think these additional GNC tests are due to the unique orbit of TESS? As far as we know F9 has a perfect GNC record with a pretty predictable final orbit variance right?

[mulp]

Wonder what goes through Elon's mind when launches are delayed for "minor" issues that will cause mostly reputational costs compared to about a decade ago when a delay meant running out of cash to do anything at all (2008-09-28), costing the future of SpaceX.

But his experience being the decider for the first four SpaceX launches might have cured him of risk taking by pushing others to ignore even minor issues.

[Herb Schaltegger]

Wonder what goes through Elon's mind when launches are delayed for "minor" issues that will cause mostly reputational costs compared to about a decade ago when a delay meant running out of cash to do anything at all (2008-09-28), costing the future of SpaceX.

Well, per his Twitter feed, he spent a lot of this afternoon driving a Model 3 and listening to hip-hop.

(In other words, he's not nearly as worried as he would've been 8 or 10 years ago).

[TorenAltair]

No landing bingo this time? Avoiding bad omen as all last bingos failed? 

[Wolfram66]

Hawk is showing up on MarineTraffic.Com showing expected location of landing zone
Hawk, Go Go's ships and OCISLY hanging out waiting to play catch

thanks to MarineTraffic.com

[shooter6947]

Hawk is showing up on MarineTraffic.Com showing expected location of landing zone
Hawk, Go Go's ships and OCISLY hanging out waiting to play catch

Looks pretty close-in -- lofted trajectory?

[the_other_Doug]

Hawk is showing up on MarineTraffic.Com showing expected location of landing zone
Hawk, Go Go's ships and OCISLY hanging out waiting to play catch

Looks pretty close-in -- lofted trajectory?

I imagine it's a combination of a (comparatively) very light payload and a very high-apogee target orbit.  My take is that the overall staging conditions required fall *just* short of giving the booster enough energy for an RTLS.

If this was a significantly more massive payload, or the target orbit was at higher energy than it is, the droneship would likely be stationed farther downrange.

I don't believe it is necessarily an indication of a lofted trajectory.  Just that the stage will have *almost* enough energy left at MECO to get back to the launch site.  Almost.

[mn]

Our exact launch window today is 18:51:31 - 18:52:01 EDT (22:51:31 - 22:52:01 UTC)

Now we know that with the F9 they can't really hold the count, so once they start the LOX load, they are committed to a specific launch time.

But I'm going to go out on a limb here and guess they can hold for 30 seconds if needed up to some point even after LOX loading?

So does anyone have any specific info on this?

(As asked earlier the 30 second window was related to some kind of collision avoidance, but never got a clear explanation of what they are avoiding and at what point in time do they need to make this adjustment).

[shooter6947]

Hawk is showing up on MarineTraffic.Com showing expected location of landing zone

Looks pretty close-in -- lofted trajectory?

I don't believe it is necessarily an indication of a lofted trajectory.  Just that the stage will have *almost* enough energy left at MECO to get back to the launch site.  Almost.

Okay, so this would imply that there will be a long boostback burn, just not *quite* as along as it would be for RTLS...

[Kim Keller]

Why the 45-day gap for InSight's launch (April 27 through June 9)?

It would only be a 45-day standout if InSight launches on the last possible day (or is scrubbed on the last possible day). Insight is another NASA launch that uses the same NASA team, so they can't work both launches at the same time. Insight has priority given its smaller launch window.

Not really the same NASA team. Different rocket types, different people with the same skill sets assigned accordingly. Personally, I'm assigned to Atlas/InSight, Pegasus/ICON and Delta 4/PSP. I'm switching between missions on an almost hourly rate. This situation is just the fallout of other cross-trained folks' vacation scheduling & mission assignments.

[guyw]

Hawk is showing up on MarineTraffic.Com showing expected location of landing zone

Looks pretty close-in -- lofted trajectory?

I don't believe it is necessarily an indication of a lofted trajectory.  Just that the stage will have *almost* enough energy left at MECO to get back to the launch site.  Almost.

Okay, so this would imply that there will be a long boostback burn, just not *quite* as along as it would be for RTLS...

The press kit timeline mentions both an entry burn and a landing burn for the first stage, but says nothing about a boost back burn.

[JoerTex]

Hawk is showing up on MarineTraffic.Com showing expected location of landing zone

Looks pretty close-in -- lofted trajectory?

I don't believe it is necessarily an indication of a lofted trajectory.  Just that the stage will have *almost* enough energy left at MECO to get back to the launch site.  Almost.

Okay, so this would imply that there will be a long boostback burn, just not *quite* as along as it would be for RTLS...

The press kit timeline mentions both an entry burn and a landing burn for the first stage, but says nothing about a boost back burn.

It's landing on the drone ship which is downrange.