They have had two failures: https://en.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_He...
Out of 25 launches is that a safe enough success rate?
The second failure was a second stage exploding. Had the payload been a crewed Dragon V2, those inside would have survived. Even without a launch escape system, the Dragon V1 was fine[2]:
> The Dragon CRS-7 capsule was ejected from the exploding launch vehicle and continued transmitting data until impact with the ocean. SpaceX officials stated that it could have been recovered if the parachutes deployed, however the software in the capsule did not include any provisions for parachute deployment in this situation.
Overall, it's a much safer design than the Shuttle. The crew vehicle is on top of the stack instead of along side it. If anything goes wrong, the capsule can GTFO and land with parachutes.
That seems like a pretty significant oversight?
(I'm not sure if there was a reason or not)
> The software in this cargo version of Dragon (Dragon 1), Musk explained, is inert on ascent and was not programmed to release the parachute in the event of a failure. Software in the version of Dragon under development for taking people into space (Dragon 2 or Crew Dragon) is programmed to do just that.
While it sounds like simple thing, remote control of the 'chutes would add significant complexity and cost.
1. http://www.spacepolicyonline.com/news/failed-strut-likely-ca...
http://motherboard.vice.com/read/john-aaron-apollo-12-curios...
I guess we can forgive Bean for frying the color TV camera, then.
Net result, failed launches are not really worth trying to recover unless it's people. Though, deploying parachutes may have marginally reduced the risks to a passing boat.
Didn't it fall in the range safety exclusion zone, which ships were warned away from?
After having learned in real world conditions that it can handle those sorts they figured, what the heck... might as well add it.
The crewed Dragon (Dragon 2) uses powered thrusters to push itself away from a failing rocket.
Redstone had a success rate of 5/6. [1] Atlas had a success rate of 13/24. [2]
It was certainly a different time, but spaceflight has always been really risky. There has also always been more attention paid to human rated flights during the manufacturing & testing process. I also imagine SpaceX will not be doing first flights of new Falcon 9 variations with humans aboard.
That's not to say it is low risk, but 23/25 considering these are unmanned and largely R&D flights is not bad.
[1] https://en.wikipedia.org/wiki/Mercury-Redstone_Launch_Vehicl...
[2] https://en.wikipedia.org/wiki/SM-65_Atlas#Atlas-D_deployment
The day before Walter Schirra launched there was an Atlas D failure.
Two months before Gordon Cooper launched there was an Atlas D failure.
What I don't know is how much they were pushing the limits on the other tests vs the manned flights, or how much more QA they were putting into the manned rockets, but it is certainly not the case that NASA only flew on rockets with high success rates at that time.
[1] https://en.wikipedia.org/wiki/List_of_Atlas_launches_(1960%E...
[2] https://en.wikipedia.org/wiki/List_of_Atlas_launches_(1957%E...
The catastrophic failure is obviously a problem. However, for a manned mission, there is an abort system which is supposed to save the lives of the crew in an event like this. This is not like the Shuttle where if anything goes wrong on launch, everybody is doomed.
To state it more precisely, out of 25 launches, there has been one problem which wouldn't have been a threat, one catastrophic failure which would be survivable, and zero failures which would have killed anybody if they had been manned.
While it is certainly great to aim for 100% success, it's helpful to remember that astronauts are willing to take measured risks in order to perform their missions, and that we must select rockets/etc from the options available, not from the options we might wish to have.
0: https://en.wikipedia.org/wiki/List_of_Space_Shuttle_missions
People aren't arguing the merits of success they just want to use the same rules to talk about nasa and spacex
[1] http://www.amazon.com/Development-Shuttle-1972-1981-History-...
1: http://www.popularmechanics.com/space/a6611/us-space-shuttle...
There was a time sailing across the Atlantic was dangerous.
So the goal for rockets - for now - could be to become as safe to ride as airplanes are. 100% safety is unobtainable, so shouldn't be a requirement.
The energy an orbital rocket packs is significantly more than the full fuel load of a 747. The required performance is also much higher. Tolerances are much lower (because of the performance).
It'll be quite some time until they get to 747 levels. A worthy goal would be to become as cheap as a 747 at a reasonable safety level. That would be massively disruptive.
If you could build a spacecraft launch system with the weight budget of a commercial airliner, you could get that reliability. The fuel fraction for the Space Shuttle was about 85%; everything else, structure, engines, equipment, and payload, comes out of the remaining 15%. For an airliner, 60% of the mass is non-fuel. Spacecraft are weight-reduced too far to get aircraft reliability. They're just too fragile. Read NASA's "The Tyranny of the Rocket Equation".[1]
Space travel with chemical fuels out of Earth's gravity well is just barely possible at all. Chemical fuels just don't have the energy density to do the job well. It's necessary to launch huge booster stacks to put a dinky payload in orbit. That's why, after 50 years, space flight hasn't progressed all that much.
Without a denser power source, it will never get much better.
[1] http://www.nasa.gov/mission_pages/station/expeditions/expedi...
I want SpaceX to succeed as much as anyone (probably more since I work there), but one should not delude oneself into thinking that predictions are fact.
And if you want to consider the whole Saturn V STACK then you're going to have to consider counting Apollo 13 as a failure. The "payload" for Apollo is, in the end, really just the Command Module.
The whole point of doing testing with rockets is to find what you don't know, validate your assumptions... What you usually don't know is when a thing will fail - and you don't want to learn that in a real mission, so you push the test article to extreme. Another reason to do tests is something which should work - and shouldn't fail - but you can't test that without actually doing a flight test.
So, in my opinion, cherry picking test flights - where things fail routinely, otherwise why testing? - doesn't show you the designed - and updated, with test data - reliability of the system.
Regarding whole stack - I meant the whole thing which lifted off and the part of which reached low Earth orbit. That stack had the pulling safety tractor rocket. But frankly, if I'd consider Apollo-13 flight, I'd assume we have the case of mission abort in a later stage of flight, after which the existing measures were taken to bring back the craft safely. So mission was aborted - just as it would be if, say, Saturn-V grossly misbehaved on 30th second of flight - and the systems worked on safe return.
https://reason.com/archives/2012/01/26/how-much-is-an-astron...
Second, just because there are negative aspects in the world that cause loss of life, doesn't mean we shouldn't be doing everything we can to ensure a safe flight. This is unrelated to the cost aspect mentioned in my first point, but the average person living in the U.S.A is only living as comfortable as they are because modern civilization, for the most part, values safety quite high. It's a poor argument to say "Well X people died yesterday, so we shouldn't care so much about the 4 that might die in a launch".
That is irrelevant to the level safety precautions. Unless you were trying to argue that their costly training makes them worth more than other people. I hope that is not what you were arguing.
> doesn't mean we shouldn't be doing everything we can to ensure a safe flight
At some point you have to declare something 'safe enough' since 100% safety is an impossible perfection. Bicycles aren't 100% safe, but we don't go around insisting on multiple backup systems. Personally I do find it curious that the standard of safety for astronauts is so high. The cynic in me suggests its less out of concern for the astronauts and more to do with the publicity fallout that occurs after disasters and the damage to other assets. The optimist suggests its more a concern for all the ground crew and spectators who are also at risk. There is potential for a lot more than 4 casualties when you play with that much fire.
>That is irrelevant to the level safety precautions. Unless you were trying to argue that their costly training makes them worth more than other people. I hope that is not what you were arguing.
I believe GP was arguing about the "a dime a billion" part. They are not worth more than other people in the human sense, but that doesn't make them any more common. It's just the fact that there are very few people with such qualifications that negate the argument of "a dime a billion".
And I guess it's also true that not any of those billions could be trained to be an astronaut for a myriad of reasons.
This is less clear. Even more, the space tourism industry relies on that to be false. To an extent.
But I think there is (or at least will/should be) a difference between a trained astronaut and a space tourist.
I mean, being an astronaut is more than just going to outer space, isn't it? A space tourist might do a lot of the stuff that astronauts do, but I think there will still be a fundamental difference. Astronauts are there to do research, push the limits on human capabilities, etc.
After all that is settled, then the tourists can come.
I would imagine they are to the company that is launching them.
Right, but that doesn't mean we should follow that just because the ancestors did that?
On the opposite, I'd hope for astronaut-level safety precautions be spreading for the rest of society, so everybody could benefit.
"Thousands of people die in car accidents every year and..."
It's bizarre that anyone would find this type of comment insightful after all the times its been posted ad nauseam.