Author Topic: SpaceX McGregor Testing Updates and Discussion (Thread 4)  (Read 308470 times)

Offline Oersted

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #320 on: 09/26/2016 09:03 PM »
We'll know tomorrow.

Offline S.Paulissen

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #321 on: 09/27/2016 08:10 AM »
Can any inference be made from comparing the raptor test's flame color to the BE-4 test's flame color?  Because it's pretty striking how much bluer the BE-4's is.  I'm aware photographers take their liberties with color curves but it's really pretty big difference. 

Would a heavily CH4 rich burn be more carbon-y yellow flame compared to stoichiometric flames?

Can this be attributed to a FFSC cycle with more complete burn of propellants before exiting the nozzle (doubtful)?
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Offline DJPledger

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #322 on: 09/27/2016 08:23 AM »
Can any inference be made from comparing the raptor test's flame color to the BE-4 test's flame color?  Because it's pretty striking how much bluer the BE-4's is.  I'm aware photographers take their liberties with color curves but it's really pretty big difference. 

Would a heavily CH4 rich burn be more carbon-y yellow flame compared to stoichiometric flames?

Can this be attributed to a FFSC cycle with more complete burn of propellants before exiting the nozzle (doubtful)?
Different atmospheric conditions can affect the color of the flame. Looks like the Raptor test fire was done in humid conditions which I think make flames more pink/orange in color. Also it was fired in the dark which makes the pink/orange glow much more visible. Raptor test firings in daylight should give a much more blue looking flame.

Online cartman

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #323 on: 09/27/2016 08:43 AM »
I think the white balance setting of the camera will make a larger difference, especially in these night photos.

Offline wannamoonbase

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #324 on: 09/27/2016 01:00 PM »
It maybe a throttled down test, and likely not at optimum ratios yet. 

It's the first firing after all.  I wouldn't be surprised if this was the equivalent of a car show when they get an engine to fire with a squirt of gas into the carburetor  and not water pump or radiator.

Give them some time to get use to the new toy before reading into things.
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Offline JamesH65

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #325 on: 09/27/2016 04:42 PM »
It maybe a throttled down test, and likely not at optimum ratios yet. 

It's the first firing after all.  I wouldn't be surprised if this was the equivalent of a car show when they get an engine to fire with a squirt of gas into the carburetor  and not water pump or radiator.

Give them some time to get use to the new toy before reading into things.

Quite. Reading anything into the first try of anything with only one picture to go on would be foolish.

Offline Mike_1179

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #326 on: 09/27/2016 05:18 PM »
How do you think this test would sound compared to a normal Merlin test?

There were no warnings to locals about "louder than normal" tests prior to this. To be fair, the locals don't generally complain about single engine tests that happen all the time and the fire-y end is pointed away from town.

Offline RoboGoofers

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #327 on: 09/27/2016 05:33 PM »
How do you think this test would sound compared to a normal Merlin test?

There were no warnings to locals about "louder than normal" tests prior to this. To be fair, the locals don't generally complain about single engine tests that happen all the time and the fire-y end is pointed away from town.

when they warn of "louder than normal" I assume this has meant, up to now, "longer than normal". I'd also assume this was a quick firing just to make sure it works. it'd still be louder than normal for a single merlin, but not as loud as  a falcon test fire, so it's likely they won't issue warnings.
« Last Edit: 09/27/2016 05:36 PM by RoboGoofers »

Offline gongora

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #328 on: 09/27/2016 05:42 PM »
The "louder than normal" tests were mostly the firings of F9 on the raised test stand.  SpaceX seems to be taking noise abatement into account more as they build new test stands.

Offline Dante80

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Offline deruch

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #330 on: 10/01/2016 11:11 PM »
https://twitter.com/SpaceX/status/780862107478654976

8 second test.

Just to be sure people realize, if you're not hearing anything when you play the video clip, you can turn the sound on by clicking on the speaker icon in the bottom right of the video [LOUD Warning].
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Online docmordrid

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #331 on: 10/02/2016 01:40 AM »
Someone put it on YouTube

DM

Offline DOCinCT

Can any inference be made from comparing the raptor test's flame color to the BE-4 test's flame color? 
The Blue Origin video is from Feb 2016; in Sept 2016 Tory Bruno said ULA was waiting on  a full-scale static firing of the BE-4.
So what was BO testing in Feb?   Is this in the same category of a "scale" Raptor engine that SpaceX tested?

Offline RedLineTrain

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #333 on: 10/02/2016 07:29 PM »
Musk said it was a "full up test," so I assume that it was a test of the full engine.  But that would mean that they skipped the intermediate steps that Blue Origin did.

Offline jg

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #334 on: 10/02/2016 07:59 PM »
Musk said it was a "full up test," so I assume that it was a test of the full engine.  But that would mean that they skipped the intermediate steps that Blue Origin did.

You don't know that.

SpaceX has been testing parts of the engine at Stennis for at least a year or two.  This is just the first test of the full engine, but parts of it have been under test for quite a while.

https://www.nasa.gov/press/2014/april/nasa-spacex-cut-ribbon-to-launch-testing-partnership

Offline RedLineTrain

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #335 on: 10/02/2016 08:09 PM »
So what was BO testing in Feb?   Is this in the same category of a "scale" Raptor engine that SpaceX tested?

The factsheet that Blue Origin put out at the time described it as "BE-4 subscale testing of an oxygen-rich preburner, staged combustion of the preburner, and the main injector assembly."

Online AncientU

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #336 on: 10/02/2016 11:21 PM »
So what was BO testing in Feb?   Is this in the same category of a "scale" Raptor engine that SpaceX tested?

The factsheet that Blue Origin put out at the time described it as "BE-4 subscale testing of an oxygen-rich preburner, staged combustion of the preburner, and the main injector assembly."

List sounds similar to components SpaceX was testing at Stennis in 2014.
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Offline gongora

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #337 on: 10/05/2016 03:20 PM »
SpaceNews: SpaceX’s Shotwell on Falcon 9 inquiry, discounts for reused rockets and Silicon Valley’s test-and-fail ethos


From Q&A with Gwynne Shotwell
Quote
Q: The first stage recovered from the JCSat-14 launch, a mission to GTO, has now been put through eight ignition sequences in Texas, with two more to go. Then what happens?

A: Then we put that vehicle to rest. That actually is the qual [qualification] vehicle. That vehicle will basically have served its purpose. It just gives us confidence. You know, you can qualify a vehicle with increased margin, or amplitude, or with increased duration. The testing we were doing in Texas was a little bit of both.

The thrust we were testing for about half those mission durations was higher than we flew it, and we wanted to get 10 life cycles on that vehicle that we had flown before.

I guess they're also using that vehicle to qualify the  thrust upgrade.

Offline Chris Bergin

Local observations of a Falcon 9 test firing at McGregor, provided to L2. Thinking it was a second stage, but they aren't sure.

They are ramping up ahead of RTF.

Posting here as we don't know for sure which mission this stage will be involved with.
« Last Edit: 11/03/2016 04:53 PM by Chris Bergin »

Online abaddon

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Re: SpaceX McGregor Testing Updates and Discussion (Thread 4)
« Reply #339 on: 11/03/2016 08:09 PM »
Is it usual for SpaceX to do second stage firings, or is this a new thing (if true)?
« Last Edit: 11/03/2016 08:10 PM by abaddon »

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