SpaceX F9: Starlink v1 Flight 1 : November 11, 2019 - DISCUSSION

[baldusi]

Does such a long debris corridor (from Madagascar to New Zealand) implies that SpaceX is planning to test a new heat shield with this second stage?

It's the same as the first Starlink launch, so I'm guessing no?

https://forum.nasaspaceflight.com/index.php?topic=48135.msg1946062#msg1946062

May be they are doing burn to depletion and thus have a wider uncertainty margin?

[edzieba]

The last Starlink launch also lacked the acoustic tiles within the fairings.

Are you sure about that? I just looked at some pictures with Starlink 0.9 and it's fairing, and it looks like the tiles are in place in those pictures..

https://forum.nasaspaceflight.com/index.php?action=dlattach;topic=48135.0;attach=1560089;image

Also, it looks like it did static fire while payload/fairing were attached:

https://forum.nasaspaceflight.com/index.php?action=dlattach;topic=48135.0;attach=1560321;image

Look closely at the half-in-fairing photo, the tiles are not present. They are also .

[gongora]

Will the launch mass be the same as the Starlink v0.9 mission (18.5 US tons)?

If the individual satellites were anywhere near the stated mass then the first launch wasn't 18.5 tons no matter if you're doing metric or US short tons.  On the launch webcast they said the payload was 30,000 pounds.

[ZachS09]

Will the launch mass be the same as the Starlink v0.9 mission (18.5 US tons)?

If the individual satellites were anywhere near the stated mass then the first launch wasn't 18.5 tons no matter if you're doing metric or US short tons.  On the launch webcast they said the payload was 30,000 pounds.

I said 18.5 US tons because I saw on Raul’s General SpaceX Map that the launch mass for Starlink v0.9 was 16,783 kilograms, which converts to 18.5 US tons.

This, in turn, came from a tweet from Elon prior to that launch.

[JFARNS]

Does such a long debris corridor (from Madagascar to New Zealand) implies that SpaceX is planning to test a new heat shield with this second stage?

It's the same as the first Starlink launch, so I'm guessing no?

https://forum.nasaspaceflight.com/index.php?topic=48135.msg1946062#msg1946062

Maybe in case the satellites failed to separate and came down with the stage? 

[woods170]

Does such a long debris corridor (from Madagascar to New Zealand) implies that SpaceX is planning to test a new heat shield with this second stage?

It's the same as the first Starlink launch, so I'm guessing no?

https://forum.nasaspaceflight.com/index.php?topic=48135.msg1946062#msg1946062

Maybe in case the satellites failed to separate and came down with the stage? 

Bingo.

[CyndyC]

Will the launch mass be the same as the Starlink v0.9 mission (18.5 US tons)?

If the individual satellites were anywhere near the stated mass then the first launch wasn't 18.5 tons no matter if you're doing metric or US short tons.  On the launch webcast they said the payload was 30,000 pounds.

I said 18.5 US tons because I saw on Raul’s General SpaceX Map that the launch mass for Starlink v0.9 was 16,783 kilograms, which converts to 18.5 US tons.

This, in turn, came from a tweet from Elon prior to that launch.

I believe the explanation for exceeding 60 x 500.5 lbs is revealed in Tyler Gray's article on this website at https://www.nasaspaceflight.com/2019/11/spacex-fires-up-falcon-9-starlink-mission/ (emphasis mine):

Each individual satellite has a launch mass of 227 kilograms (500.5 pounds), making the total payload mass – not including the payload adapter or deployment mechanisms – add up to 13,620 kilograms (30,027 pounds). This matches the payload mass from the previous dedicated Starlink mission, which was the heaviest payload that SpaceX launched to date.

If the launch mass of v 0.9 and of v 1.0 truly match, then the addition of the Ka-band antennas aren't adding any significant mass, and I find it somewhat difficult to believe they wouldn't be adding at least half a ton, so maybe the design improvements took off some mass.

[ZachS09]

One more thing to point out: I saw some posts in the Starlink 0.9 Discussion Thread that talked about 40 to 50 kilograms of krypton propellant in each of the sats, which could be a factor to the "18.5 tons" I mentioned.

https://forum.nasaspaceflight.com/index.php?topic=47594.msg1946572#msg1946572

[CyndyC]

One more thing to point out: I saw some posts in the Starlink 0.9 Discussion Thread that talked about 40 to 50 kilograms of krypton propellant in each of the sats, which could be a factor to the "18.5 tons" I mentioned.

Except Tyler calls the 227kg/500.5lbs the "launch mass", and w/o the fuel the satellites would be useless, so seems the fuel might as well be included in the given figure, but that figure is no longer accurate either way.

According to starlink.com, each sat now weighs ~260kg = ~573lbs, so the design improvements and/or the addition of Ka-band antennas will add ~2 tons to the final payload

[gongora]

The easiest explanation is that Elon misspoke, but a lot of people would never accept that explanation.

[Jirka Dlouhy]

One more thing to point out: I saw some posts in the Starlink 0.9 Discussion Thread that talked about 40 to 50 kilograms of krypton propellant in each of the sats, which could be a factor to the "18.5 tons" I mentioned.

Except Tyler calls the 227kg/500.5lbs the "launch mass", and w/o the fuel the satellites would be useless, so seems the fuel might as well be included in the given figure, but that figure is no longer accurate either way.

According to starlink.com, each sat now weighs ~260kg = ~573lbs, so the design improvements and/or the addition of Ka-band antennas will add ~2 tons to the final payload

I think that this is not problem for Falcon 9 FT.

[gongora]

One more thing to point out: I saw some posts in the Starlink 0.9 Discussion Thread that talked about 40 to 50 kilograms of krypton propellant in each of the sats, which could be a factor to the "18.5 tons" I mentioned.

Except Tyler calls the 227kg/500.5lbs the "launch mass", and w/o the fuel the satellites would be useless, so seems the fuel might as well be included in the given figure, but that figure is no longer accurate either way.

According to starlink.com, each sat now weighs ~260kg = ~573lbs, so the design improvements and/or the addition of Ka-band antennas will add ~2 tons to the final payload

That change from 227 to 260 is very recent, I'm pretty sure I checked a few days ago and it was still 227.

[CyndyC]

The easiest explanation is that Elon misspoke, but a lot of people would never accept that explanation.

Back in early 2015 he was asked in a Reddit AMA how he had calculated the 50% chance of landing the first attempt, and he freely admitted it was a complete guess. I thought that was funny, that someone so smart could use an estimate off the top of his head and have it interpreted as a complex calculation. That's analogous to a woman known to be wealthy and getting away with wearing cubic zirconia.

[sferrin]

https://twitter.com/SpaceX/status/1193687615528042496

Team is go for launch of 60 Starlink sats tomorrow—heaviest payload to date, first re-flight of a fairing, and first Falcon 9 to fly a fourth mission. Watching 1 sat that may not orbit raise; if not, 100% of its components will quickly burn up in Earth’s atmosphere

I wonder why they think one of the satellites may not make it to it's proper orbit.  And if they have reason to believe that why not fix it? 

[terryy]

Will this batch of Starlinks have inter-satellite links?

[salpun]

I was expecting more black in the stack because of the train issue seen after launch, Guess the mitigation for that is not ready yet or different then expected.

[gongora]

Will this batch of Starlinks have inter-satellite links?

No

[Alexphysics]

One more thing to point out: I saw some posts in the Starlink 0.9 Discussion Thread that talked about 40 to 50 kilograms of krypton propellant in each of the sats, which could be a factor to the "18.5 tons" I mentioned.

https://forum.nasaspaceflight.com/index.php?topic=47594.msg1946572#msg1946572

40 to 50 kilograms of Krypton would be overkill for this system. They would need 10kg at most for the rest of their operations.

[groknull]

https://twitter.com/SpaceX/status/1193687615528042496

Team is go for launch of 60 Starlink sats tomorrow—heaviest payload to date, first re-flight of a fairing, and first Falcon 9 to fly a fourth mission. Watching 1 sat that may not orbit raise; if not, 100% of its components will quickly burn up in Earth’s atmosphere

I wonder why they think one of the satellites may not make it to it's proper orbit.  And if they have reason to believe that why not fix it? 

Operational costs may far outweigh the value of a single satellite.  Many costs for a delay: time and personnel for rollback, destacking, replacement, restacking, stack check, rollout; range costs; ASDS, tug, fairing catcher ship idle time costs (station keeping fuel, crew costs), etc.  Probably cheaper to leave a problematic satellite in the stack and launch it.

Some similarities to data center operations.  Disks (and sometimes servers) are often fail in place.  If something goes bad, it is cheaper to disable the component and leave it there than have someone replace it.  Servers get replaced every 18 months or so for power consumption reasons, so a failed component typically doesn't impact overall data center performance significantly or for very long.

[RedLineTrain]

One more thing to point out: I saw some posts in the Starlink 0.9 Discussion Thread that talked about 40 to 50 kilograms of krypton propellant in each of the sats, which could be a factor to the "18.5 tons" I mentioned.

Except Tyler calls the 227kg/500.5lbs the "launch mass", and w/o the fuel the satellites would be useless, so seems the fuel might as well be included in the given figure, but that figure is no longer accurate either way.

According to starlink.com, each sat now weighs ~260kg = ~573lbs, so the design improvements and/or the addition of Ka-band antennas will add ~2 tons to the final payload

That change from 227 to 260 is very recent, I'm pretty sure I checked a few days ago and it was still 227.

Indeed, the Wayback Machine's October 22 snapshot indicates a 227 kg mass.