Talk:Space Shuttle

For discussion prior to August 29, 2006, see Talk:Space Shuttle program.

Design

Why is a single fuel tank used? Wouldn't performance have been increased by using two smaller fuel tanks and discarding one after another, much discarding the individual stages of a rocket one after another? Such an improvement in performance could have been used for making the area of the fuel tank(s) on the orbiter side safer. 85.176.110.198 18:37, 7 September 2006 (UTC)

I'm not an engineer, nor do I work on space systems. That said, the most likely reason is mass. Two smaller tanks would require more than one large tank. Each SLWT (super light weight tank, the most modern version) is ~29.25 tons, with a volume of 541,763 gallons (pressurized) of liquid gaseous fuels. The paint was removed from the tanks to save 600 pounds (0.3 tons). Any additional mass is a direct loss of payload. Just the fittings for a tank (external hardware, orbiter attachment fittings, umbilical fittings, electrical and range safety system) are 4.1 tons, and the shuttle's payload capacity is only 17.69 tons with the SLWT (less with the older tanks), so a second tank would mean losing a minimum of ~1/4 of the payload of the shuttle. The Dark 20:52, 21 September 2006 (UTC)

Edit to last - the payload I gave was for a mission to the ISS. Maximum payload is greater, but the shuttle is limited to lower orbits with higher payloads. The Dark 20:53, 21 September 2006 (UTC)

Unfortunately I'm not in the space program either. Granted, two tanks providing the same volume will be heavier than one but if half of that weight can be shed half way up, then perhaps the lifting capability would be better. For example if the total weight of the two (empty) tanks would be say 34 tons then the shuttle would weigh roughly 5 tons more on the launch pad. (Now I'm assuming it can still lift off with the extra weight but I should imagine it can since the lifting capability of a rocket is more about the weight it can put into whatever orbit, rather than if it will actually get off the ground.) So once half the fuel has been burnt the shuttle would shed 17 unnecessary tons and fly the rest of the way up with only one 17 ton tank instead lugging a 29 ton tank all the way up. —The preceding unsigned comment was added by 85.176.99.68 (talk • contribs) .

Yes, but even if it became lighter during the ascent phase, the additional 5 tons, along with the larger load of OMS and RCS fuel required for a higher orbit (~210 nautical miles) would still redure the payload capicity at liftoff.

Imagine if you filled an airplane so that it was at MTOW (max takeoff weight) and added an additional 5 tons. The airplane would not be able to get off the ground. Why? Because the airplane is overweight, and even if the extra 5 tons was jettisoned during the flight, it would not matter because it would not be able to get off the ground in the first place, because the engines don't produce enough thrust. It may not be the best example, but I hope it shows that even if the weight is reduced during the ascent phase, it dosen't matter because the shuttle probably wouldn't be able to get off of the ground, simply because the SSMEs and SRBs do not produce enough thrust to lift the additional weight.--206.193.252.13 (talk) 06:17, 31 December 2008 (UTC)

Not a good analogy. The airplane in your example uses its propulsion to generate lift to leave the runway; the thrust necessary for that is far less than the weight of the aircraft. The space shuttle stack propulsion must generate more thrust than its take-off weight to leave the launch pad. As long as the generated thrust is greater than the weight of the stack, the shuttle will leave the pad. The shuttle stack usual take-off weight is about 2/3 the thrust, so it is accelerated vertically at about 1 G, or ~ 32 feet per second per second. Even if the take-off weight were increased by 1000 tons, the shuttle stack could leave the launch pad, but would be accelerated vertically at only about 0.04 G, or ~ 1.2 feet per second per second. That acceleration would be far too low for a number of reasons, but still, the stack could rise. A difference in take-off weight of 20 tons or so would be trivial at lift-off, but could be crucial in reaching orbit.

Neonorange (talk) 23:35, 13 February 2009 (UTC)

Word case "shuttle" or "Shuttle"?

There seem to be some confusion on whether the word should be upper or lower case in the body of the article; right now, there are about an equal number of each. I would think that, with a few exceptions, all should be upper case. Leon7 16:25, 14 November 2007 (UTC)

Yep, it's a proper name in this case. 68Kustom (talk) 08:55, 3 March 2008 (UTC)

The craft's name is the proper noun (i.e. Atlantis). NASA's space shuttle page also seems to use lower case. 173.22.123.35 (talk) 20:42, 16 November 2009 (UTC)

OME vs. OMS

In the "fact sheet" portion of this article, it says, "Engines 2 OME". Shouldn't that be OMS? The text "OME" links to an article about OMS and there isn't any other mention of OME in either article. --Lance E Sloan (talk) 13:20, 8 January 2008 (UTC)

Maybe OME was some non-standard abbreviation for "orbital manuevering engine"? Then each orbiter has "2 OME, but just one OMS". I support changing the infobox to read, "2 (OMS)" or some such. (sdsds - talk) 15:52, 8 January 2008 (UTC)

Link is swindle

Track the Shuttle with Google Maps - Link is just fraud. Earning money with google ads (Link is currently deleted). I hope this stays so. Links is from "Tom Mangan's Fun With Google Maps" ?? —Preceding unsigned comment added by 134.106.235.53 (talk) 16:31, 11 February 2008 (UTC)

Maxiumum payload

Has there ever been a mission where maximum payload was necessary? 84.173.246.66 (talk) 10:33, 18 February 2008 (UTC)

ASAT

the asat page says all kinds of interesting stuff about the orbiter but I noticed there is very little military history on this page. specifically they say a lazer was fired at it by the USSR in 1984, and other discussions of the orbiter possibly being used as an offensive weapon. Does anyone know if these claims are at all true or not? I would love to hear more about these issues especially because I find it odd that there is so little on this page about the cold war aspect of the shuttle (as great as it is now) 72.0.180.2 (talk) 00:22, 25 February 2008 (UTC)

I see almost nothing on the ASAT page regarding the Space Shuttle. There is little offensive capability of the Shuttle that isn't achieved in ICBMs and/or Nuclear Bombers... not sure what you are getting at here? — BQZip01 — ^talk 01:27, 25 February 2008 (UTC)

"Testing resumed in 1976 as a result of the US work on the Space Shuttle. Elements within the Soviet space industry convinced Leonid Brezhnev that the Shuttle was a single-orbit weapon that would be launched from Vandenberg, maneuver to avoid existing anti-ballistic missile sites, bomb Moscow in a first strike, and then land." and also from the Terra-3 WP- "On 10 October 1984, Soviet Minister of Defence Dmitry Ustinov ordered the Terra-3 complex to fire a warning shot at the shuttle Challenger, in response to the U.S. Strategic Defense Initiative plans announced a year earlier, and the continued military use of the shuttle. (italics mine) Even though the shuttle was illuminated with a low-power laser, it caused malfunctions to on-board equipment and discomfort (possibly even temporary blinding) of the crew." so anyways who knows, but I do know that during the cold war MUCH of the orbiters mission was DoD related, and I think maybe someday the article could explain that a little more thoroughly. 72.0.180.2 (talk) 06:23, 25 February 2008 (UTC)

Junk link

The first external link, "Space Shuttle Video via Shuttlesource.com: Current status of shuttle missions" points to a site where you can't see any video unless you register by paying "6 Months $29.99 USD or 1 Month at $9.99 USD". —Preceding unsigned comment added by 88.22.118.138 (talk) 05:21, 7 March 2008 (UTC)

How does the Space Shuttle avoid (or account for) hypersonic shockwaves during its journey into orbit?

I posted this question over at the Talk:Hypersonic page, but I figure this also belongs here. -- kanzure (talk) 16:13, 9 March 2008 (UTC)

To get into earth orbit, people are telling me that you need to do Mach 25, and that the NASA Space Shuttle does in fact kick up to that speed. That's hypersonic. But what about the hypersonic shockwaves? NASA simulates their launches with OVERFLOW, a computer program for computational fluid dynamics, and as far as I can tell -- from reading Peter G. Buning's website -- there are no modified Navier-Stokes used in the program. The NS equations are known to fail beyond Mach 2 (or so) except in the case of the modifications by Howard Brenner and Reese et al., telling me that NASA is probably not accounting for hypersonic shockwaves since they can generate so much thrust with their truly awesome supply of LOX. Alternatively, maybe Max Q lets us know when we can kick up to hypersonic speeds, where shockwaves cannot be generated due to air density? Can anybody help me resolve this problem? Once again, it's just that it seems that NASA does not take into account hypersonic shockwaves, and I don't know why or how that's possible without them blowing up. Launch only, re-entry doesn't matter much to me at the moment. -- kanzure (talk) 16:13, 9 March 2008 (UTC)

Basically it's not a problem at all; rockets optimally leave the atmosphere very early on to minimise drag, and so the Shuttle doesn't go supersonic or even hypersonic until it has left the thick part of the atmosphere. You don't precisely get shockwaves if you're high enough because the molecules are too far apart. In any case there's nothing magical about hypersonic shockwaves, nothing blows up, you just get a strong heating effect; oh and the shockwaves are a slightly different shape than at Mach 2, but it's much of a muchness. Bottom line is that NASA doesn't have to care much- the main tank gets a bit toasty but the Shuttle laughs at it (since it's designed for reentry).- (User) WolfKeeper (Talk) 16:42, 9 March 2008 (UTC)

Reentry is a completely different ball of wax though, the air pressure is much higher, and the hypersonic shockwaves and the heating effects are intense. There's also a minor design screwup on the shape of the Shuttle, and it tends to be a bit unstable during reentry (the first Shuttle mission gave the crew some cause for concern). That's because the shockwaves apply pressure in a slightly different place on the vehicle than they would at lower speeds.- (User) WolfKeeper (Talk) 16:42, 9 March 2008 (UTC)

The Shuttle, as well as most if not all rockets, initially hold a very high AOA to escape the densest parts of the atmosphere as soon as possible. Once it is higher up, it pitches down to gain tangential velocity. As it approaches its final orbital velocity, it is high above the highest reaches of the atmosphere, hence there is no reason to worry about significant hypersonic effects. However, on re-entry, the Shuttle's deceleration is brought about by an atmospheric drag force, which means it must hit the atmosphere traveling at only a little less than its full orbital velocity. The OMS engines do not have nearly enough delta-V to slow it enough to enter the atmosphere at the same speed it had when it escaped it on takeoff.--Squeakywaffle (talk) 23:53, 17 November 2008 (UTC)

Is the Space Shuttle a launch vehicle or launch system?

Is the Space Shuttle a launch vehicle or a launch system? In other words, does the term 'Launch vehicle' define the whole Space Shuttle, including the external fuel tanks and rocket boosters, or does it just define the orbiter that is attached to the whole structure? And also when using the term 'Space Shuttle', does it refer to the whole launch system or just the orbiter? The term is quite confusing to use when describing the whole launch system and orbiter. WinterSpw (talk) 00:04, 2 April 2008 (UTC)

Hmm I think I found the answer to my own question. In the article 'List_of_launch_vehicles#United_States' under 'Space Shuttle', it says 'Space Shuttle Solid Rocket Booster', so the launch vehicle of the Space Shuttle is actually just the booster rockets. Neat. WinterSpw (talk) 00:11, 2 April 2008 (UTC)

• The Orbiter has rocket engines too. The integrated shuttle launches as a unit, so it is both. Launch system redirects to Launch vehicle now for whatever that's worth. -Fnlayson (talk) 14:02, 21 August 2008 (UTC)

phil alit

i am trying to find anyone who knew phil as an engineer with rockwell international space program doing the pitch and awe research in southern california around late 1960's to his 25 year retirement. he joined the orange county sheriffs dept and retired there too. any info or paperwork would be helpful regarding his burial in national cemetary. all info regarding his identy was lost in post office in yaccua valley, ca post office. we only got $100. for lost!!! your infor and paper work would help in final burial of him. thanks so much. vince alit, 360-658-3992 or vbalit1@yahoo.com. marysville, wa.71.113.0.127 (talk) 16:09, 2 April 2008 (UTC)

Why scrubs?

Does anyone know the origin of "scrubbed"? Why aren't the missions delayed, postponed or canceled? I've never heard of a concert being "scrubbed", but many have been canceled or postponed. 209.244.7.241 (talk) 03:03, 12 June 2008 (UTC)

Used as a verb, one of the standard meanings of "scrub" means to cancel an event. It's not unique to space missions. A concert or other event can be "scrubbed", and the word is sometimes used this way. See any dictionary. Joema (talk) 13:06, 12 June 2008 (UTC)

STS vs. Space Shuttle

Reading over various historical sources, the "Space Transportation System" originally refereed to a much grander set of vehicles. These included the Shuttle (then known as ILRV), an orbital tug, and a nuclear-powered inter-lunar/inter-planetary tug. One of the major mission profiles for the Shuttle would be up-n-down fuel delivery to an orbiting tank farm that would supply both of these tugs. When all of this got cancelled, NASA simply used STS to refer to the Shuttle only. Is this something worth mentioning here? Or perhaps it's own article? Maury (talk) 13:55, 21 August 2008 (UTC)

Chemistry spelling or local spelling on aerospace articles

See here where I have used this article as an example. Should the American nature of the subject take precedence over the chemical element guideline in cases like this when it comes to aluminium vs. aluminum? --John (talk) 06:09, 2 September 2008 (UTC)

I would suggest using whatever spelling NASA uses in its documents that mention the element. Ariel♥Gold 12:21, 2 September 2008 (UTC)

Better image of STS-125

This is a superior image to the one currently displayed in the article: Image:Space_shuttles_Atlantis_(STS-125)_and_Endeavour_(STS-400)_on_launch_pads.jpg. It should probably replace the other one and the caption should be rewritten since it's grammatically incorrect as it stands now. Cumulus Clouds (talk) 19:16, 5 October 2008 (UTC)

Image swapped out. I also rewrote the caption earlier in the day, so hopefully that should fix that, too. SchuminWeb (Talk) 04:32, 6 October 2008 (UTC)

Stop the stalking CC... — BQZip01 — ^talk 04:46, 6 October 2008 (UTC)

Convert

Hi everybody, I'd just like to let you all know that I've changed the unit values that were manually input with the {{convert}} template. EOZyo (мѕğ) 08:03, 12 May 2009 (UTC)

Make sure to specify US spelling (sp=us) where the units are spelled out. I fixed some, but may not have gotten all of them. -Fnlayson (talk) 14:18, 12 May 2009 (UTC)

I'm not sure what you did exactly. In this article, the "mass" of the shuttle is given in lb and t; I was taught in university that lb is a unit of force and the English unit of mass is the slug; it is not clear if t is English ton or metric tonne. Wouldn't it be better, at least in science-related articles, to use primarily SI? Olde English units might be added in parentheses, but my preference is to completely eliminate them? The sooner they are lost and forgotten, the better. I will not presume to undertake this monumental task on my own, and certainly not without a policy statement from someone in authority. Onerock (talk) 19:23, 13 May 2009 (UTC)

That's Pound (mass) (lb or lbm), not Pound-force (lbf). Both sets of units should be listed per MOS:CONVERSIONS. -Fnlayson (talk) 19:49, 13 May 2009 (UTC)

Post Mission activities???

This page has a very good description of launch / orbit / re-entry / landing procedures, but I have always wondered what happens to the shuttle after all that. I know it involves re-working the tiles, re-filling the srb's, getting a new ET and putting the whole thing together. If anyone in the know could write about the specifics I would be grateful and I think it would improve this article. —Preceding unsigned comment added by 69.120.182.253 (talk) 00:01, 13 May 2009 (UTC)

Slideshow?

I removed an external link to this Discovery Channel slideshow because, per WP:EL I do not see that it adds anything encyclopedic that the article would not contain if it was a featured article. Another user has restored the link. Is there a consensus here that the link should remain? --John (talk) 23:59, 15 May 2009 (UTC)

The slideshow contains info and images this article does not have now. If this article were upgraded to an FA then the link would probably not add much. That's what I think. Don't care to argue about keeping it though. -Fnlayson (talk) 03:23, 16 May 2009 (UTC)

"Events" versus "Remarks" in mission list...

I'm hoping to prevent an edit war with Fnlayson by providing a convincing argument why my edits are the proper ones. My goal is to get consensus.

The sentence before the mission list chart reads: "Below is a list of major events in the Space Shuttle orbiter fleet." Based on this statement, I see that each "notable" mission is listed, and the event for which the mission is notable is placed in the "Event" column. Additional notes, including the mission number appear in the "Remarks" column.

I came to this page and noticed that mission STS-107 had the event "Earth science research mission" which was puzzling, as no other entry lists the nature of the mission unless the mission was regarding an important payload or event. Cases in point: mission STS-92 has its event as "100th Space Shuttle mission", and mission STS-30 has its event as "The first Space Shuttle mission to launch a space probe, Magellan." These cases seem very logical to me, and the entry for STS-107 seems very illogical: there was nothing notable about the Earth science research mission, itself; what is notable is that the shuttle "Disintegrated on re-entry".

I made this change, removing "Earth science research mission" and replacing it with "Disintegrated on re-entry", so that the entry looks very similar to the entry for STS-51-L, with its event "Disintegrated 73 seconds after launch" and its remark "STS-51-L, all seven crew members perished."

Subsequently, Fnlayson replaced the "Earth science research mission" event and modified the remark from "STS-107, All seven crew members perished." to "STS-107, Disintegrated on re-entry and all seven crew members perished." with the edit summary: "not the same as Challenger, performed a mission on orbit".

My argument against this is two-fold:

1. as indicated above, the event for which the mission was notable should appear in the "Event" column, and
2. while it is true that the STS-51-L never got its chance to complete its mission and STS-107 did, the listing of a mission is impertinant, per se, as otherwise, missions such as STS-92 would list the mission purpose ("International Space Station assembly") in the "Event" column and the fact that it was the 100th mission in the "Remarks" column.

I hope you'll agree. —  X  S  G  09:32, 13 June 2009 (UTC)

I only added "Earth science research mission" back to the Columbia accident entry a couple times. Removing that seems to imply they did nothing on the mission. It's a different situation than the Challenger accident. In general major changes to articles ought to be mentioned on their talk pages beforehand. -Fnlayson (talk) 01:23, 18 June 2009 (UTC)

I'd like to add that for the same reasons, I question whether the Enterprise's October 12, 1977 flight is notable enough for inclusion in the list. It is the first mission with the tail-cone off; if this is the reason why the mission is notable then it belongs in the "Event" field, and otherwise, the entry isn't really worth mentioning. —  X  S  G  09:46, 13 June 2009 (UTC)

If no one has anything to say about this, I'll go ahead and make the change... —  X  S  G  01:01, 18 June 2009 (UTC)

Shuttle-Derived Heavy Lift Launch Vehicle Page Needs Work!

I have created the Wikipedia entry for the Shuttle-Derived Heavy Lift Launch Vehicle, but it needs someone to read the two articles and watch the NASA video and then write a decent Wikipedia article. Can someone please step forward and do this? Radical Mallard (talk) 23:58, 11 July 2009 (UTC)

shuttle cannot fly unmanned

"As the shuttle cannot fly unmanned, each of these improvements has been "tested" on operational flights"

Must be mistaken, unless you can provide verifiable citations .From what I understand the Shuttle is perfectly capable of launching to orbit and returning to earth totally under control of the on board computer. Viralmeme (talk) 14:39, 16 July 2009 (UTC)

It is widely known the shuttle cannot fly unmanned. That's why the first mission STS-1 had a crew, despite the great risk. Recently a new contingency capability was added to allow the orbiter to deorbit and land without a crew. This is called Remote Controlled Orbiter (RCO), and is only used if a manned orbiter reaches the ISS but is deemed unsafe for manned operation to return (e.g, orbiter is flyable but damaged). In that case the crew takes refuge in ISS, the RCO hardware is installed on the orbiter, and an unmanned return is attempted. The RCO consists of cables and software which automate tasks previously done by the crew. This includes deploying air data probes, landing gear and drag chute. http://www.nasaspaceflight.com/2006/06/rco-saving-a-crippled-discovery/

Weights

The gross lift off weights mentioned in the article cannot be correct: If the Space swhuttle it self has 110 tons, the external tank has 756 tons and the bossters have 590 tons eacht, the gross liftoff weight would be 2046 tons overall, not the mentioned 2000 tons. --MrBurns (talk) 21:05, 25 July 2009 (UTC)

Colors / paint

Article currently says: "At launch, it consists of a rust-colored external tank (ET), two white, slender Solid Rocket Boosters (SRBs), and the orbiter."
The ET was originally painted -- STS-1#External_tank:

"STS-1 was one of only two shuttle flights to have its External Tank (ET) painted white. In an effort to reduce the Shuttle's overall weight STS-3 and all subsequent missions used an unpainted tank, which translated into a weight savings of approximately 272 kg / 600 pounds. This lack of paint gives the ET its distinctive orange color now associated with the Space Shuttle."

-- 201.37.230.43 (talk) 20:24, 31 August 2009 (UTC)

OK, but NASA does not even agree on what color to call it. The NASA press release used above says "orange spray-on foam...". Another release I found says "rust-colored external tank". So I compromised and listed dark orange in the text. -Fnlayson (talk) 23:26, 31 August 2009 (UTC)

Main engine

What is the point of the main engine? The solid rocket boosters are lighter, smaller, and far more powerful; why not let them do a little more work and eliminate (or drastically cut the size of) the external fuel tank? I'm sure there's an answer, but I can't find it, and it should probably be mentioned. 138.78.102.167 (talk) 02:39, 22 September 2009 (UTC)

The Shuttle has 3 main engines. An SRB is not lighter and smaller than them. The SRBs act like a rocket stage. They separate after their fuel is expended so their remaining mass does not have to be carried. -Fnlayson (talk) 03:24, 22 September 2009 (UTC)

I apologize, I confused thrust with work. The SRBs provide more thrust; however, they have a shorter burn time. (When I said they were lighter and smaller, I was comparing them to the external fuel tank, which is true). I'm still unclear on the reason to incorporate both liquid and solid rockets into a launch (if they're burning simultaneously, they are under similar conditions, and one must perform better than the other), but I fear the answer may not be as simple as I had hoped. I'll still be interested in an answer if someone's willing to give it, and I'll try to incorporate it into the article. (No need to talk down to me; I have a decent physics background, despite the earlier mistake.) 138.78.102.167 (talk) 04:58, 22 September 2009 (UTC)

The shuttle is basically a tripropellant rocket.- (User) Wolfkeeper (Talk) 14:25, 22 September 2009 (UTC)

The exhaust speed of the main engines is much higher. When you're down low, the vehicle is heavy and you want a lot of thrust and exhaust speed is a bit less important. When you're up high, you want to run with a hydrogen engine because, including the fuel and oxidiser, that's lighter and makes the lower stage stuff smaller. The main engines give high exhaust speed, but relatively low thrust, the SRBs give lots of thrust but a low exhaust speed. They're also cheaper to build. If they ran solid rockets all the way to orbit, the takeoff weight would be several times higher, and you would probably need three stages of solid rockets because of the lower exhaust speed. If they ran main engines all the way to orbit the vehicle would be physically much bigger (including the necessary propellant) and more expensive.- (User) Wolfkeeper (Talk) 14:25, 22 September 2009 (UTC)

Is this mentioned in the article? If not, it'd make a great addition (with a citation). :-) Colds7ream (talk) 14:45, 22 September 2009 (UTC)

Space Shuttle/STS Segment/System

The first sentence is technically misleading. The STS is the system and includes a ground segment, a comm/orbital segment, and the Space Shuttle segment. The Space Shuttle segment includes the Orbiter element, SRB element, etc. I have modified appropriately with the word "part." HyperCapitalist (talk) 03:31, 2 October 2009 (UTC)

Regarding your subsequrnt edit, STS-61-A was West German-funded. I'm not sure how best to work this in, if at all. Leads generally don't need sources as long as the info is cited in the main text, but I haven't checked to see if it covers this. You should be able to find sufficient cites in the STS-61-A article if you need them. - BilCat (talk) 04:23, 2 October 2009 (UTC)

I fixed the referenced article -- _payload_ operations for the mission were largely run out of Germany. This is entirely different than Shuttle operations. HyperCapitalist (talk) 04:26, 2 October 2009 (UTC)

I saw your change to this article, and while I think it is misleading (I don't believe the payload is considered part of the STS), I'll leave it for someone else to modify. HyperCapitalist (talk) 04:34, 2 October 2009 (UTC)

• Good point Shuttle operations vs. payloads ops. I reworded it to "The United States funded STS development and shuttle operations." I think it'd take another sentence to cover the payload operations but that probably doesn't belong in the Lead. -Fnlayson (talk) 04:42, 2 October 2009 (UTC)

I think you could just say "STS development and operations" as the payload isn't part of the STS per http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts_overview.html. HyperCapitalist (talk) 04:45, 2 October 2009 (UTC)

Works for me! - BilCat (talk) 04:49, 2 October 2009 (UTC)

• Sure. I included shuttle so it'd be more clear and maybe prevent unneeded wording changes. -Fnlayson (talk) 04:52, 2 October 2009 (UTC)

Big mistake in the SRB specs

Space Shuttle Wikipedia page: "Empty weight (per booster): 63,272 kg (139,490 lb)"

SRB booster Wikipedia page: "The inert weight of each SRB is approximately 200,000 lb (91,000 kg)."

Astronautix SRB page: "Empty Mass: 86,183 kg (190,000 lb)." http://www.astronautix.com/stages/shulesrb.htm

NASA page about the SRB: "The inert weight of each SRB is approximately 192,000 pounds." http://spaceflight.nasa.gov/shuttle/reference/shutref/srb/srb.html

posted by gaetano marano Oct. 30, 2009 —Preceding unsigned comment added by 62.10.106.185 (talk) 22:27, 30 October 2009 (UTC)

Okay. Go ahead and make it so. It's okay to get your hands dirty and fix stuff. SchuminWeb (Talk) 23:21, 30 October 2009 (UTC)

the changes you've made aren't right... the exact data are in the NASA page linked above

- SRB weight approximately 1,300,000 pounds at launch

- propellant weight of the SRB approximately 1,100,000 pounds

- inert weight of the SRB approximately 192,000 pounds

- peak thrust (sea level) approximately 3,300,000 pounds at launch

posted by gaetano marano Oct. 31, 2009—Preceding unsigned comment added by 62.10.110.211 (talk) 04:00, 31 October 2009 (UTC)

The SRB data was corrected and cited. Note that there has been about 3 different weight SRB motor cases and the current one is the medium weight one. -Fnlayson (talk) 19:11, 31 October 2009 (UTC)

the SRBs can be changed on some points but NOT in their weight since they are made with the SAME rings built decades ago and reused several times

however, the most recent NASA page (and data) about the SRB is here: http://www.nasa.gov/returntoflight/system/system_SRB.html

so, the current SRB Stats are:

Thrust at lift-off: 2,650,000 pounds

Propellant Properties: 16% Atomized aluminum powder (fuel) 69.8% Ammonium perchlorate (oxidizer) .2% Iron oxide powder (catalyst) 12% Polybutadiene acrylic acid acrylonite (binder) 2% Epoxy curing agent

Weight Empty mass: 193,000 pounds

Propellant mass: 1,107,000 pounds

Gross lift-off mass: 1,300,000 pounds

please note that the SRB lift-off thrust is lower than the (3.3Mlbs) peak thrust since the SRB reach the peak about 20 seconds after lift-off

posted by gaetano marano Oct. 31, 2009 . —Preceding unsigned comment added by 84.221.31.194 (talk) 22:19, 31 October 2009 (UTC)

No need to repeat data. On the medium weight case, the walls are only 0.002-0.004 inches thinner than on the original heavy weight case. Propellant and other specific details really belong at Space Shuttle Solid Rocket Booster instead of this article. -Fnlayson (talk) 15:01, 1 November 2009 (UTC)

SRB thrust

The SRB sea-level liftoff thrust is about 2.8 million lbf (12.5 MN), as measured from actual flight data of STS-107 and published in the Columbia Accident Investigation Report. To my knowledge there is no flying "high performance" RSRM. There have been various proposals for upgraded SRMs such as the ASRM and Filiment-Wound SRB (FWSRB), however none actually flew. We must use consistent numbers throughout this and other related articles. It's confusing and inconsistent to state different thrust numbers for the same item.

The various thrust specs given by different references are typically non-specific: they don't state whether sea level or vacuum thrust, liftoff or peak thrust, momentary vs average thrust, etc. The highest reliability numbers are from actual measurement, and from STS-107 we have the SRB thrust graph, which is in Space Shuttle Solid Rocket Booster.

If there has somehow been an SRB performance upgrade since STS-107, before using it in any article we'll need an authoritative reference, including whether it's sea level vs vacuum thrust, average vs peak thrust, a specification vs a measured value, etc. Joema (talk) 12:56, 1 November 2009 (UTC)

I referenced the source for that (ref. 24). 3 Mlb is the thrust in a vacuum for the high-performance motor SRB used starting with STS-8. You need to reference the 2.8 Mlb value in that line since it is different. -Fnlayson (talk) 14:37, 1 November 2009 (UTC)

---

the data I give here don't come from "different references" but directly from the MOST "authoritative reference": NASA

so, the RIGHT specs for the SRB to put in the Space Shuttle (and in the SRB) page are:

Peak thrust: 3,300,000 pounds

Empty mass: 193,000 pounds (87,543 kg.)

Propellant mass: 1,107,000 pounds (502,127 kg.)

Gross lift-off mass: 1,300,000 pounds (589,670 kg.)

given the source (NASA) any further dispute about these data seems silly

posted by gaetano marano Nov. 1, 2009. —Preceding unsigned comment added by 62.10.102.8 (talk) 18:56, 1 November 2009 (UTC)

I hope that, at least, things like the "SRB mass" don't become a "religion's war"

the right data come from the N A S A websites, so, please change them in the article, without insist to leave your wrong data!

posted Nov. 7, 2009 by gaetano marano. —Preceding unsigned comment added by 62.10.107.72 (talk) 07:24, 7 November 2009 (UTC)

Did you even look at Reference 26?? That's a NASA report. -Fnlayson (talk) 15:21, 7 November 2009 (UTC)

yes, it's a 1990's document (but the content and the images look much older, from a pre-computer era...) while, the NASA link posted below, has been "Last Updated in March 5, 2006"

http://www.nasa.gov/returntoflight/system/system_SRB.html

posted by gaetano marano Nov. 7, 2009 —Preceding unsigned comment added by 84.220.206.66 (talk) 17:52, 7 November 2009 (UTC)

What significant changes to the SRB that would noticeably change its weight have been done since the post-Challenger accident redesign in late 1980s? That report gives exact numbers and has been checked/reviewed as part of it being released, while the web page probably has not been. (See peer review content at Wikipedia:Reliable sources#Scholarship.) Try signing your posts with 4 tildas (. ~~~~). -Fnlayson (talk) 04:34, 8 November 2009 (UTC)