How dangerous were the Apollo missions?

As the probablity of death, failure and international embarasment was so high, together with the need for a lot of luck in order to succeed, why did they name a mission 13 and not just skip to 14 ?

One of the Saturn Vs was hit by lightning shortly after lift-off. That could easily have been a very bad day. There were other launch vehicle problems that were not widely publicized.

That was Apollo 12, SCE to AUX.:wink:

Ah, yes, let’s take something that has a chance of being an international embarassment, and deliberatly make it an international embarassment. You don’t think a meaningless superstition like that wouldn’t have gotten laughed at, do you?

I actually got to talk to Gene Kranz about this once. He said flat-out that every single mission was seconds and inches away from total disaster, multiple times per mission.

Yeah.

:eek:

Comes after 12, sinical.

–Cliffy

Yeah, Apollo 13 survives the pogo oscillations on the 2nd stage only to later suffer from a sticky, welded thermostat.

Presuming the deflagration of the second stage, the results would have been as spectacular as the Challenger tragedy, but survival would have been fairly likely given the launch abort system. The Q-ball in the front nose would have detected an off-course anomaly in a matter of milliseconds and issued an abort to the command module. The CM in turn would ignite the solid fuel motor and detached from the service module and flown off to a happier place. I’ve often wondered what the public’s reaction had the pogo pre-empted the blowout in space. Wouldn’t have made much of a movie now…:wink:

Incidentally, where I worked at yesterday, I walked by an area and noticed various pieces of the Orion LAS. The abort motor nozzles were a lot larger then I thought they would be. Should ever be used in an actually emergency with astronauts, this will definitely be the double E-ticket ride of their lives.

The LEM used hypergolic fuels which ignite spontaneous on contact–hence no ignition source is needed (along with the electronics, wiring, etc.). This helps reduce the overall weight of rocket motor and increases the reliability. The trade-off is a lower impulse rate with respect to other types of types of fuels (LH2 & LO2), but those are far more complex to use (pumps, cryogenics, etc.) and the hypergolics had enough margin to make it practical for use on the moon.

So is my ten minute drive to work every day.

Realistically, what was his definition of being close to a total disaster? A fifty percent chance of an event that would cause the mission to be aborted would seem a relatively loose definition. But if that were true and it happened “multiple times per mission” (let’s define that as once per day) than a typical Apollo mission would have been aborted over 99% of the time.

NASA program managers may have talked in terms of fractional percentages for failure (Dick Feynman wrote that during the Challenger IFRB that one manager claimed a 1:100,000 failure rate) the best technical estimates of STS mortality by prime contractor engineering leads were between 1:50 and 1:100, which nicely brackets the actual failure rate. Even a simple rocket has thousands of potential failure modes, a small percentage of which are unavoidably catastrophic single point failures (SPF). The Saturn V launch vehicle and Apollo capsule could legitimately be described as being at the edge of failure during any major mission flight event, such as motor ignition, staging, separation, and atmospheric re-entry, and failures at those modes would be essentially unrecoverable. The Shuttle STS, which its massive increase in complexity, is even worse, and the fact that it works at all is an amazing testament to the ability of engineers who were working with computers and software hardly more complex than your average modern scientific calculator.

Shamefully, however, the modes that resulted in the flight failures of Challenger and Columbia weren’t some kind of unforeseen, unavoidable events; the problems that led to these disaster were well-known, documented, and entirely avoidable (or at least capable of significant mitigation). The failures in these cases are largely due to human error of judgment and bureaucratic inertia. Ditto is arguably true for the Apollo I pad fire and the Apollo XIII failure.

Comparisons to terrestrial hazards like driving are not apropos; while the odds that you might get in an accident due to driver error are not insignificant, the actual incidence of accidents is quite low compared to the amount of time spent in transit, and the severity of most accidents is limited to reparable damage to cars and passengers. Failure in flight of a space launch vehicle, on the other hand, is frequently catastrophic and without useful mitigation.

Stranger

Yeh - i realise its the next number after 12 etc. Very good. Well done everyone. But its not as if 13 isnt generaly considered to be unlucky.

Many US buildings dont have a 13th floor, some airports dont have gate13, many aircraft dont have seat / row 13. In fact some of your streets arnt even numberd 13. You DO have a history of not being 100 % comfortable with it as a nation !

Allow me to note that we occasionally have found 13 to be just the right number, my sinical *british* friend.

:slight_smile:

And tested far more exhaustively.

One set of bugs is listed here.

Another close call was Gemini 8. Uncontrolled spin due to a thruster being stuck on.

Those are all open to the public and there are people who have irrational superstitions. But Apollo missions didn’t have to sell tickets.

Man - that Armstrong guy on Gemini 8.

Sounds like he had a pair of big brass ones. So big that they’d probably throw off any calculations made for space travel - whatever happened to him?

You’re right. Just the other day I heard something (think it was the History Channel) about this possibility. In fact, there was a big solar storm between two of the moon missions.
Regarding the explosion on 13: I suspect that what saved their hides when tank two blew was that it happened in a vacuum - as soon as the tank ruptured, The Void eagerly sucked up most of the energy released. Sounds plausible, anyway.

The size and physical properties of Mr. Armstrong’s testicles were taken into account during his selection into NASA’s astronaut program.

For what it’s worth, I heard the contingency plan was to turn the bottom end of the Service Module with the nozzle pointing towards the Sun and hope that the re-entry shield would attenuate the primary radiation. How well would it work? Beats me. The following suggest not much: The astronauts that went to the moon were on average suffering cataracts about four years earlier then average non-lunar voyager (I have no cite for this other than reading it in a magazine in the last millennium.)

Another way of saying this is that there was no compressible media in front of the shock wave to build up the hammer effect. Interesting, I’d never thought of what the differences between detonating a conventional high explosive at sea level vs. 250,000 feet, and what kind of damage would result to objects near and far away. Anyone got a link to information like that? Don’t bother with nuclear explosives.

Addendum to that, you’ve got to realize that an astronaut is a person who will knowingly and willingly sit on top of a three hundred foot tall pile of explosives and deliberately set it off. Forget about irrational fears; these guys don’t even have rational fears.

Partly my own teenage perception; partly media filters – but I don’t think the US public had any real appreciation for how dangerous manned spaceflight really was. I remember hearing & reading about glitches (like Gemini 8), but never felt that anyone was in any real danger. As a whole, every flight was so successful that I personally felt the US space program was bullet-proof. Even during Apollo XIII, I never really doubted they’d return safely. We’re Americans, after all – we can do 100 impossible things before breakfast.