SpaceX Falcon 9 v1.1 CASSIOPE Launch Thread

[Faark]

I agree with Shifty. "Awaiting vessel downlink" most of the time. More ground / non vessel footage during early flight would have been nice. And live coverage of the first stage getting close to "lithobreaking" would have been awesome. At least thats what i was primarily watching for.

Congratz to SpaceX, but i am a little disappointed#. Hope they at least release a lot of videos later.

[Mr Shifty]

It hasn't happened yet.

CASSIOPE deployment was at T+14:15. POPACS at T+17:45, CUSat 1&2 at T+20:25, DANDE at T+21:25. All should have already occurred.

EDIT: It seems that they don't have global ground station coverage, so they have to wait for a ground station pass before they can confirm successful S/C sep. Should be in a few minutes.

[Scotius]

Awwww maaannn! I missed everything

[Mr Shifty]

CASSIOPE team reports that they're in contact with the spacecraft and it checks out. Congrats to SpaceX for a successful maiden voyage!

[bigdad84]

Sooooo, how did the propulsive landing over the water go?

[Francesco]

Sooooo, how did the propulsive landing over the water go?

not well, apparently: https://twitter.com/elonmusk/status/384407846349062144

but at least they've got some experience now. next flight, maybe they will slap some fins on the first stage

[Mr Shifty]

not well, apparently: https://twitter.com/elonmusk/status/384407846349062144

Actually it went pretty well. They were able to re-light the first stage engines twice: once to slow it down and again to attempt landing. Pretty impressive for a first attempt I'd say. Note that when they have landing legs on the rocket, it will be more resistant to rolling.

They won't be doing first stage re-entry tests on the next two flights so that they can give maximum reliability for SES-8 and Thiacom-6. Next re-entry test will be for the CRS-3 flight tentatively planned in February. They're pretty confident they can get re-entry of the first stage to work before the end of 2014, to the point that they're working out a landing pad for the stage with the FAA and Air Force possibly at the eastern tip of Cape Canaveral.

Second stage re-light had some (unspecified) problems this launch, but they'll be resolved before the SES flight (which will require re-light for GTO insertion.)

Most of this info from tweets posted by Jeff Foust of Elon Musk telecon this afternoon:

https://twitter.com/jeff_foust

Edited September 29, 2013 by Mr Shifty

[Faark]

They won't be doing first stage re-entry tests on the next two flights so that they can give maximum reliability for SES-8 and Thiacom-6.

Doesn't that mean they will change sth on the software compared to this launch? Thought maximum reliability means not changing anything and just doing the same splashdown-tests again^^

Btw, why do they want to only use the center engine? Is simultaneously re-lighting those engines that difficult? Since using 4 of the outer engines would increase the TWR and could allow control to prevent rolling...

[bigdad84]

Wouldn't the landing legs that the first stage is going to eventually have, be able to act as "fins" to some extent?

[Mr Shifty]

Doesn't that mean they will change sth on the software compared to this launch? Thought maximum reliability means not changing anything and just doing the same splashdown-tests again^^

Btw, why do they want to only use the center engine? Is simultaneously re-lighting those engines that difficult? Since using 4 of the outer engines would increase the TWR and could allow control to prevent rolling...

The depleted first stage has -- I've read somewhere -- a TWR of around 3 with a single Merlin 1D. Those engines can only be throttled to 70%. Landing will be difficult enough with one engine; even harder with more than one.

[Tommygun]

Damn, I forgot about this.

I had planned to take pictures from my house.

[czokletmuss]

Video from Falcon 9v1.1 start

[magnemoe]

Actually it went pretty well. They were able to re-light the first stage engines twice: once to slow it down and again to attempt landing. Pretty impressive for a first attempt I'd say. Note that when they have landing legs on the rocket, it will be more resistant to rolling.

They won't be doing first stage re-entry tests on the next two flights so that they can give maximum reliability for SES-8 and Thiacom-6. Next re-entry test will be for the CRS-3 flight tentatively planned in February. They're pretty confident they can get re-entry of the first stage to work before the end of 2014, to the point that they're working out a landing pad for the stage with the FAA and Air Force possibly at the eastern tip of Cape Canaveral.

Second stage re-light had some (unspecified) problems this launch, but they'll be resolved before the SES flight (which will require re-light for GTO insertion.)

Most of this info from tweets posted by Jeff Foust of Elon Musk telecon this afternoon:

https://twitter.com/jeff_foust

As I understand the recovery testing takes place after the second stage is away so it should not affect the primary mission.

Two exceptions: it's capacity problems controlling both stages at once or more probably they want to burn the first stage dry to get more dV reserves for second stage (we all know that extra dV is rarely an bad thing)

It might also be that they would have to do some redesign or other changes before its become interesting doing it again. One year time frame for making an reusable first stage is tight margin.

[Bunsen]

As I understand the recovery testing takes place after the second stage is away so it should not affect the primary mission.

Two exceptions: it's capacity problems controlling both stages at once or more probably they want to burn the first stage dry to get more dV reserves for second stage (we all know that extra dV is rarely an bad thing)

It might also be that they would have to do some redesign or other changes before its become interesting doing it again. One year time frame for making an reusable first stage is tight margin.

I think the problem is the less-efficient trajectory needed for first stage recovery, where the first stage's horizontal velocity is kept lower. Those payloads are probably heavy enough that flying a recoverable ascent profile would leave an insufficient propellant safety margin. You never plan on burning the tanks dry for the primary mission, but you keep the option around in case something else goes wrong or to serve a secondary payload.

SpaceX CRS-1 is a good example of this -- an engine failure made the first stage less efficient, and some of the propellant margin in both stages was consumed to compensate. That marginal capability had been sold, with the risks understood, to a secondary customer (Orbcomm wanted to test a prototype satellite). If everything had worked correctly, the second stage would have had plenty of leftover propellant after dropping off the Dragon, and would have carried that secondary payload to its intended orbit. When the primary mission ate into the safety margin, the secondary mission lost out and their satellite was left in an unusable state (so low that it deorbited in a few days).

[magnemoe]

I think the problem is the less-efficient trajectory needed for first stage recovery, where the first stage's horizontal velocity is kept lower. Those payloads are probably heavy enough that flying a recoverable ascent profile would leave an insufficient propellant safety margin. You never plan on burning the tanks dry for the primary mission, but you keep the option around in case something else goes wrong or to serve a secondary payload.

SpaceX CRS-1 is a good example of this -- an engine failure made the first stage less efficient, and some of the propellant margin in both stages was consumed to compensate. That marginal capability had been sold, with the risks understood, to a secondary customer (Orbcomm wanted to test a prototype satellite). If everything had worked correctly, the second stage would have had plenty of leftover propellant after dropping off the Dragon, and would have carried that secondary payload to its intended orbit. When the primary mission ate into the safety margin, the secondary mission lost out and their satellite was left in an unusable state (so low that it deorbited in a few days).

Understand, now I don't think they need the slower gravity turn for this tests it would be an splashdown anyway. However the atmospheric reentry will be different with higher horizontal speed and might not work or be relevant.

As I understand if the reusable get engine out they will switch to non reusable flight plan.

[Superluminaut]

I think the problem is the less-efficient trajectory needed for first stage recovery, where the first stage's horizontal velocity is kept lower. Those payloads are probably heavy enough that flying a recoverable ascent profile would leave an insufficient propellant safety margin. You never plan on burning the tanks dry for the primary mission, but you keep the option around in case something else goes wrong or to serve a secondary payload.

Hey I would love to know your resource on the falcon 9 reusable trajectory.

[Lunniy Korabl]

Anyone got any info about the alleged explosion of the upper stage after satellite release? Jim Edwards' article reads like a smear campaign and seems to confuse the upper and lower stages, but the reported debris orbits by Zarya combined with Elon's tweet about upper stage venting of liquid oxygen creating a fast moving fuzzy white sphere in space over SA suggest that something unusual happened.

Edited October 1, 2013 by Lunniy Korabl
moved an apostrophe

[rodion]

Anyone got any info about the alleged explosion of the upper stage after satellite release? Jim Edward's article reads like a smear campaign and seems to confuse the upper and lower stages, but the reported debris orbits by Zarya combined with Elon's tweet about upper stage venting of liquid oxygen creating a fast moving fuzzy white sphere in space over SA suggest that something unusual happened.

Well, it is quite depressingly common with many launch vehicles, many of the largest debris-creating events in spaceflight history were caused by used upper stages exploding, comparable to satellite malfunctions and the like. What does the article say about it, exactly?

[Lunniy Korabl]

http://www.businessinsider.com.au/report-explosion-on-elon-musks-spacex-rocket-falcon-9-2013-10

http://www.zarya.info/blog/?p=1595

Actually, it's the Zarya article that claims the intermittent video & audio feed during launch was SpaceX censorship due to a visible engineering issue on the 2nd camera angle. A bizarre leap to make considering the difficulty of getting a decent live video feed even when not strapped to a rocket. Between the two of them, it hardly seems like an unbiased account of events, but time will tell.

[Kryten]

Elon tweeted; quoted in tweet by Jeff Foust;

Musk: attempted relight of upper stage, encountered anomaly. Understand what it is and will fix before next flight. #falcon9

So it looks like we both have effective confirmation and a candidate for understatement of the year.

Edited October 1, 2013 by Kryten

[Meithan]

About the alleged second stage explosion, Mashable quoted Elon Musk's written response to their article:

"There was definitely no explosion of any kind," wrote Musk. "Falcon 9 released all satellites safely in their intended orbits. During venting to safe the stage, some foil insulation on the engine came loose. This is very lightweight, so will quickly reenter and burn up, but it is reflective on radar."

[magnemoe]

About the alleged second stage explosion, Mashable quoted Elon Musk's written response to their article:

Makes some sense, most common reason for explosions of upper stages is then liquid oxygen or other gasses boils off and generate high pressure in the tanks, should hardly be time for the LOX to boil off yet.