What is the Crew Exploration Vehicle supposed to be?

While reading articles about the Moon-to-Mars plan, I've seen frequent
mention of the Crew Exploration Vehicle. Unfortunately, even after
looking through some online resources, I'm still confused about what
exactly the CEV is supposed to actually be.

Is it supposed to be just a capsule (hopefully compatible with
different types of rockets already developed or in-development), or is
it a capsule + rocket combination?

Is the same vehicle intended to be used to travel to LEO (and dock with
ISS) -and- land on the moon -and- land on Mars? If so, that sounds like
a recipe for disaster, almost as bad as using the same vehicle for both
passenger transport and heavy cargo.

-- Neil Halelamien

Neil Halelamien wrote:

While reading articles about the Moon-to-Mars plan, I've seen frequent
mention of the Crew Exploration Vehicle. Unfortunately, even after
looking through some online resources, I'm still confused about what
exactly the CEV is supposed to actually be.

Is it supposed to be just a capsule (hopefully compatible with
different types of rockets already developed or in-development), or is
it a capsule + rocket combination?

Is the same vehicle intended to be used to travel to LEO (and dock with
ISS) -and- land on the moon -and- land on Mars? If so, that sounds like
a recipe for disaster, almost as bad as using the same vehicle for both
passenger transport and heavy cargo.

It's still TBD, but the conventional thinking on it is that it's a suite
of modules--a capsule for entry and crew life support, and kittable
modules analogous to an Apollo service module. It may be part of a
system that eventually goes to Mars, but it's unlikely that it would be
the whole of it. And it's not a launch vehicle--it's a payload.

In article ,
Neil Halelamien wrote:
...I'm still confused about what exactly the CEV is supposed to actually be.

That's partly because the CEV is not yet very well defined.

Is it supposed to be just a capsule (hopefully compatible with
different types of rockets already developed or in-development), or is
it a capsule + rocket combination?

The way the wind is blowing is that it will be a capsule launched on an
EELV derivative, i.e. roughly an existing rocket. But there is no final
commitment to that yet. It is definitely envisioned as a *spacecraft*,
not a *launch vehicle*. NASA is out of the launch-vehicle business for
the moment, except for that nagging possibility that the KSC-MSFC-JSC axis
will get its wish for continuing full employment in the form of a shuttle-
derived heavy-lift launcher.

Is the same vehicle intended to be used to travel to LEO (and dock with
ISS) -and- land on the moon -and- land on Mars?

Again, most of these questions don't have firm answers yet. The approach
people seem to be centering on is that the CEV would be the mother ship
for a lunar mission, with a separate vehicle flying the landing, as in
Apollo. Whether that is the best approach is a very different question.

As with Apollo, once you decide that the mother ship never goes lower than
lunar orbit, the differences between it and an Earth-orbit spacecraft are
small: bigger propulsion system, a tougher heatshield, various minor
differences in subsystems.

Mars is not even really a consideration in current hardware design; Mars
landings are far off in the misty future even in Bush's concept.

If so, that sounds like
a recipe for disaster, almost as bad as using the same vehicle for both
passenger transport and heavy cargo.

There's nothing wrong with using the same vehicle for both passenger
transport and heavy cargo. Most air cargo flies in the cargo holds of
widebody passenger airliners. A launch vehicle which is reliable enough
to be trusted (in a sane world) with billion-dollar space-station modules
is plenty reliable enough to carry people. (Would you entrust *your*
extremely expensive cargo to an aircraft which wasn't considered reliable
enough to safely carry passengers?)
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Henry Spencer wrote:

There's nothing wrong with using the same vehicle for both passenger
transport and heavy cargo. Most air cargo flies in the cargo holds of
widebody passenger airliners. A launch vehicle which is reliable enough
to be trusted (in a sane world) with billion-dollar space-station modules
is plenty reliable enough to carry people. (Would you entrust *your*
extremely expensive cargo to an aircraft which wasn't considered reliable
enough to safely carry passengers?)

Yes, there's no such thing as a "man-rated" air transport. This is
another bit of current conventional wisdom that must be eradicated.

"Rand Simberg" wrote in message

Henry Spencer wrote:

There's nothing wrong with using the same vehicle for both passenger
transport and heavy cargo. Most air cargo flies in the cargo holds of
widebody passenger airliners. A launch vehicle which is reliable enough
to be trusted (in a sane world) with billion-dollar space-station
modules
is plenty reliable enough to carry people. (Would you entrust *your*
extremely expensive cargo to an aircraft which wasn't considered
reliable
enough to safely carry passengers?)

Yes, there's no such thing as a "man-rated" air transport. This is
another bit of current conventional wisdom that must be eradicated.

On a related note regarding crew and cargo launching, the Vision for Space
Exploration spells out an action to be taken:

"Separate to the maximum practical extent crew from cargo transportation to
the International Space Station and for launching exploration missions
beyond low Earth orbit;"

This of course refers to launching crew and cargo separately, not which
vehicle would be used to launch each.

Jon

In article ,
Jon Berndt wrote:
another bit of current conventional wisdom that must be eradicated.

On a related note regarding crew and cargo launching, the Vision for Space
Exploration spells out an action to be taken:
"Separate to the maximum practical extent crew from cargo transportation to
the International Space Station and for launching exploration missions
beyond low Earth orbit;"

Yes, that was a very conventional-wisdom document in a number of ways.
Note that it says nothing much about improving even the cost of launches,
never mind their reliability.

Also, some people advocating such a separation have an ulterior motive:
they see little hope of prying control of manned spaceflight operations
away from NASA in the near future, but think that if the two roles are
separated, then NASA can probably be convinced to relinquish cargo
operations to private industry.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

"Rand Simberg" wrote in message
nk.net...
Yes, there's no such thing as a "man-rated" air transport. This is
another bit of current conventional wisdom that must be eradicated.

There is, however, the airworthiness certificate issued to a manufacturer
upon successful completion of a test program that satisfies FAA
requirements. It is roughly analogous to "man-rating", in that the aircraft
cannot be operated without one.

-Kim-

Kim Keller wrote:

Yes, there's no such thing as a "man-rated" air transport. This is
another bit of current conventional wisdom that must be eradicated.


There is, however, the airworthiness certificate issued to a manufacturer
upon successful completion of a test program that satisfies FAA
requirements. It is roughly analogous to "man-rating", in that the aircraft
cannot be operated without one.

No, that is a completely different definition of man-rating. To the
space community, that term means a vehicle that *can* carry a human, not
one that must. An airworthiness certificate means that the aircraft is
capable of flying in public airspace, and has nothing to do with whether
or not it will have a pilot (thought the notion that an aircraft with
such a certificate wouldn't have a pilot would be a foreing concept to
most, includin the FAA).

Rand Simberg wrote in message ink.net...

There is, however, the airworthiness certificate issued to a
manufacturer
upon successful completion of a test program that satisfies FAA
requirements. It is roughly analogous to "man-rating", in that the
aircraft
cannot be operated without one.

No, that is a completely different definition of man-rating. To the
space community, that term means a vehicle that *can* carry a human, not
one that must. An airworthiness certificate means that the aircraft is
capable of flying in public airspace, and has nothing to do with whether
or not it will have a pilot

Furthermore, NASA is quite willing to talk about a CEV that lands in
the US (and overflies populated areas) even before it is not
"man-rated." Protecting the lives of test pilots is somehow deemed to
be more important than protecting people on the ground. In that sense,
"man-rating" is the opposite of an airworthiness certificate, which is
meant first and foremost to protect the public.

The FAA views pilots, quite properly, as operators who are responsible
for the safety of their aircraft. They are considered even more
important on initial test flights. NASA engineers, on the other hand,
tend to view pilots not as contributors to safety but as additional
risks, to be avoided whenever possible. A frequent refrain is "we
should never send humans to do anything a machine can do."

"Rand Simberg" wrote in message
nk.net...
No, that is a completely different definition of man-rating. To the
space community, that term means a vehicle that *can* carry a human, not
one that must. An airworthiness certificate means that the aircraft is
capable of flying in public airspace, and has nothing to do with whether
or not it will have a pilot (thought the notion that an aircraft with
such a certificate wouldn't have a pilot would be a foreing concept to
most, includin the FAA).

Note that I did say "roughly analagous". But I would like to see you try to
sell or operate an airliner without a standard airworthiness certificate.

-Kim-