[anymouse]

The rocket engines would do the major lifting. The H and He would just be used in the payload bay and structure voids to offset some of the payload weight. This only works because of the unique design that allows a large payload bay and hollow structure. The payload bay could be filled with H fuel boil-off during the long fueling process. Hard to explain the value of this without seeing the design. BTW, I only used the dirigible as a rough analog of what the structural design is. It is more advanced than that and uses proven advanced composite materials and design practices borrowed from aircraft and civil engineering.

[timer]

The design, in words, doesn’t make much sense. I get the picture that the hydrogen used for buoyancy is somehow fed thru the rocket engine. Gaseous H vs liquid H(at cryogenic temps)? No, that doesn’t work. Obviously I’ve gotten the wrong mental picture here.

I CAN see where a blimp of some kind can get you part of the way to LEO, thus reducing the fuel load; but that seems kind of retro doesn’t it? A far more efficient way to get mass into LEO is the artillery approach. EMSL was all worked out 20 years ago, the quenched superconducting rings being the best design I ever saw. Since 1# in LEO(5 mps and 100 mi up)is worth all of 4 KWH, a system efficiency of 10% = 40 cents/#(at 10 cents/KWH). That’s 16 times cheaper than postage....