Author Topic: A Mars Launchpad for MCT  (Read 44881 times)

Offline Ionmars

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A Mars Launchpad for MCT
« on: 05/02/2015 12:01 PM »
At this time there seems to be a growing consensus that one criterion for locating a Mars base or colony is a suitable launch site for space ships. Elon Musk has said that MCT will land on Mars, refuel, and be launched back to Earth.

The process of landing onto Mars’ surface may not be too great a problem. The rocket plume that descends to the surface with the MCT will only last a few seconds. If the landing site is mostly rock then the modest amount of sand and soil that is thrown up should scatter away from the fragile engine bells. This is similar to the situation on Earth where the proposed landing pads at LC13 are fairly minimal, basically solid surfaces. This is also the case on the Autonomous Spaceport Drone Ship (ASDS). It is the launch pad that requires many more facilities to support the space ship when it takes off.

So are there geological features on Mars that would make for a better launch pad? And how should the launch facility be designed to take advantage of these features?

On Earth, considerable time and expense goes into building a flame trench. On Mars we will have a choice of transporting the heavy materials and equipment to Mars to build a large flame trench, or alternatively, taking advantage of a natural feature that could act like a diversionary trench. The first thing that comes to mind is a rock crevice or ravine that would emulate the shape of a man-made trench. A V-shaped crevice (as seen in plan view) could possibly perform as a flame deflector.

First, a rock crevice or ravine must be just the right width so that a minimum of structural metal is required to build a bridge across the ravine and be supported on both sides. The MCT would sit on the bridge, directly over the ravine during launch.

Second, the ravine would have to be deep. Once the engines are fired the ravine must receive the methane flames and not have them reflected back onto the vehicle.

Third, the sides of the ravine must be composed of strong, un-fractured rock that will retain its strength and rigidity while being subjected to the high temperature and pressure of a methane flame. Note that the extreme low temperatures of the Mars surface will exacerbate the problem because a sudden and severe change in temperature could easily crack most rocks.

On Earth, a massive water deluge is used to moderate the effect of flames on the sides of he man-made trench. If we are to take advantage of a natural geological feature on Mars such as a rock crevice, we will have to forego the water bath and accept a certain amount of damage to the sides of the ravine. This may mean that a particular site will be used only once or twice and then moved to another position for consecutive launches.

Another geological feature that could be used as a launch pad is the edge of a cliff. A steel structure would be built on the cliff edge to support the MCT during launch and the flame would be ejected down the side of the cliff. Since the launch structure would be supported on only one side, much more metal would have to be imported from Earth to build the structure. This will mean a higher cost as compared to using a rock crevice. Also, the side of the cliff must be composed of strong, rigid stone that can withstand the heat and pressure of a rocket flame.

In the case where the sides of a cliff or a rock crevice are susceptible to shattering or crumbling during a launch, some protection may be added to protect the vertical surfaces. For this purpose one could perhaps use a series of temporary horizontal plates mounted on cables. The apparatus would look like a venetian blind with each metal “louver” in a vertical position. It would be lowered down the side of a cliff or ravine between the wall and the rocket flame during launch.  One would expect considerable warping due to exposure to the flame, so additional metal plates would be added at the top prior to each launch and the whole apparatus lowered further down the wall. Later, the warped plates at the bottom of the cliff could be salvaged and reshaped for reuse.

(Are the “venetian blinds” too flimsy? What other protective device will work?)

All this protection adds to the cost of materials to be imported from Earth for the launch pad structure, but presumably it is still less than building the whole thing out of imported materials. Note that we can’t wait for some future date for materials to be produced in Mars industries; we will need the launch pad from the very first landings.

Geologists: are there any rock crevices or ravines on Mars that can be used as launch sites? Engineers: how should we exploit these terrain features, if they exist? How would the launch pad relate to the landing sites? How about storage of LOX and methane for launches? Do we require a TEL or equivalent? Is this part of an exploration base or colony village?

« Last Edit: 05/04/2015 09:59 PM by Ionmars »
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Offline Hotblack Desiato

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Re: A Mars Launchpad for MCT
« Reply #1 on: 05/04/2015 11:06 AM »
good question.

I would take a look at the launchpads in baikonur, they have built them onto an artificial rim, so the flames can blast away in 3 directions.

Such rims are very common on mars, every crater has them (and mars has plenty of them in varying sizes). The only problem might be the water-basin in that fire-trench. I guess, the first martians won't be overly happy at using at least half their water supply in those. But since that is mostly done for sound muffling and protection of the structure, I don't see the problem of removing the water, or replacing it with sand/small rocks.


Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #2 on: 05/04/2015 12:53 PM »
good question.

I would take a look at the launchpads in baikonur, they have built them onto an artificial rim, so the flames can blast away in 3 directions.
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I hadn't thought of that. Do you happen to know how big these "craters" are, like diameter and depth?
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Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #3 on: 05/04/2015 04:28 PM »
In response to Hotblack_Desiato I found some photos of the Soyuz launch platform being constructed at Kourou in 2008 using the same general plan as Soyuz launch sites at Baikonur. If you are a member of L2 you can go to the Russian Section, Thread "Soyuz in CSG - Launch base construction photos":  http://forum.nasaspaceflight.com/index.php?topic=9078.0  Reply #2 from Jester clearly shows the launch site layout with key facilities. The launch platform is being constructed over the man-made depression with reinforced sidewalls..

If not L2 you can go to NSF Section "International Space Flight (ESA, Russia, China and others)" Subsection "Russian Launchers," Thread "Soyuz-U - EgyptSat2." http://forum.nasaspaceflight.com/index.php?topic=32406.0 Reply #15 by Artyom contains five photos, the fourth one showing the Soyuz being set up on its launch platform over the man-made "crater."
« Last Edit: 05/04/2015 05:11 PM by Ionmars »
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Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #4 on: 05/04/2015 04:58 PM »
In reviewing the photos of a Soyuz style launch facility, one salient fact jumps out at you. Building ANY launch facility that includes flame pit, launch platform, erector, fuel storage tanks, LOX storage tanks, a transporter and a loading facility is a MAJOR undertaking. Even if we can take advantage of natural features of the landscape to save some money it will require NUMEROUS trips on the cargo version of MCT to deliver all required materials and equipment to Mars. On top of that we are supposed to put all the pieces together with ROBOTS before any people arrive???

Is this a show stopper?
« Last Edit: 05/04/2015 05:05 PM by Ionmars »
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Offline RonM

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Re: A Mars Launchpad for MCT
« Reply #5 on: 05/04/2015 05:30 PM »
A flame pit won't be required. I'm sure the MCT design will take into account the lower gravity requiring lower thrust and the heat from the exhaust. It won't be nearly as bad as taking off from Earth, requiring less than half the delta V to get to low orbit.

Using a natural formation would be useful and a lot simpler than trying to build a pad. It also solves the problem of the first MCT not having a prepared pad to land on. I'm not sure land something as big as the MCT in sand is such a good idea.

The first MCT can bring a rover to build berms where needed and remove the FOD that the first landing didn't blow away. It can also set up ISRU for propellent and a radio becon for landing. Then Mars has it's first spaceport.

Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #6 on: 05/04/2015 08:19 PM »
A flame pit won't be required. I'm sure the MCT design will take into account the lower gravity requiring lower thrust and the heat from the exhaust. It won't be nearly as bad as taking off from Earth, requiring less than half the delta V to get to low orbit.
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Thank you for your information.
I must say that I'm surprised to hear that a flame pit won't be required for MCT leaving Mars.
The MCT will be a be a big vehicle; I'm thinking at least as large as an FH. If I were to extend that line of reasoning back to Earth I might believe that a vehicle half that size or less doesn't require a flame trench when leaving Earth. Could we launch a "smaller" vehicle, say an F9, from Earth with lesser launch facilities than what we have now? if so, maybe we could build the launch pad at Boca Chica really simple and save some money?

PS: What is FOD?
« Last Edit: 05/04/2015 10:45 PM by Ionmars »
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Online KelvinZero

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Re: A Mars Launchpad for MCT
« Reply #7 on: 05/04/2015 11:25 PM »
Uninformed guess, but perhaps the lack of pressure would also help on Mars? I mean the pressure from the rocket would rush away more quickly.

I have also often wondered if it would be possible to have the cargo at ground level to avoid any cranes and the rockets higher up. I guess this implies a mushroom like shape: the top is the heat shield (which might deflate for launch), the rockets are around the rim, the stalk is the cargo which is left behind on launch. Perhaps the rockets could gimbal out a bit to avoid their thrust squashing the cargo section on launch.

Offline RonM

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Re: A Mars Launchpad for MCT
« Reply #8 on: 05/04/2015 11:45 PM »
Mars gravity is 0.38 g. Atmospheric pressure is less than 1% of Earth's atmosphere. The MCT won't need as much thrust as a rocket of the same mass on Earth and the rocket exhaust is going to quickly spread away. Of course they are going to need berms to block debris from hitting whatever is near the launch pad. I guess you could build a flame trench instead of berms, but that would be more difficult.

FOD is foreign object debris.

Offline gbaikie

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Re: A Mars Launchpad for MCT
« Reply #9 on: 05/05/2015 12:39 AM »
 MCT will need a landing area as well as launch pad.

Air on Earth has velocity of about 400 m/s and would be similar on Mars. Rocket exhaust gas is thousands of meters per second. The near vacuum of mars air will not make much difference.

Earth's gravity requires a couple of gees of thrust on first stage, though at blast off you going about
1/2 gee or less in terms of acceleration but as rocket loses mass it gain faster acceleration- and needs the faster acceleration to efficiently get to orbit. On Earth it does not need this much acceleration in regards to it's second stage. So for instance the second stage of Saturn, would not have enough thrust if use on Earth as first stage, but it work fine as first stage on Mars [and probably have much more capability to lift mass as compered to MCT].
Or Mars launch vehicle would have comparable thrust as rocket designed for sub-orbital trajectory.
Or say like ICBM. Or ICBM don't need fire trenches. One has silo launches [and submarine launches].
So need something like a pad and need for landing and launch.
Though on Mars one could launch over a swimming pool  type area of water- waste water or cheap water.
« Last Edit: 05/05/2015 12:53 AM by gbaikie »

Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #10 on: 05/05/2015 07:53 PM »
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I have also often wondered if it would be possible to have the cargo at ground level to avoid any cranes and the rockets higher up. I guess this implies a mushroom like shape: the top is the heat shield (which might deflate for launch), the rockets are around the rim, the stalk is the cargo which is left behind on launch. Perhaps the rockets could gimbal out a bit to avoid their thrust squashing the cargo section on launch.

  I have also thought about the process of unloading a vertically landed cargo rocket. Perhaps one solution will be related to the facilities required at a launch pad, as follows:

1)   First, assume that MCT will be a larger version of Dragon 2 – extended. The mushroom heat shield that you suggest could be a contracting umbrella-like extension of a bi-conic or triconic nose cone. The cargo version lands vertically using retro-propulsion and is employed by the expedition sponsor to deliver materials and equipment to Mars in advance of the first humans.
2)   MCT will require a method for transporting itself to a launch pad, fueling up, and launching. On Earth SpaceX already employs a transporter-erector-launcher (TEL) to accomplish those functions. A Mars version of this (MTEL) could be designed for an additional task, which is to facilitate unloading cargo.
3)   MTEL must be designed and built in sections so that it can be compactly loaded into the cargo bay of the MCT. It will be larger than MCT so may require two MCT delivery trips.
4)   MTEL must be simple to assemble because robots will put it put together.  The robots could ride along with the MTEL sections or they could be designed as an integral part of the MTEL system.
5)   MTEL should be the first cargo delivered to Mars. As such, it must be self-unloading because there will be no other equipment to help unload (an interesting additional problem).
6)   On Earth, a TEL attaches to a rocket and carries it to a launch pad. MTEL could drive (itself) to a MCT that just landed and attach to it. It could then lower MCT from a vertical to horizontal position. Now it is much closer to the ground for unloading.
7)   If you want to unload even closer to the ground then MTEL should drive MCT alongside an outcrop or ledge of convenient height from the ground, which happens to be the same height as the hatch. Then a short ramp can extend straight across from the cargo bay hatch to the ledge. A forklift could drive cargo packages from the cargo bay directly onto Mars’ surface.
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Offline RonM

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Re: A Mars Launchpad for MCT
« Reply #11 on: 05/05/2015 08:06 PM »
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I have also often wondered if it would be possible to have the cargo at ground level to avoid any cranes and the rockets higher up. I guess this implies a mushroom like shape: the top is the heat shield (which might deflate for launch), the rockets are around the rim, the stalk is the cargo which is left behind on launch. Perhaps the rockets could gimbal out a bit to avoid their thrust squashing the cargo section on launch.

  I have also thought about the process of unloading a vertically landed cargo rocket. Perhaps one solution will be related to the facilities required at a launch pad, as follows:

1)   First, assume that MCT will be a larger version of Dragon 2 – extended. The mushroom heat shield that you suggest could be a contracting umbrella-like extension of a bi-conic or triconic nose cone. The cargo version lands vertically using retro-propulsion and is employed by the expedition sponsor to deliver materials and equipment to Mars in advance of the first humans.
2)   MCT will require a method for transporting itself to a launch pad, fueling up, and launching. On Earth SpaceX already employs a transporter-erector-launcher (TEL) to accomplish those functions. A Mars version of this (MTEL) could be designed for an additional task, which is to facilitate unloading cargo.
3)   MTEL must be designed and built in sections so that it can be compactly loaded into the cargo bay of the MCT. It will be larger than MCT so may require two MCT delivery trips.
4)   MTEL must be simple to assemble because robots will put it put together.  The robots could ride along with the MTEL sections or they could be designed as an integral part of the MTEL system.
5)   MTEL should be the first cargo delivered to Mars. As such, it must be self-unloading because there will be no other equipment to help unload (an interesting additional problem).
6)   On Earth, a TEL attaches to a rocket and carries it to a launch pad. MTEL could drive (itself) to a MCT that just landed and attach to it. It could then lower MCT from a vertical to horizontal position. Now it is much closer to the ground for unloading.
7)   If you want to unload even closer to the ground then MTEL should drive MCT alongside an outcrop or ledge of convenient height from the ground, which happens to be the same height as the hatch. Then a short ramp can extend straight across from the cargo bay hatch to the ledge. A forklift could drive cargo packages from the cargo bay directly onto Mars’ surface.

Why move the MCT to a launch pad? Launch it from the same pad it landed on.

Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #12 on: 05/05/2015 08:41 PM »
Mars gravity is 0.38 g. Atmospheric pressure is less than 1% of Earth's atmosphere. The MCT won't need as much thrust as a rocket of the same mass on Earth and the rocket exhaust is going to quickly spread away. Of course they are going to need berms to block debris from hitting whatever is near the launch pad. I guess you could build a flame trench instead of berms, but that would be more difficult.

FOD is foreign object debris.

You observations seem quite pertinent, and led me to make some changes. As you observed, Mars low air pressure and thin atmosphere would quickly disperse the rocket exhaust. But it  would also cause any FOD, especially sand particles, to be hurled even further away and with greater velocity than on Earth. So we would modify the design for the launchpad by being less concerned about the exhaust and FOD flashing back onto the vehicle and plan to protect humans and equipment in the vicinity.

This new emphasis and an earlier suggestion about using a crater leads me to this:

1) Find a crater that is about one km in diameter. This is a size that should capture any FOD from a launch pad exhaust anywhere inside the crater. Keep all humans and equipment out of the crate at launch time.

2) Note the direction of prevailing winds. If it is from west to east, then sand should accumulate on the west interior side of the crater. We don't want to build a launch pad on sand because it provides a poor foundation for launch platform pillars and because it will cause more airborne debris when launching. We can build a simple launch platform on the north. south, or east slope of the crater, especially if it has a solid rock base.

(When your pickup truck is speeding down a gravel road, the wind stream slips by on the sides of the truck but roils up on the truck bed directly behind the rear window where air pressure is lower. Dust will settle here despite your vehicle speed. This is how sand dunes build up on Earth and on Mars.)

3) The side of the crater does not have to be a cliff as I had indicated earlier. A gentle slope will  do just fine, as exhibited in the previous photos of a man-made crater/flame basin for Soyuz.

4) All other launch facilities, sorage tanks, and human habitats will be located outside of the crater and behind the launch pad.

Thank you.
« Last Edit: 05/05/2015 09:07 PM by Ionmars »
Could a Mars pole-vaulter set a new record? Not in a space suit.

Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #13 on: 05/05/2015 08:58 PM »
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Why move the MCT to a launch pad? Launch it from the same pad it landed on.
As I have learned, it will be necessary to protect people, supplies and equipment from FOD thrown away from the launch or landing pad by the rocket exhaust. The landing pad will be just a pad, perhaps located in a crater to contain the FOD. The launch pad will be a platform with a (sophisticated) hole in the middle to allow the plume to exhaust into a crater. See reply #12.
« Last Edit: 05/05/2015 08:59 PM by Ionmars »
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Offline RonM

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Re: A Mars Launchpad for MCT
« Reply #14 on: 05/05/2015 09:24 PM »
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Why move the MCT to a launch pad? Launch it from the same pad it landed on.
As I have learned, it will be necessary to protect people, supplies and equipment from FOD thrown away from the launch or landing pad by the rocket exhaust. The landing pad will be just a pad, perhaps located in a crater to contain the FOD. The launch pad will be a platform with a (sophisticated) hole in the middle to allow the plume to exhaust into a crater. See reply #12.

Okay, for a well established base, that sounds good as long as moving the MCT isn't too difficult.

I wonder how SpaceX plans on handling the first few missions? Especially the first one.

Offline nadreck

Re: A Mars Launchpad for MCT
« Reply #15 on: 05/05/2015 09:46 PM »
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Why move the MCT to a launch pad? Launch it from the same pad it landed on.
As I have learned, it will be necessary to protect people, supplies and equipment from FOD thrown away from the launch or landing pad by the rocket exhaust. The landing pad will be just a pad, perhaps located in a crater to contain the FOD. The launch pad will be a platform with a (sophisticated) hole in the middle to allow the plume to exhaust into a crater. See reply #12.

If you build that sophisticated launch pad, why aren't you landing onto it? Do you expect the traffic to be so heavy that you couldn't afford the time to land, unload, refuel and take off? Now, that doesn't mean I wouldn't have an extra pad or two in case of something taking the sophisticated one out for some reason, but before you could build this sophisticated launch pad you would have had to accurately land a few with no pads, then several on the first unsophisticated pad.  However I don't see the hole being in the middle unless it is for a 2nd cargo lander model after the base is established, I don't see the initial ones being able to land on un prepared locations without having their engines canted out to protect the engines from FOD during landing.

[edit] Also engines canted out so initial landings don't disrupt stability of surface under the lander so that it stays vertical and does not fall over [/edit]
« Last Edit: 05/05/2015 09:48 PM by nadreck »
It is all well and good to quote those things that made it past your confirmation bias that other people wrote, but this is a discussion board damnit! Let us know what you think! And why!

Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #16 on: 05/06/2015 12:15 AM »
If you build that sophisticated launch pad, why aren't you landing onto it? Do you expect the traffic to be so heavy that you couldn't afford the time to land, unload, refuel and take off? Now, that doesn't mean I wouldn't have an extra pad or two in case of something taking the sophisticated one out for some reason, but before you could build this sophisticated launch pad you would have had to accurately land a few with no pads, then several on the first unsophisticated pad.  However I don't see the hole being in the middle unless it is for a 2nd cargo lander model after the base is established, I don't see the initial ones being able to land on un prepared locations without having their engines canted out to protect the engines from FOD during landing.

[edit] Also engines canted out so initial landings don't disrupt stability of surface under the lander so that it stays vertical and does not fall over [/edit]

I can certainly understand the desirability of landing and launching on the same pad. We ought to see if we could make that work. So I have some questions about your question.

First, refueling prior to launch. If we put the (ISRU) LOX and methane producing equipment right next to the pad then it is just a matter of attaching a hose from one to the other prior to launch. But would this procedure not introduce a level of danger to the ISRU equipment during landing?

If we decide to put some distance between the launch and landing (L/L) pad and the fuel-producing equipment then we need to carry the fuel to the MCT while it is on the pad. This requires (two) wheeled tankers to carry LOX plus methane to the launch site. The tankers would remain on site during countdown to top off the on-board tanks as the propellants evaporate. The mobile tankers would now be subject to risk during launch but could remain away from the pad during a landing.

 As you may see in Reply #12 I would like to carry around an empty MCT using a Mars-adapted TEL that could also be used to unload cargo. In either case we may need to transport wheeled tankers from Earth to Mars before we can launch one MCT back to Earth.

Incidentally if we can make the L/L pad work for Mars, could we make it work on Earth? I never took the term return-to-launch-pad (RTLS) literally but maybe I should.
« Last Edit: 05/06/2015 12:36 AM by Ionmars »
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Offline nadreck

Re: A Mars Launchpad for MCT
« Reply #17 on: 05/06/2015 12:33 AM »

I can certainly understand the desirability of landing and launching on the same pad. We ought to see if we could make that work. So I have some questions about your question.

First, refueling prior to launch. If we put the (ISRU) LOX and methane producing equipment right next to the pad then it is just a matter of attaching a hose from one to the other prior to launch. But would this procedure not introduce a level of danger to the ISRU equipment during landing?

I don't see having the ISRU equipment near the pads but I think it would be a lot less infrastructure cost to bury insulated piping in two trenches that runs from outside the crater to the inside. I am not thinking this pad happens until we have had at least a dozen cargo flights land and it will be for when we have set up a permanent (but expandable) ISRU facility.

If we decide to put some distance between the lainch and landing (L/L) pad and the fuel-producing equipment then we need to carry the fuel to the vehicle while it is on the pad. This requires (two) wheeled tankers to carry LOX plus methane to the launch site. The tankers would remain on site during countdown to top off the on-board tanks as the propellants evaporate. The mobile tankers would now be subject to risk during launch but could remain away from the pad during a landing.

As you may see in Reply #12 I would prefer to carry around an empty MCT using a Mars-adapted TEL that could also be used to unload cargo. If we need to transport wheeled tankers from Earth to Mars before we can launch one NCT back to Earth we may be extending the equipment pre-deployment period before the first humans arrive.

In another instance, if we tried to carry the MCT to the fuel loading station and then to the L/L pad then MCT would be different from other rocket vehicles in being able to be carried around while it is full of fuel (not likely).

So even with the low Mars gravity you are talking about a road that has to support say 23t of empty MCT 60t adjusted for 0.38g at mars and I can't imagine the TEL weighing less than the MCT so we need something that is about twice the rated capacity of your average gravel road. I believe digging 2km trenchs for the propellant pipes will be cheaper in terms of total mass and energy required.
It is all well and good to quote those things that made it past your confirmation bias that other people wrote, but this is a discussion board damnit! Let us know what you think! And why!

Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #18 on: 05/06/2015 01:01 AM »
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I don't see having the ISRU equipment near the pads but I think it would be a lot less infrastructure cost to bury insulated piping in two trenches that runs from outside the crater to the inside. I am not thinking this pad happens until we have had at least a dozen cargo flights land and it will be for when we have set up a permanent (but expandable) ISRU facility.

So even with the low Mars gravity you are talking about a road that has to support say 23t of empty MCT 60t adjusted for 0.38g at mars and I can't imagine the TEL weighing less than the MCT so we need something that is about twice the rated capacity of your average gravel road. I believe digging 2km trenchs for the propellant pipes will be cheaper in terms of total mass and energy required.

Good point.
 
If we are to dig a long trench and unroll two long pipes into it we certainly would want to keep the length of that trench at a bare minimum required for safety. Two km is much longer than I would have guessed. If we find a natural berm to separate the L/L pad from the ISRU equipment could we reduce that to say, 500 m?

Incidentally the cryogenic liquids will be easier to keep cold in Mars almost cryogenic subsurface temperature than it would be on Earth.
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Offline Ionmars

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Re: A Mars Launchpad for MCT
« Reply #19 on: 05/06/2015 03:51 AM »
Okay, so here is the plan so far, as completely revised from the introduction:

1)   We will not have a launch pad with a flame trench such as we construct on Earth. Rather, we will utilize a landing and launch (L/L) pad, which will be simply a preselected site on Mars surface, at least for the first few landings.

2)   The site will lie within a relatively small crater, about 1 km diameter. The purpose of the crater is to contain FOD that is hurled away from a rocket flame during a landing or launch event. This provides protection for equipment located outside the crater.

3)   The specific L/L site within the crater will be a naturally occurring area of flat rock or hard, consolidated material that will minimize flying FOD during a launch or landing.

4)   The L/L area could be located 100 m from a crater wall or in the middle, 500 m from the nearest crater wall.

5)   An ideal crater should have one low-lying wall segment for easy transport of materials and equipment from the L/L area over the crater wall to another site where materials, ISRU equipment and habitats will be located (the “Base”)
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6)   The Base will lie close to the crater rim, which acts as a natural barrier to shield the Base from L/L activity.

7)   To refuel MCT for launch, a trench will be dug from the Base LOX and methane producing equipment over the crater rim and into the L/L area. We will lay two pipes in the trench to deliver propellants to the L/L area.

NEXT:
a) What equipment will we deliver to Mars to dig a trench and lay pipe?
b)  Will MCT aim to land in the same exact location each time or at different locations within the L/L area?
c) If we want to minimize equipment we will not use a TEL, but a smaller piece of equipment to load propellants from the pipeline into the on-board tanks. What will this look like?
« Last Edit: 05/06/2015 11:43 AM by Ionmars »
Could a Mars pole-vaulter set a new record? Not in a space suit.

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