Article from Aviation Week:

DENVER - NASA's planned Ares V heavy lift vehicle can't meet its lunar-mission requirements as currently conceived, and will need beefing up.

The agency is studying a variety of options to boost the lift capability of the big new rocket, currently scheduled to begin development before the end of 2010 under the fiscal 2011 federal budget.

Initially planned as the largest launch vehicle ever built, the Ares V has grown as engineers in NASA's Constellation Program gain a better understanding of the vehicles that will be needed to send four humans to the moon for a seven-day stay, and eventually to build on that early presence into a lunar outpost where astronauts can live for as long as six months at a time.

But even with expansion from earlier concepts to a full 10-meter diameter all the way up to the fairing that will cover the Altair lunar lander, allowing the upper stage to carry more propellant, Ares V still falls short, according to Phil Sumrall, advanced planning manager in the Exploration Launch Projects Office at Marshall Space Flight Center.

"The payload requirements are very driving and very difficult to get to, and frankly our vehicle today is close but doesn't quite meet those mission requirements," Sumrall told the Third Space Exploration Conference & Exhibit here Feb. 26.

In gross terms, the Ares V needs to send about 75.1 metric tons into trans-lunar injection, including margins. But the vehicle as conceived today can only throw 63 or 64 metric tons, Sumrall said, which leaves it "actually a couple of tons short of where we need to be, without margin."

Add that to the weight/performance issues they're having with the Ares I/CEV.

2 more SRB's ?

That would be overkill. It would also mess up the launch pad geometry. The article mentions they're considering extending the SRBs to 5.5 segments, increasing the propellant capacity, and perhaps adding a sixth RS-68 engine to the first stage. Those would probably get the payload up to what's needed but they seem like a lot of redesign at this point.

...and if you did a multi-jillion-dollar design study to fit their needs, the vehicle they need looks like:



What a shock!!!!

If six, why not seven so that you have a filled hexagon of engines?

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I will be shocked if this big booster ever gets off the ground. When the politicians cancel the back to the Moon mission, they will probably argue that a booster this size is not needed, and cancel the Ares V project as it's getting close to completion. Better to spend the funds on something that gives us a better payback, like a new and expensive weapons system.

I think the best way to keep this booster alive is to convince the politicians and the Military that a booster this big can also carry a really big load of nukes; and the contruction of our first Moon Super Laser will start shortly after we establish our Moon Base. Also, let's not forget that China is working very hard to build their very own Super Laser on Mars!

Dr. Evil may have been right.

If the server would provide the image, you'd see a Saturn V.

Edit: The server is coughing up the image now, so I'll edit the quote that included it. I'll leave the link to the same Wikipedia image because it's probably more reliable, just in case. (And there is one of my issues with articles that only link to something without describing it with a little extra text: if the link fails, the article fails to communicate.)

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Just being sarcastic. I think the NASA gets seriously short-changed when it comes to funding, even as the Military is given almost unlimited funds. I've never liked the way that projects are cancelled after so much work is done. The Saturn V should not have been cancelled and the Ares V should go forward as planned, even if the manned Moon mission is scrapped at the last moment. Having a heavy lift capability, will make many future manned and unmanned missions possible, at a lower overall cost. I'm keeping my fingers crossed, and hoping that our elected politicians can see that space science projects are important and hopefully, more funding is given to NASA.

If you cancel the Moon landings and don't replace the ISS, why would you need a booster that size?

There has been some effort made to support the idea of using it for unmanned space efforts, such as giant space telescopes of various sorts, and bigger deep space probes. I think they know that a delay in the return to the Moon can't be discounted as a possibility.

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I think that the Ares V would be very nice to have around if we ever had a need for an asteroid deflection mission. It could send up a much larger payload to the target, or get a smaller payload there faster than by using a smaller booster.

Larger and more complex deep space missions, like sending a drilling mission to Europa, or a rover/airship to Titan, would also benefit from having a heavy lift capacity.

Doesn't NASA need the Ares V for Constellation Mission?

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Yeah, but I think some are exploring the hypothetical which assumes no Constellation is needed:

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Doesn't NASA need the Ares V for Constellation Mission?

To achieve the goals for the Constellation Mission, NASA needs the capability to put a lot of payload into LEO and subsequently into a translunar trajectory. The question is how to achieve that capability. Ares V is their proposed vehicle to do the job but it isn't necessarily the only or even the best way to capability. For example, they could use several EELV (Delta IV Heavy or Atlas V Heavy) or Falcon 9 Heavy flights to put the same payload into orbit without incurring billions of dollars in R&D costs. The increased flight rate would have the added benefit of lowering the per mission costs substancially. Or, they could contract out the heavy lifter to Energyia. However, given the cooling of relations between the US and Russia lately, that might not be a good idea.

With a new president taking office next January 20th, it's not at all certain if missions beyond LEO will survive. There's a large thread on this very topic on this page.

Launch vehicles cost a lot to develop. They also have significant fixed annual costs regardless of the mission flight rate. The only way to justify such expenses is to have specific missions in mind. While there is a certain amount of "build it and they will come" belief out there, a lot of that is wishful thinking.

The military doesn't have any payloads now or on the books that would require a HLV to launch. Developing those payloads is a long and expensive process. Nor would an Ares V make a good weapons delivery platform due to the days, weeks, or months it takes to prepare one for launch. The mlitary is trying to go the opposite direction with a concept called operationally responsive spacelift.

Likewise, a heavy lift capability would be useful for building a new space station but there are no plans on doing so. It'd be great to launch very large scientific satellites but there aren't any in existance or in the planning stage. Sure, it'd be useful for an asteroid intercept mission but that would mean assembling the payloads and keeping them along with the necessary launch vehicles in storage until the need arised, if ever. That would also require keeping the necessary personnel for preparing and launching the rockets on the payroll regardless of if there are any launches. That would cost at least a few hundred million dollars a year. This is one of the reasons why the Saturn Vs were scrapped. They were magnificient rockets - big, powerful, and beautiful. However, after the Apollo moon missions and Skylab were launched, there were no missions on the books that required anything like that payload capability. It would've been cost prohibitive to keep the assembly lines, ground infrastructure, and all of those thousands of personnel on hand when there was no mission that required such a heavy lift capabilty on the books.

All of this is a long-winded way of saying that payloads and operational needs drive booster development far more than the other way around. Once the booster is developed, payloads can be sized to take advantage of the lift capacity. However, when you're talking about very large payloads launched by a HLV, this isn't going to happen very often.

Larry, once the Ares V is developed and operational, I don't really understand why it would so difficult to keep it as part of our rocket inventory. We have many kinds of boosters that offer different capacities for launching payloads into space. Not all these boosters are used all the time; different missions require different boosters. Isn't it the same builders that build smaller and bigger rockets? Isn't it the same launch personnel that launch the different types of rockets? Now that the Shuttle is being retired, why can't the personnel that assembled and launched Shuttle be used on the Ares?

I'm a layman when it comes to how NASA works, but I am part of the management team of a large manufactoring plant, and it seems that some type of modular design would be good for making different types of rocket boosters.

I'm a layman too, but I'm not sure that we have that many different kinds of boosters at any point in time. I came upon this wikipedia page of Merritt Island launch sites recently. If you look at what they list as "active" launch vehicles you have:
- The Shuttle
- Delta II
- Delta IV
- Atlas V
- Aries (which really isn't active yet).

So really you just have the Delta family, the Atlas, and the Shuttle. I have to believe there is quite a bit of work to keep the parts, tooling, etc. for each line so you can manufacture the boosters. And though it may be the same personnel on the ground, I got to believe the procedures, tooling, etc. are very different for each one.

I also found this Wikipedia page which gives a comparison table of heavy lift launch systems interesting.

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Larry, once the Ares V is developed and operational, I don't really understand why it would so difficult to keep it as part of our rocket inventory.

Like Swift pointed out, there are really only a few families of boosters. For example, there are several variants of the Delta II that mainly differ by the number of strap-on solids. There are several versions of the Delta IV but they have a lot of commonality. The same is true for the Atlas V family. That means the personnel who are trained to service and launch one variant are capable of launching the over versions with little or no additional training and equipment. The Delta IV and Atlas V EELVs were specifically designed to require fewer personnel and less time to prepare for launch than earlier boosters. The Shuttle, by contrast, requires several thousand people to prepare for flight.

It takes a lot to have an operational booster capability. In addition to the production pipeline consisting of many subcontractors and a lot of specialized (and expensive) tooling, you need a booster processing facility. In the case of the Ares V, that would be the VAB. You also need payload processing facilities. All of this work requires skilled personnel and specialized test equipment. You need a launch pad and fueling facilities adapted for the booster. You also need a launch control center with associated personnel and equipment. In addition, to prepare the booster for flight, you need software tailored for the mission. All of that costs money, especially the personnel. Good geeks don't come cheap and those are part of the fixed overhead costs that are there regardless of whether you launch any vehicles or not in a given year (as happened when the Shuttle was grounded for years following the Challenger and again following the Columbia accidents.

A lot of the Shuttle servicing personnel can be brought over to work on the Ares I and V. In fact, it appears that maintaining their personnel was one of reasons why NASA designed the Ares I & V around as much Shuttle hardware as possible. Only, it's turning out that so much of the "off-the-shelf" hardware is having to be modified to make the Ares designs work. For example, the Ares I's first stage is supposed to be a Shuttle SRB but now it's being extended to 5 segments instead of 4. It'll probably have a new internal propellant geometry that'll require additional R&D. The second stage was originally going to use a SSME but they couldn't make it air-start so they were going to use an upgraded Saturn J-2 called the J-2X. Unfortunately, that engine is requiring a lot of additional R&D as well. The Ares V will use 5 (or 5.5) segment SRBs with the possibility of needing composite casings. Other than that, there isn't so much commonality with the Shuttle after all. That means the ground servicing personnel will need a lot of specialized training and equipment to prepare an Ares vehicle for launch.

The Ares V - if built - will have a very large payload capacity. There just aren't many payloads that big that need launching. As a result, the flight rate is likely to be no more than 1-3 flights a year, max. If the vehicle was in service for 20 years, that means you'd probably launch no more than 20-60 of them. Take the billions for R&D and divide that by the number of flights. Add in the cost of building the rockets which won't be cheap (the Ares V will likely have 6 RS-68 engines each at a cost of several million dollars each, for starters). Divide the fixed overhead expenses by the annual flight rate and add that to get the cost per flight. If they manage to fly it twice a year, each flight is likely to cost a total of at least $2 billion. There simply won't be too many customers lining up to pay that kind of launch cost.

Lower the launch rate and the cost per flight increases sharply (I had to resist the temptation to say "goes ballistic" or "skyrockets"). It's like what happened with the B-2 bomber and the F-22 Raptor. They spend huge amounts of money on R&D and then cut the production run (21 for the B-2 and less than 200 for the F-22). As a result, the per unit cost for both planes is very high. So are the costs for upgrades because they're spread over so few planes.

Interesting link Swift. Thanks.
I didn't know that the Titan boosters were retired. I still thought that they were used from time to time.

A modular approach to booster manufactoring would be nice. You could make different boosters using interchangable booster elements in order to configure the stacks for differrent lift requirements.

Thanks, Larry. You know your stuff. I am not a big fan of the Ares I, but I do hope that the Ares boosters go forward. Is it possible for a heavy lift booster like the Ares V to be used to deploy multible satellites, so instead of using two or more smaller rocket boosters, just one ares V could be used?

A modular approach to booster manufactoring would be nice. You could make different boosters using interchangable booster elements in order to configure the stacks for differrent lift requirements.

That's what they did with the Delta IV and Atlas V EELVs. Each family has a common core. To that, they can add varying numbers of strap-on solids or go all the way to 3 common cores in parallel. They also vary the payload shroud size.

For the Deltas, there's the Delta IV Small, Delta IV Medium, Delta IV Medium 4.2, http://www.astronautix.com/lvs/delium52.htm, Delta IV Medium 5.4, and the Delta IV Heavy. There are proposed growth versions for the Heavy.

Atlas V info is available here.

The US has a few other boosters. There are the Pegasus and Pegasus XL air launched boosters, the Taurus, and SpaceX is developing the Falcon 1, Falcon 9, and the planned Falcon 9 Heavy. It appears the Athena 1 & 2 are out of production.

The last of the Titans flew on in 2005.

Thanks, Larry. You know your stuff. I am not a big fan of the Ares I, but I do hope that the Ares boosters go forward. Is it possible for a heavy lift booster like the Ares V to be used to deploy multible satellites, so instead of using two or more smaller rocket boosters, just one ares V could be used?

Yes, it's possible to do that. Ariane V was designed to launch large payloads, typically two large communications satellites. However, that can cause problems. For one thing, you're putting a lot of expensive satellites on one booster. If it should fail, you'll lose all of the payloads. Failures happen.

There's also the question of operational flexibility. Companies invest a lot of money in their satellites. They don't start to recoup any of that investment until they're on orbit and in operation. Sometimes, there are delays in completing a satellite. The more satellites you put on a single booster, the harder it is to get them all ready to go at the same time. Customers get unhappy if their launch is delayed for months due to someone else's problem. There could also be issues of satellites needing to go into different orbits. It's fine if they're all bound for geosynch but you can have problems if some of them need to go elsewhere (such as a semi-synch GPS orbit).

For most payloads being launched or developed now, an Ariane V, Atlas V, Delta IV, or perhaps the Falcon 9 are suitable.

That's good. We're going to do it, so let's do it right.

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So a multi-jillion dollar study would reveal that you in fact need a LESS powerful rocket?

NASA needs a bigger what?

Oh, a bigger Ares rocket. I understand now, carry on.

Its not a big deal. Delta IV would throw away 21 RS-68s per 140 tons to LEO. Upgraded Ares V needs only six--and may evolve to 180 tons to LEO.

That's NOVA class.

I say we strap 3 Saturn V's together. I don't know why i just would like to watch the wavelength make everything go crazy-nuts.

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That's more like what Team Vision wants
http://orbit.m6.net/Forum/Default.aspx?g=posts&t=17832

More
http://forum.nasaspaceflight.com/ind...topic=10870.30
http://forum.nasaspaceflight.com/index.php?board=21.0
http://www.nasaspaceflight.com/content/?cid=5451

The latest
http://www.nasaspaceflight.com/content/?cid=5481

A Quote:
"It's still early days in the development of the mammoth Ares V, with further configuration changes not ruled out - especially based on gaining performance. The largest 'viable' Ares V to be noted is 'Ares V Max' - which consists of seven RS-68s and two 6.5 segment boosters."

"Even taller variants have also been documented, but all are too tall to fit inside the Vehicle Assembly Building (VAB), and are classed as requiring a new giant Vehicle Integration Building (VIB) to be built -"

Discussion

http://forum.nasaspaceflight.com/ind...topic=12363.90
http://forum.nasaspaceflight.com/ind...topic=13737.30
http://forum.nasaspaceflight.com/ind...?topic=13929.0

New spacecraft concepts
http://www.astronautix.com/craftfam/newrewed.htm

Easy.... lets just go REALLY big:

Orion Nuclear Rocket
http://en.wikipedia.org/wiki/Project...ear_propulsion)

8 Million TONS with thrust in the meganewton range.

Nothing impresses the neighbors like shoving a ship the size of the Empire State Building into space.....