I was thinking the other day about possible growth options for the Taurus 2 so that an evolved version of that vehicle could compete in the EELV class market, if events should lead to such a course in the future. The Taurus 2 seems like a good candidate vehicle to be the foundation for a launch system analogous to the current EELVs. The following ways to get there are what comes to mind; the devil would be in the details, of course. These upgrade options could be taken in different combinations depending upon what is ultimately worthwhile.
- The LOX/Methane upperstage previously suggested by Orbital. Another option open would be a different propellant/engine combination for such a stage, such as LOX/Hydrogen/RL-10 or LOX/Kerosene/AJ-26 or something else entirely.
- The addition of solid rocket boosters in various configurations. Use of the Aerojet model from the Atlas 5 would seem to be ideal, as they are from the same provider as their first stage engines, and already exist in production.
- A multi-body arrangement ala the Heavy EELVs, in either the 3 or 5 body configurations.
- A larger first stage core featuring 4 AJ-26 engines.
- An upgrade to said LOX/Methane or other upperstage featuring multiple engines, and variable tank size.
Such upgrades could create a modular system that would enable Orbital to compete across the swath of the launch market beyond current Taurus 2 capabilities. As well as that existing EELV market, there are a few other possible near term uses for such enhanced launch capability.
The first would be to serve as the launcher for an entry in the tentative commercial crew program for NASA. Orbital is well positioned to compete in such a program for a commercial crew capsule. They are an organization that is currently developing a spacecraft that could have common application to such a crewed vehicle. They also have the launch abort system specialty established in their development of such a system for the Orion spacecraft. An evolved version of their Taurus 2 launch vehicle could handle launch duties for such an Orbital commercial crew spacecraft. If that evolved Taurus 2 is not ready to be fielded in an opportune time, the alternate path of launching their spacecraft on an existing launch provider could be taken until it is. That last option is still open should Orbital not wish develop such an evolved launch vehicle.
Another application for an evolved Taurus 2 might be to better position themselves for further CRS awards, through the launch of a larger derivative of the Cygnus cargo spacecraft.
One could also imagine that if NASA were to seek commercial launch services for their Orion spacecraft, Orbital could compete to be that launch provider.
Remarkable to me is that in the near term future, an expansive commercial launch vehicle capability featuring 4 different major launch systems could be in operation, ready for whatever utilization is demanded of it.
To achieve manned launches, Orbital would likely need a whole new rocket. Both the first and second stages would need work to put men in LEO and they won't ever loft an Orion(new 2nd, 7strap-ons?).
- TaurusII uses a Solid 2nd stage. LOX/CH4 is an optional 3rd.
- TaurusII lofts about 75% of a Falcon9(Dragon).
- Falcon9 lofts about 35% of a Falcon9-H(Orion).
To achieve manned launches, Orbital would likely need a whole new rocket. Both the first and second stages would need work to put men in LEO and they won't ever loft an Orion(new 2nd, 7strap-ons?).
- TaurusII uses a Solid 2nd stage. LOX/CH4 is an optional 3rd.
- TaurusII lofts about 75% of a Falcon9(Dragon).
- Falcon9 lofts about 35% of a Falcon9-H(Orion).
who says they have to loft Orion for a manned launch.
Falcon9-H will not be used for Orion
- TaurusII uses a Solid 2nd stage. LOX/CH4 is an optional 3rd.
Orbitals website very clearly says that the LOX/CH4 is an optional 2nd stage not 3rd, it replaces the solid 2nd stage