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Project Apollo - NASSP 6.4.3 released!
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16  Meadville Space Center / Orbiter / Re: Ares on: October 12, 2006, 03:37:45 PM
do you mean the OMDP Ares?  The Ares that's in The Case For Mars?  The Baker/Zubrin Ares?

That one is available at http://groups.yahoo.com/group/marsdirectproject ... it has been "beta" for almost two years, and might get rolling again just about....now.
17  Meadville Space Center / Off Topic / Re: The Space Shuttle on: October 12, 2006, 03:23:34 PM
Of the ones presented, the current CEV is the best...but...

NASA is repeating all of the same mistakes that they did with Apollo, Shuttle, and Station, but managed to avoid with Mercury, Gemini, and Skylab. Essentially, internal elements of NASA compete with each other, and their support of mission concepts ebbs and flows with how much it benefits their own team or center, and are rarely about technical issues.

With Apollo, Shuttle, Station, and Orion, NASA went to private industry with an RFP (Request For Proposals) and each of them would draw up their best ideas. By the time this RFP would go out in each case, NASA already had its own ideas. Each time, NASA rejected the potential contractors and went with their own ideas. These occasions were called:

- Apollo (Phase A)?
- Shuttle Phase A; Alternative Space Shuttle Concepts (ASSC); Low Cost Shuttle Surrogate Booster (LCSSB)
- Space Station Phase A (which ultimately dragged through several iterations from 1982 through 1993.)
- Crew Exploration Vehicle Phase A

In the case of Apollo, the contractors had no impact at all on the NASA concept, which got adopted. The General Electric "D2" was the most intriguing...Soyuz is almost identical!

For Shuttle, they got their heads handed to them by OMB, which was probably fortunate. The front runner into Phase B was technically of very high risk, and probably impossible to actually build. Of course, failure of Shuttle back in the seventies might have put LCSSB concepts on the front burner, and we'd be in much better shape today; God only knows. The contractor which had the most impact on NASA's thinking was Grumman. North American Rockwell was selected as the contractor anyway. I've noticed several decision points during the development of Shuttle, where NASA selected the worst of several alternatives (on at least one occasion, the contractor for the second worst alternative sued NASA for bias.)

For the Space Station, the contractors had a number of wildly varying ideas, none of which particularly stood out as cheaper or better. None of them resembled the current station. That was Phase A. For Phase B, after NASA selected the "power tower" configuration, the contractors submissions were all identical to the NASA configuration...so much so that the only way to tell them apart was by looking for the logos. I wonder where they got that from? Again NASA got their head handed to them because the power tower configuration was inappropriate for microgravity research. Over the next eleven years, and $8 billion (various years' dollars) the waystation function was castrated out as OMV and OTV space tugs were cancelled and the sucker was reduced to a microgravity research station. The most practical way to launch such a station is with one shot, as building stuff on the ground is easier than building it in space. That option was formally presented in 1993 and promptly rejected. The driver for every other design of the space station after Phase A was to provide the Shuttle with a manifest worthy of its capabilities, and is why Option C was rejected.

Crew Exploration Vehicle...(Funeral March, Darth Vader or Sephiroth theme optional)...

Phase A just happened, with none of the contractors (including selected Lockheed Martin) having any influence whatsoever on the NASA baseline concept, which was selected to provide a payload for Ares I, an otherwise useless booster. Both Boeing and Lockheed Martin hammered on NASA's door offering enhanced EELV options (Delta IV and Atlas V, respectively) as alternatives to Shuttle-derived boosters, while ATK (the growing company that absorbed Thiokol and more recently PSI) similarly advocated Shuttle derived stuff...even though it still builds solid motors for both EELVs. Of course, SDV stuff is owned by Marshall Space Center, which apparently had the "deciding vote." Of the Ares vehicles, the so called Ares V (named based on the final Saturn convention, which had Saturn II, III, and IV...just they never left the drawing board) is essential. There are better ways to do it (primarily trade in the solids in favor of a low cost reusable liquid fuelled replacement), but the capability is essential. The Ares I barely edges out the heaviest current EELV's, which can tweak up the performance needed (or better still, grab one of the lighter, more practical CEV alternatives.)

Contractor slighting factors:
Apollo: Bangs Head
Shuttle: Embarassed
Station: Bangs Head
CEV: Old Skool!
18  Meadville Space Center / Off Topic / Re: Hi From MarsDrive on: October 11, 2006, 10:22:55 PM
www.marsdrive.com/msrcontest (404'd earlier today Yuck!)
19  General Projects / Mars Challenger / Re: Mars Challenger Overview on: September 25, 2006, 02:20:38 PM
Atlas V 541 has been tentatively selected as the launch vehicle.  Launch mass is 4323kg, and limitations, as I had predicted from the start, are not related to launch vehicle performance.  The stack is 5.5m high, winding up just a little too big for the 5m Short fairing.  The estimated center of gravity (which is centered, since I dropped managed energy) is just a little bit outside the curve for the B-type 1154mm clamp band.  Hopefully that turns out better (I haven't mass modelled it at all, it is currently wild-guessed at 3.5m)

The cruise configuration mass breakdown is:

Cruise stage: 1496kg
Propulsion system: 225kg
Main Adapter: 200kg
Equipment Deck: 380kg
Solar Power: 131kg
Christa Separation system: 30kg
Can Separation System: 30kg
Judith Separation System: 30kg
Christa Can: 450kg

Judith Lander: 1900kg
Christa Lander: 827kg (sound familiar? Check MER Press Kit.)

Judith Landed Net Payload: 1232.9kg (includes the landing propellant tanks that get used for ISRU)
Christa Landed Net Payload: 420.0kg

Chapter 1: Introduction
Chapter 2: Launch and Cruise
Chapter 3: Landers
Chapter 4: Christa Rover
Chapter 5: Judith Booster
Chapter 6: Propellant Production
(includes care of hydrogen seed during cruise phase)
Chapter 7: Science and Planetary Protection
Chapter 8: Going Concern
(design analyses current point, expected changes for next iteration, operational organization, expected technical challenges.)

Mars Challenger's current design is frozen.  Even if pending analyses prove that it does not work, the current version will appear in the contest submission paper.

Chapter 1-3 is finished
Chapters 4 and 5 are undergoing revision
Chapter 6 is under development
Chapter 7 is aligned but not started
Chapter 8 is in the 'doodle' phase

Subsections currently in Chapters 1-5 will wind up in 8; Chapter 4 has content that will wind up in Chapter 7, while Chapter 5 has content that will wind up in Chapter 6.

I look forward to bringing it here.
20  General Projects / Mars Challenger / Re: Mars Challenger Overview on: September 25, 2006, 01:59:43 PM
Mars Challenger's Abstract is complete and submitted.  Further posts will conflict with earlier ones on mass numbers and other details.  Check the dates ot the posts, whichever one is the latest is precedent.  If it wins, development will probably resume in January, so those posts dated earlier than the end of November will apply to the contest submission.

Anyway, the Abstract:

Mars Challenger is After Columbia Project's entry into the MarsDrive Contest.  Mars In-Situ Resource Utilization (ISRU) was originally conceived by Dr. Robert in 1989 by putting together three chemical reactions in a relationship capable of producing oxymethane propellants using seed hydrogen brought from Earth and Martian carbon dioxide.

The dominant element is the return booster and its accompanying fuel plant capable of compressing locally acquired carbon dioxide for use in a Sabatier propellant reactor, which produces methane for fuel.  Water from this reaction is stored in hover propulsion system tanks until the first of the ascent tanks is empty and available for the liquid oxygen resulting from electrolyzing the water, which also recovers the hydrogen for recycling.  The relatively undeveloped closed hydrogen loop and direct carbon dioxide pyrolysis reactions have been rejected. This increases the liquid hydrogen seed requirement to nearly equal the total volume of the propellants to be used for the return ascent ( 9.066% by mass.)  The extra hydrogen is required to capture additional oxygen from the Martian air.  Excess methane, containing the hydrogen premium, is vented early during the ISRU phase while there is no room for it.  This applicability of this simplified technique is probably unique to the scale of a sample return mission and inefficient for piloted mission designs.

Mars Challenger uses two vehicles, the Judith Booster and Christa Rover, which are launched together on a common booster and cruise stage, but are landed separately on Mars near each other in Marte Vallis, where there are Amazonian era water channels.  The dual lander approach bypasses the current technological limitations of large landers while still offering the simplicity of a single launch from Earth.

Solar power is used throughout, with a small amount of nuclear material in heating units, Christa's scientific spectrometers, and the control sample sterilizers for its laboratory style experiments.  The already controversial radioisotope heat sources needed for nuclear power would heat Judith's ascent tanks, causing seed hydrogen to be lost.

Wherever possible, qualified technologies and off the shelf or derived hardware will be used to keep development and testing costs to a minimum.  Most of the landing system employed for Mars Exploration Rovers is used for Christa.  For Judith, a new arrangement of existing parts has resulted in an unexpected increase in landing performance as compared to previous missions.  Unfortunately, the long term storage of the seed liquid hydrogen has presented challenges requiring expensive new development, forcing the author to conclude that a sample return mission of any scale is not feasible on a Discovery Program budget, and unlikely on a New Frontiers budget.  This paper shows that Mars Challenger is feasible on a six year schedule and a US$1 billion class budget typical of flagship robotic missions.
21  Orbiter Mars Direct / Planning / Landing updates from E-group on: September 25, 2006, 01:50:05 PM
We have a bunch of new posts over on the E-group at http://groups.yahoo.com/group/marsdirectproject

The big picture:

- Landing on Mars needs to be utterly overhauled for piloted missions.  Using "standard" methods, the largest payload lander that can fit under a 5m fairing is about 1900kg; 8m, 5000kg; 10m, 7600kg and 12m, 11300kg.  This has big implications for Mars Direct, but far larger ones for Mars For Less, which intends to use only 5m launch fairings.
- 14 August, aftercolumbia posted a "donut parachute" concept meant to be combined with a high beta, managed energy (L/D => 0.2) aeroshell.  The intent of this (and paracones) is to reconfigure a lander from a high beta, low lift Soyuz-like configuration to a low beta, zero lift configuration emulating the Viking-like aeroshells used today.  It has been tested in simulation with a zero lift, semi-aerocapture aeroshell, an a really big ringsail parachute and found to work well, although landing accuracy and element clearance leave something to be desired (Mark Paton ran the simulations.)
- NASA (mostly JPL) is working the problem at the concept level, and developing a "Mars EDL Mission Planner's Handbook" (perhaps not formally, but it is mentioned in the abstract and introduction of a paper about the results of parametric study of five major EDL variables.)

Internet Documents (abstracts here) regarding Mars EDL found so far:

http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/38898/1/05-2473.pdf (recommended first read)

"There have been five fully successful robotic landings on Mars. The systems used to deliver these robots to the surface have shown large design diversity and continue to evolve. How will future Mars landing systems evolve to eventually deliver precious human cargo? We do not yet know the answers, but current trends tell us an interesting and daunting tale." - Rob Manning, Mark Adler (MER/Pathfinder EDL engineers)

http://pweb.ae.gatech.edu/labs/ssdl/Papers/Technical%20Papers/AAS%20GN&C%2006-072.pdf

"Near-term capabilities for robotic spacecraft include a target of landing
1 - 2 metric ton payloads with a precision of about 10 kilometers, at moderate
altitude landing sites (as high as +2 km MOLA). While challenging, these
capabilities are modest in comparison to the requirements for landing human
crews on Mars. Human Mars exploration studies imply the capability to safely
land 40 - 80 metric ton payloads with a precision of tens of meters, possibly at
even higher altitudes. New entry, descent and landing challenges imposed by the
large mass requirements of human Mars exploration include: (1) the potential
need for aerocapture prior to entry, descent and landing and associated thermal
protection strategies, (2) large aeroshell diameter requirements, (3) severe mass
fraction restrictions, (4) rapid transition from the hypersonic entry mode to a
descent and landing configuration, (5) the need for supersonic propulsion
initiation, and (6) increased system reliability. This investigation explores the
potential of extending robotic entry, descent and landing architectures to human
missions and highlights the challenges of landing large payloads on the surface
of Mars." - G. Wells et. al. (Georgia Tech)

http://www.ae.gatech.edu/labs/ssdl/Papers/Masters/AE%208900%20Report%20(no%20appendix).pdf

"The purpose of this investigation is to begin forming a dataset to be the basis of a Mars
entry, descent and landing mission design handbook for planetary probes. The premise of
the project is that Mars entry, descent and landing can be parameterized with five variables:
(1) entry mass, (2) entry velocity, (3) entry flight path angle, (4) vehicle aeroshell diameter,
and (5) vertical lift-to-drag ratio. For combinations of these input parameters, the following
trajectory information will be determined: peak deceleration, peak heat rate, heat load, and
the altitude at which Mach 2 is reached (for parachute deployment)." - Grant Wells (Georgia Tech)

http://engineering.kingston.ac.uk/space/research/papers/elieallouis/IAF03-EDLS-Allouis.pdf

Vanguard is a proposed post-Beagle2 mission to
Mars focussed on astrobiology, but also on
technology demonstration[1]. The 120 kg probe is
assumed to use a Mars-Express- type bus to land a
triad of robotics comprising a lander, a rover and 3
penetrating moles. The landed mass is around 65
kg. The mission is baselined to be low-cost with
limited power and mass requirements to be
accommodated as a secondary payload on a future
mission to Mars[2]. Here the Entry, Descent and
Landing system (EDLS) is investigated comparing
conventional methods (hard heatshield/Parachute)
to current new developments in inflatable entry
structures as demonstrated by missions such as
IRDT and IRDT2. Two systems are designed to
provide an understanding of EDLS requirements in
term of masses and volumes to land a small probe
safely on Mars. Preliminary results[3] show that,
despite the heritage, a conventional approach is
heavier than inflatable technologies. Indeed, in this
particular case, a margin of about 15 % is derived
in favour of the inflatable system. For a constantmass
probe, this means that the mass is saved from
the EDLS to the benefit of the payload. Moreover,
despite having a larger range, and longer descent, in
this case the inflatable option has in this case a
wind gust sensitivity comparable to the parachute
option." - Ellie Allouis, Alex Ellery, Chris Welch (Kingston University (UK), School of Engineering)

Note: "Inflatable Structure" means donut chute; obviously aftercolumbia was not the first to think of it.

http://www.sra.org/docs/Paulos.pdf

"RISK ASSESSMENT APPLICATIONS TO
SCIENCE AND EXPLORATION MISSIONS" - Dr. Todd Paulos, Netcom

Note: This is a projector presentation.

Something crashed, hitting send so I don't lose this


22  Meadville Space Center / Orbiter / Re: Virtual Nasa on: September 25, 2006, 12:51:09 PM
I have been witness to some legendary flame wars erupting regarding both of these on the Orbiter forums, especially with regards to VUSSP.  I doubt that VUSSP could ever "shine" the way it was being operated.  What really doesn't make any sense to me is why they keep so many secrets.  To me, if they don't help educate and discover how the real missions worked, and discover how they should work (organizationally, as a technical education can be gained by an individual), then there really is no point.  I'm expecting not everyone would agree with me (or perhaps they really were intended to be just fun...sure fooled me!)
23  Meadville Space Center / Off Topic / Re: Test on: September 25, 2006, 12:40:07 PM
 Zip Lip What? Worried Excited! Thumbs Up Yes Embarassed Shocked Crying or Very sad Mad Undecided On Fire! Film Stop Sorry Gavel Chill Pill Bangs Head Hurricane Jump Punch ROTFL :SpaceShuttle26114: High Five! Joystick Write Chained 2+2=? Not Working! Thank You!! BSD
24  Meadville Space Center / Off Topic / Re: Hi From MarsDrive on: September 25, 2006, 12:37:18 PM
That's also why I decided to call my own "After Columbia Project".

You'll notice there are a lot of different focus areas on the directory listing.  Everything from NASSP to Mars For Less, to Mars Challenger to Mercury.

I think it rather interesting that we have a "Meadville", with a Space Center that doesn't really have a physical location, and probably 99% of the amateur (and professional) space nuts Meadville SC serves have never been to Meadville. Happy
25  Meadville Space Center / Off Topic / Re: Rocco Petrone dead at 80 on: September 25, 2006, 12:31:15 PM
.
26  Meadville Space Center / Off Topic / Re: James Van Allen dead at 91 on: September 25, 2006, 12:30:46 PM
.
27  Meadville Space Center / Site News / Re: Hacked on: September 12, 2006, 04:21:25 PM
I have not identified any PMs from this site (ever) so I'm guessing that either gmail does a good job of filtering them (I only take a cursory look at the spam folder to make sure there aren't any genuine emails in there; it is very rare that there are...gmail also shows the first line of text on the list overview pages, so a legitimate looking subject line is not enough to get me to click on it.  Gmail won't resolve any external links unless I tell it too, and also doesn't run macros or attachments, means that clicking on it is harmless.)  If this site sends mail in the name of an account holder, gmail checks the header to see if the originator address according to the header is the same as the originating IP domain according to SMTP...if they don't match, off to the spam folder it goes.  That would explain if anyone has tried to send me a legitimate PM from this site and never had any indication it was received.  If a genuine illegitimate spam was sent to me through this site, I would never recognize that it came from here because I don't check all my spam headers (only so many minutes in the hour a day I spend doing email...only so many seconds in the minute I spend looking at spam...)

Terry Wilson
After Columbia Project

P.S: where did the smileys go?
28  General Projects / Mars Challenger / Judith Booster Baseline (warn: technical) on: August 08, 2006, 04:39:19 PM
I have mass numbers for the Judith Booster based on structural component, tank mass, propellant mass, and system mass estimates:

Gross lift off: 2694.3kg + sample return descent module
Stage 1: 308kg empty, net ascent (includes pressurant, but not residuals or performance margin)
Stage 1: 2127kg loaded, net ascent
Stage 2: 121.5kg empty, net ascent (includes pressurant, but not residuals or performance margin)
Stage 2: 567.3kg loaded, net ascent

Motor thrust 3405/3500N (1kPa ambient/space)
Motor Isp (m/s): 3320/3413m/s (1kPa ambient/space)
Motor Isp (sec): 338.4/347.9 (1kPa ambient/space)
(This is sligntly smaller than a Shuttle RCS thruster.)

The first stage has five motors, while the second has one.

Estimated performance to a 6675m/s delta-v mission (which is probably overkill): 162.94kg delivered to entry interface at Earth.

Estimated landed mass (includes LH2, but not landing dunnage):
Total: 645.91kg net booster, includes LH2 at 100% fill factor
Total: 634.83kg net booster, includes LH2 needed for 95% fill factor ascent propellants at 2.697:1 mixture ratio

It appears that the booster will need to be secured for landing with dunnage hard connected to some of its structure (think of those styrofoam molds your TV/computer came with in the box.)  This dunnage will need to be removed by the launch support cranes before launch.  This part is not baselined yet, but if you want an idea how much of a pain it will be, it will be comparable to Exploration Rovers (http://mars.jpl.nasa.gov ), which had 52 pyrotechnic deployments before it could roll off the lander.  One of them included securing cable and electrical harness with the lander.  And of course, how are we going to flight qualify all this?  And how much will it cost? (trying to fit $1billion budget.)
29  Meadville Space Center / Orbiter / Re: Get that Sinking Feeling? on: August 08, 2006, 04:13:17 PM
Up to the what?

 Very Happy
30  General Projects / Mars Challenger / Re: Generic Mars Ascent Information on: July 28, 2006, 12:27:10 PM
I have Falcon 9 at 1800kg to 10km2/sec2 and an ascent cost of $27million (this is for the 3.6m OD fairing.)  See www.spacex.com for more information.
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