On Wed, 17 Sep 2008 00:39:27 GMT, in a place far, far away, Brian
Thorn made the phosphor on my monitor glow
in such a way as to indicate that:

On Tue, 16 Sep 2008 19:04:01 GMT, h (Rand
Simberg) wrote:

So did the Titanic. Now we have lifeboats for everyone.

But we don't insist that they be able to deliver ship's complement all
the way back to Southampton. NASA demands a lot more than a
"lifeboat."

They have to. The sea lanes are relatively crowded, while LEO has
exactly one human-capable "ship". The Titanic's lifeboats were only
needed to await the next ship to come along. ISS's lifeboats don't
have that luxury.

Titanic had many ships within hours' travel of rescue The Californian
was within sight (her radioman had gone to sleep and distress rockets
were ignored by her captain, another change after Titanic was that all
large ships have their radios manned 24 hours a day) and the Carpathia
arrived on scene just after sunrise. ISS cannot expect to have other
ships available to rescue the crew within a reasonable amount of time.

Being able to "deliver all the way back to Southampton" is a lot
cheaper for NASA than having a Carpathia on standby for launch 24/7.

There are other alternatives. Such as having a Carpathia already in a
co-orbit...