Delta IV Heavy Upgrade 43 t

American orbital launch vehicle. Proposed upgrade to Delta IV Heavy by adding 4 GEM-60 solid rocket boosters, RS-68 Regen upgraded engines with regeneratively-cooled nozzles to the core vehicles, cryogenic propellant densification, and an AUS-60 upper stage powered by 1 MB-60 or RL-60 27 metric ton thrust LOx/LH2 engine. 6.5 m diameter payload fairing. Introduction would require modifications to existing launch pads.

LEO Payload: 39,000 kg (85,000 lb) to a 407 km orbit at 28.50 degrees. Payload: 14,500 kg (31,900 lb) to a earth escape.