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The Ares-1 can't fly
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
Klaus Schmidt wrote: ...first of all your numbers are old... no, the specs in my first post are he most recent (look at the latest Orion shape atop the rocket) released a few days ago Quote: ...assume that the 4 segment booster wouldn't have any reserves for this task... no, read again my article, I think that only the the 4-seg. SRB can lift a resized Orion, since it has enough power without the 145.5 mT of extra-weight Quote: The only thing that was basically under discussion the last year or so was if the Ares I can launch the then still overweighted Orion into the proper orbit. if the Ares-1 has so much "power" that whole discussion (about an "overweighted Orion") would never exist... . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
campbelp2002 wrote: ...bad analogy... it's only an example... but it's also a bad analogy since the SRB has no wings nor the atmosphere to lift itself Quote: It is not ONLY the weight increase of the SRB that counts. It is the weight increase of THE ENTIRE VEHICLE that counts. you're right, but the "upperstages' mass saving" is in the range of 35.5 mT (182 x 1.25 - 192) that is always too small compared with the 145.5 mT extra weight of the new SRB, also, the low upperstages' mass is mainly due to the J-2X that has 40% less vacuum thrust vs. the SSME Quote: ...it STILL LIFTS OFF... just look and compare the 4-seg. and 5-seg. SRB curves in the blue graph posted here... in the first 40 seconds both thrust curves are very close... but the yellow curve refers to a booster that has 145.5 mT extra-weight and must lift 10 mT extra payload... Quote: ...it will BURN LONGER... no, it's official from the early specs released by ATK and NASA, the new SRB will burns ONLY a mere five seconds more than the old SRB that's since the solid propellent burns from the center of the motor to the external case the rocket will (or should...) reach 55 km. of altitude (10 km. more than the Shuttles' SRBs) since the acceleration of the new rocket will be 3.75G rather than the 3G max of the Shuttle . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
xiphius wrote: The shuttle leaves the launch pad because the thrust exceeds the weight. that's true in the first few seconds of peak thrust, then the SRB thrust falls and the SSMEs' thrust reach their max vacuum value of over 1.5 Mlbs. total . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Space Walker ![]()
Joined: Sun Jul 29, 2007 5:18 pm
Posts: 124 Location: UK |
According to the graph you posted earlier, not only does the thrust of Ares-I exceed its gross take-off weight, it does so for nearly FULL TWO MINUTES, while all the time getting lighter as it burns. It will get off the pad, it will obviously get off the pad, and your assertion that it won't is obviously wrong.
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
xiphius wrote: According to the graph you posted earlier, not only does the thrust of Ares-I exceed its gross take-off weight, it does so for nearly FULL TWO MINUTES, while all the time getting lighter as it burns. It will get off the pad, it will obviously get off the pad, and your assertion that it won't is obviously wrong. if you are right, then, you should answer three simple questions: 1. why have they shifted to a 5-seg.SRB if the old SRB has enough power (since it's curve is close to the new SRB) to lift the Orion? 2. if the new SRB has so much power, why are they cutting every kg. they can from the Orion? 3. if the new SRB is so powerful, why have they (resized) the 5.5 m. CEV to 5 m. only? the Ares 1-X launch will be not a real test, but could be only a fake, since they can just put the right (low) upperstage mass to have a lift-off... last... don't forget that all rumors about an "underpowered Ares-1" don't come from me (and CAN'T be due ONLY to a small Orion's extra-weight...) . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . Last edited by gaetanomarano on Tue Nov 06, 2007 1:05 pm, edited 1 time in total. |
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Space Walker ![]()
Joined: Sun Jul 29, 2007 5:18 pm
Posts: 124 Location: UK |
No, you are the one that claimed it could not leave the pad, so you should be answering the question "As its thrust greatly exceeds its launch weight for nearly the first two minutes, why do you think it can't lift off?" You made the claim, you defend it, instead of shifting your argument to one of overall performance.
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
xiphius wrote: No, you are the one that claimed it could not leave the pad, so you should be answering the question "As its thrust greatly exceeds its launch weight for nearly the first two minutes, why do you think it can't lift off?" You made the claim, you defend it, instead of shifting your argument to one of overall performance. if that is true there is no reason to adopt the new SRB since the old booster has very similar specs (but NASA has shifted to it) also, the peak thust is available about 10 seconds after lift-off my proposal is (simply) to go back to the standard SRB that has enough power without the 145.5 mT extra-weight that after a standard SRB test launch with the right payload to gather the true acceleration data in the full 123 seconds flight about the "Ares 1 problems"... just do a Google search with these keywords... you'll find 1,950,000 pages... however, I wait you answer MY questions too... . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . Last edited by gaetanomarano on Tue Nov 06, 2007 2:07 pm, edited 1 time in total. |
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
.
off-topic but interesting... this is the first image of the Orion's mockup made for tests:
well... it looks very much like MY "sliced Orion": http://www.gaetanomarano.it/articles/031easyways.html just look at the (small) distance between the door and the capsule top line... . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Moon Mission Member ![]() ![]()
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361 Location: Austin, Texas |
gaetanomarano wrote: just look and compare the 4-seg. and 5-seg. SRB curves in the blue graph posted here... T ------4 seg. ----- 5 seg ---- % diff. 0 --- 3,200,000 - 3,500,000 - 9.3% 10 -- 3,300,000 - 3,500,000 - 6.1% 20 -- 3,400,000 - 3,500,000 - 2.9% 30 -- 2,800,000 - 3,100,000 - 10.7% 40 -- 2,600,000 - 2,900,000 - 11.5% 50 -- 2,400,000 - 3,000,000 - 25.0% 60 -- 2,500,000 - 3,100,000 - 24.0% 70 -- 2,600,000 - 3,300,000 - 26.9% 80 -- 2,500,000 - 3,300,000 - 32.0% 90 -- 2,250,000 - 3,000,000 - 33.3% 100 - 1,900,000 - 2,600,000 - 36.8% 110 - 1,100,000 - 2,300,000 - 109.1% 4 seg. starting to shut down 120 ----- 10,000 - 1,950,000 - 4 seg. shutting down, 5 seg. about to shut down. 130 ----------- 0 ----- 25,000 - 4 seg. completely shut down, 5 seg. shutting down At launch the thrust difference is small as you say. At T+20 seconds it is even smaller. At T+30 the % difference is greater that at launch. At T+50 it goes to 25% higher and stays up for remainder of the Burn. And the 5 segment burn does not last only 5 seconds longer as you claimed; it lasts about 15 seconds longer. Basically, if ISP is unchanged and 25% more propellant is added, the total impulse goes up 25%. And that 25% extra total impulse has to lift only 20% more mass. |
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
Posts: 363 Location: Italy |
campbelp2002 wrote: gaetanomarano wrote: just look and compare the 4-seg. and 5-seg. SRB curves in the blue graph posted here... T ------4 seg. ----- 5 seg ---- % diff. 0 --- 3,200,000 - 3,500,000 - 9.3% 10 -- 3,300,000 - 3,500,000 - 6.1% 20 -- 3,400,000 - 3,500,000 - 2.9% 30 -- 2,800,000 - 3,100,000 - 10.7% 40 -- 2,600,000 - 2,900,000 - 11.5% 50 -- 2,400,000 - 3,000,000 - 25.0% 60 -- 2,500,000 - 3,100,000 - 24.0% 70 -- 2,600,000 - 3,300,000 - 26.9% 80 -- 2,500,000 - 3,300,000 - 32.0% 90 -- 2,250,000 - 3,000,000 - 33.3% 100 - 1,900,000 - 2,600,000 - 36.8% 110 - 1,100,000 - 2,300,000 - 109.1% 4 seg. starting to shut down 120 ----- 10,000 - 1,950,000 - 4 seg. shutting down, 5 seg. about to shut down. 130 ----------- 0 ----- 25,000 - 4 seg. completely shut down, 5 seg. shutting down At launch the thrust difference is small as you say. At T+20 seconds it is even smaller. At T+30 the % difference is greater that at launch. At T+50 it goes to 25% higher and stays up for remainder of the Burn. And the 5 segment burn does not last only 5 seconds longer as you claimed; it lasts about 15 seconds longer. Basically, if ISP is unchanged and 25% more propellant is added, the total impulse goes up 25%. And that 25% extra total impulse has to lift only 20% more mass. 1. the max thrust of the standard SRB is 3.3 Mlbs. so, the new SRB has only +7% of peak thrust 2. the increase of peak thrust is only +7% while the increase of weight is +25% for the new SRB and +7% for the upperstages' mass 3. you may say that 3.5 Mlbs. (or also 3.3 Mlbs. of the old SRB) is enougb to lift the Orion... and I could agree with you... unfortunately, the REAL NASA CHOICES (clearly) say us that it's NOT enough (but I don't know why they think that, I've, simply, based my evaluations on their Ares-1 specs) 4. your calculations are not exact since the yellow curve is shifted right due to the 5 seconds extra burn time of the new SRB 5. without this "shift" the new SRB thrust seems enough for the job only between 60 to 80 sec. but the rocket must fly also before and after them 6. the +5 sec. extra burn time is NOT my claim but a NASA and ATK claim: http://blogs.orlandosentinel.com/news_s ... s_on_.html http://www.nasa.gov/centers/marshall/ne ... 3-186.html . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Moon Mission Member ![]() ![]()
Joined: Tue Oct 05, 2004 5:38 pm
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gaetanomarano wrote: [color=red]unfortunately, the REAL NASA CHOICES (clearly) say us that it's NOT enough gaetanomarano wrote: 4. your calculations are not exact since the yellow curve is shifted right due to the 5 seconds extra burn time of the new SRB |
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
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campbelp2002 wrote: gaetanomarano wrote: [color=red]unfortunately, the REAL NASA CHOICES (clearly) say us that it's NOT enough the data and drawings published in my article and posted here are ORIGINAL NASA DOCUMENTS but NASA also "talks" with "facts" and "choices" and that facts/choices "agree with me" just look at the Delta IV Medium specs: http://www.astronautix.com/lvs/deledium.htm this smaller rocket is able to lift an 8.6 mT payload to LEO despite the 1st stage engine has only 745 klbs. of thrust and must do great part of the work, since the Delta IV 2nd stage is very much smaller than the Ares-1 2nd stage so, if we want to lift the 25.5 mT of an Orion to LEO, we just need the power of only THREE Delta IV Medium, or just 2.2 Mlbs. of thrust then, the 3.3 Mlbs. (+50% the 3 x Delta IV Medium thrust) of a standard SRB should EXCEED the power to lift the Orion... but NASA (not me!) says with its FACTS and REAL CHOICES that a standard SRB has NOT enough power to lift the Orion... that's why they're developing a new SRB and cutting the Orion's weight every day I don't know why NASA engineers thinks (as it's clear from FACTS) that they need so much power... I've ONLY remarked that a new SRB is a BAD choice since it adds only +7% of thrust with +25% of extra-weight ALL my thoughts start from real NASA data, documents, facts and choices Quote: You simply do not know how to read a graph if you say something as patently false as that! if you "compress" the new SRB's yellow curve to match the old SRB curve, you'll see that (both) the ascending and descending power of the old and new SRB are very close (with differences around 10% max) and ONLY in the MIDDLE of the thrust (and flight) between 6o to 80 sec. (of the compressed yellow curve) the new SRB has a consistent increase of thrust the new SRB "seems" more powerful in the graph ONLY because its thrust curve is "shifted" +5 seconds right . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Moon Mission Member ![]() ![]()
Joined: Tue Oct 05, 2004 5:38 pm
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gaetanomarano wrote: I don't know why NASA engineers thinks (as it's clear from FACTS) that they need so much power... |
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Space Station Member ![]()
Joined: Thu Jan 12, 2006 12:28 am
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campbelp2002 wrote: gaetanomarano wrote: I don't know why NASA engineers thinks (as it's clear from FACTS) that they need so much power... I don't know why NASA wants/needs so much power but I've an hypothesis that I explain with an example: just imagine you must do a 100 miles travel with a truck and 10 tons freight the 100 miles road has slopes, plain and climbs but no gas stations also, your truck has not enough power to carry the same cargo on (both) a slope and a climb so, if your truck can carry 20 mT in a slope, 15 mT in a plain and 10 mT in a climb, the max freight you can carry in THIS travel is 10 mT ...if you want to arrive to the end of the road and don't stop at the first climb... probably NASA knows (from real data of real Shuttle flights) that a standard SRB (that can't "throttle" its thrust) CAN lift 250+ mT in some points of the thrust curve, but ONLY 182 mT in ALL points that's why NASA has calculated that the early CLV (based on a standard SRB and despite its 3.3 Mlbs. peak thrust) was able to lift ONLY 182 mT of upperstages' mass in ALL points of the 0 to 55 km. flight and that's why an heavier Orion and a lower thrust J-2X need a more powerful SRB (rather than just three Delta IV engines) but, if a standard SRB can't lift more than 182 mT (for reasons that only NASA knows) the 5-segments SRB is WORST since it give a +7% of thrust but ADDS a +25% of weight that a new SRB can't lift in ALL points of the flight, since, in one or more points (or "climbs" for your truck) it has NOT enough power . _________________ . Why the suborbital space tourism is TOO DANGEROUS . ghostNASA.com . gaetanomarano.it . |
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Space Walker ![]()
Joined: Sun Jul 29, 2007 5:18 pm
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I think we have established beyond all reasonable doubt that guantanamo is a Willfully Obtuse Person (WOP).
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