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The point I am making is that for some reason, the human race understood that fancy TV's were a good thing, and kept buying them by the million until their reliability was acceptable. The same is not true for spaceflight. You could make an argument that I'm being unrealistic expecting equivalent reliability in spaceflight, and if you look accept our current expenditure in spaceflight, that is true. However, what I'm really saying is that we aren't willing to invest to the point where we can attain high reliability. That last 5% really isn't that hard, especially when we're talking about the one thing that can guarantee the future of the human race.

We live on a planet that has suffered huge meteor impacts, ice ages, super volcanoes, and technological civilization can concievably be ended by these things, as well as world war, resource scarcity and disease. We're not making enough rockets (and achieve the associated reliabilty) to make the human race secure. That is why I am angry.

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The point I am making is that for some reason, the human race understood that fancy TV's were a good thing, and kept buying them by the million until their reliability was acceptable. The same is not true for spaceflight. You could make an argument that I'm being unrealistic expecting equivalent reliability in spaceflight, and if you look accept our current expenditure in spaceflight, that is true. However, what I'm really saying is that we aren't willing to invest to the point where we can attain high reliability. That last 5% really isn't that hard, especially when we're talking about the one thing that can guarantee the future of the human race.

We live on a planet that has suffered huge meteor impacts, ice ages, super volcanoes, and technological civilization can concievably be ended by these things, as well as world war, resource scarcity and disease. We're not making enough rockets (and achieve the associated reliabilty) to make the human race secure. That is why I am angry.

Clearly you've never worked in science, engineering, manufacturing, medicine or the service industry before. The consumer electronics example you cite is an especially bad one, starting with around 3-4% repair rate in the first year and increasing up to 15% in the 4th year. You don't even need to spend 5 minutes on Google to learn that.

Stop being angry and start finding sources before you make claims, please. Yes, the last 5% really, truly, absolutely is that hard, in every field. Everything else is wishful thinking of the uninformed.

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Clearly you've never worked in science, engineering, manufacturing, medicine or the service industry before. The consumer electronics example you cite is an especially bad one, starting with around 3-4% repair rate in the first year and increasing up to 15% in the 4th year. You don't even need to spend 5 minutes on Google to learn that.

Stop being angry and start finding sources before you make claims, please. Yes, the last 5% really, truly, absolutely is that hard, in every field. Everything else is wishful thinking of the uninformed.

Launch vehicle reliability varies but typical figures fall between 90-98%. Are you seriously telling me that I have that likelyhood of encountering a serious failure if I pick up a smartphone today?

Oh, and before you accuse me of equating smartphones with rockets, I am well aware that one is more complex than the other. Please consider the point I made in a previous post about the investment we're making in rocketry. That is what I'm angry about. We may not get to be 100% reliable, but we can do better, much much better. We just need to wake up to the situation now.

Edited by DunaRocketeer
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The point I am making is that for some reason, the human race understood that fancy TV's were a good thing, and kept buying them by the million until their reliability was acceptable. The same is not true for spaceflight. You could make an argument that I'm being unrealistic expecting equivalent reliability in spaceflight, and if you look accept our current expenditure in spaceflight, that is true. However, what I'm really saying is that we aren't willing to invest to the point where we can attain high reliability. That last 5% really isn't that hard, especially when we're talking about the one thing that can guarantee the future of the human race.

We live on a planet that has suffered huge meteor impacts, ice ages, super volcanoes, and technological civilization can concievably be ended by these things, as well as world war, resource scarcity and disease. We're not making enough rockets (and achieve the associated reliabilty) to make the human race secure. That is why I am angry.

Bit dramatic aren't we?

I'm all for space exploration and expanding our knowledge and list of places we've been to, but it has to be understood that space as a means of survival for the human species is a super long term project, so expansive in terms of the required technology, resources and manpower that it becomes as meaningless a mission as 'curing all disease'. Let's get the basics right first, okay, and work out the issue(s) with the Falcon 9 in the appropriate amount of time.

We all want to see more space exploration, but you honestly scare off willing contributors with hysterical talk of super volcanoes and meteor impacts that none of us are likely to see in our lives. In fact, synthetic foods (lessen dependence on traditional, water-inefficient agriculture) and advanced detection equipment (to spot asteroids, give us clues on how the volcanoes of the world behave etc) are probably better short term investments to counter those threats...

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Ever heard blown-out phones ? Or when people complain their phones have a shorter battery life despite normal usage ? What's that ?

If I were to say, the reliability of Falcon 9 is 16/17 = 94%. Close to 95% isn't ?

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Aanker, it most definitely isn't hysterical to talk about meteor impacts. You are of course correct in that we aren't likely to see one in our life times, but it will happen someday, and there really is no better countermeasure to it than have humanity as a multiplanetary species. If that scares away contributors, that is their problem.

It's look very Kerbal:D

Oh ffs I just give up.

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Ever heard blown-out phones ? Or when people complain their phones have a shorter battery life despite normal usage ? What's that ?

If I were to say, the reliability of Falcon 9 is 16/17 = 94%. Close to 95% isn't ?

it is actually 17,5/19. Falcon 9 v1.0 had 5 launches of which 4 were successful with one where secondary cargo was lost due to engine failure on 1st stage so I count that as 0,5. F9 v1.1 has as of today 13/14 success launches. That is still 92% success rate which in my opinion is quite satisfactory and with further refinements and more experience can get even better.

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it is actually 17,5/19. Falcon 9 v1.0 had 5 launches of which 4 were successful with one where secondary cargo was lost due to engine failure on 1st stage so I count that as 0,5. F9 v1.1 has as of today 13/14 success launches. That is still 92% success rate which in my opinion is quite satisfactory and with further refinements and more experience can get even better.

There's a change in design, basically you can't combine them.

My suggestion is to tighten (or increase) QC for the rocket and the rocket parts. Say, if every process is bound to 95% success, then an additional process (which the rule apply) will at least remove 95% from that 5% - leaving you with 0.25% chance of going wrong. Hope SpaceX and everyone else is learning out from this - maybe the shuttle did the same (24/25 success rate, then increased to 109/110 success rate).

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The point I am making is that for some reason, the human race understood that fancy TV's were a good thing, and kept buying them by the million until their reliability was acceptable. The same is not true for spaceflight. You could make an argument that I'm being unrealistic expecting equivalent reliability in spaceflight, and if you look accept our current expenditure in spaceflight, that is true. However, what I'm really saying is that we aren't willing to invest to the point where we can attain high reliability. That last 5% really isn't that hard, especially when we're talking about the one thing that can guarantee the future of the human race.

We live on a planet that has suffered huge meteor impacts, ice ages, super volcanoes, and technological civilization can concievably be ended by these things, as well as world war, resource scarcity and disease. We're not making enough rockets (and achieve the associated reliabilty) to make the human race secure. That is why I am angry.

Its an major diference between an mass produced product and something who is made in low volumes, demanding extreme performance and most fails are catastrophically.

TV's has another problem then production of both lcd and oled screen started most screens did not work, solution was to double the price and try to tweak the production to reduce fails.

Solid state electronic mostly work or not. Cars is an better example, cars was a lot less reliable earlier, 50 years ago 100.000 km was expected life for an engine.

Now you would not get reliable car engines if you had not worked a lot with them for 100 years. Same with planes who is far closer to rockets, they was very dangerous in the beginning, then they became safer and safer because of more experience.

The only way to get experience is to practice.

Rockets are harder than planes, performance demands are much higher and the volume is much lower so you don't learn as much.

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Launch vehicle reliability varies but typical figures fall between 90-98%. Are you seriously telling me that I have that likelyhood of encountering a serious failure if I pick up a smartphone today?

Some devices are almost perfect and the chance of it failing could be a percentage smaller than 1.

But there are enough devices, look at the Xbox 360 and PS4, which have a high percentage of failing.

Some phones fail if you drop them others can be run over by a truck and still work like intended.

Still, these things don't have to endure internal and external pressure, extreme temperatures, etc. etc.

The good thing is that the F9 is not mass mass produced yet.

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it is actually 17,5/19. Falcon 9 v1.0 had 5 launches of which 4 were successful with one where secondary cargo was lost due to engine failure on 1st stage so I count that as 0,5. F9 v1.1 has as of today 13/14 success launches. That is still 92% success rate which in my opinion is quite satisfactory and with further refinements and more experience can get even better.

Rocket reliability is calculated slightly differently, actually, by a first level Bayesian estimate of mean predicted probability of success for next launch attempt (k+1)/(n+2) where k is the number of successful events and n is the number of trials. Yes, that was a quote I fished elsewhere :P

For the Falcon 9 prior to yesterday's launch, the formula would have returned the following:

- 95.00%, if all Falcon 9 flights are counted with regards to primary mission successes;

- 92.50%, if all Falcon 9 flights are counted with the last v1.0 flight being a "half success";

- 93.33%, if only Falcon 9 v1.1 launches are counted.

For the Falcon 9 after yesterday's launch failure, the formula returns the following:

- 90.48%, if all Falcon 9 flights are counted with regards to primary mission successes;

- 88.09%, if all Falcon 9 flights are counted with the last v1.0 flight being a "half success";

- 87.50%, if only Falcon 9 v1.1 launches are counted.

Again, these numbers mean "mean predicted probability that the next launch will be successful".

EDIT: The idea behind this approach is that it returns a valid result for a rocket that has never flown before. That result is exactly 50/50, as it should be. ;)

Edited by Streetwind
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Ever heard blown-out phones ? Or when people complain their phones have a shorter battery life despite normal usage ? What's that ?

If I were to say, the reliability of Falcon 9 is 16/17 = 94%. Close to 95% isn't ?

That is awesome reliability! I don't understand what you're mad at dunarocketeer.

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Launch of CRS-7 recorded in infrared:

https://www.youtube.com/watch?v=SP3eUoQvQyY

That's interesting, you see a small flash at 2.24, but then nothing unusual until it explodes properly a few seconds later. Maybe reinforces the idea that it's cold LOX forming the initial cloud which you can't see in infrared, and it doesn't actually explode until the amazingly robust first stage goes pop. It's quite impressive how long the first stage keeps going straight considering what's happened to the second stage and dragon getting thrown free.

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Alright, I've got a theory for you all to pick at given a few bits of info.

So, Musk states a couple of things.

First: The incident was likely an over pressure event.

Second: The possible cause seems counter intuitive.

External to musk, an important item: The incident happened a few seconds past Max-Q (the point of highest dynamic pressure on the vehicle).

So, here is my theory: At or around the point of Max-Q one of the valves (be it a fill valve, or an over pressure release valve for the 2nd stage LOX tank) burst into an open configuration. In some strange coincidence of positioning and movement, this caused air to force its way into the tank, the over pressure event.

The valve in question is my guess because of the statement about the possible cause being counter intuitive.

Probably not too likely, but just something I came up with this morning.

Also, I just learned that yesterday (day of launch) was Musk's 44th birthday. :(

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The main goal is achieve reusability, once spacex achieve that, then the ratio of possible failure will drop considerably.

Is like I said before, you will feel more secure flying in a 747 that fly often, or in a new 747 which never was in the air?

That is the thing that happen with rockets right now, there is not way to fully tested them (also is very expensive even try to test them to reduce chances of failure), until you dont press the launch button nobody knows.

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That's interesting, you see a small flash at 2.24, but then nothing unusual until it explodes properly a few seconds later. Maybe reinforces the idea that it's cold LOX forming the initial cloud which you can't see in infrared, and it doesn't actually explode until the amazingly robust first stage goes pop. It's quite impressive how long the first stage keeps going straight considering what's happened to the second stage and dragon getting thrown free.

I'm betting the second explosion is range safety charges... Uniform flames.

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I guess the 1st stage is so powerful that it can't be easily influenced by the stuff on top of it.

Maybe reinforces the idea that it's cold LOX forming the initial cloud

The leaking LOX theory is quite popular here. Assuming it is true what caused the LOX tank to break? The rocket passed the max-Q mark so the reason couldn't be aerodynamic stress. Was it the high TWR of the nearly empty 1st stage crushing struts in the 2nd stage? Was it the preparations for 2nd stage activation? Did the payload come loose as some people in this forum think? Mechanical failure? Software problem?

From what I can see in the videos first there's a cloud coming from the top of the 1st stage or from the 2nd stage. Then the second stage seemed to receive a lot of damage, the Dragon capsule came loose. Then the cloud seems to explode and shortly after that the whole rocket was kerbalized by aerodynamic forces.

I can't image what caused the tank to break which led to this tragic outcome.

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The first stage's nine Merlin 1D engines keep firing at least 8 seconds after the first signs of structural damage/collapse. I know that, whilst most rockets have an onboard computer at the top that controls all the stages underneath, the F9 also has a computer inside its first stage, so that it can reenter and land on the ASDS. However, shouldn't the second stage computer have informed the first stage one about the failure, so that it would cut its engines? Could this be a sign that the two computers weren't communicating with each other?

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The first stage's nine Merlin 1D engines keep firing at least 8 seconds after the first signs of structural damage/collapse. I know that, whilst most rockets have an onboard computer at the top that controls all the stages underneath, the F9 also has a computer inside its first stage, so that it can reenter and land on the ASDS. However, shouldn't the second stage computer have informed the first stage one about the failure, so that it would cut its engines? Could this be a sign that the two computers weren't communicating with each other?

They have to be programmed to handle the event type too.

First stage return mode don't activate until after separation to avoid generate issues with the launch in any case so my guess is that its controlled from second stage.

Where is lite need to do much programing around an second stage fail as you will simply loose the rocket in any setting.

Only thing you might do is to try to land the dragon to save the pressurized cargo.

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Not saying it happened, but what would one see in a thermal image if an anti-missile laser system were targeting during the boost trajectory? At that altitude, would there be any florescence or scatter of beam energy evident?

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Would anything have been changed if the two computers had been communicating?

They probably do need to reliably signal a few things to each other, but some of them would be events that could also be detected by instruments such as accelerometers.

Full communication could be a lot more complicated than a wire carrying a logical 1 signal from the stage 1 PSU, which breaks on separation. It's more complicated than a second wire carrying an OK from the stage 1 controller. But the more complicated, the more bugs there might be.

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