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[WIP]United Launch Alliance Pack *V1.0RC1 Released*


Chimer4

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BlazingAngel665, mind if I give it a go and try to improve on textures?

Just give me one texture and ill post what I come up with.

I am aware my textures suck ;) I am working on new ones right now though so that is unnecessary. I am also trying to do a new CSS that has an animated vacuum nozzle.

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While technically feasible and still offered, as the Atlas V HLV and Delta IV heavy are nearly identical in lift capability, there is very little chance of an HLV ever being built. In fact, Lockheed deleted some of the required HLV hardware from the CCB tooling back in 2004, which is why there is the 30 month lead time on building one.

Lockheed flew all the parts of what was to be the first Atlas V Heavy to Florida in 2003, but never stacked or launched it because their only customer at the time (the USAF and NRO) was unable to fly the variant due to the use of the RD-180 engine, which restricts the Atlas V from being available for "National Security" missions as it is not a domestically developed or produced engine.

The Atlas V Heavy would have not had fuel crossfeed between the boosters. It would have used a modified throttle profile on the center CCB to conserve fuel during the Stage.0 flight portion very similar to how Lockheed does on the Delta IV Heavy. Fuel hoses on booster segments has always been an extremely iffy thing as the pipes are subjected to extreme forces during launch and you are playing with fire (literally) if those hoses don't fully evacuate prior to separation and the activation of the separation charges. The weight of inerting systems to prevent this would be too heavy to make it useful.

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Yes It will

The Falcon Heavy is designed for extreme reliability and can tolerate the failure of several engines and still complete its mission. As on commercial airliners, protective shells surround each engine to contain a worst-case situation such as fire or a chamber rupture, and prevent it from affecting the other engines and stages. A disabled engine is automatically shut down, and the remaining engines operate slightly longer to compensate for the loss without detriment to the mission.

Falcon Heavy will be the first rocket in history to feature propellant cross-feed from the side boosters to the center core. Propellant cross-feeding leaves the center core still carrying the majority of its propellant after the side boosters separate. This gives Falcon Heavy performance comparable to that of a three-stage rocket, even though only the single Merlin engine on the upper stage requires ignition after lift-off, further improving both reliability and payload performance. Should cross-feed not be required for lower mass missions, it can be easily turned off.

Anticipating potential astronaut transport needs, Falcon Heavy is also designed to meet NASA human rating standards. Falcon Heavy is designed to higher structural safety margins of 40% above flight loads, rather than the 25% level of other rockets, and triple redundant avionics. Despite being designed to higher structural margins than other rockets, the Falcon Heavy side booster stages have a mass ratio (full vs. empty) above 30, better than any launcher in history. By comparison, the Delta IV side boosters have a mass ratio of about 10.

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Interesting. That is something new to the design. Originally there wasn't going to be any great performance increase by doing this so it wasn't going to be included. Instead improved throttle profiles on all 3 cores would maximize performance without loss of propellant in any of the 3 tanks.

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Cross-feed yields better at-launch thrust combined with a longer burn time but reduced lift capacity past at the Stage0/Stage 1 phase (I experimented using it and not using it myself in KSP).

The advantage is the middle stage still have about 95+% of propellant when the outer stages separate meaning it can burn longer on a big booster.

The disadvantage is the centre stage also has lost very little weight and suddenly has 1/3rd of the thrust. The TWR drops significantly which makes it unsuitable for heavier payloads.

However, cross-feed can be relatively easily removed to and a conventional system can be adopted to adapt to heavier payloads if required, combined with the Delta IV-H central booster throttle-down.

Edited by MDBenson
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