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#1 Re: Interplanetary transportation » Altair - Lunar Lander (LSAM) - status » 2008-04-19 11:46:39
my article and comments here are not about my "alternate ideas" but about analysis and critics regarding the NASA design of the Altair, so (both) the article and comments, are absolutely ON-topic ...or... now, I can't even post my opinions?
Your opinions were not posted here, you posted a link to your personal pages - this is self promotion and off topic for the status of Altair. Your offending message and my response have been removed.
there was nothing offending in my post and I don't need to post my links here since (from my blog's log) this forum adds just a few visits per month to my blog (compared with hundreds per week that come from other sites) so your discrimination ONLY of my links (but NOT of other 100% commercial sites like NSF, etc.) is unjust and a nonsense, since, censor me, doesn't allow the Altair to be good or the Ares-1 to fly (...not even "Direct" to succeed...)
I think time is arrived for me to stop posting here... goodbye
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#2 Re: Interplanetary transportation » Russia plan to build orbtial spacecraft construction yard? » 2008-04-19 10:02:59
a simply INSANE idea!!!!!!!!!!!!!!
work in space at zero gravity needs several time the physical effort, the problems and the time than do the same things on Earth, also, the orbital manufacturing workforce must be very specialized and with astronauts-like training, last, move to/from the orbital factory a giant number of workers can cost thousands times than move them from their houses to a factory on Earth
the right way is to build everything on Earth and assemble all parts in Space with the same skills shown by the Shuttle and ISS astronauts
unfortunately, this kind of ability will be completely LOST after 2010 when the Shuttles will be retired and no space-assemply-guys (nor "things to assemble") will be sent in Space 
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#3 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-19 03:56:02
I believe the risk is so significant that we shouldn't even bother testing it.
your personal opinion is not enough to be sure that a test is unnecessary
...they would have to be carried to orbit...
no, I've suggested to use the Orion thrusters to save mass, but, if the LAS needs more powerful thrusters, they can be designed to be jettisoned with the LAS
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#4 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-18 19:01:47
...attitude control jets on the Orion capsule simply can't produce enough thrust to guide the capsule...
the attitude control jets are a minimal part of the tower-LAS mass and very small in dimensions, so, it's not a problem to add them to the underside-LAS
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#5 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-18 18:58:36
...cause the capsule to enter an end-to-end tumble perpendicular to the axis...
you're right about the "spinning" but "how much" spin may come from a motor failure can be verified only with REAL tests, and, if it's not too much (maybe, in the range of 20-30 degrees) it can be used safely
the other things you say are only exagerations (to denigrate the underside-LAS) that have very low probability to happen
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#6 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-18 14:03:09
If you have an engine that has a 1 in 5 change of failing.
the solid motors have not a so low success rate... the SRB had just one failure in 240 SRB launched (and was not its ignition)
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#7 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-18 06:51:44
...spinning crazily around in the air...
depends from the "angle" of spinning, that we can't know before real tests
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#8 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-17 18:20:59
...if one of those 6+ motors fails, with the extremely high thrust they produce, the imbalance in thrust vector will knock the capsule into an unrecoverable spin...
"spin" is not so dangerous than a fails of the single rocket... however, my words and your word don't counts about this point since everything must be tested to know how much "spins"
...heavier than the single motor...
the case of REAL solid rockets of every dimensions is just around 10% of the total mass
...low-thrust attitude control motors on the capsule to control the ~10G LAS separation is nonsense...
add LAS thrusters doesn't change so much the mass saving since great part of the LAS wheigt come from its motor and big structure
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#9 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-17 18:12:51
Shuttle doesn't have one because the main tank and not the orbiter is at the tip of the whole vehicle
the shape an dimension of the orbiter have a great influence on aerodynamics and the ET hasn't/can't have a "tower" so, a tower is (maybe) useful but NOT indispensable atop the Orion
...if you are going to build a tower on top of Orion, why not put the LAS system there...
because the "aerodynamic tower" is not absolutely necessary and it's weight is a very small fraction of a LAS
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#10 Re: Interplanetary transportation » Ares I (CLV) - status » 2008-04-17 09:15:54
...wind shear and vibration...
yes, these (plus acceleration and stability) tests may be the only good reason to launch the Ares 1-X ...and to scrap the full project...
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#11 Re: Interplanetary transportation » >>> another "developed internally..." idea from NASA >>> » 2008-04-17 09:12:02
So things like your underside LAS needs to be put in this thread rather than the ones created for progress status.
no, since I've already posted about the underside-LAS in its own thread (IIRC) while, in the status thread, I've just compared the giant and heavy tower-LAS with the Tour Eiffel... 
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#12 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-17 09:05:55
...numerous abort motors mean increased risk of deadly failure...
no, since, despite it's four nozzles, the LAS has a single motor, and this single motor can fail, while, if one of the 6+ motors oif the underside-LAS fails, the Orion may have a sligtly curved trajectory, but the astronauts are saved
...the capsule is the same diameter as the rest of the Ares-I...
but the SM is smaller, so, there is enough space for the underside-LAS
...your terrible design...
it's only one of dozens possible designs
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#13 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-17 08:58:52
The tower actually lowers drag, by permitting the rest of the rocket to "hide" under the low-pressure region generated by the tip of the LAS tower. For example, the Trident-II ballistic missile
as you've already said, 99% of rocket launch have no "tower" not even the most launched spacecraft of the story: the Shuttle
also the Gemini was launched without a tower and with (also) a truncated-cone capsule top
however, assuming a "tower" may help, it doesn't need to be so BIG and 7+ mT heavy like the Orion LAS, but just a small and very light tower like the Trident pin
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#14 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-16 15:02:44
Every pound that can be transferred from capsule to LAS saves several pounds of capsule mass.
that's true, but there is no extra-pounds they can transfer from capsule to LAS... if you refer to the underside-LAS, well, it will be jettisoned exactly like the tower-LAS
And nobody is ever going to use the "underside LAS" because bolting anything to the heat shield is a terrible idea, and there would be too much equipment protruding into the service module.
as already explained in my articles and posts (that, clearly, you've not read) about the underside-LAS, it is NOT joined to the TPS but to the TPS protection cover (or structure) between the TPS and the SM
of course, the SM and the SM fairing need a different design to host the underside-LAS
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#15 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-16 14:54:57
Preliminary analysis shows that the new LAS increases payload by 545 kg.
it's not the LAS (that's is similar to the Apollo LES) but due to the more aerodynamic BPC shape
also, there is no better and more aerodynamic tower-LAS than... NO tower-LAS... and (you may like it or not) MY underside-LAS is the most aerodynamic possible (also more than a MLAS) since it's completely HIDDEN inside the SM fairing!
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#16 Re: Interplanetary transportation » Ares I (CLV) - status » 2008-04-16 14:51:16
help enormously to test proposed procedures and equipment
assuming you're right on this point, this doesn't mean that the real Ares-1 will fly, so, the experience gained with the 1-X will be useless... the problem is the rocket, not its launch... if the rocket works, launch it will be easy to do
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#17 Re: Interplanetary transportation » Ares I (CLV) - status » 2008-04-16 12:34:44
It's also a test of the ground support operations.
ground support is important but just a small part of all operations, also, nearly everything will be different with the real Ares-1 (launch pad, assembly, crawler operations, emergencies, astronauts safety, propellents fueling, etc.) so, the Ares 1-X experience will count pretty close to ZERO
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#18 Re: Interplanetary transportation » Ares I (CLV) - status » 2008-04-16 12:30:14
NASA seems to think launching a rocket with the same mass, same dimensions, and other similar properties as the real Ares-I is worth launching for testing.
WRONG... the DUMB upperstage mass of the Ares 1-X can't be the same of the Ares-1 SRB-5 since, the latter, is expected to lift MORE mass... also, the 5 segments SRB will have a DIFFERENT mass, thrust, Isp, burning time, nozzle, propellents' grain and shape, electronics, etc. ...in America you say: "it's like compare apples and oranges"
They are a legion of professional aerospace engineers. You are not.
that will make it MUCH MORE EMBARRASSING for them if/when the Ares-1 will not fly.. :oops: :oops: :oops:
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#19 Re: Interplanetary transportation » Ares I (CLV) - status » 2008-04-16 08:58:18
You had talked before (or more like whined) using 4 segmented boosters because the technology was available, well this is using what's available to do a test NOW to get some real information on how this thing'll fly.
this test WAS a great idea if accomplished in 2006 with a 4-seg. SRB based rocket in mind, while, a 4-seg. SRB test is useless since it will give poor data to know if the (real) 5-seg. SRB + J-2X rocket can/will fly
that's why a successful Ares 1-X launch is WORSE than a launch fail, since, a success may FOOL the engineers that might discover ONLY in 2013 (when the full Ares-1 will be tested) that the Ares-1 can't fly and that the (maybe, good) Ares 1-X data can't be applied to a completely different rocket
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#20 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-16 08:50:36
Unless you want excessive wind tunnel tests, I suggest you stow that underside booster idea.
why? ...my LAS design is the absolute BEST and it needs LESS wind tunnel tests
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#21 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-16 08:48:35
Looking at the aerodynamics of the LAS shroud, I think it is a logical step-up from Apollo.
no, it's too big and heavy, so, its aerodynamic advantage is small if compared with the extra-mass the rocket must lift
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#22 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2008-04-15 19:28:51
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NASA will soon realize that its tower-LAS is big and heavy like the Tour Eiffel... and will adopt something like MY underside-LAS...
#23 Re: Interplanetary transportation » Ares I (CLV) - status » 2008-04-15 19:18:41
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the Ares 1-X is an expensive, late and nearly useless test, since, if it will work well, that can't give any assurance that (also) the COMPLETELY DIFFERENT SRB-5 Ares-1 will really work, while, if it fails, the full ESAS plan should restart from ZERO and (both) the first Orion orbital flight and the first Altair landing will be delayed (at least) to 2020 (the first) and 2025 (the latter)
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#24 Re: Interplanetary transportation » >>> another "developed internally..." idea from NASA >>> » 2008-04-14 21:04:58
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another "developed internally..." idea from NASA to have a mass saving Orion's landing on LAND option:
http://www.ghostnasa.com/posts/028orionlanding.html
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#25 Re: Interplanetary transportation » in my opinion both Ares-I and Ares-V could NEVER fly once!!! » 2008-04-05 20:21:47
I think it would be good if NASA focused on Earth-to-LEO transportation first.
yes, I agree 100% ...it's my #1 point from my early space forums' posts! ... there is no difference between LEO and lunar vehicles since BOTH must reach the earth orbit first... the real difference is the PRICE to do that, and, unfortunately, that price is not changed so much in latest decades... the #1 effort and the #1 goal of all old.space and new.space companies MUST be: TRY to CUT the PRICE to launch something to LEO (no matter if using RLV or expendable vehicles) ... when this goal will be reached, EVERYTHING will be simple!
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