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#26 2023-11-25 09:13:09

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 9,267

Re: Inter-settlement transportation on Mars

How NASA keeps Ingenuity going after more than 50 flights
https://phys.org/news/2023-11-nasa-inge … ights.html

The Helicopter concept is proven to work, it might not lift such a large payload but could become important for transport of small important material or light wight essential medecine or goods, rotorcraft or rotary-wing aircraft is a heavier-than-air aircraft. On Earth unfortunately humans are still killing humans over disputes, new designs come as drones have hunted down and attacked a human target. There might be new designs suggested fopr offworld colonies perhaps a network of wings as Drones fly mixing Tandem rotors, multiple rotors in Star shape layouts or Transverse and Coaxial. Drones often use multi-rotors or the quadcopter or quadrotor design, two rotors turn clockwise and two counter-clockwise, there are also hexacopters and octocopter. NASA / JPL have stated  the feats of Ingenuity are roughly equivalent to a helicopter flying at 34,000 m (112,000 ft) altitude in the atmosphere of Earth.

https://mars.nasa.gov/technology/helicopter/#Flight-Log

The Rotocraft design will also fly on Titan.

costs for Rail on Earth?

Transport Minister: Greece's entire railway network fully restored by 2025
https://www.tornosnews.gr/en/transport/ … -2025.html

Hydrogen train goes on high plain in Spain
https://www.railjournal.com/news/hydrog … -in-spain/
However, this second trial will be performed entirely at altitudes between 1079m and 1061m along a 94km section of line, in order to test the train’s performance further

the Japan more Rover missions on the Moon

Japan's ispace unveils micro rover for its 2nd moon mission
https://www.space.com/ispace-unveils-pr … nd-mission

Last edited by Mars_B4_Moon (2023-11-25 09:24:22)

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#27 2023-11-26 12:09:26

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,460
Website

Re: Inter-settlement transportation on Mars

Flying on Mars must deal with "air" density that is factor-100+ lower than Earth,  when gravity is only factor-2.63 lower than Earth.  That means for the same effect at the same angle-of-attack,  any aerosurface must see approaching wind speeds about factor-6-to-7 higher than we use on Earth.  That applies to the wings of airplanes and to the rotor blades of helicopters.  The only way to reduce that is to lighten the wing or disk loading.  You are looking at transonic to supersonic landing and takeoff speeds on Mars for any sorts of airplane designs.  Totally unsafe to attempt.

I know the Ingenuity helicopter is working on Mars.  It is very tiny,  and carries no payload at all.  The square cube law says scaling up  structures produces heavier results as dimension cubed,  but strengths scale up only as dimension squared.  A scaled-up Ingenuity would not be able to fly,  even at no payload.  Besides,  to get around that to any extent,  you'd need tip speeds around Mach 6,  with tremendous noise,  and tremendous vibrations from unsteady shock-separation phenomena.  Even if you could make it work at all,  fatigue life would be very short.

"Lighter-than-air" works by differences in density,  lower inside the gas bag,  and higher outside.  The buoyancy force is the gas bag volume times the difference in densities.  Densities are factor-100+ lower on Mars.  So the buoyancy forces are factor-100+ lower.  Despite the lower gravity,  you would need enormous gas bags to lift very tiny payloads indeed,  mostly because much of the buoyancy goes to lifting the gas bag envelope itself.  The bigger it is,  the thicker it needs to be,  in order to be strong enough,  and eventually you reach a point where there isn't enough buoyancy to lift the envelope,  much less any payload.

Edit update 12-24-2023:  you figure this as the difference in weight densities,  not mass densities.  So what matters is the difference in mass densities at Martian pressures and temperatures,  multiplied by the acceleration of Martian gravity.  That is somewhere near 30-40 times less buoyancy potential than what you are used to seeing here on Earth.

That pretty much leaves only suborbital rocket travel for moving time-sensitive stuff (like people) long distances on Mars.

GW

Last edited by GW Johnson (2023-12-24 10:44:35)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#28 2023-11-27 04:16:06

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,434

Re: Inter-settlement transportation on Mars

Meridiani Planum appears to be rich in hematite spherules, which present one of the best iron ore resources on Mars.
https://en.m.wikipedia.org/wiki/Meridiani_Planum

Interestingly, the high phosphorus content of rocks also suggests that this region will be rich in uranium and thorium.  These two will be important energy resources on Mars.  But Meridiani Planum is a long way from Cerberus Fossae, which is the region of Mars where geothermal energy is most abundant and where we may find the vital resource of liquid water.  This would be the best place to establish an early base, which will eventually grow into a colony.  The two regions are on opposite sides of the planet.  As Martian population grows, there will be increasing interest in linking these two areas by roads.

On Earth, large igneous inclusions are associated with deposits of nickel, copper, titanium, iron, platinum, palladium, and chromium.
https://en.m.wikipedia.org/wiki/Ore_resources_on_Mars

The closest LII to Cerberus Fossae is Elysium.

As the Martian colony grows, the raw material requirements from these areas will grow.  All are within the northern hemisphere and all border the northern plain.  The plain itself is the easiest location for roads, as its topography is relatively flat and the plains are dominated by deep, fine regolith deposits suitable for road construction.  I can forsee the Martian colonies constructing a ring road around the edge northern basin early in the colony development.  This road will have numerous spurs leading to important sites.

The south will probably remain undeveloped for a long time.  Topography makes in difficult to access and the northern plain is richer overall in water.  The main target for human colonisation will be the northern hemisphere, in areas bordering the northern plain.  These are the most valuable lands to begin scouting.

Last edited by Calliban (2023-11-27 05:35:10)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#29 2023-12-11 17:56:38

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 9,267

Re: Inter-settlement transportation on Mars

We even had discussion of Cattle farms


'Chinese firm’s methane-powered rocket sends satellites into orbit'

https://www.dawn.com/news/1796631

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#30 2023-12-23 08:35:54

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 9,267

Re: Inter-settlement transportation on Mars

In a recent article Dr Zubrin suggested orbiters, drillers, highly capable helicopters, and possibly balloons could be of better use than funding of a very expensive Mars-Sample-Return mission which is eating up a lot of NASA's budget and going nowhere for now.

Rovers are great but for now don't seem to cut with with distance over period of time, Opportunity’s feats of distance are impressive they beat the old Soviet Moon Rovers. However the Rovers can take years to travel a few miles and even the Russian Lunokhod 2 rover took months to drive miles on the Moon.

I'm not sure how far the Rovers traveled maybe 25-26 miles say 40-42 km, but if these were New York City it would take them years to cross blocks and bridges and streets and most of the city would remain unexplored...its somewhat of an unfair analogy since the Rovers have to face conditions on Mars and avoid rocks etc but there has been only so much travel a Rover can do, the Plane or Balloon may cross something the size of the USA in days or hours.

Mars has some kind of magnetic field which can be of benefit to future colonists but we know little about it, the field is low so satellites are not good to study it on Mars, the magnetosphere is weak and patchy, it is calling for a 'Balloon' or some type of flying type mission.

nicknamed Ginny the NASA JPL Helicopter has shown flight can be used as transport a small item or small cargo on Mars

NASA’s Ingenuity helicopter set a new flight distance record on Mars
https://www.popsci.com/science/mars-ing … ht-record/


A paper was shared some time back before the Helicopter flew but 10 G's seems a bit much even if they have experienced High-g training we do not know the conditions human bodies will be in on Mars, there was an idea for a rocket-powered Mars glider which carries three astronauts. Spaceship / plane wings were inflatable and the wingspan was 60 m, the spaceship / plane will take off under methalox rocket power

A human might pass out at a lower 4 Gs, a roller coaster can go higher but its manageable because as its a short event and lasts just a few seconds. Fighter pilots are trained and wear suits and may have to endure up to 8 or 9 Gs

'Shocking video shows what it's like for a human to experience 9Gs of force'
https://www.unilad.com/technology/shock … e-20221118

One person said: "So many people passing out at 6g and this guy is laughing and making jokes at 9. What a beast."


MAVRIC Flight Profile
https://web.archive.org/web/20231223134 … worthy.pdf


From a link SpaceNut shared

https://www.mathscinotes.com/2012/10/ea … e-to-mars/

On Earth, we usually talk about pressure at sea level. Mars does not have an ocean that we can use as an altitude reference. The Wikipedia gives two points of reference for the atmospheric pressure on Mars:

    Peak of Olympus Mons: 30 pascals (0.3 millibars)
    Hellas Planitia: 1,155 pascals (11.5 millibars)

This is quite a range of values. The atmospheric pressure on the surface of Mars has dynamic range of 38.5 = 1155/30. To compute the dynamic range of the Earth's surface pressure, let's use the following two points:

    Peak of Mount Everest (8,848 meters above sea level): 33,730 pascals
    Dead Sea (423 meters below sea level): 106,200 pascals

This means that the dynamic range of air pressure at the Earth's surface is only 3.14 =106,200/33,730. We see that the dynamic range of air pressure on Earth is much less than we would encounter on Mars.

Let's find the altitudes on Earth with the same atmospheric pressures as Olympus Mons and Hellas Planetia.

You don't make a farm on the top of Mount Everest, you don't test a Snow Mobile in the Gobi or Sahara Desert, Patagonian Desert, you won't test a Truck designed for some Sand Dune rally at the desert at a location like the North Pole or South Pole, you won't drop a Titan Saturn Submarine on a patch of rock where there are no seas and lakes, to begin your flights of various Balloon or aircraft plane you will probably pick ideal locations where conditions are suitable. There is a lot of area to cover if we are crossing from one colony to another on Mars, to compare with Earth the  Length of the United States is 2,800 miles wide or 4506 km when measured horizontally from the eastern seaboard to the west coast, Hellas measures about 7,000 km (4,400 miles) across. The atmosphere we will be working with will be close to 30.125 km = 98,350 feet not '0.006 atm pressure' anyone writing up 2, 4 or 10 pages of flying a Balloon at this number is wrong, it doesn't prove anything about if flying on Mars is possible or impossible they can also write up figures and make a graph for flying in 0.001 atm 1.01 mbar 0.002 atm or 2.02 mbar 0.003 atm or 3.03 mbar can also provide equally as useless information if instead we are using Hellas as a base.

Mars has very uneven topography and its atmosphere is uneven and variable depending on time of the day and Martian year. We have talked about this many times before and I am not sure why it is not getting into people's heads, when people run they math they keep using an old number that is not much use for Hellas Planitia or Hellas Basin for example maybe they are pulling old atmosphere numbers from texts books or the internet. You won't be flying from the Mons or Montes, but you will probably Not be doing your first flights from Martian highlands, the ideal place is the Basin or low lands, lower lying areas the low regions of Amazonis and lows of Chryse Planitiae, the low lying Valles Marineris stretches, Argyre Basin is low but it is not as deep as Hellas Planitia or Hellas Basin for example is as deep as Mount Everest is high it is also massive size, bigger than Australia about the size of the USA, it is a large distance to travel and the Rover will not do it.

Atmospheric pressure at Hellas basin on Mars is 12.4 mbar 1240 Pa or 0.18 psi during winter.
https://planetary-science.org/mars-rese … tmosphere/

Compared to Earth, the atmosphere of Mars is quite rarefied. Atmospheric pressure on the surface today ranges from a low of 30 Pa (0.030 kPa) on Olympus Mons to over 1,155 Pa (1.155 kPa) in Hellas Planitia, with a mean pressure at the surface level of 600 Pa (0.60 kPa). The highest atmospheric density on Mars is equal to the density found 35 km above the Earth’s surface.

a better site to start a Balloon flight?

Banded Terrain in Hellas Planitia
https://mars.nasa.gov/resources/26375/b … -planitia/

Frost-covered chaos on Mars
https://www.esa.int/Science_Exploration … os_on_Mars

Last edited by Mars_B4_Moon (2023-12-24 11:43:21)

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#31 2023-12-24 10:50:37

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,460
Website

Re: Inter-settlement transportation on Mars

Human gee resistance depends upon your orientation.  you can take a lot laying down and properly supported,  not a hard flat floor,  up to about 40-45 gees,  where you literally start to come apart (a water balloon is only so strong,  and your cells are all effectively water balloons). The Apollo astronauts returning from the moon hit 10-11 gees for several seconds (around 10-20),  while lying down and well supported. 

Seated upright,  you can easily take 5-6 gees for a second or two.  People do it all the time on roller coasters with loop-the-loops.  But you tend to pass out at around 10 seconds exposure.  You can get past a few seconds at 5-6 gees with a gee suit that squeezes your legs and lower body.  For a single handful of seconds,  this even works at 9 gees. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#32 2024-04-20 13:10:28

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 9,267

Re: Inter-settlement transportation on Mars

the Skytram to go up and down mountain slopes and cliff to cross a Mars Valley, Rifts and Canyon?

Singapore Cable Car Launches World's First Skyorb Cabins
https://sg.finance.yahoo.com/news/singa … 00263.html

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