Vehicle Miles Travelled

Scott Kazel mentioned "vehicle miles traveled" as a measure of safety in
a thread on sci.space.shuttle?
Are there any figures for the total VMT for astronauts and cosmonauts?
--
"Forty millions of miles it was from us, more than forty millions of miles of
void"

I was reading in the bathroom when I ran across an item written by
Jonathan Silverlight on Sun, 7 Sep 2003
22:14:42 +0100, which said:

Scott Kazel mentioned "vehicle miles traveled" as a measure of safety in
a thread on sci.space.shuttle?

Doesn't strike me as very pertinent. Mercury had a perfect safety
record, yet flew far fewer miles than any other program. Apollo's
only safety problem occurred with 0 miles flown.

Of course, we can also argue about the definition of a safety problem.

OTOH, you could argue that riding a rocket is inherently unsafe to
begin with, so the whole concept of mission safety is entirely
relative.


---------------
Beady's Corollary to Occam's Razor: "The likeliest explanation of any phenomenon is almost always the most boring."

John Beaderstadt wrote:

I was reading in the bathroom when I ran across an item written by
Jonathan Silverlight on Sun, 7 Sep 2003
22:14:42 +0100, which said:

Scott Kazel mentioned "vehicle miles traveled" as a measure of safety in
a thread on sci.space.shuttle?

Doesn't strike me as very pertinent. Mercury had a perfect safety
record, yet flew far fewer miles than any other program. Apollo's
only safety problem occurred with 0 miles flown.

Lovell, Haise & Swigert would be surprised to learn that.

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
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Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

On Mon, 08 Sep 2003 12:14:59 +0000, John Beaderstadt wrote:

I was reading in the bathroom when I ran across an item written by
(Derek Lyons) on Mon, 08 Sep 2003 05:15:32 GMT,
which said:

Apollo's
only safety problem occurred with 0 miles flown.

Lovell, Haise & Swigert would be surprised to learn that.

You deleted the next(?) line, which read something like, "Of course,
then we can argue about the definition of a safety problem."

It's possible to argue that *any* problem with a spacecraft is a
safety issue; if, however, you're going to differentiate between
safety, performance, reliability, etc, the way the OP inherently did,
then you are going to have to resign yourself to remaining within a
narrow context.

You are right in that there is a continuum of glitches ranging from a
minor annoyance, to a safety problem, to a disaster.

On the other hand, I'd venture to say that the Apollo 13 incident was
pretty far towards the safety problem end of that scale. If it wasn't a
real safety problem, it was pretty darn close.

If we are talking about fatalities per vehicle mile, then that's a
different thing, but to argue that anything less is not a safety problem
just doesn't ring true.

In message , John
Beaderstadt writes
I was reading in the bathroom when I ran across an item written by
Jonathan Silverlight on Sun, 7 Sep 2003
22:14:42 +0100, which said:

Scott Kazel mentioned "vehicle miles traveled" as a measure of safety in
a thread on sci.space.shuttle?

Doesn't strike me as very pertinent. Mercury had a perfect safety
record, yet flew far fewer miles than any other program. Apollo's
only safety problem occurred with 0 miles flown.

I didn't think so either, but I'm just wondering how close they are to
Scott's figure of 1.3 fatalities per 100 million VMT on the roads. The
total lost in space flight is about 20, depending how you do the sums,
so have they clocked up 2500 million VMT?
Of course there have been rather fewer space missions than road trips!
--
"Forty millions of miles it was from us, more than forty millions of miles of
void"

John Beaderstadt wrote:

I was reading in the bathroom when I ran across an item written by
Rick DeNatale on Mon, 08 Sep 2003 11:12:09 -0400,
which said:

On the other hand, I'd venture to say that the Apollo 13 incident was
pretty far towards the safety problem end of that scale. If it wasn't a
real safety problem, it was pretty darn close.

Let's put it this way: if the explosion had happened in earth orbit,
it would not have been nearly as threatening. The incident was only
life-threatening in the context of where and when it happened. To me,
a safety issue is life-threatening in and of itself, regardless of
context.

That's the top of a very slippery slope. At the bottom lies the
remains of Challenger, and Columbia.

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
http://www.io.com/~o_m/columbia_loss_faq_x.html

Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

John Beaderstadt wrote:

I was reading in the bathroom when I ran across an item written by
Rick DeNatale on Mon, 08 Sep 2003 11:12:09 -0400,
which said:

On the other hand, I'd venture to say that the Apollo 13 incident was
pretty far towards the safety problem end of that scale. If it wasn't a
real safety problem, it was pretty darn close.

Let's put it this way: if the explosion had happened in earth orbit,
it would not have been nearly as threatening. The incident was only
life-threatening in the context of where and when it happened.

Maybe, maybe not. For a moon mission prior to TLI, they are dead.
For a Skylab or ASTP mission, they are dead. In fact the *only* earth
orbital mission where they are not dead is an Apollo 9 type of
mission.

To me, a safety issue is life-threatening in and of itself, regardless
of context.

That's the first step down a steep and slippery slope.

At the bottom of the slope lies Challenger and Columbia.

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
http://www.io.com/~o_m/columbia_loss_faq_x.html

Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

John Beaderstadt ) writes:
I was reading in the bathroom when I ran across an item written by
(Derek Lyons) on Tue, 09 Sep 2003 04:16:51 GMT,
which said:

Let's put it this way: if the explosion had happened in earth orbit,
it would not have been nearly as threatening. The incident was only
life-threatening in the context of where and when it happened.

Maybe, maybe not. For a moon mission prior to TLI, they are dead.
For a Skylab or ASTP mission, they are dead. In fact the *only* earth
orbital mission where they are not dead is an Apollo 9 type of
mission.

What?

I don't have an A13 time line in front of me, but A13, or any other
Apollo mission, could have been "safely" brought back under similar
circumstances, at any point while in earth orbit. The only inherently
fatal A13 scenario was a post TEI explosion.

Could it not be Mr. Lyon's point that, a CM attached to an SM that
was still firmly in the SIVB Apollo Saturn V on-LEO stack would have
no way to fire a retro burn, and thus would be in deep kimchee,
at that point ?

Lets say an A13 accident happened at that point in an Apollo
Saturn V flight. What would be the capability of the dying SM
to support either an immediate transposition and docking with
the encapsulated LM, and/or, to fire the dying SM's engine for
an immediate emergency retro burn out of LEO ?

[...]

Andre

--
" I'm a man... But, I can change... If I have to... I guess. "
The Man Prayer, Red Green.

In article ,
says...
John Beaderstadt ) writes:
I was reading in the bathroom when I ran across an item written by
(Derek Lyons) on Tue, 09 Sep 2003 04:16:51 GMT,
which said:

Let's put it this way: if the explosion had happened in earth orbit,
it would not have been nearly as threatening. The incident was only
life-threatening in the context of where and when it happened.

Maybe, maybe not. For a moon mission prior to TLI, they are dead.
For a Skylab or ASTP mission, they are dead. In fact the *only* earth
orbital mission where they are not dead is an Apollo 9 type of
mission.

What?

I don't have an A13 time line in front of me, but A13, or any other
Apollo mission, could have been "safely" brought back under similar
circumstances, at any point while in earth orbit. The only inherently
fatal A13 scenario was a post TEI explosion.

Could it not be Mr. Lyon's point that, a CM attached to an SM that
was still firmly in the SIVB Apollo Saturn V on-LEO stack would have
no way to fire a retro burn, and thus would be in deep kimchee,
at that point ?

Lets say an A13 accident happened at that point in an Apollo
Saturn V flight. What would be the capability of the dying SM
to support either an immediate transposition and docking with
the encapsulated LM, and/or, to fire the dying SM's engine for
an immediate emergency retro burn out of LEO ?

An A13-type accident during parking orbit would have required some quick
thinking, but would have allowed for an RCS de-orbit within about two
hours of the event. The "good" (but leaking) O2 tank kept the single
remaining operable fuel cell working for something like two hours after
the explosive O2 tank failure. That would have allowed the CSM to
separate from the S-IVB, use the RCS to de-orbit, and land, all without
depleting the entry batteries beyond their ability to power the CM
through re-entry.

In fact, such an occurrence before TLI would probably have resulted in a
quicker decision to abort than the actual accident did, since such
significant power system problems would have pretty well made the bird
no-go for TLI. So, they'd have come down pretty quickly, I think.

The real unsurvivable points in a mission at which an A13-type accident
would have killed the crew would have been any time after the LM had
separated from the CSM and expended its DPS fuel. In other words,
at any time during or after PDI. But you could likely have survived one
at any time prior to PDI.

--

Do not meddle in the affairs of dragons, for | Doug Van Dorn
thou art crunchy and taste good with ketchup |

I was reading in the bathroom when I ran across an item written by
(Andre Lieven) on 9 Sep 2003 15:54:28 GMT,
which said:

Could it not be Mr. Lyon's point that, a CM attached to an SM that
was still firmly in the SIVB Apollo Saturn V on-LEO stack would have
no way to fire a retro burn, and thus would be in deep kimchee,
at that point ?

The evidence so far is that every conceivable malfunction was provided
for and simulated during training. I also recall that the one
imperative for the sim designers was that there had to be a solution
for the astronauts to find. That being the case, is there any
evidence that this general scenario was not provided for, or that
there was no answer to be found?


---------------
Beady's Corollary to Occam's Razor: "The likeliest explanation of any phenomenon is almost always the most boring."