savuporo - 7/1/2008 8:55 AMQuoteMATTBLAK - 7/1/2008 1:51 AMAnd it's for this reason that many of them are keeping quiet -- they may not actually lose their jobs for speaking out against Ares 1I have nothing against DIRECT, and voted for it, but this sounds awfully like a conspiracy theory, which i have become to dismiss immediately, unless some solid proof is supplied.Without any actual evidence of voice suppression in this matter, i would guess they are quiet because they feel theres nothing to shout about.
MATTBLAK - 7/1/2008 1:51 AMAnd it's for this reason that many of them are keeping quiet -- they may not actually lose their jobs for speaking out against Ares 1
Steven Pietrobon - 8/1/2008 3:37 AMThe main elements of Direct are the 1) Current 8.4 m diameter external tank (ET) modified to accept two or three crew-rated RS-68 engines operating at 100% thrust at the base and a forward skirt at the top2) Existing four segment solid rocket boosters (SRB)3) New Earth departure stage (EDS) with two J2-XD engines with standard turbo-pumpThe Jupiter 120 has two RS-68 engines and no upper stage, while the Jupiter 232 has three RS-68 engines and an upper stage. The main elements of Ares-I/V are1) New 10 m diameter main stage with five crew-rated RS-68 engines operating at 106% thrust.2) SRBs modified with five segments.3) New EDS with one J2-X engine with modified turbo-pump for increased thrust4) New Ares-I upper stage with one J2-X engine....In Direct, a Jupiter 232 is first launched only carrying the EDS. The payload here is 98.3 t of propellant. A second Jupiter 232 is launched carrying the CEV, LSAM and 20.5 t of liquid oxygen (LOX) in a tank under the LSAM. This stack docks with the EDS and the LOX is transferred to the EDS.
HIP2BSQRE - 7/1/2008 9:13 PMI think people really have to look at what the US "might" get for the next 30 years:1. Direct---Takes the US to the Moon and beyound.2. EELV: Great rocket---but to take the US to the moon? Is it time for lego.3. Ares I: Stuck in LEO for the next 30 years.I am not saying Direct is the end all, but REALLY think what spend money today, we might be flying for the next 30 years. If you want Ares fine, but in 5 years don't complain when we don't get it's big brother and we are stuck flying in LEO.
JonSBerndt - 7/1/2008 7:10 PMQuotemike robel - 7/1/2008 4:00 PMAfter due thought, I had to vote for I am not qualified to offer an opinion. BUT, as I have learned that most proposals change after they are accepted by the government, I have to think that current option 4, it would need major changes to be accepted by NASA is most likely.Chuck or Ross - maybe you could remind us to what degree DIRECT is a derivative of the NASA/MSFC LV24/25 concept? Reading some of these responses, it seems that some of the "pedigree" of DIRECT is being overlooked.Jon
mike robel - 7/1/2008 4:00 PMAfter due thought, I had to vote for I am not qualified to offer an opinion. BUT, as I have learned that most proposals change after they are accepted by the government, I have to think that current option 4, it would need major changes to be accepted by NASA is most likely.
kraisee - 8/1/2008 8:45 AMDIRECT v2.0 went right back to the original drawing-board, again including LV-24/25 at its heart. We started with nothing more than a passing resemblance to the previous version, and the utter determination to pack the whole system - performance, cost and schedule alike - with extra margins everywhere we could.
rsp1202 - 8/1/2008 12:52 AMThis whole thread is based on one person's negative bias. What a joke. It's beneath this forum.
JIS - 8/1/2008 2:03 AMAlso the use of RS-68B is actually an advantage as it improves reliability and keeps commonality with future EELV. It will be wise for DIRECT to accept this option. Otherwise it would have to human rate both versions.
clongton - 8/1/2008 1:07 PMQuoteJIS - 8/1/2008 2:03 AMAlso the use of RS-68B is actually an advantage as it improves reliability and keeps commonality with future EELV. It will be wise for DIRECT to accept this option. Otherwise it would have to human rate both versions.JIS;You should know better. There won’t be 2 versions of the RS-68, only one. Currently, the RS-68 is flying hardware, and the RS-68B, as you call it, is a paper engine. If and when that engine becomes real hardware, the existing RS-68 will be retired and then the new one will be used exclusively by all launch vehicles that employ the RS-68.
TrueGrit - 8/1/2008 12:03 PMjust to note... Delta IV Heavy with the upgraded RS-68's will achieve 27,000kg to ISS. Two fairly simple developments beyond this would be the addition of GEM's and the development of the ULA advanced upper stage concept which would increase performance to ~40,000kg. Beyond that I think the you need to go to either a 5-body booster, or more preferable 7-m booster with twin RS-68s. But this is where Jupiter/DIRECT starts to look more appealing...
TrueGrit - 8/1/2008 10:11 AMI've got to disagree with the idea that cargo and manned were a cause of either shuttle failure. The whole purpose of manned spaceflight isn't to see if we can get there. We've got get beyond the concept of manned spaceflight being one based on "flag planting", and one based on advancing our knowledge. Whether it be monitoring the climate, to investigating growing crystals in microgravity, or investigating the geology of other planetary bodies. The goal of having people in space isn't an end in and of itself, but what they can do once there. For example look at the pilots who fly P-3's into a hurricane... The plane outiftted for science, not for the thrill of playing daredevil. The Columbia mission cargo was exactly that, one of scientific investigation... Whether what they were doing couldn't be better done by a unmaned vehicle, or was worth their lives isn't the question. The fact is there is some science that is worth the risk, and some that is best done by a human in the loop. Therefore by designing a vehicle who's only purpose is to put people in space completely forgets the reason why we're are investing billions of tax money on the space program. Ares I not only redundant with existing capability, but completely forgets about the whole purpose of having a public space agency... To return that investment back to the general public. Without science package to go along with man in space it's nothing more than daredevil ride... And like bungee jumping not something for the government to be investing in.
khallow - 8/1/2008 2:48 PMQuoteTrueGrit - 8/1/2008 10:11 AMI've got to disagree with the idea that cargo and manned were a cause of either shuttle failure. The whole purpose of manned spaceflight isn't to see if we can get there. We've got get beyond the concept of manned spaceflight being one based on "flag planting", and one based on advancing our knowledge. Whether it be monitoring the climate, to investigating growing crystals in microgravity, or investigating the geology of other planetary bodies. The goal of having people in space isn't an end in and of itself, but what they can do once there. For example look at the pilots who fly P-3's into a hurricane... The plane outiftted for science, not for the thrill of playing daredevil. The Columbia mission cargo was exactly that, one of scientific investigation... Whether what they were doing couldn't be better done by a unmaned vehicle, or was worth their lives isn't the question. The fact is there is some science that is worth the risk, and some that is best done by a human in the loop. Therefore by designing a vehicle who's only purpose is to put people in space completely forgets the reason why we're are investing billions of tax money on the space program. Ares I not only redundant with existing capability, but completely forgets about the whole purpose of having a public space agency... To return that investment back to the general public. Without science package to go along with man in space it's nothing more than daredevil ride... And like bungee jumping not something for the government to be investing in.Let's also keep in mind that science while of some value, isn't in itself going to lead to sustainable activities in space. For that you need someone making money from doing something in space.