Updates SpaceX Falcon 9 F5 CRS SpX-2 through CRS SpX-12 Updates

[Cosmic Penguin]

I heard they are scrubbing the launch and they will try next year in January.

http://www.nasaspaceflight.com/2014/12/spacex-static-fire-falcon-9-crs-5/

Boo hoo boo hoo

And confirmed: http://www.nasaspaceflight.com/2014/12/spacex-static-fire-falcon-9-crs-5/

There's a high solar beta angle constraint around the new year that would have prevented the Dragon from parking there, which means there's no reason to launch until the period ends on January 7 anyway.

Well, one less launch in 2014 means one more in 2015.... :tiphat:

 

[Cosmic Penguin]

Have an all-rounded successful and record-breaking 2015 SpaceX! 5 days to launch!

 

[Urwumpe]

Interesting that nobody talks about the steerable "potato-masher" grid fins on the first stage - These had been tested on a grasshopper flight and seem to look promising to control the first stage during reentry and landing, so the next landing is not tumbling out of control.

Still, this of course made the first stage heavier again and costs more performance.

 

[Cosmic Penguin]

Interesting that nobody talks about the steerable "potato-masher" grid fins on the first stage - These had been tested on a grasshopper flight and seem to look promising to control the first stage during reentry and landing, so the next landing is not tumbling out of control.

Still, this of course made the first stage heavier again and costs more performance.

Which is why F9 flying in expendable mode is quite a hot rod (I mean, 13 tonne to LEO and 5+ tonnes to GTO with a 2 stage kerosene powered rocket without using staged combustion is.....quite something).

In other news, the weather forecast for tomorrow looks...pretty good.

Weather forecast for Titusville, Florida on January 6, 2015 (6 a.m.)

A few clouds. Low around 15C. Winds NNE at 10 to 15 km/h.

Time|Temps|Dew Point|Relative Humidity|Precip|Snow|Cloud cover|Pressure|Wind|Weather
6 AM|16°C|15°C|96%|2%|0%|42%|1026 hPa|3 km/h NNE|

Partly Cloudy

 

[Urwumpe]

Only weights 50 tons more than the Zenit 2 which has about the same performance, but with staged combustion and with way heavier empty masses of both stages... But $45,000,000 per launch in 1994...

 

[MaverickSawyer]

So what do you think would happen if they switched to a fuel-rich staged combustion cycle? (Forget reusing an ox-rich preburner setup. YOu'd probably have to rebuild the hot section after each flight... if it doesn't eat itself alive like an NK-33. )

 

[Urwumpe]

So what do you think would happen if they switched to a fuel-rich staged combustion cycle? (Forget reusing an ox-rich preburner setup. YOu'd probably have to rebuild the hot section after each flight... if it doesn't eat itself alive like an NK-33. )

Not that it makes much sense right now, but it sure would produce a much higher specific impulse and allow a much better performance. Also it would make the engines much lighter at the same thrust, since you could operate at five times the current chamber pressure without problems.

Please remember that a single NK-33 had a turbopump failure right now, while already almost 100 Russian rocket engines with ox-rich preburner flew successfully. That technology is not that bad at all.

And for reusability, it would already be enough if you could detach the turbopump block of a rocket engine with just a few screws and install a replacement block, while inspecting the old turbopump after a few flights. While this is already hard to achieve in terms of engineering, it could be cheaper than swapping a whole engine.

 

[MaverickSawyer]

Not that it makes much sense right now, but it sure would produce a much higher specific impulse and allow a much better performance. Also it would make the engines much lighter at the same thrust, since you could operate at five times the current chamber pressure without problems.

Hmmm... so they went with the Gas Generator cycle for reliability, not performance. Makes sense.

Please remember that a single NK-33 had a turbopump failure right now, while already almost 100 Russian rocket engines with ox-rich preburner flew successfully. That technology is not that bad at all.

Okay, I'll give you that on the account of the RD-170-derived engines. Those have proven to be highly reliable. But the NK-33 has had a few more problems... Antares was just the most public failure. There was a test firing at Stennis last year that was a catastrophic failure as well.

And for reusability, it would already be enough if you could detach the turbopump block of a rocket engine with just a few screws and install a replacement block, while inspecting the old turbopump after a few flights. While this is already hard to achieve in terms of engineering, it could be cheaper than swapping a whole engine.

Hmm... Not sure how the seals work on that kind of stuff, but I DO know that that could place added wear and tear on the mounting point. But that would allow them to decoke the cooling channels with relative ease before another flight.

 

[Urwumpe]

Hmmm... so they went with the Gas Generator cycle for reliability, not performance. Makes sense.

Also, its about controllability - a gas generator cycle engine can react a lot faster over a wide range of throttle settings without getting chaotic effects - other engine cycles either need more relaxed control (which makes them pretty rough and possibly instable) or slower reaction times.

Okay, I'll give you that on the account of the RD-170-derived engines. Those have proven to be highly reliable. But the NK-33 has had a few more problems... Antares was just the most public failure. There was a test firing at Stennis last year that was a catastrophic failure as well.

But that could have other causes, after that time in storage.

Hmm... Not sure how the seals work on that kind of stuff, but I DO know that that could place added wear and tear on the mounting point. But that would allow them to decoke the cooling channels with relative ease before another flight.

Well, you could also make a cheap expendable seal then. Who cares about an expensive $60 gasket if it saves you a $6 million rocket engine?

 

[Cosmic Penguin]

Here's the landing barge heading towards its launch position:

 

[Cosmic Penguin]

On the pad:

Notice the grid fins (which would be deployed at T+5 minutes according to the press conference earlier today, high above the atmosphere) on the 1st stage.... :hmm:

 

[Cosmic Penguin]

So what is on board the Dragon this time? Here's the list:

T-2 hours 15 minutes and counting.

 

[Cosmic Penguin]

T-1 hour. Weather is now 90% GO.

 

[ADSWNJ]

Launch in 12 mins. All Go at this time.

T-10... flight is armed, launch clock running....

T-6 mins ... now on internal power

T-4 mins ... gantry swinging back

ABORT at T-1.21 ... off-nominal condition in the upper stage. Scrubbed for today, due to the sub 1-sec launch window. Dammit!!

 

[Unstung]

There's a hold at T-1:21.

The launch was delayed until at least Friday the 9th. Come on.

 

[dman]

6:20 AM Eastern time - Fox news showed shot of Falcon on pad, said beem delay in count

 

[fsci123]

Aborted?

 

[Cairan]

:shrug:

 

[N_Molson]

Well, the ISS won't wait and is flying away. Aborted.

 

[dman]

Launch scrubbed - said problems in actuator, computer would have shutdown
the count if not scrubbed