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Questions tagged [delta4-heavy]

Delta 4 Heavy uses three of the Delta 4 Common Booster Cores side by side to launch heavy payloads.

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Why does the Delta 4 Heavy look burned? [duplicate]

When I was looking at pictures of the Delta 4 Heavy rocket, I noticed that closer to the engines, the rocket looks black instead of the orange color it has right after launch. It looks burned to me. ...
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3answers
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Velocity of the Parker Probe when it will be given final boost by the rocket?

What is the current speed of the parker probe which is just launched today(After Final boost(detached by the rocket)). I was just guessing as it will attain max speed of ...
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1answer
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What is the blue/red flare at the Delta IV Heavy launchpad

I was watching the (eventually scrubbed) launch of Delta IV Heavy with the Parker Solar Probe. I noticed a fairly large blue/red flare near the launch pad. I'm guessing it's LH/LOX, but I thought ...
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3answers
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How does the Parker Solar Probe have such a wide launch window?

The Parker Solar Probe is set to launch on August 11th 2018. It will perform 7 orbit-lowering gravity assists around Venus for ~6 years before reaching its final operational orbit. It has been well ...
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1answer
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Why can't Falcon Heavy accelerate deep space payloads as fast as Atlas V and Delta Heavy?

A Falcon Heavy with an expendable core costs $95M and lifts 2.5x as much to GTO as the Atlas V. It's Pluto injection orbit payload is nearly half of the Atlas V's GTO payload. In the answer to this ...
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1answer
243 views

What is the current status of delta IV heavy 7 (in 2017)?

I cannot find references if the Delta IV heavy 7 except on this wikipedia image. It consists of a Delta IV heavy with 6 boosters. There may be a need for such powerfull launcher (otherwise the SLS' ...
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1answer
843 views

Why are some rockets orange?

After many successful launches with the Delta II, ULA made the Delta IV rocket orange. What's the reason for this strange color change? Also the Atlas V's first stage is orange, is there any ...
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1answer
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How can the same upper stage be optimal on a common core booster as well as on a single booster?

Bundling three or five first stage cores together improves the launch capacity a great deal. But Delta, Falcon and Angara are supposed to use the same upper stage in their multiple common core ...
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1answer
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Delta IV Heavy trans-lunar injection mass

What is the mass capacity for the Delta IV Heavy for a trans-lunar injection? Or is there a way to take its capacity to GEO or LEO and substitute it into a formula which would bring the approximate ...
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1answer
102 views

What does the US Govt get out of its Assured Access funding of ULA?

ULA gets a so called subsidy (currently purported to be $800 million a year, since it is being considered to be cancelled) for Assured Access to space. Their lack of a bid on the GPS3 launch contract ...
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2answers
1k views

Could a Delta 4 Heavier be built?

The Delta 4 vehicle is a common booster core (CBC) design, where a single booster design can be used to launch in single stick mode, or in triple stick (Heavy) mode. The single stick model also has ...
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3answers
628 views

Who built the sparklers used by the Shuttle program during launch?

The Shuttle main engines used LH2 and LOX, and used sparklers to burn off the hydrogen that would be exhausted, unburned, during engine startup. (They pre-chill the engine components so that they are ...
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What makes Falcon Heavy with 3 booster 4 times more capable than single booster F9?

Falcon Heavy is expected to take 4 times more mass to LEO than Falcon 9 (53 instead of 13 tons). Are bigger rockets generally about 4/3 times more capable per fuel mass and engine thrust? It doesn't ...
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0answers
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What is happening in the few seconds surrounding t=0 of the Delta IV Heavy launch? [duplicate]

Watching footage of the Orion test launch on Dec 5th, one can see orange flames rise up from the base of the rocket in the few seconds before t=0 and before the engines appear to fully "fire up". ...
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1answer
403 views

What's next for Orion?

Orion's Exploration Flight Test 1 today appeared to go very well. The only information on future Orion flights I was able to find suggests that the next step is an unmanned circumlunar flight ...
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4answers
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Why do rockets separate from both its strap-on booster cores simultaneously instead of one at a time? (Delta IV Heavy, Falcon Heavy, Angara)

The basic idea of staged rocketry is to get rid of the mass of empty tanks et cetera as soon as possible during launch, isn't it? So you would ideally want to drop them one at a time as soon as they ...
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1answer
177 views

Will the EFT-1 mission for Orion carry an escape tower?

December 2014 is the scheduled date for the Exploration Flight Test-1 (EFT-1) mission of the Orion space capsule. It will be launched on a Delta IV Heavy rocket as a surrogate for the unavailable SLS ...
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1answer
560 views

Are the three core boosters in a Delta 4-Heavy interchangeable?

I was reading an article about the 2 of the 3 cores arriving by barge from Decatur at CCAFS and it noted that the two would be the Starboard and center cores. This made me wonder what differences in ...
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1answer
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Why not use Sparklers on Delta-4 Heavy launches to burn off the hydrogen?

With three CBC (Common Booster Core) modules firing their RS-68A engines simultaneously, a Delta 4 Heavy launch is an impressive sight. The RS-68 is a LOX/LH2 engine. As part of the launch sequence, ...