SpaceX Falcon I - Flight 3 Launch Failure T+2:20

[shuttle_guy]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>..............................An open truss for the interstage has been considered, but I don't know of any design like that that has flown.&nbsp; There would be some serious aerodynamics to consider before jumping into that.&nbsp; ............................. <br />Posted by DrRocket</DIV></p><p>&nbsp;I think several Russian vaunch vehicles such as the Soyuz booster have a open truss between the first and secon stage.<br /></p> <div class="Discussion_UserSignature"> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If the Space-X design can be pulled apart vertically at any time then that is a most unusual design, and I don't understand the role of the explosive bolts in such a design.&nbsp;&nbsp;&nbsp; But the tight discipline is absolutely crucial and Space-X has demonstrated that they simply don't have it. <br />Posted by DrRocket</DIV><br /><br />Hi Dr Rocket. I think you are being too harsh on a startup. Granted, they have much history to learn from, but it still takes the baby steps. How successful were the first dozen or so NASAattempts, even using proven designs such as Redstone? IRC, the answer is, not very. Give them some time to learn the process. If we had given up on Mercury, Gemini and Apollo at this point, we never would have ventured even into orbit, much less to the moon.</p><p>It takes time for lessons to be learned. NASA was far fro perfect. Can you at leat cut SpaceX the same amount of slack?</p><p>After all, they haven't killed anyone yet. Like it or not, that is part of the legacy of space exploration....</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If the Space-X design can be pulled apart vertically at any time then that is a most unusual design, and I don't understand the role of the explosive bolts in such a design.&nbsp;&nbsp;&nbsp; But the tight discipline is absolutely crucial and Space-X has demonstrated that they simply don't have it. <br />Posted by DrRocket</DIV><br /><br />Hi Dr Rocket. I think you are being too harsh on a startup. Granted, they have much history to learn from, but it still takes the baby steps. How successful were the first dozen or so NASAattempts, even using proven designs such as Redstone? IRC, the answer is, not very. Give them some time to learn the process. If we had given up on Mercury, Gemini and Apollo at this point, we never would have ventured even into orbit, much less to the moon.</p><p>It takes time for lessons to be learned. NASA was far fro perfect. Can you at leat cut SpaceX the same amount of slack?</p><p>After all, they haven't killed anyone yet. Like it or not, that is part of the legacy of space exploration....</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hi Dr Rocket. I think you are being too harsh on a startup. Granted, they have much history to learn from, but it still takes the baby steps. How successful were the first dozen or so NASAattempts, even using proven designs such as Redstone? IRC, the answer is, not very. Give them some time to learn the process. If we had given up on Mercury, Gemini and Apollo at this point, we never would have ventured even into orbit, much less to the moon.It takes time for lessons to be learned. NASA was far fro perfect. Can you at leat cut SpaceX the same amount of slack?After all, they haven't killed anyone yet. Like it or not, that is part of the legacy of space exploration.... <br />Posted by MeteorWayne</DIV></p><p>No, I can't.&nbsp; There&nbsp; have been tremendous advances in engineering capability since those early days of rocketry.&nbsp; We now have readily available finite element analysis, advanced control theory, sophisticated 3 and 6 degree of freedom trajectory codes, advanced computational fluid dynamics codes, materials that were unheard of in the early days, many lessons learned from mistakes made in that era, etc.&nbsp; But most importantly there is an understanding of the engineering and review steps that can be applied to design a rocket so as incorporate all of these advances&nbsp; and not duplicat past failures.&nbsp;&nbsp;Space-X has demonstrated either total disregard or total ignorance towards these advances and the result is a thoroughly amateurish approach to rocket development.&nbsp; There is no excuse for having a failure as the result of a totally predictable series of events.&nbsp; If you can't avoid the obvious failure modes, you have no chance of avoiding the subtle ones.</p><p>Not learning from mistakes made in the&nbsp; past is a mark of incompetence.&nbsp; There is no good excuse for reverting to the design practices of 50 or more years ago and ignoring all the benefits that ought to be available from the mistakes that others have made.&nbsp; If commercial space enterprises are ever to make a real go of it, they need to benefit from the past and not recreate it.&nbsp; Space-X is setting a very bad example.&nbsp;&nbsp;And it is the approach that results in these failures that is the real problem, more so than the failures themselves.&nbsp; In the case of Space-X the process is the problem</p><p>If Hyundai had started out building model Ts would you "cut them some slack"?&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hi Dr Rocket. I think you are being too harsh on a startup. Granted, they have much history to learn from, but it still takes the baby steps. How successful were the first dozen or so NASAattempts, even using proven designs such as Redstone? IRC, the answer is, not very. Give them some time to learn the process. If we had given up on Mercury, Gemini and Apollo at this point, we never would have ventured even into orbit, much less to the moon.It takes time for lessons to be learned. NASA was far fro perfect. Can you at leat cut SpaceX the same amount of slack?After all, they haven't killed anyone yet. Like it or not, that is part of the legacy of space exploration.... <br />Posted by MeteorWayne</DIV></p><p>No, I can't.&nbsp; There&nbsp; have been tremendous advances in engineering capability since those early days of rocketry.&nbsp; We now have readily available finite element analysis, advanced control theory, sophisticated 3 and 6 degree of freedom trajectory codes, advanced computational fluid dynamics codes, materials that were unheard of in the early days, many lessons learned from mistakes made in that era, etc.&nbsp; But most importantly there is an understanding of the engineering and review steps that can be applied to design a rocket so as incorporate all of these advances&nbsp; and not duplicat past failures.&nbsp;&nbsp;Space-X has demonstrated either total disregard or total ignorance towards these advances and the result is a thoroughly amateurish approach to rocket development.&nbsp; There is no excuse for having a failure as the result of a totally predictable series of events.&nbsp; If you can't avoid the obvious failure modes, you have no chance of avoiding the subtle ones.</p><p>Not learning from mistakes made in the&nbsp; past is a mark of incompetence.&nbsp; There is no good excuse for reverting to the design practices of 50 or more years ago and ignoring all the benefits that ought to be available from the mistakes that others have made.&nbsp; If commercial space enterprises are ever to make a real go of it, they need to benefit from the past and not recreate it.&nbsp; Space-X is setting a very bad example.&nbsp;&nbsp;And it is the approach that results in these failures that is the real problem, more so than the failures themselves.&nbsp; In the case of Space-X the process is the problem</p><p>If Hyundai had started out building model Ts would you "cut them some slack"?&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[vattas]

<p>OK, only time will tell if SpaceX is successful...</p><p>I noticed in the launch video that after some time rocket starts to rotate (not sure if it's the right term) back and forth along it's axis. Is that normal? I've seen videos from other small launch vehicles, theyr'e not as stable as big ones, but what is seen on SpaceX video, seems like fuel sloshing again and reaction control compensating (but not overcompensating like last launch 2nd stage) </p>

 

[vattas]

<p>OK, only time will tell if SpaceX is successful...</p><p>I noticed in the launch video that after some time rocket starts to rotate (not sure if it's the right term) back and forth along it's axis. Is that normal? I've seen videos from other small launch vehicles, theyr'e not as stable as big ones, but what is seen on SpaceX video, seems like fuel sloshing again and reaction control compensating (but not overcompensating like last launch 2nd stage) </p>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>OK, only time will tell if SpaceX is successful...I noticed in the launch video that after some time rocket starts to rotate (not sure if it's the right term) back and forth along it's axis. Is that normal? I've seen videos from other small launch vehicles, theyr'e not as stable as big ones, but what is seen on SpaceX video, seems like fuel sloshing again and reaction control compensating (but not overcompensating like last launch 2nd stage) <br />Posted by vattas</DIV></p><p>It could be an effect of sloshing of fuel.&nbsp; It could be a problem with the control system parameters.&nbsp; It could be a combination of both.&nbsp; You could cause that by having something like sloshing driving the system and then have the control loop gain turned up too high and essentially be overcompensating a bit.</p><p>In order to get faster response in a control system you can turn up the loop gain.&nbsp; But that also tends to drive the system closer to instability.&nbsp; It is a trade-off.&nbsp; </p><p>What you are describing is a rotation.&nbsp; A missile, like an aircraft can rotate in three axes -- pitch, yaw and roll.&nbsp; The distinction between pitch and yaw for a cylindrical missile is a bit artificial, and this is one of them.&nbsp; Rotation about the long axis of the rocket is roll.&nbsp; In an airplane flying level, pitch is up and down about the axis through the wings, yaw is side to side about and axis that is vertical with respect to the fuselage, and roll is rotation about the long axis.</p><p>What I saw on the video seemed to be a little bit of roll being compensated by a roll control system, presumably from the second stage cold gas roll control system.&nbsp; I did not see any significant pitch or yaw and I did not see any rapid movements of the plume, which would have been indicative of control action in the pitch or yaw planes.&nbsp; I did not see anything of major concern until the staging event, recontact, and failure.</p><p>I also head a bunch of sound that I suspect was dubbed in.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>OK, only time will tell if SpaceX is successful...I noticed in the launch video that after some time rocket starts to rotate (not sure if it's the right term) back and forth along it's axis. Is that normal? I've seen videos from other small launch vehicles, theyr'e not as stable as big ones, but what is seen on SpaceX video, seems like fuel sloshing again and reaction control compensating (but not overcompensating like last launch 2nd stage) <br />Posted by vattas</DIV></p><p>It could be an effect of sloshing of fuel.&nbsp; It could be a problem with the control system parameters.&nbsp; It could be a combination of both.&nbsp; You could cause that by having something like sloshing driving the system and then have the control loop gain turned up too high and essentially be overcompensating a bit.</p><p>In order to get faster response in a control system you can turn up the loop gain.&nbsp; But that also tends to drive the system closer to instability.&nbsp; It is a trade-off.&nbsp; </p><p>What you are describing is a rotation.&nbsp; A missile, like an aircraft can rotate in three axes -- pitch, yaw and roll.&nbsp; The distinction between pitch and yaw for a cylindrical missile is a bit artificial, and this is one of them.&nbsp; Rotation about the long axis of the rocket is roll.&nbsp; In an airplane flying level, pitch is up and down about the axis through the wings, yaw is side to side about and axis that is vertical with respect to the fuselage, and roll is rotation about the long axis.</p><p>What I saw on the video seemed to be a little bit of roll being compensated by a roll control system, presumably from the second stage cold gas roll control system.&nbsp; I did not see any significant pitch or yaw and I did not see any rapid movements of the plume, which would have been indicative of control action in the pitch or yaw planes.&nbsp; I did not see anything of major concern until the staging event, recontact, and failure.</p><p>I also head a bunch of sound that I suspect was dubbed in.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[spacy600]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>No, I can't.&nbsp; There&nbsp; have been tremendous advances in engineering capability since those early days of rocketry.&nbsp; We now have readily available finite element analysis, advanced control theory, sophisticated 3 and 6 degree of freedom trajectory codes, advanced computational fluid dynamics codes, materials that were unheard of in the early days, many lessons learned from mistakes made in that era, etc.&nbsp; But most importantly there is an understanding of the engineering and review steps that can be applied to design a rocket so as incorporate all of these advances&nbsp; and not duplicat past failures.&nbsp;&nbsp;Space-X has demonstrated either total disregard or total ignorance towards these advances and the result is a thoroughly amateurish approach to rocket development.&nbsp; There is no excuse for having a failure as the result of a totally predictable series of events.&nbsp; If you can't avoid the obvious failure modes, you have no chance of avoiding the subtle ones.Not learning from mistakes made in the&nbsp; past is a mark of incompetence.&nbsp; There is no good excuse for reverting to the design practices of 50 or more years ago and ignoring all the benefits that ought to be available from the mistakes that others have made.&nbsp; If commercial space enterprises are ever to make a real go of it, they need to benefit from the past and not recreate it.&nbsp; Space-X is setting a very bad example.&nbsp;&nbsp;And it is the approach that results in these failures that is the real problem, more so than the failures themselves.&nbsp; In the case of Space-X the process is the problemIf Hyundai had started out building model Ts would you "cut them some slack"?&nbsp; <br /> Posted by DrRocket</DIV></p><p>&nbsp;</p><p>&nbsp;Are these past lessons learned trade secerts of the company, or orginization?</p><p>Or did they pass into "common knowledge" of industry?</p><p>&nbsp;</p><p>I agree ther have been great leaps of knowledge and understanding since the begining of this industry.&nbsp;</p>

 

[spacy600]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>No, I can't.&nbsp; There&nbsp; have been tremendous advances in engineering capability since those early days of rocketry.&nbsp; We now have readily available finite element analysis, advanced control theory, sophisticated 3 and 6 degree of freedom trajectory codes, advanced computational fluid dynamics codes, materials that were unheard of in the early days, many lessons learned from mistakes made in that era, etc.&nbsp; But most importantly there is an understanding of the engineering and review steps that can be applied to design a rocket so as incorporate all of these advances&nbsp; and not duplicat past failures.&nbsp;&nbsp;Space-X has demonstrated either total disregard or total ignorance towards these advances and the result is a thoroughly amateurish approach to rocket development.&nbsp; There is no excuse for having a failure as the result of a totally predictable series of events.&nbsp; If you can't avoid the obvious failure modes, you have no chance of avoiding the subtle ones.Not learning from mistakes made in the&nbsp; past is a mark of incompetence.&nbsp; There is no good excuse for reverting to the design practices of 50 or more years ago and ignoring all the benefits that ought to be available from the mistakes that others have made.&nbsp; If commercial space enterprises are ever to make a real go of it, they need to benefit from the past and not recreate it.&nbsp; Space-X is setting a very bad example.&nbsp;&nbsp;And it is the approach that results in these failures that is the real problem, more so than the failures themselves.&nbsp; In the case of Space-X the process is the problemIf Hyundai had started out building model Ts would you "cut them some slack"?&nbsp; <br /> Posted by DrRocket</DIV></p><p>&nbsp;</p><p>&nbsp;Are these past lessons learned trade secerts of the company, or orginization?</p><p>Or did they pass into "common knowledge" of industry?</p><p>&nbsp;</p><p>I agree ther have been great leaps of knowledge and understanding since the begining of this industry.&nbsp;</p>

 

[job1207]

We don't have long to wait, so I am willing to let them work out the kinks before condemning them, as if it mattered anyway. lol

 

[job1207]

We don't have long to wait, so I am willing to let them work out the kinks before condemning them, as if it mattered anyway. lol

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;&nbsp;Are these past lessons learned trade secerts of the company, or orginization?Or did they pass into "common knowledge" of industry?&nbsp;I agree ther have been great leaps of knowledge and understanding since the begining of this industry.&nbsp; <br />Posted by spacy600</DIV></p><p>Not trade secrets.&nbsp; They are widely known, by many people and organizations,&nbsp; Mistakes made by one program are known and the lessons applied in other programs across company and government organizational lines.&nbsp; </p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;&nbsp;Are these past lessons learned trade secerts of the company, or orginization?Or did they pass into "common knowledge" of industry?&nbsp;I agree ther have been great leaps of knowledge and understanding since the begining of this industry.&nbsp; <br />Posted by spacy600</DIV></p><p>Not trade secrets.&nbsp; They are widely known, by many people and organizations,&nbsp; Mistakes made by one program are known and the lessons applied in other programs across company and government organizational lines.&nbsp; </p> <div class="Discussion_UserSignature"> </div>

 

[aaron38]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If Hyundai had started out building model Ts would you "cut them some slack"?&nbsp; <br />Posted by DrRocket</DIV></p><p>SpaceX isn't building a model T, the Merlin is very high performance for a startup.&nbsp; But Hyundai was given slack on reliability in exchange for low cost.&nbsp; That's what SpaceX is doing.&nbsp; They are building high performance at lower cost.</p><p>&nbsp;Like it or not, if space travel is to become routine, the industry needs to become much more like the auto and airline industries.&nbsp; When a plane crashes, the next one takes off anyway.&nbsp; When a Hyundai has a mechanical failure and kills someone, yes there's a recall, but all the Hyundais keep on driving around in the meantime.</p><p>So I do cut them slack so that they can get a low cost product out there.&nbsp; Because we don't stop flying 747s when one crashes, and we shouldn't stop flying rockets when one crashes either.&nbsp; Rockets need to move into a realm where they&nbsp;keep flying as the bugs are worked out, instead of a failure being a national tragedy that causes a 3 year halt.&nbsp; But we need low cost for that, and it has to be private, not tax dollar funded so John Q. Public doesn't whine about his money being spent on space.</p>

 

[aaron38]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If Hyundai had started out building model Ts would you "cut them some slack"?&nbsp; <br />Posted by DrRocket</DIV></p><p>SpaceX isn't building a model T, the Merlin is very high performance for a startup.&nbsp; But Hyundai was given slack on reliability in exchange for low cost.&nbsp; That's what SpaceX is doing.&nbsp; They are building high performance at lower cost.</p><p>&nbsp;Like it or not, if space travel is to become routine, the industry needs to become much more like the auto and airline industries.&nbsp; When a plane crashes, the next one takes off anyway.&nbsp; When a Hyundai has a mechanical failure and kills someone, yes there's a recall, but all the Hyundais keep on driving around in the meantime.</p><p>So I do cut them slack so that they can get a low cost product out there.&nbsp; Because we don't stop flying 747s when one crashes, and we shouldn't stop flying rockets when one crashes either.&nbsp; Rockets need to move into a realm where they&nbsp;keep flying as the bugs are worked out, instead of a failure being a national tragedy that causes a 3 year halt.&nbsp; But we need low cost for that, and it has to be private, not tax dollar funded so John Q. Public doesn't whine about his money being spent on space.</p>

 

[StrandedonEarthsince1970]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>SpaceX isn't building a model T, the Merlin is very high performance for a startup.&nbsp; But Hyundai was given slack on reliability in exchange for low cost.&nbsp; That's what SpaceX is doing.&nbsp; They are building high performance at lower cost.&nbsp;Like it or not, if space travel is to become routine, the industry needs to become much more like the auto and airline industries.&nbsp; When a plane crashes, the next one takes off anyway.&nbsp; When a Hyundai has a mechanical failure and kills someone, yes there's a recall, but all the Hyundais keep on driving around in the meantime.So I do cut them slack so that they can get a low cost product out there.&nbsp; Because we don't stop flying 747s when one crashes, and we shouldn't stop flying rockets when one crashes either.&nbsp; Rockets need to move into a realm where they&nbsp;keep flying as the bugs are worked out, instead of a failure being a national tragedy that causes a 3 year halt.&nbsp; But we need low cost for that, and it has to be private, not tax dollar funded so John Q. Public doesn't whine about his money being spent on space. <br /> Posted by aaron38</DIV></p><p>&nbsp;</p><p>I can't help but point out that if the first three 747 flights ended in crashes, then many would hesitate to step aboard the fourth flight.</p><p>&nbsp;</p><p>OTOH, it's just hardware going aboard, not people, so crashing a few to get it right is not a huge deal. It is, after all "only" money.</p> <div class="Discussion_UserSignature"> <p> </p><p><em><strong>Now where on Earth did I park my UFO?</strong></em></p> </div>

 

[StrandedonEarthsince1970]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>SpaceX isn't building a model T, the Merlin is very high performance for a startup.&nbsp; But Hyundai was given slack on reliability in exchange for low cost.&nbsp; That's what SpaceX is doing.&nbsp; They are building high performance at lower cost.&nbsp;Like it or not, if space travel is to become routine, the industry needs to become much more like the auto and airline industries.&nbsp; When a plane crashes, the next one takes off anyway.&nbsp; When a Hyundai has a mechanical failure and kills someone, yes there's a recall, but all the Hyundais keep on driving around in the meantime.So I do cut them slack so that they can get a low cost product out there.&nbsp; Because we don't stop flying 747s when one crashes, and we shouldn't stop flying rockets when one crashes either.&nbsp; Rockets need to move into a realm where they&nbsp;keep flying as the bugs are worked out, instead of a failure being a national tragedy that causes a 3 year halt.&nbsp; But we need low cost for that, and it has to be private, not tax dollar funded so John Q. Public doesn't whine about his money being spent on space. <br /> Posted by aaron38</DIV></p><p>&nbsp;</p><p>I can't help but point out that if the first three 747 flights ended in crashes, then many would hesitate to step aboard the fourth flight.</p><p>&nbsp;</p><p>OTOH, it's just hardware going aboard, not people, so crashing a few to get it right is not a huge deal. It is, after all "only" money.</p> <div class="Discussion_UserSignature"> <p> </p><p><em><strong>Now where on Earth did I park my UFO?</strong></em></p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>SpaceX isn't building a model T, the Merlin is very high performance for a startup.&nbsp; But Hyundai was given slack on reliability in exchange for low cost.&nbsp; That's what SpaceX is doing.&nbsp; They are building high performance at lower cost.&nbsp;Like it or not, if space travel is to become routine, the industry needs to become much more like the auto and airline industries.&nbsp; When a plane crashes, the next one takes off anyway.&nbsp; When a Hyundai has a mechanical failure and kills someone, yes there's a recall, but all the Hyundais keep on driving around in the meantime.So I do cut them slack so that they can get a low cost product out there.&nbsp; Because we don't stop flying 747s when one crashes, and we shouldn't stop flying rockets when one crashes either.&nbsp; Rockets need to move into a realm where they&nbsp;keep flying as the bugs are worked out, instead of a failure being a national tragedy that causes a 3 year halt.&nbsp; But we need low cost for that, and it has to be private, not tax dollar funded so John Q. Public doesn't whine about his money being spent on space. <br />Posted by aaron38</DIV></p><p>The cost of a rocket is a relatively small piece of the launch costs for sophisticated satellites.&nbsp; The satellite typically costs more than the launch and returns a value much greater than its cost.&nbsp; Launch insurance is a big piece of the cost.&nbsp; A cheap unreliable rocket is not economical.&nbsp; An expensive and highly reliable launch vehicle has lower cost to the customer.</p><p>I am happy to hear that you know what Space X is doing.&nbsp; They don't appear to know what they are doing.&nbsp; It is good that someone has figured it out.</p><p>We are long past the days where rockets either need or should be flying while the bugs are worked out.&nbsp; That ought to be done on the ground. And repeating past mistakes is simply not acceptable practice any longer.&nbsp; We don't accept a bunch of failures in the development of airplanes any more either.&nbsp; The kinks are worked out on the ground with computer models.</p><p>There is a big difference between flying an airplane when one of a large and proven fleet crashes and flying a developmental rocket to diagnose and fix inherent design problems.&nbsp; The very fact that these problems have repeatedly shown up only in flights is proof that the engineers at Space X do not have an adequate understanding of their own design.&nbsp; That is the real problem, more so than the simple fact of the failures.&nbsp; Flying to find failures is an amateur approach.&nbsp; Competent engineering organizations do not tolerate such nonsense.&nbsp; The more so since the problems involved have been seen before and are predictable and avoidable.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>SpaceX isn't building a model T, the Merlin is very high performance for a startup.&nbsp; But Hyundai was given slack on reliability in exchange for low cost.&nbsp; That's what SpaceX is doing.&nbsp; They are building high performance at lower cost.&nbsp;Like it or not, if space travel is to become routine, the industry needs to become much more like the auto and airline industries.&nbsp; When a plane crashes, the next one takes off anyway.&nbsp; When a Hyundai has a mechanical failure and kills someone, yes there's a recall, but all the Hyundais keep on driving around in the meantime.So I do cut them slack so that they can get a low cost product out there.&nbsp; Because we don't stop flying 747s when one crashes, and we shouldn't stop flying rockets when one crashes either.&nbsp; Rockets need to move into a realm where they&nbsp;keep flying as the bugs are worked out, instead of a failure being a national tragedy that causes a 3 year halt.&nbsp; But we need low cost for that, and it has to be private, not tax dollar funded so John Q. Public doesn't whine about his money being spent on space. <br />Posted by aaron38</DIV></p><p>The cost of a rocket is a relatively small piece of the launch costs for sophisticated satellites.&nbsp; The satellite typically costs more than the launch and returns a value much greater than its cost.&nbsp; Launch insurance is a big piece of the cost.&nbsp; A cheap unreliable rocket is not economical.&nbsp; An expensive and highly reliable launch vehicle has lower cost to the customer.</p><p>I am happy to hear that you know what Space X is doing.&nbsp; They don't appear to know what they are doing.&nbsp; It is good that someone has figured it out.</p><p>We are long past the days where rockets either need or should be flying while the bugs are worked out.&nbsp; That ought to be done on the ground. And repeating past mistakes is simply not acceptable practice any longer.&nbsp; We don't accept a bunch of failures in the development of airplanes any more either.&nbsp; The kinks are worked out on the ground with computer models.</p><p>There is a big difference between flying an airplane when one of a large and proven fleet crashes and flying a developmental rocket to diagnose and fix inherent design problems.&nbsp; The very fact that these problems have repeatedly shown up only in flights is proof that the engineers at Space X do not have an adequate understanding of their own design.&nbsp; That is the real problem, more so than the simple fact of the failures.&nbsp; Flying to find failures is an amateur approach.&nbsp; Competent engineering organizations do not tolerate such nonsense.&nbsp; The more so since the problems involved have been seen before and are predictable and avoidable.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;I think several Russian vaunch vehicles such as the Soyuz booster have a open truss between the first and secon stage. <br />Posted by shuttle_guy</DIV></p><p>I checked my references and you are correct.&nbsp; The Soyuz does use such a truss.</p><p>I am not a great fan of Russian design&nbsp;philosophy, and I would not do that, but apparently they can handle the aerodynamics and they do.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;I think several Russian vaunch vehicles such as the Soyuz booster have a open truss between the first and secon stage. <br />Posted by shuttle_guy</DIV></p><p>I checked my references and you are correct.&nbsp; The Soyuz does use such a truss.</p><p>I am not a great fan of Russian design&nbsp;philosophy, and I would not do that, but apparently they can handle the aerodynamics and they do.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

 

[aaron38]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I am happy to hear that you know what Space X is doing.&nbsp; They don't appear to know what they are doing.&nbsp; It is good that someone has figured it out.</DIV><br /><br />All I'm saying is, everyone makes mistakes, and I'm not going to hold that against them.&nbsp; If we hold to a philosophy that space flight has to be perfect each and every time and a failure is intollerable....&nbsp; Well, be prepared to sit on this rock a very long time.</p>

 

[aaron38]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I am happy to hear that you know what Space X is doing.&nbsp; They don't appear to know what they are doing.&nbsp; It is good that someone has figured it out.</DIV><br /><br />All I'm saying is, everyone makes mistakes, and I'm not going to hold that against them.&nbsp; If we hold to a philosophy that space flight has to be perfect each and every time and a failure is intollerable....&nbsp; Well, be prepared to sit on this rock a very long time.</p>