First shuttle main engine fully assembled at KSC

[drwayne]

From SpaceFlight Now:<br /><br />http://www.spaceflightnow.com/news/n0408/07ssme/<br /><br />Wayne<br /> <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[the_ten]

Now if only they would put the entire shuttle(s) back together and quit acting scared of progress.

 

[propforce]

Many posters are quick to type from both end of their mouths without understanding the problems first. <div class="Discussion_UserSignature"> </div>

 

[propforce]

<i>"..... The transfer of SSME assembly operations to KSC has enabled the reduction of infrastructure at Rocketdyne's Canoga Park facility, and enhancement of engine processing capability at KSC,...."</i><br /><br />Same reason why the RS-68 is assembled near Stennis, all in a move to reduce cost and head-count at Canoga Park.<br /><br />I am not sure this is a good trend (decisions by the MBAs?). The reality is that you can not separate products from engineerings without suffering a loss of know-how on both sides. Old engineers can not walk to the shop floor and understand what is the problem, and young engineers will no longer understand how hardware are built. Both side will increasing manage their 'problems' by specifications rather than by communication and working together.<br /><br />But I'd reckon the whole point of my rant is moot if the Shuttle is to be scrapped in 8 years <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> </div>

 

[lunatic133]

At least progress is being made. I too am anxious to get the Shuttle flying again but not at the expense of losing another. The workers in Florida know what they're doing.

 

[SpaceKiwi]

I think I understand the underlying reasons why much of the US space industry work is divvied up around the country (ie. everyone gets a piece of the cash pie), but it does kinda amaze me that the engine is now shipped to Mississippi for acceptance testing.<br /><br />In an ideal world, that would surely not be the preferred way of going about this. I'm sure most of those concerned with building and operating these marvelous power-plants would prefer any travelling to be largely confined to almost vertically upwards, strapped to the back of an Orbiter?<br /><br />I understand Miss' is where the testing facility is, but it just strikes me that this is the kind of "un-optimal" methodology that the Shuttle program can well do without. Especially when the public microscope is already focused on RTF efforts, and the Shuttle is hellishly difficult to operate successfully at the best of times. <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[propforce]

The design of SSME, as well as any engines and rockets, are designed to meet the ground transportation loads. In addition, there are ground support equipment (GSE) to hold the engines in place and minimize those loads. So it is largely not a concern as far as its wear on the engine. <br /><br />The engine has been historically assembled in Rocketdyne's facility in Canoga Park, California, with many key manufacturing processes at the same location as well. Recently there's a move to take all production work out of California, mainly due to the increasing stringent environmental regulations here, as well as reducing labor cost (different 'market rate' between California and Florida/ Mississipi). <br /><br />Another factor is customer-driven, e.g., NASA in this case, who wants to have more control closer to its locations. Afterall, the orbiter maintenance & repair is being done in the OPF, and the SRB is stacked in the VAB, so why shouldn't the SSME be assembled & checked out at KSC as well? <div class="Discussion_UserSignature"> </div>

 

[SpaceKiwi]

Yeah I totally understand and agree with all the good, sensible, logical points you make, propforce. I was just thinking about the "bigger picture" so to speak.<br /><br />I personally think it is a great advancement that the engines are now assembled on site, as well as the moves to bring the Orbiter maintenence across from California. I just think it is a "shame" that the engines can't also be tested on site at KSC. I guess that would appeal more to my sense of "tidyness" about how things could be done. I know every possible precaution is taken in the transportation of space hardware, but there is a little part of me dreading the day when I hear a freight car has derailed or a barge sinks, etc.<br /><br />But, again, what you say is quite right. Life has never been optimised in the way I describe, so it follows it would be no different for the space program.<br /><br />As a foreigner hoping to visit KSC one day, having everything centralised there sure makes for a nice thought though! Imagine being able to see every aspect of the shooting match in the one place, from processing to launching to engine assembly and testing. Now that's a "theme-park" I'd like to visit! <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[najab]

><i>I just think it is a "shame" that the engines can't also be tested on site at KSC.</i><p>The hundreds of millions of dollars that would have to be invested in building test stands wouldn't be offset by the few tens of thousands of dollars in saved transportation costs.</p>

 

[the_ten]

Nobody has suggested to be reckless with the remaining shuttle fleet. HOWEVER, you can NOT eliminate risk & loss of life. The shuttles have an overwhelmingly high rate of success. People seem to have forgotten that and it's not as if the vehicles 'arnt' well-cared for after every mission. <br /><br />I am a taxpayer therefore I have contributed to a portion of that 3.5 BILLION DOLLAR price tag. I am entitled to an opinion and I will never apologize for having one. It IS my opinion that NASA is not as aggressive as *I THINK* they should be. Afterall, with all those billions of dollars being spent, I would like something more than reports on safety and cancelled projects. Thank god for the Mars rovers. They are the only thing saving NASA's ass right now.<br />

 

[the_ten]

<font color="yellow">"I think you are being too generous. 2 failures out of only 112 launches is not "overwhelming high rate of success"</font><br />=====<br />97.76% success is pretty high in my book. <img src="/images/icons/smile.gif" />

 

[najab]

><i>97.76% success is pretty high in my book.</i><p>For cargo rockets, maybe. But consider that the two failures means 14 dead astronauts. That's not so good.</p>

 

[the_ten]

23 years in service, 112 flights, 2 failures resulting in 14 dead. And 300,000 people die in the United State PER YEAR of morbid obesity.<br /><br />Which do you think is more of a risk to your health, flying on a shuttle mission or supersizing your french fries at McDonalds?<br /><br />While I'm not exactly enthusiastic about the 'higher ups' at NASA, judging by some of what I've read here alerts me that, YES, there are worse people for the job... And thank god they don't have it!

 

[lunatic133]

I'm afraid I have to be the devil's advocate here. On one hand I know that the shuttle must be made as safe as possible, but on the other hand, risk aversion is a disease that claims far more important things than lives. The fact is that, to explore the new frontier, people are going to die. To not accept this fact is to instead accept stagnation. I would gladly go out there tomorrow even if i knew that there was only a 10% chance I would return -- however on the other hand, if I knew that there could be a much higher chance of survival, but there wasn't, because nobody paid attention to safety, I might be a little upset. Risk should be minimalized TO THE BEST EXTENT IT CAN BE ... But that does not mean attempting to eliminate it altogether. Does that make sense?

 

[the_ten]

<font color="yellow">"I'm afraid I have to be the devil's advocate here. On one hand I know that the shuttle must be made as safe as possible, but on the other hand, risk aversion is a disease that claims far more important things than lives. The fact is that, to explore the new frontier, people are going to die. To not accept this fact is to instead accept stagnation. I would gladly go out there tomorrow even if i knew that there was only a 10% chance I would return -- however on the other hand, if I knew that there could be a much higher chance of survival, but there wasn't, because nobody paid attention to safety, I might be a little upset. Risk should be minimalized TO THE BEST EXTENT IT CAN BE ... But that does not mean attempting to eliminate it altogether. Does that make sense?"</font><br />=====<br />Exactly! I raise my glass to you, sir.

 

[lunatic133]

Thank you! However, I am not a sir <img src="/images/icons/wink.gif" />

 

[propforce]

She's a very pretty Ma'am <img src="/images/icons/cool.gif" /> <br /><br />edited out the spur of moment outburst <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> </div>

 

[SpaceKiwi]

Well, let's hope the engine tests fine and we are one step closer to RTF.<br /><br />Two questions for the informed. How many engines have not shined in the acceptance testing? I assume even with such magnificant machinery, you will get the odd "dicky" engine.<br /><br />Second, are they all "Block 3" engines now? I know they were progressively introducing them a couple of years or more back. Has the down-time allowed the modifications to be made across the entire compliment of engines? <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[propforce]

I am the 'semi-informed' but I'll tell you what I know.<br /><br />The current engines are Block II, or Block II-A (not sure). The main difference from Block I to Block II is a larger throat combustion chamber while keeping the nozzle exit diameter and length the same. As a result, Block II has a slightly lower chamber pressure (Pc) and a lower nozzle exit area ratio. But I believe the sea level thrust is approx the same. Block II also has upgraded LO2 and LH2 turbopumps.<br /><br />The difference between Block II and IIA is that the IIA is a 'semi-upgrade' from the Block I, except only with the LO2 turbopump. I think P&W was having trouble with the new LH2 turbopump design at the time.<br /><br />Now typically in engine acceptance testing, there will be allowance for a manximum of X number of hotfire before you need to take the engine down, and fix the component, e.g., turbopumps, preburners, or MCC injectors that are not performing to spec. For SSME, the acceptance testing is a full mission duration hot fire -- that is approx 10 minutes long. I was fortunate to have witness one of the engine ATP at Stennis and was very impressed with its power <img src="/images/icons/cool.gif" /> <div class="Discussion_UserSignature"> </div>

 

[the_ten]

<font color="yellow">"Thank you! However, I am not a sir"</font><br />=====<br />Oops, sorry about that! I didn't know.

 

[SpaceKiwi]

Thanks prop and SG. As soon as I typed Block III, I had a feeling I wasn't quite correct with the name. I was working off memory of the NASA TV commentary, where I think the main improvement repeatedly mentioned was the new turbopump design. It's interesting to know it wasn't limited to just that modification.<br /><br />So, coming back to my original question, are you aware if they will be flying all Block II-A's on RTF? I guess the plan would have been to phase the upgrades in across the entire compliment of engines as time and finances permit. Despite the fact the SSME department has had this enforced down-time, I imagine they would still be working to a budget as to when they can make the mods?<br /><br />Again, IIRC the Block II-A was highlighted in the commentary as a more efficient design and I think, by implication, a "safer" design. Hopefully they will be able to fly a trio of them each time from now on. <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[radarredux]

> <i><font color="yellow">The future Shuttle flights will use the bock II engines which are more advanced than the Block IIA engines.</font>/i><br /><br />Reminds me of the IEEE 802.11b standard coming <i>before</i> the 802.11a standard. <img src="/images/icons/smile.gif" /></i>

 

[propforce]

I found this AIAA paper (AIAA 2002-3758) which gave a good summary of SSME upgrades. <br /><br />I took a shot of the summary figure, hope this comes out readable...<br /> <div class="Discussion_UserSignature"> </div>

 

[propforce]

From the same paper.... <br /> <div class="Discussion_UserSignature"> </div>

 

[propforce]

Thanks Calli for approving these pics <img src="/images/icons/cool.gif" /><br /><br />Apparently no moderators were on-duty over the weekend. <img src="/images/icons/tongue.gif" /> <div class="Discussion_UserSignature"> </div>