Neil Fraser wrote:
On Apr 16, 6:25 pm, Pat Flannery wrote:
On 4/16/2010 2:01 PM, Neil Fraser wrote:
The problem is, this requires both Dragon and Falcon 9 to be successful.
If we build Orion Light, we can stick it on Delta IV Heavy or Atlas V
and at least know that the booster will work.
I imagine you could stick Dragon on either of those boosters also, but
if Falcon 9 flops, will SpaceX continue Dragon development?

Ok, given the scenario where Dragon/Falcon (and all competition flops)
then what's the point of the Orion Lite lifeboat? The astronauts
would have had to come up on a Soyuz -- which would therefore be
docked and serving lifeboat duty. The only need I can see for a
dedicated lifeboat is if the vehicle which brings the crew to ISS in
the first place is unable to hang around in space for six months. The
Space shuttle is the only such vehicle.

Neil, why are you continuing to ask questions that *you* *yourself*
provided answers for in your initial post?

Without a dedicated CRV, *all* the ISS Commercial Crew vehicles would
have the six-month stay requirement levied upon them. With a dedicated
CRV, that requirement is relaxed and the Commercial Crew vehicles would
only be required to perform short-term rotation.