"Dholmes" wrote in
:



If one feels it necessary to go for heavy lift, can't we at
least think in terms of "Delta-IV Super Heavy", such that
our flight hardware makes use of the engineering and production
already in use (and that will stay around if the politics of
heavy lift fails)?

This has a lot of potential.
Going from just over a 5 meter diameter rocket to an almost six meter
diameter rocket even if only for the central rocket would allow for a
lot more launch capability in a Delta Heavy.
Dual MB-60 second stage could also increase mass to orbit.

Increasing the thrust of the second stage with either a MB-60 or RL-60
and adding a third stage is IMO a must.

This appears to be Boeing's thinking, since they are proposing stacking
two upper stages, most likely using single MB-60s. Two MB-60s on a
single stage would probably require increasing tank volume to get full
benefit. The Delta 4 payload guide mentions a Star 48B third stage for
planetary missions, but does not give performance figures.

http://boeingmedia.com/images/one.cf...8856&release=t

Boeing also appears to be proposing nuclear-thermal propulsion in this
image:

http://boeingmedia.com/images/one.cfm?image_id=8864

I haven't seen Boeing's proposed solar-thermal stage mentioned, perhaps
its thrust is too low despite excellent Isp.

Getting significantly more out of the Delta 4 Heavy configuration with
existing launch facilities might mean something more radical as
converting the two strap-ons to LOX/kero and using RD-180 or a new
1 megapound kero engine being developed on the latter's technology,
and adapting the core stage to altitude ignition, as with Titan 3/4.

Benefits to unmanned planetary exploration with these improvements, too.
I wonder how much would be needed to launch that long-duration heavy
rover to Mars?

--Damon