Crew Exploration Vehicle:In depth discussion and analysis of design

Hopefully there are some people around here who are interested in the CEV design that is being planned to fulfill Bush's space requirements. Basically, NASA has put out a bid for a series of spacecraft that can, through modular design, be connected to boosters and supply modules that would be appropriate for lunar, near earth asteroid, and mars (and beyond) missions. The idea is to create a type of standard exploration ship for the next generation.

Here are some links that show what Boeing has proposed up to this point:

CEV with Translunar Insertion Stage:
boeingmedia.com...

Interplanetary CEV:
boeingmedia.com...

Lunar space station to be used for interplanetary assembly:
boeingmedia.com...

I'll come back later with Lockheed's stuff (unless someone else wants to post that info now... please go ahead). Hopefully this thread can become a usefull CEV resource.

Here is the NASA site that deals with the CEV design:

exploration.nasa.gov...

The overall space exploration program involving the CEV has been placed into something called Constellation.

As this chart shows, Project Prometheus and the Jupiter Icy Moons orbiter have also been placed under Constellation as part of the nuclear propulsion development program:

exploration.nasa.gov...

Though a lunar flight wouldn't require anything but chemical rockets, the point behind the CEV is that it can be used for interplanetary flights when attached to a more advanced drive system.

We would have a vehicle capable now if Nasa didn't cancel programs moments before there operational.
Like the X-33 & X-34

The logic behind the CEV-derived stuff is that it's modular and so different equipment combinations can be used for a variety of missions. The CEV is intended to be used for exploration beyond Earth.


rocketplane/gliders like the space shuttle and X-33 only make sense when used to ferry equipment from the ground to orbit. On a journey to Mars or the moon, wings (and everything thing else that makes a spaceplane a plane) are useless and amount to dead mass that you still have to push. Developing another spaceplane type craft would only have kept us away from Mars/returning to the moon for another generation.

I think the CEV

1. Should be built in orbit or possibly out of a small asteroid. Football field sized asteroid or maybe a little bigger.

2. Be designed to spend years in deep solar space if needed.

3. Be built of framework design so you can add/remove engines, sensor equpment, crew areas etc.. with upgrades.

4. Have the ability to capture satelites like mars global surveyor so it can be reused/repaired etc.. for continued use or maybe moved to a different planet or assigned a new mission. Ability to grab earth satelites that really no longer have a use and refuel/reuse them for use around other planets.

5. All new exploration probes should be built with reuse in mind.

6. Have return to earth vehicle and of course 2 landers attached.

7. Instead of a one shot deal, overall it should be designed for continued use like modern Navy ships.

8. Should include the best artificial gravity capabilities that we can put on it.

9. Have Nuclear and Solar power capabilities.

10. Should spend around 200 to 500 billion on its construction. (lets do crew exploration right the first time).

11. Be capable of supporting colonization efforts of Moons/planets/asteroids.

12. Oh and we should build 2 or 3 not just one.


[edit on 10-7-2004 by Xeven]

[edit on 10-7-2004 by Xeven]

Xeven, I gotta say that what you want is the opposite of what this program is supposed to be... and I believe you're line of thinking reflects the mistakes NASA has made over the last 30 years. Here's why, point by point:

1."Should be built in orbit or possibly out of a small asteroid. Football field sized asteroid or maybe a little bigger"
Schemes to build giant spaceships in orbit have contributed to us NOT going to mars or returning to the moon. Ultimately, they revolve around lifting heavy components into space multiple times... all at great cost. Assembling these parts also requires multiple missions and time. Just think about the time and money it has taken to (partially) build the ISS compared to the same for Skylab in the 70s.

Yes, eventually multiple components will have to be put together in space, but the point of the CEV idea is that it won't require huge 'dockyards' to build.

As for the asteroid idea, um, inorder to build a spaceship out of an asteroid you'd have to get to the asteroid first -- which is the whole point, really, of the CEV.

2."Be designed to spend years in deep solar space if needed. "
Ultimately, CEV components will be used for deep space missions, but building something, now, that can support humans in space for years would mean that both long terms and short term goals would be delayed because we were trying to 'leapfrog' and do the long-term stuff first.

3." Be built of framework design so you can add/remove engines, sensor equpment, crew areas etc.. with upgrades"
The CEV itself is supposed to be a modular component that can be used within a larger system. A CEV flight to the moon would use conventional rockets, for instance, while a mars flight would involve a CEV and habitation module being fitted to a variant of a nuclear rocket.

4."Have the ability to capture satelites like mars global surveyor so it can be reused/repaired etc.. for continued use or maybe moved to a different planet or assigned a new mission. Ability to grab earth satelites that really no longer have a use and refuel/reuse them for use around other planets."
Probes are usually designed for specific missions, with specific capabilities in mind. I fail to see how flying to Mars to retrieve and old probe, flying back with it, rebuilding it from the frame up, and then relaunching it would save money when compared to just launching a new probe.

5."All new exploration probes should be built with reuse in mind. "
There's no point in this. By the time something like Cassini would return to earth all of its equipment would be obsolete or damaged. All you would be refurbing, then, would be the relatively inexpensive frame.

6."Have return to earth vehicle and of course 2 landers attached."
Well, obviously the idea is to return to earth...

7." Instead of a one shot deal, overall it should be designed for continued use like modern Navy ships."
Navy ships don't reenter the atmosphere at thousands of miles per hour. As we learned with the shuttle, turning a vehicle around and flying it again takes months of inspections and repairs. Keep in mind that these 'one shot deals' might last weeks or months, or even years, anyways. Also, what percentage of the shuttle's mass is dedicated towards making it reusable?

8."Should include the best artificial gravity capabilities that we can put on it. "
There's no need for this on a moon voyage. A mars mission will be shortened by using a nuclear engine. Other than that... installing a 'hamster wheel' in the ship would just add mass and cost.

9.". Have Nuclear and Solar power capabilities. "
I suggest you read the links I provided.

10."Should spend around 200 to 500 billion on its construction. (lets do crew exploration right the first time)"
You will never see this, then. Inflated costs are what has scared congressmen away from supporting space exploration. A half trillion dollar space cruiser is really no better, as a spaceship, than a capsule.

11."Be capable of supporting colonization efforts of Moons/planets/asteroids."
In the long run things like Constellation Systems might make this happen, but right now we have to get there first.

12.". Oh and we should build 2 or 3 not just one."
Bush wants to build dozens of these capsules and supporting modules.

Xeven, I suggest that you read the resources that have been linked to already. The CEV is not supposed to be a giant battlestar galactica type thing... it's supposed to be an affordable, modular system.

This article summarizes the latest word from NASA:
www.upi.com...

Basically, as has been said before in this thread, they want a design that can be later used as a component in a Mars mission (they want one generic exploration vehicle type that can be fitted to different components for different missions).

Of interest: NASA intends to have a 'fly-off' between two experimental models from two contractors (as in a military procurement competition). So... one can assume that both Lockheed and Boeing will eventually get to the point where they have completed actual spacecraft (would the 'losing' design be sold to private investors as a way to recoup company financial losses?).

I haven't added any photos yet...


The (current) Lockheed concept at launch:




The (current) Boeing concept in its moon configuration:





The Boeing concept as one module in a Mars ship:




The (current) Boeing design is clearly inspired by the Apollo program.

Here's a new article on the CEV that goes over the 'spiraled' development program that NASA is envisioning:

www.space.com...

"CEV is part of an "exploration infrastructure", Young said, akin to the railroads that enabled U.S. expansion westward. He also likened it to America’s Interstate Highway System.
"What Project Constellation and CEV are about is creating a capability in the long-term that generates an exponential return in science," Young said."

I think it's important to note that NASA isn't just investing in a 'new ship'... it's trying to set up a modular space transportation system that can be expanded and adapted to future demands.

CEV design, love the idea for discussion and so I add my own:

home.earthlink.net...

My thought was to modularize the Space Shuttle, with what I called CEV;

Crew Escape Vehicle, aka Crew Experiance Vehicle, aka Crew Exploration Vehicle

I saw the Shuttle design based after what I use to build as a child in model car's with AMT 3 in 1, where you could build a standard car, Hot rod or customize version of the same car.

With a CEV design attached to the shuttle main computer upgrade would only ground the cev while the rest of the vehicle is used to service mission's on the calendar. I also saw what I call the Nascar or Indy solution that when in either of these races during qualification the car was to lose an engine, notice that they don't pack up and leave. They merely take the engine out and replace it to get qualified and into the race. We need a engine section that is just as the cev able to be removed from a leak that could take weeks to find and replaced quickly with another tested assembly and keep the mission on time and in the race.

Having this type of cev opened the door to a Lunar design based on old movies such as "Rocket Ship X" with landing gear attached to the bottom section, here we have rockets and landing gear, on top of that sits a round cylinder with the bottom section having an airlock for entering and exiting. Above that a storage section for needed life support for the trip and lastly above that living and planning section. I also saw a draw bridge design on how we would exit this craft. At the base of this bridge would stick out like a tongue, then pivot and unfold to the ground while at the same time have hand rails pivot up for the crew to grasp. The CEV would attach on the top of this and have the computers and communication.

Currently we launch a shuttle with 2 srb's yet I'm seeing 3 in my dreams, Why so we can take into orbit that which we are currently throwing away, the External Tank. Using this we can start on a space station that is not in low earth orbit and learn some real solutions to the effects of space or send to the moon for living quarters needed to explore it for any real science or collection of Helium for new fuel to get us into the 23rd century. Besides I'm not happy with nasa throwing away 30 million dollars spent on the external tank when with a little more imagination we might find a way to get it into space and recyle it for another purpose, Space Station, Lunor Outpost?

Michael

Ark-Angel
Why so we can take into orbit that which we are currently throwing away, the External Tank. Using this we can start on a space station that is not in low earth orbit and learn some real solutions to the effects of space or send to the moon for living quarters needed to explore it for any real science or collection of Helium for new fuel to get us into the 23rd century. Besides I'm not happy with nasa throwing away 30 million dollars spent on the external tank when with a little more imagination we might find a way to get it into space and recyle it for another purpose, Space Station, Lunor Outpost?

ahg, i'm sick of always hearing that we should use the external tanks rather then letting them burn up in the atmosphere. It costs around 550 million to 1 billion for every shuttle launch, that would go much higher if you wanted the external tank to get into Low Earth Obit. At launch the shuttle uses all its rocket engines to get going, but the 3 smaller rockets on the shuttle itself are at 50%, then once the 2 big external rockets are jetisoned it changes to 100% and then the big external talk is jettisoned, it has to ride with the shuttle a little ways just to get high enough so it will burn up and not fall and take out a house. To get it up to around the ISS level it would take more fuel, the shuttle could carry enough to do so but it would need more tanks, which would shrink its load capacity even more. And if you planned on having the tank be joined together in space that would take a long time to accomplish, not to mention that the tanks would need a airlock on bothsides of it so they could be joined, and the inside would have flamable fumes inside and be metal, they would be completely empty, and of course the airlocks would add weight, or if you wanted a tiny window on each tank would add morew cost and weight...there are just SO MANY variables that its rediculous to even consider doing that.

The current system is is fine, after all...Its going to be put to sleep in half a decade. You also said something about using the tanks on the moon for living space or helium tanks...are you kidding?!, I wont even get started on that...Its a very dumb Idea...need I really say more?

Originally posted by Murcielago
ahg, i'm sick of always hearing that we should use the external tanks rather then letting them burn up in the atmosphere.

Sorry to hear your not feeling well.

This actually started back in 1980 with Nasa engineers wanting to take the ET into orbit. As I understand it we are actually taking it up 98% of the way and using some fuel to nudge it down. As I stated in my dream 3 not 2 srb's to get this up and going. Also I don't see the 3 main engines on the shuttle but a different configuration for more fuel to move around. What I saw was a different single rocket attached to the bottom of the tank. Using the 3 srb's to get this moving and then on the way up ignite the main tank rocket to get into orbit.

Windows don't need just a HDTV with a camera on the skin.

Hope you feel better,

Michael

huh? Are you just describing a damn dream you had?

Originally posted by Murcielago
huh? Are you just describing a damn dream you had?

I believe that is what I have posted. Don't all things start as dreams? Dreaming of flying two brothers made it happen. Dreaming of a better shuttle that is modular is just a dream at this point, Apollo started as a dream to walk on the Moon.

I would prefer not going backwards in design, either improve what we have or come up with a whole new DREAM, one that will captivate the entire country.

Michael

Here are some excellent diagrams of the Lockheed proposal:
en.wikipedia.org...:CEV_Lockheed_Martin.jpg#file

en.wikipedia.org...:H_lockheed_cev_050503_02.jpg

I can't help but wonder if these are based on secret spaceplanes that are already in existence. The resemblance to various artworks of 'future' warfare that have been commissioned by the USAF is uncanny. It would certainly explian how the new NASA director feels confident about moving up the timeframe for the CEV's first launch.

Capsules make more sense than lifting bodies; sending useful payload into orbit rather than dead weight. Modularity makes a lot of sense as well, allowing for the tailoring of componants into different craft for different missions. I think this is what Mike Griffin has in mind:

www.safesimplesoon.com/media-images.htm

A better, safer, cheaper idea for manned flight is what Rutan is working on:

www.transformationalspace.com.

The best idea is to leave people on the ground and let nanobots do the job, but I won't start that fight again.

NASA's big announcement is coming today:

"Aspects are somewhat vintage Apollo in approach, but with numerous technical twists. For example, a four-person lunar expedition crew would make use of a Crew Exploration Vehicle that is outfitted with solar panels. The astronauts would rendezvous in Earth orbit with a pre-launched Earth Departure Stage, and then make the outbound voyage to the Moon.

"Once in lunar orbit, all four crewmembers would ride down to the Moon in a lander. They would depart the Crew Exploration Vehicle, putting it in autopilot mode as they spend seven days on the lunar surface."

from:
www.space.com...

Imagine, if you will, a profile wherein the capsule rests atop the existing shuttle external tank and where the shuttle main engines are located beneath the tank (with the solid-fule Thiokol boosters still on the side).

This configuration will have many advantages:
1) The main booster system has already been designed and testes extensively.
2)Production lines are already set-up for the booster components
3)The more dangerous aspects of the current shuttle design (namely the risk of hitting tank debris) are marginalized by putting the crewed component atop the stack.
4)The capsule system will probably be based on the old Apollo design, which never experienced a failure during reentry.
5)Many of these production lines/design centers are in areas ravaged by Katrina, which deflates the 'we can't do this because of the poor people' argument of the anti-space lobby.

For further reading:
www.nytimes.com...

Contrary to popular belief the external fuel tank of the space shuttle is not just a pair of open cylinders surrounded by an aerodynamic shell. The inside of these cylinders contain structures called slosh baffles. The slosh baffles prevent the liquid fuel from sloshing around inside the tank and causing a stress failure. These baffles would have to be removed to obtain any kind of useful space in the tanks.

NASA un-manned heavy lifter
This would be used to place the lunar orbiter/lander in space.

NASA CEV and it's launcher
CEV would look different but this is how it would but launched into space, on top of a Saturn 5 type of rocket. Then it would hook-up with the lunar orbiter/lander and head for the Moon.

How the CEV will return: The CEV would will re-enter Earth atomsphere, then once it got through the bad stuff it would shed it's heat shield, deploy parachutes and airbags, and land somewhere in the American west (Edwards AFB?) A landing at sea is a back up plan.

FAA give Liftport clearance for Space Tether