Ares I won't work, says John Young.

[no_way]

<blockquote><font class="small">In reply to:</font><hr /><p>I've never seen this slogan out of NASA itself <p><hr /></p></p></blockquote><br />huh .. Scott Horowitz is currently the director of Exploration Systems Mission Directorate, and he has talked about his beautiful safe simple and soon plan many times out in public. Thats "NASA itself"<br />

 

[qso1]

Fair enough. I just recalled seeing that associated with the OSP. I hadn't seen it on any documentation associated with Ares. Therefore, I stand corrected. But even with that, the slogan is just a slogan and someone at NASA was trying the Madison Avenue approach. I mean, look at advertising for cars on TV. So full of B.S. and B.S. slogans.<br /><br />But beyond that...to get back to the original point. John Young saying Ares won't work. Or more accurately, that it won't lift Orion as currently configured. This vehicle and spacecraft are still early enough in the design stage for this sort of thing to show up. Same stuff happened during early Apollo history. The LM was a constant source of irritation where its mass was concerned. And that vehicle had the giant Saturn-V to lift it to the moon.<br /><br />Now I would admit that the only thing here that does surprise me just a tad, is that with all the computer capability available for designing these LVs. This sort of fundamental error...assuming it is an error...would have to be pointed out by someone not even involved in designing the vehicle...and that of course, is assuming on my part, that John Young is not designing the Ares. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[jimfromnsf]

"Now I would admit that the only thing here that does surprise me just a tad, is that with all the computer capability available for designing these LVs. This sort of fundamental error...assuming it is an error...would have to be pointed out by someone not even involved in designing the vehicle...and that of course, is assuming on my part, that John Young is not designing the Ares"<br /><br />Has nothing to do with "designing" or "computers", it has to do with using a pork booster that can't be optimized.

 

[qso1]

Guess I'm having difficulty understanding how a perfectly decent booster suddenly can't do anything. It has thrust of a certain amount coming out its butt, right?<br /><br />The Ares is derived from shuttle ETs which have done their jobs all but one time.<br /><br />Modern day cad/cam systems are used among other computerized capabilities to design booster rockets these days. Among the most fundamental things one designs into a booster, or even takes an existing booster to see if it would work...payload mass and booster thrust. Calling it a pork booster is playing into the politics of the situation IMO and thats a no win situation. Whats the alternate political choice here? Design a completely new booster so NASA can be accused of spending money on new hardware when it has off the shelf hardware?<br /><br />I say if Ares cannot lift Orion as currently configured, beef up the thrust or add another stage and be done with it. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

I wouldn't be surprised. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[nyarlathotep]

<font color="yellow">Guess I'm having difficulty understanding how a perfectly decent booster suddenly can't do anything. It has thrust of a certain amount coming out its butt, right? </font><br /><br />Yes there's plenty of it, the problem is that it's coming out too slowly.<br /><br /><font color="yellow">Calling it a pork booster is playing into the politics of the situation IMO and thats a no win situation. Whats the alternate political choice here? Design a completely new booster so NASA can be accused of spending money on new hardware when it has off the shelf hardware?</font><br /><br />Buying an off the shelf Atlas 532 and shrinking the capsule to a sensible size. <br /><br />Lockheed should probably also consider buying some better lobbyists and coming up with a pithy slogan. "Safe Simple Soon", although being an accurate description of their vehicle, is already taken. Perhaps they could go with "Do we want to go to the moon or not?".

 

[qso1]

Nyarlathotep:<br />"Do we want to go to the moon or not?".<br /><br />Me:<br />I like that slogan! <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[thereiwas]

<blockquote><font class="small">In reply to:</font><hr /><p>I say if Ares cannot lift Orion as currently configured, beef up the thrust or add another stage and be done with it.<p><hr /></p></p></blockquote><br /><br />Or make Orion lighter. Take out the stuff that was added to make it serve more mission. Mars fooey.

 

[jimfromnsf]

"Lockheed should probably also consider buying some better lobbyists and coming up with a pithy slogan. "Safe Simple Soon", although being an accurate description of their vehicle, is already taken."<br /><br />That is not LM's slogan. It is ATK's for the Ares I/ESAS. Orion has nothing to do with it nor an accurate description of it. The ARES I is make Orion more complicated.<br /><br />Edited

 

[rocketman5000]

If you read it was mentioned it was already taken

 

[jimfromnsf]

"Guess I'm having difficulty understanding how a perfectly decent booster"<br /><br />It is not perfectly decent. The SRB was built as a thrust assist, not as a first stage. It is lacking as a first stage and the Ares I upperstage can't make up for all the shortfalls.<br /><br />Solids can't be changed easily, they have fixed dimensions. The Ares I booster has an additional segment to increase the thruct but what is needed, is more impulse and that is impossible with the current casings. <br /><br />The stick design was supposedly chosen for its "safe" design but there were "other" considerations too . Any other mods would negate the "safety" features of the design and make EELV's just as viable<br /><br />

 

[jimfromnsf]

"Or make Orion lighter. Take out the stuff that was added to make it serve more mission. Mars fooey."<br /><br />there is no difference between a lunar or Mars mission as far as the CEV design right now. Any "stuff" taken out affects the lunar missions

 

[Aetius]

It did seem like an uncharacteristic comment.

 

[j05h]

<i>> It did seem like an uncharacteristic comment. </i><br /><br />From Keith? Naaaa. He loves kicking the hornet's nest. <br /><br />Personally, I'm insulted by his comment. He's obviously refering to Collectspace and our blogging about John Young. You know what? We're all entitled to our opinions. Most of us pay taxes. It's obvious that NASA is having some serious issues with ARES. So? The establishment tells us to sit down and shut up. Thanks, Keith, you're just part of the game, sucker. When VSE/ESAS/ARES gets canned by the next Democratic president, you will be the first one screaming about how unfair it is. Or you'll say it's no fair when Sir Richard sets foot on Mars before NASA gets back to the Moon. Dinosaur. You and Jeff Bell should be roommates, you deserve each other.<br /><br />And you know what? I'll take John Young's opinion over Keith's, Jeff's or most anyone elses. He is a true trailblazer, unlike these professional whiners.<br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[qso1]

jimfromnsf:<br />It is not perfectly decent. The SRB was built as a thrust assist, not as a first stage.<br /><br />Me:<br />For shuttle this is true. And I would expect that some mods required would be the case for development in any other purpose and if I can think of this, surely aerospace degreed engineering teams can. So here I am, I'm not the sharpest tack in the tool box but if the job of designing a VSE shuttle derived LV fell to me. Whatever existing shortcomings exist in the current SRB design would be addressed first. Then, the fundamentals of rocket design would be addressed, and that is...can this stage in conjunction with the LV as a whole, lift the payload mass it was intended to lift? Resulting in a perfectly decent booster...not a perfect booster. Maybe not even good enough to compete with Atlas or Delta heavy...but decent.<br /><br />jimfromnsf:<br />Solids can't be changed easily, they have fixed dimensions.<br /><br />Me:<br />Liquid boosters are fixed as well and the solution is similar to fix both. In the case of an SRB, add a casing and whatever mods go with that such as shaping the propellant according to the new length. Liquid booster, longer tank and outer skin. Niether solution is terribly easy...but they are not that difficult given the VSE development time allotted.<br /><br />jimfromnsf:<br />The Ares I booster has an additional segment to increase the thruct<br /><br />Me:<br />Actually, adding a segment increases the burn time. In the shuttle SRB, IIRC, the propellant grain is something called a regressive grain which means the thrust tapers off during ascent, particularly through max Q. This is done to minimize ascent loads on the orbiter. Specific impulse, and I assume thats what you meant by impulse...is a function of the type of propellant used. This number varies with the mix ratio and chemical constituents of the propellant. Not the length or casing of the booster. In extreme cases the length or casing may come into play.<br /><br />Specific impu <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

vishniac:<br />Well, guys, what did I see the other day...<br /><br />Me:<br />Isn't this something (The excerpt in the post containing the comment above) that was written by Jeff Bell? If so...Jeff Bell, expected condition meaning, I don't put much stock in what he says either. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[mattblack]

Jeffrey Bell is a paradox; sometimes he says things that make complete sense, other times he stuns me with his negativity!! I mean, he rarely makes statements that are uninformed or ignorant, per se and he is always quick to tell us in GREAT detail what he doesn't like and doesn't want. But -- to my knowledge -- he's never told us what he DOES like and does want for the future of manned spaceflight. I know many of us are, in his eyes, "Space Cadets", but I'd dearly love to know what systems & procedures for the future of "Moon, Mars & Beyond" he does advocate!!<br /><br />His op-eds only ever hint at his true feelings and engineering preferences. So what's it to be, Mr Bell? You're not dumb and you're not un-informed -- help us out. Please... <div class="Discussion_UserSignature"> <p> </p><p>One Percent of Federal Funding For Space: America <strong><em><u>CAN</u></em></strong> Afford it!!  LEO is a <strong><em>Prison</em></strong> -- It's time for a <em><strong>JAILBREAK</strong></em>!!</p> </div>

 

[ctrlaltdel]

"Actually, adding a segment increases the burn time"<br /><br />I'm pretty sure adding another segment does little to the burn time, but the increased surface area inside the booster does increase the level of thrust.

 

[gunsandrockets]

<there is no difference between a lunar or Mars mission as far as the CEV design right now. Any "stuff" taken out affects the lunar missions><br /><br />NASA sized the CEV for a crew of six specifically because of Mars mission requirements even though the lunar mission only requires four crew. If the CEV were sized for four crew then the capsule could be as small as 4.3 meters in diameter instead of 5 meters. With no other changes except for scaling the mass of an entire CEV could be reduced by as much as 25% over the current CEV by using a smaller capsule.

 

[gunsandrockets]

5 segment SRB vs 4 segment SRB, more thrust or longer burn?<br /><br />It all depends on the size and shape of the cavity forming the burning surface in the fuel grain. Compared to a four segment SRB a five segment SRB could have more thrust or more burn time, or even a little more of both depending on the cavity.

 

[gunsandrockets]

BILE<br /><br />Man is Keith hostile. Hardly the way to win friends and influence people! I like nasawatch but sometimes he just let's the bile flow for no good reason. What's the point? His bile is more destructive than the 'noise' he complained about.

 

[qso1]

ctrlaltdel:<br />I'm pretty sure adding another segment does little to the burn time, but the increased surface area inside the booster does increase the level of thrust.<br /><br />Me:<br />If another segment is added, say one that increases the booster length by ten percent. This would mean a corresponding increase of ten percent surface area of propellant to burn lengthwise alone. Take a shuttle solid booster 149 feet long and increase that to 300 feet...twice the propellant mass to burn and it will burn at a pre determined rate. If the grain is shaped as in the current booster, there will be plenty more burn time. Otherwise, why even have a 149 foot booster if a 70 footer will do.<br /><br />There are of course other factors such as the shaping in solid propellant rockets, is it progressive, neutral, or regressive grain. The nozzle throat and exit diameter.<br /><br />As for thrust, the bulk of thrust is dependant on the exit nozzle diameter and for liquid engines, thrust that is partly produced by pressure within and on the combustion chamber surfaces.<br /><br />In solids, the internal surface area is a contributing factor as well. But if increased surface area alone were responsible for thrust, exit nozzles would not be required. In a garden hose, the best way to illustrate this is to imagine water running out of an open hose. Some of the pressure is generated by the force of the water against the inside of the hose.<br /><br />One can feel some pressure as the water runs out the hose. Now attach the metal squeeze handle attachment which concentrates the thrust of the water and it can be seen the bulk of the thrust depends on the design of the exit. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[jimfromnsf]

There is no "ifs ands or buts" Adding segments only increase thrust not duration.<br /><br />Titan solids: 5, 5.5 and 7 segments all burned for around 114-120 seconds. <br /><br />Shuttle 4 and 5 segment burn the same amount of time

 

[jimfromnsf]

"Me:<br />Liquid boosters are fixed as well and the solution is similar to fix both. In the case of an SRB, add a casing and whatever mods go with that such as shaping the propellant according to the new length. Liquid booster, longer tank and outer skin. Niether solution is terribly easy...but they are not that difficult given the VSE development time allotted."<br /><br />Liquid boosters are easier to increase total impulse. Atlas and Deltas have streached their tanks in the past fairly easily.

 

[rocketman5000]

A brief lesson in fluid dynamics:<br /><br />The force on the hose from the exiting water is because of momentum. Momentum being the product of mass and velocity of the liquid. At the exit of the hose the pressure of the water is always expands until it matches the pressure of the atmosphere around it. By placing the nozzle (metal squeeze handle) on the end of the hose you trade the water pressure that is in the hose for velocity. If the nozzle is designed correctly you will get the exactly the same pressure in the hose at the exit as you have in the surrounding atmosphere and you will have maximized the momentum. <br /><br />When you hold your hand in front of the stream of water the force you are feeling is due to the change in momentum of the water, and not the pressure of the water stream. This force will be equal to the product of mass flowrate of the water and the change in velocity of the water.<br /><br />I'd continue to relate this back to the "Stick" but I am at work and unfortunately must do some.