Author Topic: Delta 4 variants possible?  (Read 644 times)

Offline robert_d

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Delta 4 variants possible?
« on: 01/30/2012 04:21 am »
Would a notional Delta 4 heavy with a SSME or RS_25e core engine instead of the actual RS-68 increase or reduce payload? Assume the two outboard boosters would still be RS-68 powered.  Seems the trade would be higher ISP and slightly lower weight (lighter engine but added apu's) vs the gravity loss of the longer burn time.  Any other considerations?

2) What would the payload effect be of adding a second RS-68 to the outboard boosters of a Delta 4 heavy? Burn duration would obviously be reduced by half (to about 210 seconds remakably similar to the STS SRB's). This would be expensive as it would require a whole new thrust structure but I mention it with consideration of possible future recovery and re-use.