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Airliners are the safest form of transport ever devised. You’re safer in an airliner than you are in the shower. Space travel is one of the most dangerous form

Airliners are the safest form of transport ever devised. You’re safer in an airliner than you are in the shower. Space travel is one of the most dangerous forms of transport ever devised. Even the most insane, wildly optimistic estimates for the safety of the Shuttle were orders of magnitude more dangerous than an airliner. Comparing the two does not make sense. If airliners are your standard of safety for space travel, you might as well take a shortcut and just say “don’t launch humans into space.”

PhantomGremlin 7y ago
Comparing the two does not make sense. If airliners are your standard of safety for space travel, you might as well take a shortcut and just say “don’t launch humans into space.” It most certainly makes sense. A lot of sense. The Dragon capsule spectacularly blew itself to smithereens. Now is not the time to bring out some duct tape and baling wire to slap the thing back together so that it can attempt to fly astronauts into space before the end of the year. Now is the time for careful and considered testing. Not rushing. This thing needs to be safe. I can guarantee you one thing. If American astronauts die this year because of inadequate testing, that will be the last time you see American astronauts being launched into space on a NASA sponsored platform. If Americans die because this was rushed, you can kiss NASA's manned space efforts goodbye. We'll pay the Russians what it takes to keep going to ISS. And when ISS ends, NASA will be out of the manned space flight business. The operative word going forward will be "robotics".
- yellow_postit 7y ago
  What leads you to believe this is being rushed?
- lutorm 7y ago
  Space travel is not "safe", period. If you decide to go into space, you should be aware that you're exposing yourself to significant risk. The question is: what risk are you willing to accept? You may still be right about your prediction, though. But that just says something about people having unrealistic expectations.
- FeepingCreature 7y ago
  > If American astronauts die this year because of inadequate testing, that will be the last time you see American astronauts being launched into space on a NASA sponsored platform. And that's why the US shut down the manned space program after Challenger. > If Americans die because this was rushed, you can kiss NASA's manned space efforts goodbye. We'll pay the Russians what it takes to keep going to ISS. The lack of recent fatalities with the Soyuz does not mean the Soyuz is "safe". 141 safe launches just implies that the probability of success is p^141=0.5 (since I have no idea how likely this outcome was, I default to 50/50), so 99.5%. (edit: 99.3% with Laplace's rule.) That's very good, but it's also very very far from the safety record of airplanes.
- mikeash 7y ago
  Just say “don’t send humans into space.” It’ll save you a lot of typing and you end up in the same place.
bscphil 7y ago
You're right on the basic idea here, but may be wrong on the specific claim. Basically, trains and buses are also very safe, possibly even safer. In the US (important qualifier), commercial air travel sees a fatality rate of 0.07 per billion passenger miles. Also (important qualifier), that number excludes acts of suicide and terrorism. Buses see a fatality rate of 0.11 per billion passenger miles. Trains see a rate of 0.15 per billion passenger miles (not including fatalities of non-passengers). Both of those modes of transportation compare favorably with air travel. If you consider a worldwide perspective (in which pilots are on average less well trained), and include the effects of hijacked planes, it's possible one of the two might even beat it. (I'm not disagreeing with you that on a per-mile basis, air travel is very safe. I just think the specific numbers here are interesting. Also worth pointing out that for trips less than a few hundred miles, other modes are probably safer. If rail was used more for long distance travel, it would probably improve its safety record by this metric. And air travel is pretty terrible for the environment as well.) Source: https://journalistsresource.org/studies/environment/transportation/comparing-fatality-risks-united-states-transportation-across-modes-time/ https://journalistsresource.org/studies/environment/transpor...
- Voloskaya 7y ago
  Why spend so much energy arguing on something that wasn't even the point OP was making?
  - gdy 7y ago
    Because it's fun.
- mikeash 7y ago
  I think those numbers are old, as you can tell from the "excludes terrorism" qualifier. If you look at, say, the last decade, terrorism doesn't make any difference. This isn't entirely arbitrary: air travel has gotten a lot safer lately. Doing the math using the data from https://www.bts.gov/content/transportation-fatalities-mode https://www.bts.gov/content/transportation-fatalities-mode and https://www.bts.gov/content/us-passenger-miles https://www.bts.gov/content/us-passenger-miles, I come up with 6,059 billion airline passenger-miles for the decade ending in 2017 (the last year provided there) and 66 fatalities, for a rate of about 0.01 per billion passenger miles. In the same period, railroads did about 176 billion passenger miles with 94 fatalities, for a rate of about 0.53. Buses did 3,234 billion passenger miles with 486 fatalities, for a rate of 0.15. The numbers vary in other countries, but I suspect they tend to vary in the same direction and in a similar amount.
natch 7y ago
Airliners claim this safety by recording their fatalities "per departure." Which gives cars, which are relatively short distance vehicles obviously, a huge disadvantage. People often repeat this claim online without clarifying that airlines measure by number of departures. I haven't done a fair comparison where the same metric was used (say, fatalities per mile traveled in both transport types) but it would be interesting to see one. I'm sure airliners would still come out on top against cars, but the ratio would be different. Then if we extend this fair comparison to space, the amount of miles traveled gets rather large, so that would be interesting to see as well.
- mikeash 7y ago
  Comparing per departure would give an enormous advantage to cars. The average airliner trip is hundreds or thousands of miles. The typical car trip is single or double digits. Cars thus make many more departures for the same distance traveled, so their denominator would me much larger. The standard metric is fatalities per passenger mile. In the US, cars account for roughly 10x the number of passenger miles as airlines, so you’d expect 10x the fatalities if they were equally safe. In recent years, cars average around 40,000 fatalities per year, and airliners average around zero.
  - natch 7y ago
    Cringe, I had it backwards; thanks for the reply. I wonder if there have been any numbers published for space. Looks like the ISS does the equivalent distance of (only) 134 crossings of North America in one day. Or, stated another way, 134 people crossing it once. Clearly airlines carry way more people than that, and the fatalities are lost in the noise. So it would seem that yeah you're right, airlines are still beating space for safety by a big margin. To make space win you'd have to cheat and count something absurd like the miles our solar system travels as it orbits the galactic center... but then to be fair you'd have to credit the airlines with the same distance... so nevermind.

PhantomGremlin 7y ago

Comparing the two does not make sense. If airliners are your standard of safety for space travel, you might as well take a shortcut and just say “don’t launch humans into space.” It most certainly makes sense. A lot of sense. The Dragon capsule spectacularly blew itself to smithereens. Now is not the time to bring out some duct tape and baling wire to slap the thing back together so that it can attempt to fly astronauts into space before the end of the year. Now is the time for careful and considered testing. Not rushing. This thing needs to be safe. I can guarantee you one thing. If American astronauts die this year because of inadequate testing, that will be the last time you see American astronauts being launched into space on a NASA sponsored platform. If Americans die because this was rushed, you can kiss NASA's manned space efforts goodbye. We'll pay the Russians what it takes to keep going to ISS. And when ISS ends, NASA will be out of the manned space flight business. The operative word going forward will be "robotics".

yellow_postit 7y ago
What leads you to believe this is being rushed?
lutorm 7y ago
Space travel is not "safe", period. If you decide to go into space, you should be aware that you're exposing yourself to significant risk. The question is: what risk are you willing to accept? You may still be right about your prediction, though. But that just says something about people having unrealistic expectations.
FeepingCreature 7y ago
> If American astronauts die this year because of inadequate testing, that will be the last time you see American astronauts being launched into space on a NASA sponsored platform. And that's why the US shut down the manned space program after Challenger. > If Americans die because this was rushed, you can kiss NASA's manned space efforts goodbye. We'll pay the Russians what it takes to keep going to ISS. The lack of recent fatalities with the Soyuz does not mean the Soyuz is "safe". 141 safe launches just implies that the probability of success is p^141=0.5 (since I have no idea how likely this outcome was, I default to 50/50), so 99.5%. (edit: 99.3% with Laplace's rule.) That's very good, but it's also very very far from the safety record of airplanes.
mikeash 7y ago
Just say “don’t send humans into space.” It’ll save you a lot of typing and you end up in the same place.

bscphil 7y ago

You're right on the basic idea here, but may be wrong on the specific claim. Basically, trains and buses are also very safe, possibly even safer. In the US (important qualifier), commercial air travel sees a fatality rate of 0.07 per billion passenger miles. Also (important qualifier), that number excludes acts of suicide and terrorism. Buses see a fatality rate of 0.11 per billion passenger miles. Trains see a rate of 0.15 per billion passenger miles (not including fatalities of non-passengers). Both of those modes of transportation compare favorably with air travel. If you consider a worldwide perspective (in which pilots are on average less well trained), and include the effects of hijacked planes, it's possible one of the two might even beat it. (I'm not disagreeing with you that on a per-mile basis, air travel is very safe. I just think the specific numbers here are interesting. Also worth pointing out that for trips less than a few hundred miles, other modes are probably safer. If rail was used more for long distance travel, it would probably improve its safety record by this metric. And air travel is pretty terrible for the environment as well.) Source: https://journalistsresource.org/studies/environment/transportation/comparing-fatality-risks-united-states-transportation-across-modes-time/ https://journalistsresource.org/studies/environment/transpor...

Voloskaya 7y ago
Why spend so much energy arguing on something that wasn't even the point OP was making?
- gdy 7y ago
  Because it's fun.
mikeash 7y ago
I think those numbers are old, as you can tell from the "excludes terrorism" qualifier. If you look at, say, the last decade, terrorism doesn't make any difference. This isn't entirely arbitrary: air travel has gotten a lot safer lately. Doing the math using the data from https://www.bts.gov/content/transportation-fatalities-mode https://www.bts.gov/content/transportation-fatalities-mode and https://www.bts.gov/content/us-passenger-miles https://www.bts.gov/content/us-passenger-miles, I come up with 6,059 billion airline passenger-miles for the decade ending in 2017 (the last year provided there) and 66 fatalities, for a rate of about 0.01 per billion passenger miles. In the same period, railroads did about 176 billion passenger miles with 94 fatalities, for a rate of about 0.53. Buses did 3,234 billion passenger miles with 486 fatalities, for a rate of 0.15. The numbers vary in other countries, but I suspect they tend to vary in the same direction and in a similar amount.

natch 7y ago

Airliners claim this safety by recording their fatalities "per departure." Which gives cars, which are relatively short distance vehicles obviously, a huge disadvantage. People often repeat this claim online without clarifying that airlines measure by number of departures. I haven't done a fair comparison where the same metric was used (say, fatalities per mile traveled in both transport types) but it would be interesting to see one. I'm sure airliners would still come out on top against cars, but the ratio would be different. Then if we extend this fair comparison to space, the amount of miles traveled gets rather large, so that would be interesting to see as well.

mikeash 7y ago
Comparing per departure would give an enormous advantage to cars. The average airliner trip is hundreds or thousands of miles. The typical car trip is single or double digits. Cars thus make many more departures for the same distance traveled, so their denominator would me much larger. The standard metric is fatalities per passenger mile. In the US, cars account for roughly 10x the number of passenger miles as airlines, so you’d expect 10x the fatalities if they were equally safe. In recent years, cars average around 40,000 fatalities per year, and airliners average around zero.
- natch 7y ago
  Cringe, I had it backwards; thanks for the reply. I wonder if there have been any numbers published for space. Looks like the ISS does the equivalent distance of (only) 134 crossings of North America in one day. Or, stated another way, 134 people crossing it once. Clearly airlines carry way more people than that, and the fatalities are lost in the noise. So it would seem that yeah you're right, airlines are still beating space for safety by a big margin. To make space win you'd have to cheat and count something absurd like the miles our solar system travels as it orbits the galactic center... but then to be fair you'd have to credit the airlines with the same distance... so nevermind.