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45th and final Delta IV Weather permitting, the Delta IV Heavy will light up its three hydrogen-fueled RS-68 engines at 1:40 pm EDT (17:40 UTC) Thursday, the opening of a four-hour launch window.
United Launch Alliance teams have set a new target date for the final launch of their Delta IV heavy rocket after a previous attempt was scrubbed late in the countdown last week.
Delta IV Heavy, take a bow. From 2004 to 2024, it's been an amazing run. The final launch for United Launch Alliance's powerful rocket is one you won't want to miss. When it launches. At 2:47 p.m ...
Fiery scenes from a Sept. 24, 2022, liftoff of a Delta IV Heavy rocket. Video by United Launch Alliance The Delta IV Heavy burns ultracold liquid hydrogen, which is a high-performance fuel.
The Delta IV Heavy is carrying a classified payload for the National Reconnaissance Office, likely a spy satellite, as part of the NROL-70 mission. In its press materials, ULA described the Delta ...
Delta IV also uses ROFIs (radial outward firing initiators). They ignite at T-15s, vs. T-10s for STS/SLS. The big difference is that RS-68 is a gas-generator cycle engine, vs. the staged ...