http://www.spaceflightnow.com/delta/...070624repairs/
that is one HUGE rocket
Established Member
http://www.spaceflightnow.com/delta/...070624repairs/
that is one HUGE rocket
Order of Kilopi
And, for some reason, that picture makes me think of a giant pez dispenser.Originally Posted by banquo's_bumble_puppy
It's nice that they mention this:
But would have been much better if they elaborated on it.It is the biggest unmanned rocket available in the U.S. inventory today.
Order of Kilopi
Kind sir, please elaborate for me?It is the biggest unmanned rocket available in the U.S. inventory today.
But would have been much better if they elaborated on it.
Order of Kilopi
Any better details would be nice. Largest? Tallest? Tonnage? Girth? Capacity? Big doesn't exactly describe what is being quantified. Ok; maybe I'm getting nitpicky, but a quick comparison to other rockets in use would be nice.
Established Member
Order of Kilopi
Any better details would be nice. Largest? Tallest? Tonnage? Girth? Capacity? Big doesn't exactly describe what is being quantified. Ok; maybe I'm getting nitpicky, but a quick comparison to other rockets in use would be nice.
With the retirement of the Titan IV-B, the Delta IV Heavy is the most powerful expendable booster in the US inventory. If Boeing ever launches their Atlas V Heavy (similar configuration to the Delta IV Heavy), then it'll probably be the most powerful booster.
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How does the thrust of this vehicle compare with the thrust of the Shuttle+SRBs and also with the thrust of the Saturn V?
Also, how does this vehicle compare with Russian heavy-lift vehicles?
Established Member
Whoa.... don't let Lockheed Martin hear you say that, they'll slap you silly.
Delta = Boeing (ex. McDonnel Douglas).
Atlas = LockMart.
.
Order of Kilopi
Delta + Atlas = United Launch Alliance.
They're under the same umbrella now.
Doug
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Woops, got them reversed. But, as djellison pointed out, it's all the same now.
How does the thrust of this vehicle compare with the thrust of the Shuttle+SRBs and also with the thrust of the Saturn V?
Much less. At liftoff, the Saturn V produced 7.5 million pounds of thrust. It was able to place 118,000 kg (260,000 pounds) into a 28 degree inclination orbit at 185 km altitude or to send 47,000 kg (103,000 pounds) to a translunar trajectory.
At liftoff, a Shuttle with 2 SRBs and 3 SSMEs running is producing somewhere around 6 million pounds of thrust (the figures on the linked article are for vacuum - it'd be somewhat less at sea level). It has an actual payload to a 28 degree inclination orbit on the order of 50,000 pounds. If you factor in the mass of the orbiter itself with the payload, it's more like 260,000 to 270,000 pounds.
The Delta IV Heavy produces approximately 2 million pounds of thrust at liftoff. According to the linked article, it has the following payload capacity:
LEO Payload: 25,800 kg (56,800 lb). to: 185 km Orbit. at: 28.50 degrees. Payload: 10,843 kg (23,904 lb). to a: Geosynchronous transfer, 27deg inclination trajectory.
In other words, it can put less than 1/4th the payload of a Saturn V into LEO but about the same or even a little better than the Shuttle.
You can research the Russian boosters at the Encyclopedia Astronautica website. It's a good source of info.
Order of Kilopi
Thanks Larry Jacks. That data puts it into perspective.
Member
The numbers on astronautixon many pages such as the shuttle are not correct. The shuttle SRB (each) does have a sea-level thrust of about 3 million pounds. On STS-107, per a NASA chart released on the SRB performance on that flight, the SRBs (each) peaked out at 3.1 million sea-level pounds of thrust, about 20-25 seconds into flight. There is confusion because the number given out sometimes is 2.5 or 2.7 million or so. This is the average thrust (check the ATK pages). The SRBs drop greatly in thrust in the second minute of their burn, down to about 1.5 million and eventually below a million.
Delta 4-Heavy is the tallest rocket in the world today at 235 feet, and is the largest US ELV in terms of weight at launch and payload capacity. It has 1.9 million pounds of thrust at launch which is less than an Atlas 5 55x.
But it cannot compare to the shuttle in weight, capability and thrust.
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Even Jim from NASASPACEFLIGHT.com has admitted reservations about this rocket.
There is something you should all remember. Why did Ares V go up to a larger core? Because RS-68 (though simple compared to SSME) really drinks the hydrolox. And yet even ET has better volume than Delta IV.
Delta IV is an awkward size. Large and unwieldy compared to Atlas, and yet comparatively narrow--too narrow to use high-volume/low-density LH2 effectively--thus my statement that Delta IV is the "Thud" of LVs.
Just like the Air Force.
Ares I can fly depressed trajectory better. Thats what you need for capsules. Delta IV is a sat-launcher--and not a very good one at that.
Saturn IB is actually small compared to Delta IV---and cheaper compared to the final Titan IVs that could put 18-20 tons in orbit.
But Saturn IB that was an Army rocket. And the Air Farce made sure it was killed.
ABMA should have stayed in charge of all things space.
Order of Kilopi
Why do we have both the Delta IV (Heavy) and the Ares V?
Administrator
For one thing we don't have the Ares V yet. For another the Delta IV (Heavy) has a much smaller lifting capacity than the Ares V
Forming opinions as we speak
Order of Kilopi
But Saturn IB that was an Army rocket. And the Air Farce made sure it was killed.
That's an absurd assertion. After the moon landings, NASA flew Saturn IBs for through all three Skylab manned launches and Apollo-Soyuz. After that, NASA dumped everything Apollo and went to the Shutte. It was NASA, not the Air Force, that pulled the plug on all of the Saturns.
As for the RS-68 verses the SSME, the RS-68 has a vacuum Isp of 420 seconds (365 seconds for sea level) verses 453/363 seconds for the SSME. The SSME has a chamber pressure of 204 bar while the RS-68's pressure is about 96 bar. That probably accounts for a lot of the vacuum Isp difference. The SSME's high chamber pressure made it an expensive engine to develop (lots of teething troubles), maintain, and operate. The RS-68 was designed to be expendable, cheaper to produce, and to produce more thrust than the SSME.
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So, will the Ares V replace the Delta IV Heavy? Or is the Ares V being designed solely for Project Constellation/Orion?
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The Delta IV Heavy has roughly the payload capacity of "The Stick" (the Ares I). That's why some suggest it's foolish for NASA to develop the Stick when the Delta IV Heavy or Atlas V Heavy boosters could do the job (without having to spend billions on R&D).
The Ares V is a heavy lifter designed solely for Constellation/Orion. As such, it'll cost billions to develop and probably only have a flight rate of 1-3 times per year at best.
Order of Kilopi
that's funny, I hit reply and suddenly another 8 posts turn up...and no, not all made while typing this
Order of Kilopi
Are delta-IVH and atlas-VH man rated?
Order of Kilopi
Are delta-IVH and atlas-VH man rated?
There is debate about what the term even means. Not every rocket that NASA has used to carry humans into space has been man rated. For example, some argue that the Shuttle doesn't meet the criteria to be called man rated.
According to this article, Lockheed is looking into human-rating (got to be PC, don't you know) the Atlas V. It wouldn't even need to be an Atlas V Heavy to launch people into orbit.
What would it take to make them human-rated? From what I've read, the biggest need would be to add some redundancy to certain components to eliminate potential failure modes and to probably add some fault detection equipment to give enough warning for the launch escape system to fire. Would that be cheap? Nope - nothing developed for aerospace is cheap. Would it cost as much as developing the Ares I? I seriously doubt it.
Established Member
tonight's the night....hope it's on tv!!!
Order of Kilopi
I don't want to crush your hopes, but...tonight's the night....hope it's on tv!!!
Remember that they only give the shuttle thirty seconds on the news.
Administrator
I think it can't have strap-on solid boosters, or anything that could drop ice chunks on to something critical for life-support or re-entry. Yes, the shuttle doesn't qualify, except for the grandfather clause.
Forming opinions as we speak
Order of Kilopi
SpaceflightNow: Mission Status Center
United Launch Allliance: Live ULA LaunchesFollow the countdown and launch of the first operational Delta 4-Heavy rocket and the final Defense Support Program missile warning satellite.
[...]
1945 GMT (2:45 p.m. EST)
Our gallery of images taken this morning showing the mobile service tower rolling back to reveal the Delta 4-Heavy rocket is posted here.
(Beware, there's a possible typo in the URLs they supply for streaming video: "laucnh" instead of "launch". Right now either, and other misspellings, give the same results: not available at this time.)View the Launch: Launch broadcast begins at 8:14 p.m. EST on Saturday, November 10.
Webcast begins:
2014 EST; 1714 PST; 0114 UTC
183-minute launch window begins:
2039 EST; 1739 PST; 0139 UTC
Last edited by 01101001; 2007-Nov-10 at 09:00 PM.
Order of Kilopi
183-minute launch window begins:
2039 EST; 1739 PST; 0139 UTC
4 hours to launch
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SpaceflightNow: Mission Status Center
United Launch Allliance: Live ULA Launches0053 GMT (7:53 p.m. EST Sat.):
All systems remain "go" for a liftoff of the Delta 4-Heavy rocket at 8:39 p.m.
Webcast begins:
2014 EST; 1714 PST; 0114 UTC
5 minutes to start of webcast
183-minute launch window begins:
2039 EST; 1739 PST; 0139 UTC
30 minutes to launch
Order of Kilopi
Webcast has begun.
Working no issues. On schedule.
Weather is not a problem.
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183-minute launch window begins:
2039 EST; 1739 PST; 0139 UTC
15 minutes to launch
Order of Kilopi
All appears well.
Poll begun...
10 minutes to launch
Edit: Ready. Ready. Ready. Poll good. All ready.
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