SpaceX Merlin 1C Engine

[Comga]

Jim - 21/3/2008  10:25 AM

Comga - 20/3/2008  11:47 PM
It looks like the Saturn 1B used single axis steering on each of its eight engines. Can anyone confirm or refute this?

inner four were fixed and the outer four had 2 axis steering

Thanks, Jim
I was basing my assumption on the image shown in an old SpaceX update, and what I remember seeing in the "Rocket Garden" at KSC two years ago.  

If only the outer four engines gimbal, and do so in two axes, it is not clear what those horse-collar shapes are where each of the eight engines projects through the rear surface.

[Antares]

Water + rocket engines.  There's this
http://www.boeing.com/news/releases/1996/news.release.960827a.html

An injector is pretty expensive as well since there's a lot of machining and intricate manufacturing and welding that goes on.  If you allowed water intrusion into the nozzle and chamber, it would back flow up to the valves unless you could capture a bubble and do so repeatedly.

[Jim]

Comga - 1/4/2008  12:49 AM

If only the outer four engines gimbal, and do so in two axes, it is not clear what those horse-collar shapes are where each of the eight engines projects through the rear surface.

Access to remove and replace engines

[marsavian]

A video is worth a thousand pictures

http://video.google.com/videoplay?docid=6461477885976703694&q=SpaceX+%28site%3Avideo.google.com+OR+site%3Ayoutube.com%29&hl=en-US

[Comga]

The "burp" at shut-down is quite evident here, as it was in the nine engine test video.  I don't remember it in the videos of the Merlin 1A tests.  Is this really benign?

[zeke01]

The "burp" at shut-down is quite evident here, as it was in the nine engine test video.  I don't remember it in the videos of the Merlin 1A tests.  Is this really benign?

As explained elsewhere, the thrust decay is slower in the 1C due to fuel in the regen nozzle being burned off.  If Merlin 1A uses the ablative nozzle, thrust termination is faster because there's much less residual fuel in the plumbing downstream of the valves to burn off.

Old clips of the F-1 firings on the test stand show numerous 'burps' (or should be belches given their size! during shutdown, so it's certainly a known phenomenon.  The Saturns used SRMs to authoritatively separate the stages to overcome any residual thrust.

Benign?  Probably not if puny weak humans were standing next to them.  The burps/belches looked like explosions in the F-1 clips, but the hardware looked tuff enough to withstand them.

[A_M_Swallow]

I read that OSC would consider using the Merlin engine in the Taurus II.
See page 6 of
http://forum.nasaspaceflight.com/index.php?topic=11604.0

Rival firms negotiating over an engine could be fun to watch.

[Nate_Trost]

Even after they upgrade the turbopumps, Merlin doesn't have the thrust to replace the Aerojet engines.

[Jim]

I read that OSC would consider using the Merlin engine in the Taurus II.
See page 6 of
http://forum.nasaspaceflight.com/index.php?topic=11604.0

Rival firms negotiating over an engine could be fun to watch.

Wrong deduction and that is rumor mongering. 

1.  The merlin is not offered.  That is one of the reasons the NK-33 got chosen in the first place. 
2,  All that was basically said it that OSC would perform due diligence if the current supply of NK-33 were run out and Aerojet would have to start manufacturing them.  OSC would look at all the options. 
3.  there would be nothing to watch.  It would happen behind closed doors

[braddock]

I read that OSC would consider using the Merlin engine in the Taurus II.
See page 6 of
http://forum.nasaspaceflight.com/index.php?topic=11604.0

This is distorted quite out of context.

Let's take great care to keep the comments of our more notable members in context.  We are very fortunate that they are here.  We have lost at least one notable personality in the past because someone ran off and blogged his post out of context.

[pippin]

I read that OSC would consider using the Merlin engine in the Taurus II.
See page 6 of
http://forum.nasaspaceflight.com/index.php?topic=11604.0

Rival firms negotiating over an engine could be fun to watch.

Read it again.
antonioe was replying to a comment by me, stating that WHEN NK33s RUN OUT (that's years from now) AND SpaceX is probably not really no longer a fierce competition the world might look different.
My comment was made in the light of an earlier comment I made in another thread stating that if SpaceX adds a few more failed launches to their track record they could end up as an engine manufacturer, since this is where they have developed the biggest asset.
antonioe was stating that if it was on the market and qualified they would seriously consider it BUT that both is not the case today.

BTW, OSC is buying their SRMs from a "Rival" firm today, aren't they?

[kevin-rf]

Well antonioe has made an official reply on the Taurus II and availability of the NK33 thread, page six by my count :

http://forum.nasaspaceflight.com/index.php?topic=11604.75

To quote him ...

Let me assure you that if

 1) the technical and QA characteristics and
 2) the price of the Merlin engines

are suitable for Taurus II, and

 3) SpaceX is interested in offering them to us,

we would consider it very seriously.  As of today, though, I don't know enough about that engine to even answer question 1.
[\QUOTE]

[FutureSpaceTourist]

Cross-post, Elon talks through Merlin 1C engine:

Today we're getting a history and engineering lesson with Elon Musk about SpaceX's Raptor engine. We talk about some of the early design decisions and how the engine has evolved.

Recommended videos to help with some context [Playlist] - https://youtube.com/playlist?list=PLWzKfs3icbT55w6f9wGqXkhk_SlanIhnr

Huge thanks to Ryan Chylinksi from Cosmic Perspective for helping shoot this video! - https://www.youtube.com/c/CosmicPerspective & http://patreon.com/cosmicperspective

00:00 - Intro
00:55 - Overview of Merlin
02:30 - Ablative Merlin
04:45 - Merlin 1C regen and spiral nozzle
09:35 - First Falcon 9 Flight Rotation
11:30 - Pintle Injector
17:00 - Outro

[wannamoonbase]

I watched the video over the weekend.  My take away was the importance of trying different approaches, learning and trying again.

Traditional rocket engine design and development is slow, takes years and billions and is hardware poor.  SpaceX tried a lot of things, broke things and moved fast. 

Knowing what not to do or try matters.

It was interesting to see that Elon, 12 years later, could so easily discuss details and why they tried things.  The dude is many things, including very intelligent.

[FutureSpaceTourist]

In the above interview Tom Mueller mentions that the Merlin 1C, developed for F9, was too powerful on F1 flight 3 for the F1 structures and so had to remain throttled for the flight. He said it stayed at sea level thrust so they had to throttle as it went to vacuum.