Space X: Falcon 9 Five Engine Test Fire Release + Official Video

[kraisee]

I hope Space-X will release the up-close video of the test firing too.

And I wonder if it is a slow motion camera up there, like the old Saturn footage was...

Ross.

[Crispy]

Surely the whole point of the test stand being so tall is that you don't need a deflector? That's what I thought when I saw it: "ah, clever, they won't have to dig trenches and things with the rocket way up in the air like that"

[kevin-rf]

Surely the whole point of the test stand being so tall is that you don't need a deflector? That's what I thought when I saw it: "ah, clever, they won't have to dig trenches and things with the rocket way up in the air like that"

With it's height you do not have as much backpressure interferring with your readings giving you a more realistic test. I think that was more of the reason for making it so tall. You can also place a small deflector at the base of that thing and not even notice it in the pics. I really like the water curtains

Have they released any pics of the base of the test stand? That would answer the deflector question.

[dunderwood]

The concrete tripod was built by Beal Aerospace, not by SpaceX.

[tobi453]

Close Up Video:
http://mfile.akamai.com/22165/wmv/spacex.download.akamai.com/22165/PR42-002.asx

[stockman]

Close Up Video:
http://mfile.akamai.com/22165/wmv/spacex.download.akamai.com/22165/PR42-002.asx

Great find... thank you... To my untrained eye that closeup of the engines looked Really nice and stable.

thanks for posting that..

[Bret]

A question on the post test procedure..
would they leave all 5 engines on the pad and then add 4 more or will they take them down pick, inspect them and then install 9 engines.  I'm assuming they will include the 5 they just fired and then 4 new ones.

I am going to make an uneducated guess and say that they will take down the 5 engines to inspect them first.  There is a lot of valuable engineering data to be found in those engine parts post-firing.

[edkyle99]

I am going to make an educated guess and say that they will take down the 5 engines to inspect them first.  There is a lot of valuable engineering data to be found in those engines parts post-firing.

It may happen that way, but one historical reference suggests that they could just as easily keep all five engines installed.  The first Saturn I booster, SA-T, went through a very similar firing sequence at MSFC during 1960, though at a faster initial pace.  The first two-engine SA-T test (8 seconds) occurred on March 28, 1960.  Two more engines were added and the four-engine cluster was fired for 7 seconds on April 6.  Four more engines were added and all eight engines fired for 8 seconds on April 29.  Progressively longer eight-engine tests occurred every week or so after that, until the cluster fired for 121 seconds on June 15.

 - Ed Kyle

[Antares]

This isn't about certifying engines.  It's about MPS (Main Propulsion System).  There's no reason to take them down for inspection unless there's something going on in the MPS that would cause a change when adding engines.  About the only thing imaginable would be the condition of the inducers, which is probably inspectable without dismounting them.  Downstream of the pump everything would be the same.  Maybe external effects from running next to each other, but you don't have to dismount to inspect that.

[Bret]

... Maybe external effects from running next to each other, but you don't have to dismount to inspect that.

Great points! I shall revise my statement above to say UNeducated guess!  Thanks for the insights.

[ceauke]

Is it just me, or does the left most engine in that video seem to move (further away from the centre engine) towards the end of the video? Maybe it's because of an increase in brightness that the vid gets a bit destorted.

[edkyle99]

Is it just me, or does the left most engine in that video seem to move (further away from the centre engine) towards the end of the video? Maybe it's because of an increase in brightness that the vid gets a bit destorted.

A guess - we may be seeing the effect of the fractional side force caused by the gas generator exhaust.  The effect is probably magnified by the wide angle lens. 

 - Ed Kyle

[rsnellenberger]

A guess - we may be seeing the effect of the fractional side force caused by the gas generator exhaust.  The effect is probably magnified by the wide angle lens. 

 - Ed Kyle

Put your mouse pointer on the edge of the gas generator at the start of the video.  After the flash at startup, the generator has clearly shifted to the right by a bit; after the engines shut down, the edge returns to the pointer location.

[ceauke]

Put your mouse pointer on the edge of the gas generator at the start of the video.  After the flash at startup, the generator has clearly shifted to the right by a bit; after the engines shut down, the edge returns to the pointer location.

Ok. Very clear that it moves now.

I suppose it's significant nonetheless. On the pic on their website it seems like the turbine outputs don't all point in the same direction. It's not possible for me to see if it's symetric though for the 9 engines. (ie to cancel out eachother) In fact, the 4 courner ones seem like they will push the rocket to spin on its axis.

[edkyle99]

I doubt that engine steering was enabled during this test.  The engines would gimbal through the vehicle's center of gravity during a launch to compensate for off-axis forces, etc.

 - Ed Kyle

[aero313]

I doubt that engine steering was enabled during this test.  The engines would gimbal through the vehicle's center of gravity during a launch to compensate for off-axis forces, etc.

 - Ed Kyle

Not necessarily.  If you have active control of all engines, there is no need to take the cosine loss.  On the Delta II, the solids used fixed nozzles, so pointing through the GC made sense.  Of course, the CG moves as  you use propellant, so the pointing of the fixed nozzles is just an approximation anyway.

[jabe]

Curious..
regarding the pic of the 5 engines with the people "installing" the engines.
what would the gentleman be doing INSIDE the engine.  I'm not sure what the cross-section of the engine would look like but i didn't think there is much in there to "poke" at.
jb

[edkyle99]

Not necessarily.  If you have active control of all engines, there is no need to take the cosine loss.  On the Delta II, the solids used fixed nozzles, so pointing through the GC made sense.  Of course, the CG moves as  you use propellant, so the pointing of the fixed nozzles is just an approximation anyway.

It isn't necessary for each individual engine to point through the center of gravity, but the total net thrust force vector has to pass through the center of gravity unless a steering force is needed.

 - Ed Kyle

[jiggawo]

He's taking a photograph.

Curious..
regarding the pic of the 5 engines with the people "installing" the engines.
what would the gentleman be doing INSIDE the engine.  I'm not sure what the cross-section of the engine would look like but i didn't think there is much in there to "poke" at.
jb

[jabe]

mmm..Was i blind before or is this a new picture?  great picture..always wonders what the inside looked like   now for the upclose pictures