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SLS / Orion / Beyond-LEO HSF - Constellation => Orion and Exploration Vehicles => Topic started by: Svetoslav on 04/15/2006 08:35 am

Title: Making the Crew Exploration vehicle reusable.
Post by: Svetoslav on 04/15/2006 08:35 am

I think that the main reason of replacing the SSME with J2-X is that the second stage of the spacecraft won't be reusable.

Launching a space shuttle is clear. After jettison of the SRBs the shuttle swithes to a second stage: the external tank, the orbiter and her engines.

But CEV would be different. The first stage will be reusable, because it is a single SRB that could be refubrished. The problem is with the second stage. After the orbit burn, it will jettison from the capsule with the crew and probably will burn into the atmosphere.
So what? Can we think of a way to make the second stage reusable?

Title: RE: Making the Crew Exploration vehicle reusable.
Post by: Tap-Sa on 04/15/2006 11:37 am

The shuttle doesn not 'switch' to second stage after SRBs burn out. The SSMEs burn during the whole flight, from liftoff to ET separation. It's the airstart in CLV (after stage separation) that's problematic to SSME, it would need redesigning for that.

Title: RE: Making the Crew Exploration vehicle reusable.
Post by: Jim on 04/15/2006 03:21 pm

The CEV is reusable, except for the service module.  Making the 2nd stage of the CLV  recoverable would take a whole lot of TPS and parachutes which are all weight and a recovery force in the Indian Ocean.

Title: RE: Making the Crew Exploration vehicle reusable.
Post by: kraisee on 04/20/2006 07:14 pm

Does anyone have any further news about Griffin wanting disposable SRB's to try to reduce costs?

It did the rounds on the rumour mill, but seems to have gone quiet since.

Ross.

Title: RE: Making the Crew Exploration vehicle reusable.
Post by: Avron on 04/21/2006 03:18 am

Jim,


What makes the a SSME reusable (apart from the fact that the land back)? and what would be " reduced " to allow it to be disposable (lower the cost), even if it could be air started ?

Title: RE: Making the Crew Exploration vehicle reusable.
Post by: Jim on 04/24/2006 02:09 pm

Quote

Avron - 20/4/2006  11:18 PMJim,What makes the a SSME reusable (apart from the fact that the land back)? and what would be " reduced " to allow it to be disposable (lower the cost), even if it could be air started ?

I couldn't honestly tell.  Just that is built to take repeated loads, to me means extra material