>>> The Ares-1 can't fly >>>

gaetanomarano · 2007-11-04 09:17:26

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The latest specs (below in this post) shows that the Ares-1 can't fly since it has NOT enough thrust to lift the SRB's 5th segment "extra-mass" as explained in my new article:

http://www.ghostnasa.com/posts/012arescantfly.html

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cIclops · 2007-11-04 10:06:43

The latest specs (below in this post) shows that the Ares-1 can't fly since it has NOT enough thrust to lift the SRB's 5th segment

Eh? the baseline configuraiton shows the GLOW (Gross Lift Off Weight) as 2,036,356 lbm and the first stage thrust is 3,510,791 lbf, that's a Thrust to Weight ratio of 1.72. Plenty of power!

gaetanomarano · 2007-11-04 10:26:18

The latest specs (below in this post) shows that the Ares-1 can't fly since it has NOT enough thrust to lift the SRB's 5th segment
Eh? the baseline configuraiton shows the GLOW (Gross Lift Off Weight) as 2,036,356 lbm and the first stage thrust is 3,510,791 lbf, that's a Thrust to Weight ratio of 1.72. Plenty of power!

if that's true, then the Shuttles has flown 30 years with +50% overpowered SRBs and the max upperstages' mass calculations of the early CLVs was wrong (since my evaluations starts from both specs)

unfortunately, my evaluations (simply) confirms several months of rumors about an "underpowered Ares-1"

also, if the 5-seg.SRB really give "plenty of power" and the 4-seg. version give "enough power" why do spend over $3 billion to develop an "overpowered" SRB ?

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cIclops · 2007-11-04 11:01:32

unfortunately, my evaluations (simply) confirms several months of rumors about an "underpowered Ares-1"
also, if the 5-seg.SRB really give "plenty of power" and the 4-seg. version give "enough power" why do spend over $3 billion to develop an "overpowered" SRB ?

Look at the Gross payload and Constellation CARD requirements, there are reserves for both the Exploration mission (17%) and the ISS mission (8%), Ares I meet its requirements with margin!

The 5 Segment SRB is costing $1.8 billion to develop ... see the ATK contract details here

There is a big advantage in using the 5 Segment SRB as it will be common with Ares V and therefore reduces the Constellation system development and operational costs.

gaetanomarano · 2007-11-04 11:53:56

Look at the Gross payload and Constellation CARD requirements, there are reserves for both the Exploration mission (17%) and the ISS mission (8%), Ares I meet its requirements with margin!

both drawings of my article come from original NASA documents

the first (original) NASA drawing/document says us that a 4-segments SRB can lift only 182 mT of TOTAL upperstages' mass to the 55 km. SRB separation altitude

since it was "not enough" NASA has shifted to the 5-segments SRB that another (original) NASA drawing/document says us can lift only 192 mT of US' mass

but the 5-segments SRB don't give that extra-thrust for free, since it has a 145.5 mT of "extra-mass" to lift (the 5th segment)

well, the question is: "who lift these 145.5 mT of extra-mass?"

The 5 Segment SRB is costing $1.8 billion to develop

this is only the most recent part of the money that NASA has paid (or will pay) to ATK for the new SRB and (IIRC) includes ONLY the R&D and three TEST motors

There is a big advantage in using the 5 Segment SRB as it will be common with Ares V and therefore reduces the Constellation system development and operational costs.

there are NO advantages but ONLY giant costs and longer timeline to fly

as explained in my "Super SLV" article, NASA can use three standard SRB (to, also, cover the 13 mT lack of payload of the current AresV design)

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RedStreak · 2007-11-04 11:58:49

Oh great, more anti-Constellation raving.

Although I'm sure you crunch numbers well gaetanomarano and can draw/tweak a few jpeg images it sounds more like a publicity stunt for your site.

I think I'll trust Cyclops' comments as well as actual press releases.

Sorry to attack but I just get annoyed hearing space enthusiasts talk like they are in charge of NASA; unless you have an engineering degree and a job within the space industries all most enthusiasts can do is rant on the sides, or more productively write a few letters to congressmen or organizations like the Planetary Society.

Continue posting your ideas and opinions gaetanomarano, but for the love of Pete do it with a grain of salt - I consider Constellation as a blessing NASA's been overdue for. Was it better back in the lull of the STS aka Challenger days?

That and post your Ares stuff in the actual Ares I (or V) threads.

gaetanomarano · 2007-11-04 12:11:00

Oh great, more anti-Constellation raving.

no, it's false, since I do critics, but, also, write/post solutions and alternatives

...you crunch numbers well...

don't forget that my "crunched" numbers start from true NASA data

I think I'll trust Cyclops' comments as well as actual press releases.

the latest Ares-I specs come from a cIclops' post

...unless you have an engineering degree...

there is no need of an engineering degree to do so basic calculations...

...write a few letters to congressmen...

I believe that Space forums and blogs are the right place to talk of Space (if not, what else?)

...do it with a grain of salt...

I put so much "grain of salt" in my articles and posts to actually see (or see months before) things others will see very much later... maybe, after reading my articles...

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Austin Stanley · 2007-11-04 14:31:05

I hate to start of with an 'appeal to authority' argument, but it seems the most logical one to start with. The engineers at NASA are fairly smart guys. They have managed to design quite a few successful spacecraft so far. So it seems to me that they would notice such glaring design discrepancies like the Ares I not having enough thrust to lift itself of the ground.

Indeed the image you post clearly shows that the vehicles Gross Lift Of Weight (GLOW) is considerably less then the thrust of the first stage. Why on Earth would NASA fabricate these documents if it were not so?

Clearly the most likely solution to this dilemma is that your calculations showing that the 5 Segment SRB is not powerful enough are in error someplace.

gaetanomarano · 2007-11-04 16:15:52

I hate to start of with an 'appeal to authority' argument, but it seems the most logical one to start with. The engineers at NASA are fairly smart guys. They have managed to design quite a few successful spacecraft so far. So it seems to me that they would notice such glaring design discrepancies like the Ares I not having enough thrust to lift itself of the ground.
Indeed the image you post clearly shows that the vehicles Gross Lift Of Weight (GLOW) is considerably less then the thrust of the first stage. Why on Earth would NASA fabricate these documents if it were not so?
Clearly the most likely solution to this dilemma is that your calculations showing that the 5 Segment SRB is not powerful enough are in error someplace.

you're right, but the "discrepancy" exists and starts from orginal NASA data and documents

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gaetanomarano · 2007-11-05 05:04:13

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the 5-seg.SRB's 3.5 Mlbs. is the PEAK thrust that is available a few seconds after lift-off and for about 15 seconds, then, the SRB thrust falls, falls, falls, falls to half and less within the 123 seconds of the SRB burning (see the graph below about the shuttle-SRB thrust curve) so, the SRB "peak" thrust is a good figure to do a comparison, but NOT to know how much tons the new SRB can lift to 55+ km. of altitude

that's why the early CLV upperstages' mass (calculated by NASA engineers!) was ONLY 182 mT MAX and NOT "250", "300" mT or more (as the 3.3 Mlbs. peak thrust of the standard SRB could suggest...)

a solid propellent motor can't give a constant thrust (to lift more upperstages' mass) because it's thrust figure/curve depends ONLY from the propellent's internal shape (that, in a shuttle-SRB is an 11-points' star)

infact, each shuttle-SRB can lift itself and ONLY 240 mT of (shuttle, ET, payload) mass to 45 km. of altitude

do you know why the Shuttle flys?

it flys thanks to its three SSME that can "throttle" between 67% and "109%" ...these engines starts at 104% the power at lift-off then "throttle down" in the first seconds after lift-off to compensate the high SRB thrust and to keep the acceleration to 3G max, so, when the SRB thrust falls, they "throttle up" again to lift the Shuttle to LEO, that, also, thanks to the SSME vacuum thrust that reaches over 512 klbf. (while the sea level thrust is only 408 klbf)

if you start from the REAL figures of the max upperstages' mass of both (4-seg. and 5-seg.) motors (that NASA give in its OFFICIAL documents) you'll discover that a 5-segments SRB can't lift (both) 192 mT of upperstages' mass AND the 5th segment's "extra-mass" to 55+ km. of altitude

that since the Ares-1 has no "throttleable" SSME in the 1st stage... about this point, I doubt the astronauts can survive the lift-off since the (uncontrollable) SRB thrust in the 10-15 seconds after lift-off could give a LAS-like 10G+ acceleration...

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SpaceNut · 2007-11-05 09:21:51

This document contains the data for a real 5 segment SRB see page 7.

The data graph you indicate is for the current shuttle 4 segment and even when a 5th segment is added it gets another million pounds of thrust.

The newer 5 segment will have a wider nozzle, fuel grain geometry as well as faster burning type was being tried and will as the chart shows get even more thrust than the trial (fake 5 segment) unit.

Lets not forget that it is the initial push that is required to get the rocket moving and that as the fuel burns the rocket is getting lighter, atmospheric pressure is decreasing as well as the forces for gravity which will allow the rocket to do what is needed.

http://www.ae.gatech.edu/labs/ssdl/Pape … 202006.pdf

gaetanomarano · 2007-11-05 09:56:36

This document contains the data for a real 5 segment SRB...

there are NO REAL DATA about the 5-segments SRB because this new booster doesn't exist since it will be ready for tests in 2011

the ONLY real test of a 5-segments SRB (with small changes of the nozzle) was made by ATK in 2003 and has shown a mere +10% increase of thrust

here I post the most accurate data I have about the 5-segments SRB (that confirms my evaluations)

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gaetanomarano · 2007-11-07 08:44:07

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this (nov. 7) F.I. article CONFIRMS that the Ares-1 has problems to fly:

http://www.flightglobal.com/articles/20 … ncher.html

as predicted/evaluated in my (nov. 4) ghostNASA article:

http://www.ghostnasa.com/posts/012arescantfly.html

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SpaceNut · 2007-11-07 08:47:49

More of the rumors that are havingNASA admits "significant threats to performance" of Ares I launcher as posted in the article as being from "internal circular" that there are "significant threats" to the performance. With the "preliminary design review for the CLV first stage has slipped by up to six months".

five segments. Initially intended to be largely unchanged from the RSRM, its insulation, throat diameter, propellant chemistry and geometry, and number of segments had all been changed by December 2006. NASA sources also say that, due to ascent stresses, areas of the segment casing are to be modified for strengthening.

These are all things we here knew...

the agency's November internal circular says: "There are significant threats to the performance to be worked as the project works towards [PDR]."
The PDR delay is referenced in a report by CLV first-stage office deputy manager Thomas Williams. While unavailable for comment, Williams says in the report: "First-stage element analysis [ending January 2008 leads to] PDR data drop 16 February, [followed by first-stage] PDR on the 20th. [The design analysis cycle] DAC-2 element data drop is 1 April, [then] PDR data drop is on 15 May, [followed by full vehicle] PDR 22 July [2008]."

So why the delay?

gaetanomarano · 2007-11-07 08:59:32

So why the delay?

"problems, I suppose..."

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cIclops · 2007-11-07 09:17:51

the 5-seg.SRB's 3.5 Mlbs. is the PEAK thrust that is available a few seconds after lift-off and for about 15 seconds, then, the SRB thrust falls, falls, falls, falls to half and less within the 123 seconds of the SRB burning (see the graph below about the shuttle-SRB thrust curve) so, the SRB "peak" thrust is a good figure to do a comparison, but NOT to know how much tons the new SRB can lift to 55+ km. of altitude

As the RSRB burns it loses mass very quickly ... a LOT of mass, about 626 tons according to the baseline configuration details. This is basic rocket science, but calculating the exact payload is very complicated. Is it likely that ATK & NASA have made such a simple miscalculation? No.

(BTW gaetanomarano, you are doing exactly what you criticized NASA for, mixing metric and imperial units)

gaetanomarano · 2007-11-07 11:40:15

As the RSRB burns it loses mass very quickly ... a LOT of mass, about 626 tons according to the baseline configuration details. This is basic rocket science, but calculating the exact payload is very complicated. Is it likely that ATK & NASA have made such a simple miscalculation? No.

NASA don't say us everything, so, we can calculate the AVERAGE propellent use but not the REAL amount at each second of burn that is not linear since (both) thrust and propellent use depend from the propellent 11-stars shape

probably, the problem is that both SRBs have one or more points of burning with too much weight vs. the power in the same points

that's why the Ares-1 needs a 3.5 Mlbs. motor despite a liquid engine can lift the same payload with only 2-2.5 Mlbs. of 1st stage engines' thrust

(BTW gaetanomarano, you are doing exactly what you criticized NASA for, mixing metric and imperial units)

you're right, but, it's the mix of metric and imperial used by NASA, forums, wiki, astronautix, blogs, etc. that produce this confusion... ...when (first) NASA and all others will use ONLY the metric units, the confusion will end...

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cIclops · 2007-11-07 13:53:45

that's why the Ares-1 needs a 3.5 Mlbs. motor despite a liquid engine can lift the same payload with only 2-2.5 Mlbs. of 1st stage engines' thrust

Thrust is important, it has to be sufficient to counter the gravity loses and accelerate the vehicle (but not too much) to the required velocity. Ares I has a 17% reserve for lifting its required exploration payload to orbit, it's an elegant solution. The most powerful liquid engine available is probably the RS-68 with 663 klbf, so more than 3 would be needed to produce 2.5 Mlbf.

gaetanomarano · 2007-11-11 21:27:42

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I've added FOUR updates to my Ares-1 article with some NEW calculations that (clearly) show WHY the new Ares-1 can't fly:

http://www.ghostnasa.com/posts/012arescantfly.html

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RedStreak · 2007-11-14 11:43:41

Add THIS to your calculations:

http://www.energy-daily.com/reports/New … d_999.html

There's talk of a new method of storing hydrogen, and it sounds like it'd have great implications for space flight.

gaetanomarano · 2007-11-14 12:20:51

There's talk of a new method of storing hydrogen, and it sounds like it'd have great implications for space flight.

the article talks of "materials" that "absorb hydrogen up to 14 percent by weight at room temperature"

in other words, the "material" that "absorb hydrogen" (the tank of a rocket or a car) is SIX TIMES BIGGER and HEAVIER than the absorbed hydrogen

that could be useful for cars, but not for rockets

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RedStreak · 2007-11-14 17:08:38

Don't hold your breath over it; rockets use the stuff ALOT more than cars so guess where demand will be? 8)

cIclops · 2007-11-14 17:11:38

Hey gaetanomarano I agree with you!

Yep, 14% by weight at room temperature would be useful for fuel cells or maybe ground vehicles, but hopeless for spacecraft. IIRC a cryogenic LH2 tank is 95% or more fuel by weight.

gaetanomarano · 2007-11-17 11:57:11

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just added FOUR new UPDATES to my "Ares-1 can't fly" article:

http://www.ghostnasa.com/posts/012arescantfly.html

- latest news about a possible Ares-1 (dangerous) oscillation problem and the first manned Orion launch slip to June 2016

- old (but largely unknow) NASA press release about a possible in-flight stability problem (that must be solved)

- the lack of "safe lift-off abort mode" for (both) the 4-segments and the 5-segments SRB Ares-1 1st stage

- read why ALSO the Ares-5 can't fly (especially with the heavier 5-segments SRBs) nor leave the launch pad

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gaetanomarano · 2007-11-23 20:15:17

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I've UPDATED my "Ares-1 can't fly" article...

http://www.ghostnasa.com/posts/012arescantfly.html

...with an interesting thing found on the web:

Two years ago, when I've FIRST remarked on a Space forum the problem of the lack of a "safe lift-off abort mode" in the upcoming Ares-1, I was (literally) submerged by lots of critics and insults, but, now, surfing the web, I've found and SAVED (a "disliked" web page can disappear overnight...) a very interesting June 12, 1997 Boeing's News Release titled "Boeing To Study Liquid Fly Back Shuttle Boosters For NASA"...

http://www.boeing.com/news/releases/199 … 70612.html

...where the Boeing LFBB Program Director Ira Victer said that... "LFBB will use liquid propellants and will be fully throttleable and capable of safe shutdown. SRBs, which use a solid propellant, cannot be turned off once ignited... "The result is a booster system [the LFBB] more tolerant of engine failure and less likely to require mission aborts," Victer said. "In addition, hazardous booster operations in NASA Kennedy Space Center (KSC) Vehicle Assembly Building are eliminated, since LFBB fueling operations would occur on the launch pad, much the way the Shuttle's external tank is loaded today".

Then, in this ten-years-old document, BOEING (clearly) seems agree with me...

However, I'm not against the SRBs used as 1st stage of a rocket for manned launches... my only concern is that, this solution, needs many safety, structure and acceleration tests made NOW (not in 2009+) then, BEFORE any "final decision" about the Ares-1.

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