Augustine commission/Ares alternatives

[Orbinaut Pete]

You can use a Fiat 500 test vehicle to make reasonable predictions of the Fiat 500, just like Ares1X is used to predict Ares1.

But, I don't think you understand:

Ares I-X has no commonality with Ares-I.
The only thing Ares I-X has in common with Ares I, is it's shape (which can be accurately simulated in a computer model).

Ares I-X has no 5-seg SRB, it has no upper stage, it has no Orion CM separation test.

According to NASA, the supposed "objectives" of the "test flight" are:

. Demonstrating control of a dynamically similar vehicle using control algorithms similar to those used for Ares I.
-Could this not be done using a computer simulation? They never felt the need to test the Shuttle like this.

. Performing an in-flight separation/staging event between an Ares I-similar First Stage and a representative Upper Stage.
-What??? The only staging event will be the separation between the SRB & the upper stage. But, haven't we been successfully separating 4-seg SRB's for the last 30 years on the Space Shuttle anyway? Why test something we already know works?

. Demonstrating assembly and recovery of an Ares I-like First Stage at KSC.
-Again, haven't we been successfully assembling & recovering 4-seg SRB's at KSC for the last 30 years? Do we really need to test what we already know we can do?

. Demonstrating First Stage separation sequencing, and measuring First Stage atmospheric entry dynamics, and parachute performance.
-And again, haven't we already done this with 4-seg SRB's on the Shuttle for the last 30 years?

. Characterizing the magnitude of integrated vehicle roll torque throughout First Stage flight.
-But these "results" won't be any use in aiding the design of Ares-I, because no 5-seg SRB was used, no fuelled upper stage was present, and no Orion CM was present. So the "results" will not represent the actual Ares-I

Ares I-X is nothing more than a Shuttle SRB with a hollow white tube atop it. :facts:

If you would like to learn more about the real Ares I-X, then I suggest you read some of the documentation:

> Ares I-X Fact Sheet (PDF, 1.0 MB)
> Ares I-X Mission Specification (PDF, 8 MB)

 

[Moonwalker]

And besides, I'm paying for it, so I will speak out if I don't like it, period.

It is always interesting when people start to complain about the few cents they spend for space flight. You should rather complain about the money you spend for supporting war and environental pollution.

@Orbinaut Pete

you don't tell me anything new. Save your time. I know about Ares I-X.

I won't agree to those "it's useless" phrases.http://orbiter-forum.com/member.php?u=1296

 

[Urwumpe]

And besides, I'm paying for it, so I will speak out if I don't like it, period.

I don't pay for it, but I have the chance to see my taxes invested into a German lunar robotic mission (likely a rover), of estimated 1.5 billion € value... while the CDU claims that they are planning to push this through after the election (and they could almost get me by that), they won't decide but the science committee before the election...

I see these 1.5 billion as a way to ensure my income in the future.

PS: On the VAB guy example: I worked for the German Aerospace Center. But not as engineer and not in spaceflight... I developed software for designing lightweight composite structures in aircraft, especially high-performance aircraft. :lol:

And I take all my authority on spaceflight issues from the fact that I serviced the computers of the engineers who designed the Philae structures, especially the landing gear.

 

[reject]

Yes. Even the guy cleaning the floor inside the VAB can claim and post anything across the web.

In case a real NASA person expresses concerns, which by far is not unusual, does not mean anything. Apollo had its opponents as well, at a time without the internet (luckily). Edgar Mitchell (Apollo 14) even talks about aliens and that NASA is hiding important informations and discoveries. Others who worked on Apollo even contribute to the Moon landing conspiracy theorie. Others who worked on STS in the past also said not too good things about NASA and the program in interviews.

Er. If you were able to make specific rebuttals to his claims your argument might have some more credibility. Instead your attitude is that the opinion of anybody not singing from the official NASA songsheet "does not mean anything". Just like those pesky Thiokol engineers saying their O-Rings wouldn't work in cold temperatures, or NASA engineering wanting to photograph Columbia's wing after a foam strike. Why listen to the opinion of these stupid militants at all?

 

[Urwumpe]

Let me clarify the impact of the differences a bit more.

According to NASA, the supposed "objectives" of the "test flight" are:

. Demonstrating control of a dynamically similar vehicle using control algorithms similar to those used for Ares I.
-Could this not be done using a computer simulation? They never felt the need to test the Shuttle like this.

The Shuttle has a different guidance algorithm and other linear stacked rockets have less instability in their design - the Ares I will be very top-heavy, and have a unusual high distance between Center of Pressure and center of gravity, or center of gravity and thrust reference. This will mean, the dynamic behavior of the control loops will be absolutely different, you could for example have singularities around Max-Q flight, which could make the Ares I-X oscillate out of control.

Still, you also can't compare the Ares I to the Ares I-X, even though they suffer from the same problems: The Ares I will have liquid fuel in the upper stage, which is sloshing, the additional fuel segment will have impact on the CoG position at the critical phases - other than the mass dummy used, the real segment will become lighter over time changing the frequencies of the vibrations and the position of the singularities in the control loops.

The characteristic function of the Ares I control loop will be completely different to the Ares I-X, as only the aerodynamic effects are the same.

Also, the TVC of the SRBs is much slower than the TVC on liquid fueled rocket engines (by design) and will contribute to instability.

. Performing an in-flight separation/staging event between an Ares I-similar First Stage and a representative Upper Stage.
-What??? The only staging event will be the separation between the SRB & the upper stage. But, haven't we been successfully separating 4-seg SRB's for the last 30 years on the Space Shuttle anyway? Why test something we already know works?

SRBs did lateral separation only for a while and even though we know how to do this, things can go wrong. Still, the Ares I-X does not include sloshing torques of the Ares I and not the many forces of the additional segment of the SRB, once there is burning fuel inside it. Without sloshing, the separation is easy, but once you have to include it, it can ram the engine nozzle against the separating stage, or make the mechanical parts of the separation fail. This is especially important since the Ares I will have much stronger vibrations than the Ares I-X.

. Demonstrating assembly and recovery of an Ares I-like First Stage at KSC.
-Again, haven't we been successfully assembling & recovering 4-seg SRB's at KSC for the last 30 years? Do we really need to test what we already know we can do?

Is really the same as for the shuttle, the only difference is the interstage with the ARCS.

. Demonstrating First Stage separation sequencing, and measuring First Stage atmospheric entry dynamics, and parachute performance.
-And again, haven't we already done this with 4-seg SRB's on the Shuttle for the last 30 years?

Yes, but there are tiny differences. Really tiny though.

. Characterizing the magnitude of integrated vehicle roll torque throughout First Stage flight.
-But these "results" won't be any use in aiding the design of Ares-I, because no 5-seg SRB was used, no fuelled upper stage was present, and no Orion CM was present. So the "results" will not represent the actual Ares-I

Yes, the fuel inside the upper stage can have an amplifying effect on the roll torque, especially when coupled with strong vibrations. Especially if you have inadequate vortex baffles, like can easily happen if you are forced to save weight. Induce a small rotation moment in the fuel during first stage flight and the real forming vortex could be much stronger than you designed for without taking these initial rotations in consideration.

 

[Moonwalker]

The 5-segment Ares1 SRB is a single first stage that is being separated from the upper stage in a totally different way than those two SRB's from the ET, which are stacked in a totally different configuration. Also, the Ares first stage is taller than the whole Shuttle stack and heavier than a Shuttle SRB. It propably has different aerodynamic and entry characteristics.

But these "results" won't be any use in aiding the design of Ares-I, because no 5-seg SRB was used, no fuelled upper stage was present, and no Orion CM was present. So the "results" will not represent the actual Ares-I

What about the colours? Ares 1-X does not appear in the same colours than Ares1...

Seriously: the masses of the Ares-1X components correspond to the masses of the Ares1 components.

 

[Urwumpe]

Seriously: the masses of the Ares-1X components correspond to the masses of the Ares1 components.

No, it does not. The launch masses are slightly similar (but I think already outdated, since the Orion spacecraft gained more weight than Elvis in the last years), but at separation, the masses are not. Also the moments of inertia will be different, especially because you have no liquid fuel in the upper stage and no slowly burning solid fuel in the 5th segment dummy. The bending behavior of the dummy parts will also be different, so you can expect the reaction of the control loops being different as well. But the control loop reaction can't be reliable simulated on the computer as small differences in the dynamic behavior cause big differences in the stability of the control loops.

Which brings us back to the Fiat 500 - it weights almost the same as the formula one car of Ferrari.

 

[Moonwalker]

So you think that water does not have an amplifying effect on the roll torque?

 

[Insane]

The naivity actually is that in this topic even just mannd space flight fans instantly become experts and arrogate to know everything better than NASA and those who work on that stuff.

I am by no means anything even approaching close to an expert. Yet still I recognise that there is no logical argument to proceed with Ares I. And there are plenty of logical arguments to kill it. You don't have to be a rocket scientist to look at the basic facts surrounding Ares I, its costs, its schedule, its original purpose, its transformation from something Shuttle Derived and Ares V related to something Shuttle Underived and Ares V Unrelated. It makes no sense. Without even looking at any technical aspects at all, it just clearly makes no sense.

That's still dreams of the future. SpaceX is anything but close to launch crews into orbit.

Quite true. SpaceX are not the only players here though. And I wouldn't bet against them either.

I have not enough time yet to respond to everything. But specualtions actually do not make sense anyway, less than ever on this place here, because I'm not more or less expert than anybody else here, or those who think to be. We'll see what happens. But I risk to prophesy that most likely a budget increase will take place. And in case Ares will be scraped, nothing is going to lift off from the KSC anytime soon...

A budget increase has to take place if any exploration is going to occur. If that budget is to be maxmised, Ares I and preferably Ares V as well are going to have to be culled.

I find it bizarre that you think Ares I is the only method of lifting crews off the ground in the near future. The Space Shuttle infrastructure still exists. It's still there. And there are two heavily Shuttle Derived launch options that utilise that infrastructure. Not because they're job saving schemes, as you continue to mistakenly assume, but because they make best use of a system that has been in place for 30 odd years, and which ALREADY EXISTS, in a far fuller form than any infrastructure to support Ares I does, let alone Ares V.

 

[Urwumpe]

So you think that water does not have an amplifying effect on the roll torque?

Assignment for today: Compare the viscosity and density of liquid hydrogen, liquid oxygen and water.

 

[zerofay32]

The past couple weeks, the sidemount option has grown on me. But I still feel that Direct meets the goals better than both Sidemounts and Ares. My too cents, take it as you will.

Zerofay32

 

[Urwumpe]

The past couple weeks, the sidemount option has grown on me. But I still feel that Direct meets the goals better than both Sidemounts and Ares. My too cents, take it as you will.

I can just agree - the Sidemount is closer to the Shuttle, Direct is the better architecture, when it comes to work flow. Ares is neither of both - it is extremely annoying to build and operate, even if from now on all works perfect, and still far away from the shuttle architecture.

 

[Insane]

The past couple weeks, the sidemount option has grown on me. But I still feel that Direct meets the goals better than both Sidemounts and Ares. My too cents, take it as you will.

Zerofay32

I'm in agreement with you there. Sidemount is better than nothing, and is sustainable. The irony is that the Inline vs Sidemount SDLV argument has been done a few times before by NASA itself, and the results have each time come out in favour of Inline. Fingers crossed that will be the case again here. But if Sidemount is chosen, at least it isn't Ares I. The only problem is that it won't allow for an Altair sized lander, but since the moon is off the objectives anyway, who cares.

Moonwalker - Notice that on the link reject provided, there are no arguments to his or her claims afterwards. Criticisms, yes, but criticisms with no content or actual argument against ANY of the points made. Here they are:

1.

Without going into a diatribe, I will just say that CornDog Rocket is a bitter little man that knows not of which he speaks.

Wow.

2.

@ Corndog Rocket "I am a space shuttle flight controller at the top of my game"
Translation: Shuttle Hugger, who believes the destination is LEO

Right.


These are all the arguments that could be mustered.


Anti Ares people don't just argue against "the system, maaan" to get a kick out of it. They do it because they have good cause. I have the opinion that I have because I've looked at all the arguments and evidence, and believe that that opinion is the one most firmly established in fact. If a pro Ares argument had any substance, I'd listen to it and take it on board. But they don't. They're based on "Nasa knows best" dogma, that it's already built so it should continue, that anything else is just a paper rocket, that the very future of US human spaceflight depends on Ares I! Are any of these arguments even remotely convincing?

 

[Andy44]

Sidemount certainly seems more logical on the face of it. It takes the most advantage of current shuttle infrastructure, delivers a healthy 70 tons or so to LEO, and allows for a heavier Orion, which is almost inevitable. It is also useful for many missions other than just crew launch and has limited room for growth, while Ares I seems not to.

Problem is they should've thought of this stuff 4 years ago and got started on it. Now that so much money has been sunk into Ares it's hard to argue past the sunken cost fallacy and change course. And every change delays return to flight. Perhaps Sidemount would make a small shuttle extension easier to swallow. No matter what eventually is built it will be mired in politics and bureaucracy and therefore delayed and over budget.

PS: Anyone aware of a Sidemount addon project? Seems like a neat near-future tech addon.

 

[Urwumpe]

PS: Anyone aware of a Sidemount addon project? Seems like a neat near-future tech addon.

No, but it would be possible to do it in the scope of SSU, as final evolution of the Shuttle-C.

 

[Andy44]

No, but it would be possible to do it in the scope of SSU, as final evolution of the Shuttle-C.

Cool. You guys do great work on SSU. Now back to our regularly scheduled topic...

 

[zerofay32]

Has anyone heard of what the abort options for a sidemount would be? Or have they not delved into the topic that far...

That is my main concern with sidemounts. If the abort options are the same as inline launchers then I would almost want to say that I would prefer sidemounts. But if the aborts are similar to STS, then I would definatly favor Direct.

Zerofay32

 

[Andy44]

Well, in the videos the capsule has a top-mounted LES, so it appears the abort method is the same as a conventional rocket.

 

[zerofay32]

Well, in the videos the capsule has a top-mounted LES, so it appears the abort method is the same as a conventional rocket.

I guess another "less desirable" feature of the side mount is the MPS is not recovered. One consept with Shuttle-C was having the SSMEs and aft compartment able to re-enter and be recovered for reuse.

Oh well, just have to wait to see what happends. I hope that a side mount add-on gets made.

Zerofay32

 

[Orbinaut Pete]

Has anyone heard of what the abort options for a sidemount would be? Or have they not delved into the topic that far...

NASA (being NASA ) have already done a study into it!

Read this: (PDF, 3.3 MB)
http://images.spaceref.com/news/2009/hlv.abort.pdf


This document is un-related to sidemount aborts, but is also intersting: (PDF, 2.3 MB)
http://www.nasa.gov/pdf/361842main_15 - Augustine Sidemount Final.pdf

(More documentation on Ares alternatives can be found here):
www.nasa.gov/offices/hsf/related_documents/index.html

---------- Post added at 23:23 ---------- Previous post was at 23:12 ----------

I hope that a side mount add-on gets made.

Here's a few shots of Donamy's latest work.

Orion VC: :speakcool: