Ares I (CLV) - status

GCNRevenger · 2006-04-11 19:49:57

I don't know, it might be beyond the skills of armchair rocket scientists... there are several combinations and questions involved...

-4X four segment SRB with 3,4, or 5 SSME?
-4X four segment SRB with 2,3,4, or 5 RS-68?

-Five-segment SRB as a future upgrade for heavier Mars ships? Perhaps to avoid the need for nuclear rockets?

-Air-start the core stage only after SRB burnout required? Or as an upgrade? Difficulty in making SSME or RS-68 air-startable?

If some version of the CaLV could be upgraded later such that you could do a DRM-III style mission in only three launches instead of six, that would more then pay for the methane engine.

SpaceNut · 2006-04-11 20:04:24

I am wondering about slush Hydrogen to slow the progress of boil off but where does it boil off to?

The problem is designing stages to be done from the bottom up rather than designing it from known payload number that we wish any particular stage to push.

GCNRevenger · 2006-04-11 20:24:15

Check this out, straight from our man in NASA when he used to work for Orbital:

http://fti.neep.wisc.edu/neep602/FALL97/lecture30.pdf

The last page especially has a list of rough-sketch "Magnum" varients, with some figures that I assume to be in pounds. Note that these do not include any help from the EDS stage for acent, so the 2X four-segment SRB with 4X SSME rocket gets 80MT, which is about what it would be for the ESAS CaLV.

On there is exactly the rocket I was thinking about: 4X four-segment SRBs with three "low pressure 650klb" (RS-68) engines hitting ~95MT to orbit on its own, or probobly the in the region of 140-150MT with the EDS stage. However, this design calls for an air-start core, which might be an issue. If it only requires three RS-68s instead of five, that would about make up the cost of one of the extra SRBs, plus make core design easier.
___________________________________________

The bigger the fuel tank, the harder it is to work with slushed fuels, since solids will settle. Even small tanks will need a stirring mechanism before and during firing probobly. The EDS tanks are pretty big, and right now we have no large-scale way of making slush H2 or engines that burn it.

GCNRevenger · 2006-04-11 21:25:25

There are other options.
How difficult would it be to place recirculation systems in orbit? Something that would allow a tankload of fuel to dock and stay in orbit indefinately, minus orbital maintainance.
At the risk of making GCNRevenger explode, its the first step towards a fuel depot. When spacex finally gets the Falcon 9 off the ground we'll be able to send up several expendable loads of fuel for much less moeny.

I am not knee-jerk opposed to the idea of a fuel depot in the long run, it might be useful later on, but I am very skeptical about including it in the "must be built, must work" catagory for early Lunar missions. It adds alot in the way of mission complexity, new hardware, and cost that I don't think its worth it. Just build a bigger rocket.

Said bigger rocket would come in handy for Mars later on anyway: if NASA is talking about increasingly radical alterations to the CaLV rocket, then if it could be improved up to ~160-170MT then that would radically reduce the cost, risk, and complexity of Mars missions later.

PurduesUSAFguy · 2006-04-11 21:58:43

My hope is that NASA chooses to go with uprated the launch vehicle rather then gutting payload. It would be a reletivley easy fix to expand the CaLVs tank and SRBs are cheap enough that going from two to four wouldn't be a cost breaker. If they start gutting the LSAM then VSE just become Apollo redux with no major capacity to put payloads on the surface.

Also, as GCNR stated, really the only thing that Mars is getting out of the current ESAS hardware is the HLV, so we might as well get as big a one as possible from the get go to make the Mars program look that much cheaper when it rolls around.

Does anyone know if the cost overrun on the Ares I is due to the switch to five segement or is it just big aerospace bloating? If the latter is the case I say ditch ATK and dump that money into COTS. 3 billion would pay for the T space CXV and the Space X Dragon.

GCNRevenger · 2006-04-12 06:35:24

"Gutting" the payload would not be a total loss, you can still build and man a Moon base, the problem is that you lose the option to go to the Lunar poles. And this is IF the EDS has a 90 day loiter, if it were cut to a more reasonable figure, the LSAM might reach the poles.

Switching from 5X SSME to 4X RS-68 would save enough money to buy those two extra boosters probably, and you might get away with the present 8.4m diameter core tank.

A big part of my support for the idea of a yet-even-bigger rocket hinges on just how much bigger it can be made; if its only like 130-140MT then its no good for Mars, its too big for a dual-launch but too small for a single-launch arcitecture. If it can be uprated to the 150MT+ region, then a single-launch mission with nuclear engines becomes practical.

Jeffy Bell does point out one idea though, skip the CLV and go with two down-graded CaLVs, one for the CEV and the LSAM and the other for the EDS rocket. This would solve the mass and boiloff problems handily, but you would have to man-rate the CaLV and forget NASA missions to the ISS. Unless Bush/Congress has a sudden change of heart about the ISS.

A big part of the SRB cost spike, if it is indeed real and not covering other components of the vehicle (J-2X development for instance), would probobly be from the change of propellant from HTPB (with aluminum and ammonium perchlorate) to PBAN (ammonium nitrate and probobly aluminum)

T/Space? They can't do anything but drop fiberglass models out from under stretch-winged Leer jets, and Elon knows how to build rockets, not space capsules, and he's a ways still from being good at launching anything.

cIclops · 2006-04-13 00:50:35

Still the pointless analysis goes on, without direct input from NASA everything is speculation. Griffin has sold congress a robust lunar exploration program with 4 crew anywhere for a least a week and the setting up of an outpost later on. This requirement still stands and he will be doing whatever it takes to make it happen, and to do it all within the budget.

cIclops · 2006-04-18 02:34:33

$28 million contract awarded Apr 17, 2006 to ATK Thiokol to continue design and development of the First Stage for the CLV

SpaceNut · 2006-04-19 08:01:29

NASA's Crew Launch Vehicle to Power Future Space Exploration

The recoverable first stage is a single, five-segment solid rocket booster powered by a reusable solid rocket motor - both derived from the current booster and motor elements that help power the space shuttle to orbit. The stage will incorporate numerous enhancements, including advanced recovery and roll control systems, designed for greater vehicle steering and maneuverability during flight. And while the first stage engines will burn the same polybutadiene acrylonitride propellant used by the shuttle's solid rocket boosters, NASA is pursuing alternative chemical propellants to increase booster efficiency and reusability.
The Crew Launch Vehicle is an in-line, two-stage rocket configuration built primarily to carry to space the Crew Exploration Vehicle - the capsule that includes the crew compartment and integrated launch abort system. The total payload capacity of the Crew Launch Vehicle is 25 metric tons. It will weigh some 907 tons on the launch pad and stand 309 feet tall.
Flight testing of the Crew Launch Vehicle is expected to begin in 2012

What ever happen to unmanned flight in 2008 followed by 2010

Rxke · 2006-04-20 06:18:17

The stage will incorporate numerous enhancements, including advanced recovery and roll control systems, designed for greater vehicle steering and maneuverability during flight....
... NASA is pursuing alternative chemical propellants to increase booster efficiency and reusability.

Gawd, why? How much will that cost, and how long will that take? Different propellants = different booster, no? So loooots of qualification testing etc. Sigh...

GCNRevenger · 2006-04-20 07:33:13

*sigh*

Looks like ATK hasn't learned any history lessons, one of the reasons why Shuttle is so ruinously expensive is because they keep on trying to improve it.

Being that the vehicle is so long though, it may need some of the changes.

Rxke · 2006-04-20 08:18:55

Some changes, sure, but what they're doing (at least it looks like it) is *not* re-using existing hardware to keep costs down, no, they'll have to all but start from scratch.

I'd have no problems w/ this, if they stuck to the old design, and do some r&d in tandem -as long as it doesn't break the bank and as long as it does not risk going down the drain, once again, by sprialling costs, tests, re-re-re-evaluations etc etc etc.

I mean, they chose the SRBs because they were tried and tested, no? Why take a step back?

I don't like the 'numerous enhancements' approach. That's a surefire way to delay stuff.

GCNRevenger · 2006-04-20 13:15:54

If you change enough of the rocket then there might not be much left to salvage in the first place...

-Thicker casing
-Different propellant and casting
-New thrust-vector nozzle
-Modified recovery mechanism
-Roll control verniers (on booster or upper?)

...etc. The old Shuttle SRB was the most reliable and safest large rocket engine in the world. If a new rocket built the same way with similar factory machinery and assembled in a similar fasion can be made, that is still better then a totally clean-sheet rocket.

SpaceNut · 2006-04-24 19:46:05

Lockheed Martin’s proposals for NASA CEV may get 787 avionics "and the use of thermal protection system (TPS) material from the US space agency’s Stardust sample return capsule, writes Rob Coppinger." Phenolic Impregnated Carbon Ablator (PICA)

Article is short does have some interesting items...

cIclops · 2006-04-26 05:36:33

Extract from Mike Griffin's testimony to the Senate yesterday

For the CLV, NASA has directed two industry teams to begin initial development of the vehicle's propulsion systems, and to develop designs for the CLV upper stage. The Agency also plans to award design, development, test, and evaluation contracts later this year. NASA is planning a systems requirements review for this project in the fall with a preliminary design review in 2008 in order for this new launch vehicle to be ready for when the CEV comes on-line.

cIclops · 2006-04-26 09:55:16

NASA CLV Upper stage RFI (March 20 2006) available here 6 MB PDF

Lots of technical details and diagrams including development timeline showing flight tests in 2011

Mars_B4_Moon · 2006-04-29 04:53:36

Mentioned elsewhere in the forum and included here for reference
Rumor from NASA Watch
According to reliable sources NASA's initial internal estimate of what it would cost to modify the current SRB used for Shuttle missions to serve as the first stage of the new Crew Launch Vehicle had been around $1 billion. That estimate has been revised up to around $3 billion.

The Vision is Collapsing
http://www.nasaproblems.com/
NASA’s Vision for Space Exploration is collapsing.

cIclops · 2006-04-29 06:42:38

The Vision is Collapsing
http://www.nasaproblems.com/
NASA’s Vision for Space Exploration is collapsing.

This argument imploded almost as soon as it was raised a few weeks ago together with the totally unsupported and now denied claim that the CLV first stage was way over budget. It seems that the media just can't let the truth get in the way of a bad story. The strategy is so obvious, bash the VSE to bash Bush.

And what a silly site that is (btw the html code seems to be collapsing too haha) .. what is the point of comparing the size of the CLV with the Shuttle?

SpaceNut · 2006-05-02 21:03:02

Well then lets not do so for NASA sets out CLV upper stage flight test timetable Trials to start in second quarter of 2011, while contract could be placed in 2008.

The CEV/CLV first and upper stage stack will be 94m (309ft) tall, have a gross take- off weight of 909,000kg (2 million pounds) and have a 25t-to-LEO payload capacity.
During the CLV’s 10min flight the first stage will separate after 131s at 195,600ft and the upper stage engine fire at 133s and burn for 463s. During this time the CEV capsule’s launch abort system is ejected. The 5.5m-diameter aluminum-lithium upper stage will be powered by a Apollo-derivative liquid-oxygen/liquid-hydrogen J-2X engine and will contain the avionics and reaction control system, providing the roll control needed for the first stage’s flight.

That makes about 4 years since the thoughts of the CEV to just getting a contract... for an upper stage booster.

GCNRevenger · 2006-05-03 08:20:11

There isn't much sense submitting requests for the upper stage until NASA is firm about the specifics of the lower stage, and knows more about the J-2X engine they want used. Building the stage itself shouldn't be hard, its just a miniature version of the Shuttle main tank, so I am not worried about the delay in assigning a contract.

One of the main ways that costs for development spiral out of control is when something has to be changed half way through development. NASA can't afford to do that.

SpaceNut · 2006-05-03 11:41:27

I started looking at some of the old stage info from
this chart and they are missing the details of the CEV engine.
They also seem to be off with regards to the burn times...

cIclops · 2006-05-03 13:04:50

I started looking at some of the old stage info from
this chart and they are missing the details of the CEV engine.
They also seem to be off with regards to the burn times...

Yes and of course those charts do not include the current CLV configuration - the 5-segment PBAN SRB first stage and the J-2X LOX/LH2 upperstage

SpaceNut · 2006-05-03 20:32:38

The chart showed the 5 segment HTPB SRB with j-2s in the second column.
Web site that talks aboutPBAN 5-seg SRB - Need Info on Nasa Space Flight forum.

It would appear with some other searches that there is a little confusion on the number of segments for the calv was intended to have dual 5 segments but when the cev weight was increased it lead to the CLV also requiring it as well..

cIclops · 2006-05-04 10:55:41

It would appear with some other searches that there is a little confusion on the number of segments for the calv was intended to have dual 5 segments but when the cev weight was increased it lead to the CLV also requiring it as well..

The CaLV was specified with 2x5 segment SRBs in the ESAS. The CLV initially had a 1x4-segment first stage that was later changed to a 1x5-segment with PBAN propellant (slightly higher ISP).

When was the CEV weight increased? AFAIK no weight as been formally specified. In fact as the diameter has now been changed from 5.5 to 5.0 metres this would surely reduce the weight. A round number of 25 mt has been given for payload capacity of the CLV, this hopefully will be less than the weight of fully fueled SM and CEV.

SpaceNut · 2006-05-04 12:51:48

The initial target weight value was put within the capability to fly on modified versions of delta and atlas but Griffin wanted to get away from the man rated issue and bumped the weight out of there capabilities. I think about late 2004.
(aka the "60 Day Study")

NASA's New CEV Launcher to Maximize Use of Space Shuttle Components

The optimum CEV would have a mass of under 9 tonnes and a crew of four or less. But Nasa put out the Mass less than 15 to 18 tonnes (the precise value to be determined in preliminary contract studies).

This was the follow up study Executive Summary (Introduction-CEV): NASA Exploration Systems Architecture Study Final Report (DRAFT) October 2005

This was when Griffin thought about using it for resupply capablity for the ISS.

New Mars Forums

Announcement

#26 2006-04-11 19:49:57

Re: Ares I (CLV) - status

#27 2006-04-11 20:04:24

Re: Ares I (CLV) - status

#28 2006-04-11 20:24:15

Re: Ares I (CLV) - status

#29 2006-04-11 21:25:25

Re: Ares I (CLV) - status

#30 2006-04-11 21:58:43

Re: Ares I (CLV) - status

#31 2006-04-12 06:35:24

Re: Ares I (CLV) - status

#32 2006-04-13 00:50:35

Re: Ares I (CLV) - status

#33 2006-04-18 02:34:33

Re: Ares I (CLV) - status

#34 2006-04-19 08:01:29

Re: Ares I (CLV) - status

#35 2006-04-20 06:18:17

Re: Ares I (CLV) - status

#36 2006-04-20 07:33:13

Re: Ares I (CLV) - status

#37 2006-04-20 08:18:55

Re: Ares I (CLV) - status

#38 2006-04-20 13:15:54

Re: Ares I (CLV) - status

#39 2006-04-24 19:46:05

Re: Ares I (CLV) - status

#40 2006-04-26 05:36:33

Re: Ares I (CLV) - status

#41 2006-04-26 09:55:16

Re: Ares I (CLV) - status

#42 2006-04-29 04:53:36

Re: Ares I (CLV) - status

#43 2006-04-29 06:42:38

Re: Ares I (CLV) - status

#44 2006-05-02 21:03:02

Re: Ares I (CLV) - status

#45 2006-05-03 08:20:11

Re: Ares I (CLV) - status

#46 2006-05-03 11:41:27

Re: Ares I (CLV) - status

#47 2006-05-03 13:04:50

Re: Ares I (CLV) - status

#48 2006-05-03 20:32:38

Re: Ares I (CLV) - status

#49 2006-05-04 10:55:41

Re: Ares I (CLV) - status

#50 2006-05-04 12:51:48

Re: Ares I (CLV) - status

Board footer