posted on Feb, 21 2005 @ 07:46 PM
Just released information on the Constellation from AWST:
The formal CEV request for proposals NASA is to issue in early March will call for a four-person CEV launch mass no greater than 20 metric tons
(44,000 lb.). In comparison, the earlier three-person Apollo Command/Service module needed for Earth orbit and lunar missions had a launch weight of
about 67,000 lb. topped by an 8,000-lb. launch escape tower, 34 metric tons total.
The Delta IV Heavy as flown in December has a 22-metric-ton capability to low Earth orbit that can be advanced to 25 metric tons with no hardware
changes. This would be done by flying a more depressed trajectory downrange of Cape Canaveral, Harvey said.
Delta IV Heavy upgrade options can be mixed and matched to various exploration mission architectures. The options that can use the existing pad
For larger payloads, however, Pratt is well into testing its new RL60 upper-stage engine that, when mated with the Delta Heavy, can begin to push the
Earth orbit capability to more than 40 metric tons.
Likewise, Boeing and Mitsubishi are examining a U.S./Japanese MB-60 with about 60,000 lb. thrust. The RS-68 first-stage engine could also be used as a
translunar-stage engine, under some Boeing studies.
Boeing has examined other Heavy unmanned cargo options using six solids to achieve in excess of 50 metric tons to orbit. Each GEM-60 has 191,000 lb.
of liftoff thrust and, by mounting them all on the same side, the vehicle can still use Pad 37 without changes.
Boeing has also looked at other IV Heavy derivatives that would cluster 5-7 common cores with 5-7 RS-68 first-stage engines for 85-metric-ton Earth
orbit payloads and 36-ton capability to Mars.
And it has considered increasing the diameter of the clustered cores from 16.1 ft. to 23 ft. for more propellant, giving the vehicle a payload
capability comparable to the 7.5-million-lb.-thrust Saturn V. But the concepts with the multiple or enlarged cores would require new pad
infrastructure and are not likely for any near-term mission options.