You are not logged in.
...ATK would go out of its way to spread rumors...
no, of course... but these are "secrets" hundreds peoples (at NASA, etc.) knows, then...
But you also ignore the change in propellant, which affects the characteristics. Also since a significant portion of the boosters' dry mass is the end cap and nozzle throat, which won't be much heavier, then it doesn't need as much thrust.
infact I evaluate/indicate the dry mass increase around 22% of a standard SRB
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
But ultimately you don't know
You don't even know how much the performance of the booster, with any version of the booster, affects the payload of the rocket.
And please, "the rumors might be from real ATK/NASA/etc engineers!" ...and they might not. How do you know? At least as much weight should be given to the chance they are not, and thats assuming the rumors aren't lies.
22% huh? Where do you get that from? Adding an additional segment to the existing four-segment design but not making the end-cap or nozzle throat much bigger increases mass by a quarter? Thats fishy math.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...the rumors might be from...
I don't know where "rumors" come from, but (you know) they are MANY and (sometimes) TRUE
...22%...
this is my evaluation of the extra-weight for the 5th segment without the SRB cap... however, I'm not sure of that since the 1st/2nd interstage module may weigh MORE than an SRB's cap
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
Could the Ares VII perform Dr. Robert Zubrins four man, Mars Direct Mission with only two launches per landing?
I had to ask.
Offline
It would if it could be built. But frankly Ares VII is too heavy to be transported on the crawler, and would require significant pad modifications over Ares V.
I think Mars Direct originally called for a 130 tonnes to LEO booster, the same as the Saturn V, and the same as Ares V. With a higher-thrust upper stage, Ares V looks just like the original Ares.
However, the question is then whether Zubrins mass estimates will work, and many think they won't.
Personally, I would prefer something in the 160 tonne range. But it looks as though Ares V might be the biggest you could get away with at KSC.
- Mike, Member of the [b][url=http://cleanslate.editboard.com]Clean Slate Society[/url][/b]
Offline
...the rumors might be from...
I don't know where "rumors" come from, but (you know) they are MANY and (sometimes) TRUE
...22%...
this is my evaluation of the extra-weight for the 5th segment without the SRB cap... however, I'm not sure of that since the 1st/2nd interstage module may weigh MORE than an SRB's cap
.
Oh but you don't know
And the interstage doesn't have to resist the leading edge compression of hgih supersonic flight.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...22%...
this is my evaluation of the extra-weight for the 5th segment without the SRB cap... however, I'm not sure of that since the 1st/2nd interstage module may weigh MORE than an SRB's cap
.
Please show your mass assumptions for the various components then we will be able to assess your calculation. Thank you in advance.
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
Offline
...22%...
this is my evaluation of the extra-weight for the 5th segment without the SRB cap... however, I'm not sure of that since the 1st/2nd interstage module may weigh MORE than an SRB's cap
.Please show your mass assumptions for the various components then we will be able to assess your calculation. Thank you in advance.
AND if you are going to try and calculate payload, show your reasoning and calculations. Not just "oh but the rumors might actually be from anonymous NASA engineers who might not be lying(!!!)"
Plus, the end cap is not the nose cone: the end cap is a thick steel disk on the top end of the booster that prevents the hot high pressure gasses from escaping. The nose cone sits on top of this.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...you don't know...
when a news goes to the press EVERYONE can know it
...the interstage doesn't have to resist...[.../quote]
we are not talking of its resistence to compression, but of its MASS (that does the FULL flight of the SRB) ...the interstange mass is unknown now, but I feel it will be much more than the top of the SRB weight
.[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
Please show your mass assumptions for the various components then we will be able to assess your calculation. Thank you in advance.
...show your reasoning and calculations...
back to elementary school, teachers!
ok...
according to Astronautix [ www.astronautix.com/engines/srb.htm ] the SRB data are:
standard SRB gross mass: 589,670 kg.
standard SRB empty mass: 86,183 kg.
then, the total SRB solid propellent mass is: 503,487 kg.
and the SRB segment propellent mass is: 125, 871 kg.
if we add (only) the 5th segment propellent mass, we have: 715, 541 kg.
we must add the dry mass weight of one SRB segment ...unfortunately, I've not found a source for the exact weight ...then, I've assumed a weight around 9 mT: SRB dry mass, less 12 mT for the (scrapped) recovery system, less 2-4 mT for the top parts of the standard SRB (not used with the Ares-I) less 2/7th of weight for the down parts/nozzle/TVC/etc. of the SRB
so, the 5-seg.SRB GLOW will be in the 724.5 mT range ...that is (around) +22.8% of the standard SRB mass... a little MORE than my previous evaluation, NOT less... and it is a further mass the new SRB must lift! ...also, we must ADD (when we will know it) the interstage mass!
think that, if the newSRB's (5th seg. + interstage) extra-mass wil be too much, the REAL increase of payload (vs. the standard SRB) may result RIDICULOUS ...especially if compared with the (3+ years) R&D time and ($3 billion) R&D costs the newSRB will need....... :cry:
then, if the 5th segment will (substantially) lift (only) ITSELF (and a small amount of tons that, great part, is NOT extra-payload, but only 2nd stage mass...) WHY do they spend so much time and money to have (substantially) NOTHING ???
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
.
thanks to the cIclops' link [ http://images.spaceref.com/news/2007/20 … 5.esmd.pdf ] now we know that the Ares-I 5-seg.SRB 1st stage will weigh 906,068 kg. !!! ...in other words... it has only FIVE segments, but its weight will be like a 6.5-segments SRB !!!
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
thanks to the cIclops' link [ http://images.spaceref.com/news/2007/20 … 5.esmd.pdf ] now we know that the Ares-I 5-seg.SRB 1st stage will weigh 906,068 kg. !!! ...in other words... it has only FIVE segments, but its weight will be like a 6.5-segments SRB !!!
Nope. Currently Ares I total weight is 907 mT.
Checkout the excellent summary from Ed Kyle - the RSRB GLOW is 734 mT containing 630 mT of PBAN propellant.
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
Offline
the RSRB GLOW is 734 mT containing 630 mT of PBAN propellant.
:oops: ...you're right... my mistake... (due to a "not so clear" NASA specs or to my "not so good" english...)
however... the 734 mT figure is very close to my "standard SRB + 20%" 5-seg.SRB weight evaluation published six months ago in the Aug. 12, 2006 update of my SRB article [ http://www.gaetanomarano.it/articles/011srb5.html ] and (in the same days) on some space forums and blogs (or the most recent 22% evaluation published here)
the real figure is SRB+24% but it includes the 1st/2nd stages interstage module that is FIRMLY joined with the 5-seg.SRB (and jettisoned with it)
(probably) without the interstage mass the 5-seg.SRB weight will perfectly match my SRB+20% evaluation!
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
Haha! You have no proof of any kind how that the SRB will perform or how it will affect the payload of the rocket.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...how that the SRB will perform...
apparently very poor... less than 173 mT (2nd stage, Orion, etc.)
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
...how that the SRB will perform...
apparently very poor... less than 173 mT (2nd stage, Orion, etc.).
But you don't know
And don't forget the J-2X is much more efficient and powerful than J-2S.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...how that the SRB will perform...
apparently very poor... less than 173 mT (2nd stage, Orion, etc.).
But you don't know
everyone can know it doing a simple math operation from NASA specs
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
apparently very poor... less than 173 mT (2nd stage, Orion, etc.).
But you don't know
everyone can know it doing a simple math operation from NASA specs
.
No you can't, because the performance of the new SRB fuel, new improved J-2, and several other factors (escape tower, actual mass of SRB components, etc) which also influence the payload.
You don't know
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
No you can't, because the performance of the new SRB fuel, new improved J-2, and several other factors (escape tower, actual mass of SRB components, etc) which also influence the payload. You don't know
NO ONE (not even NASA) knows (now) these details ...they have just set a target and in the next years they must work to reach the planned specs
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
No you can't, because the performance of the new SRB fuel, new improved J-2, and several other factors (escape tower, actual mass of SRB components, etc) which also influence the payload. You don't know
NO ONE (not even NASA) knows (now) these details ...they have just set a target and in the next years they must work to reach the planned specs
.
Then you can't comment about how the rocket is insufficient, and failing to meet these goals.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...you can't comment about how the rocket is insufficient...
the (latest weeks) rumors about an "unpowered Ares-I" don't come from me (and NASA admits the J-2x needs more power to meet the Ares-I specs)
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
Then that is all they are, rumor, speculation, and possibly lies.
Of course the J-2X needs more thrust, that was planned for already.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
Offline
...you can't comment about how the rocket is insufficient...
the (latest weeks) rumors about an "unpowered Ares-I" don't come from me (and NASA admits the J-2x needs more power to meet the Ares-I specs)
.
Oh not again! Griffin, Horowitz, Hanley, Cook and Doug Stanley have all responded with details and numbers to these destructive baseless rumors. Engineers are working hard to complete the specification and design, let them finish the job before making criticisms. Why keep undermining this project? Bad opinions have a way of spreading far and wide, repeated and exaggerated. NASA has enough money problems already with the continuing resolution and returning shuttle to flight, this type of negative NASA bashing won't help. If Constellation is cancelled, say goodbye to US human spaceflight for a long long time, or is that the idea?
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
Offline
...rumors...
sometimes "rumors" are true (and that happens many times in every field) ...well, if we talk of TO-DAY specs (with a too heavy Orion and an underpowered J-2x) the rumors about an "underpowered" Ares-I are (clearly) TRUE ...of course, all problem may be solved in future, but TO-DAY that problems actually exist
...If Constellation is cancelled, say goodbye to US human spaceflight...
I doubt that some critics on space forums can "cancell the ESAS plan"!!! ...it risk to be cancelled only if the new vehicles will not work
.
[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]
Offline
...rumors...
sometimes "rumors" are true (and that happens many times in every field) ...well, if we talk of TO-DAY specs (with a too heavy Orion and an underpowered J-2x) the rumors about an "underpowered" Ares-I are (clearly) TRUE ...of course, all problem may be solved in future, but TO-DAY that problems actually exist
...If Constellation is cancelled, say goodbye to US human spaceflight...
I doubt that some critics on space forums can "cancell the ESAS plan"!!! ...it risk to be cancelled only if the new vehicles will not work
.
Yes sometimes. But there is no evidence that Ares I is underpowered, on the contrary it seems to be fine. Space forum critics can't cancel the project, but others even less knowledgeable read what they say and believe it. And so the rumors spread. Lies are so easy to makeup and so hard to counter. IIRC a congressman said recently that the project had problems and his source was "the internet"
The engineering is still very early, there is no way you can talk definitively about the final performance of a new vehicle without access to all the internal numbers and details. And even then, reality always has something to say when it flies. It's easy to be skeptical, but just being skeptical is not enough. NASA have produced lots of numbers and details, they look fine. What are these rumors based on? Oh this is such a waste of time. Put up or shut up.
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
Offline