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I'm not sure if that assumption is correct. What were the specifics of the original Ares, and how do they compare with Ares V?

We'll give you that last point! 

How does DRM3 compare with Mars Semi-Direct in its original iteration?

What would MarsDirect look like with two launches per vehicle; one for the vehicle and one for the final stage?

Let's try to compare apples with apples here. Whats the mass-per-man of MD vs DRM?

It would be good if there was a site that explained DRM3 in simple terms. Does Zubrin have a good defense agains DRM3?

Edit: Why don't we lay DRM3 on the table, and we can see if there are any improvements to be made here also (I've changed the topic heading to reflect this).

Before someone else posts it first, I should also mention another thought I had: Collapsable crew quarters which fold up into the roof when more floor space is wanted. The crew area can be adjacent to the lounge to extend the living space.

Here's some preliminary thoughts I've had about improving the Mars Direct mission architecture:

1. The capacity of the Ares V can be upgraded by developing 6-segment boosters, and extending the main tank. Once 5-segment boosters have been developed, the addition of another segment should be relatively cheaper. However, such a launch vehicle will be very heavy, and will strain the load capacity of the crawler transporter. The ground-pressure of a fully-laden crawler transporter may be lowered by widening the caterpillar-track segments, and adding a layer of shingle to the crawl-way, to better spread the load.

1b. Another alternative is to develop a much larger booster consisting of 3 Ares V cores side-by-side. This means the environmentally controversial SRB's are not required. Igniting all three tanks at once guarantees the reliability of each engine before takeoff. This means that the middle tank is relatively slow burning. Also, the SRB's, though reasonably safe by themselves, are detrimental in combination with the main tank as a combined system (i.e. Challenger), and under the increased load will require careful evaluation before man-rating. The two first stage main tanks may be kerosene powered if this is advantageous.

2. A more powerful booster should allow a Mars Direct style 4-crew hab and ERV to be thrown direct to Mars with more room for mass uncertainty. However, if such a booster is able, and the final mass requirement is low enough, it would be favorable to launch the hab into a parking earth orbit, where the crew can later board and perform pre-flight checks. However, doing it this way might allow too much fuel in the upper stage to boil off, in which case a purpose built upper stage may be required, further increasing cost. Ultimately, this will probably be decided upon once the mass uncertainty (both of the mars vehicle and the booster) is narrowed.

3. To speed development if necessary, the operational requirements of all systems can be down-graded by sending a crew of 3 on the first mission. This would also allow more supplies to be sent with the Hab: More spares, science equipment, and consumables. This will better accomodate for the contingency of ERV failure on the first mission.

4. From the outset, the martian explorers should be given as many tools as possible to perform a primarily geological science mission. This is to ensure a good science return, and to keep the astronauts stimulated with new discoveries. In order to achieve a leap in science return and mental stimulation, the astronauts should be able to explore as large of an environment as necessary, perhaps and likely larger than what even a large rover may provide. Therefore, the Hab should be able to achieve long-range mobility. This can be achieved without increasing its mass by sending the necessary modifying equipment on a seperate cargo vehicle. The astronauts will then be able to fit this equipment after they have completed the initial exploration of their immediate environment. This additional cargo vehicle may also allow the delivery to the surface of any non-essential equipment that might otherwise be sent with the Hab, like extra consumables, science equipment, tools, and spares.

5. Future launch windows should allow for the launch of double and triple missions. Sending multiple missions in parallel may add a little redundancy, both during interplanetary cruise and once on the surface. The possibility of crews voluntaring to stay for longer periods on the surface should also be allowed for. If two or more missions operate on the surface at the same time, then it is possible for crews to mix, thereby avoiding conflict if there is disagreement within crews.

6. Thorough pre-testing of equipment should be of high-priority. Hopefully, this will be easier as the Mars program will not be a race, and the final deadline won't be as 'hard' as it was during Apollo. The ~2 year launch window should assist, rather than interfere, with this.
As the Mars Direct plan doesn't require space-rendezvous, most pre-testing can be done on earths surface. However, all critical systems should be tested to operate smoothly in zero-g, in case of tether failure during inbound and outbound legs.
The completed ERV should be thoroughly pre-tested, from landing to takeoff, in a mars-proxy environment on earths surface.

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Thats it for now. Feel free to add comments or contribute your own ideas here.

Why do you say only 0.05%? That seems pretty small. 2.5% failure rate would be about the same as the Shuttle, and they're still keen to put 7 eggs (no offence to the shuttle crew) in that basket.

Cool it worked. Thanks.

It reminds me of the method icelanders use to remount the huge tires they have on their 4x4's when they come off the rims: They spray a little kerosene inside the tire cavity and drop in a match. The pressure causes the tire to expand and collapse back onto the rim.

Would the liquid fuel expand into gas before or after admission into the sub-chamber?

Thanks SpaceNut. Tried it but it still doesn't remember. I'll keep trying and get back to you shortly (maybe if I reset the pc aswell...?)

The newmars.com login system hasn't worked since I downloaded some software to reset my broken Windows XP Firewall.

I've checked all the right cookie and security options but to no avail...

Any ideas?