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**Jeff Findley** · October 11th 10, 02:00 PM posted to sci.space.station,sci.space.shuttle

In article 068117cd-76f3-4aa8-82d5-
,
says...

On Oct 4, 8:48*am, Jeff Findley wrote:
In article ee37ec66-a091-43b0-b5fd-
, says...

On Sep 30, 2:52*am, JF Mezei wrote:
Jeff Findley wrote:
I agree that they don't have to be done by the same vehicle, but why do
you say they should not be done by the same vehicle?

safety why risk a crews life for any reason when automatic systems can
do the job?

This tired argument again. *The risk is worth it. *If we didn't believe
so, we wouldn't fund manned spaceflight in the first place. *Instead,
the US would do nothing but send unmanned satellites and probes out into
space.

It is not a tired argument. It is a damn good argument. Challenger's
crew died needlessly launching a comsat, which could have be done
better by an ELV. Much of station logistics is low cost items that
does not need a crew to deliver.

Challenger launching a comsat was one thing because its final
destination was GEO (a "location" where manned spaceflight does not
currently occur).

ISS crew and ISS cargo delivery missions are quite another. When the
crew and cargo are going to the very same place, putting them on the
same launch vehicle makes sense. In the case of a shuttle derived
launch vehicle with both cargo (underneath a payload shroud) and crew
(in an Orion capsule, or similar, on the very top), it makes very little
difference if you launch on one vehicle or two. The presence of cargo
*beneath* the Orion does not hamper the safety of the Orion and its crew
in any way.

This is why it's a tired argument. It only applies to the shuttle, and
even then, only in the case where the cargo and crew aren't going to the
same destination.

The aircraft analogy is not applicable.

Why is flying cargo via FedEx different than flying cargo to ISS?

The present of a crew does
not make the mission safer since the crew is the only ones at risk and
no one else, unlike an airplane.

People are more flexible than machines and their presence absolutely
does make a complex mission safer. Having a "man on the spot" to solve
problems is still better than trying to do everything remotely.

Take a closer look at the shuttle. There are many failure modes on the
shuttle which can be fixed by astronauts, but can't be fixed remotely
from the ground. Take a look at the list of possible contingency EVA's
on the shuttle and you'll quickly find that the sorts of failures these
address would turn into loss of vehicle without a crew present. Loss of
vehicle can be a danger to people on the ground.

Crew and cargo on separate launch vehicles is not a (correct) lesson
that shuttle has taught us. You can't take a single data point and draw
this sort of sweeping conclusion.

Jeff
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