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#526 2020-11-08 20:26:03

tahanson43206
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Registered: 2018-04-27
Posts: 16,746

Re: Large scale colonization ship

For RobertDyck .... thanks for your recent additions to the topic ... I'll work on presentation starting tomorrow.

(th)

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#527 2020-11-11 15:17:57

RobertDyck
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From: Winnipeg, Canada
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Posts: 7,781
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Re: Large scale colonization ship

There's a YouTube video of the Enterprise D main shuttle bay. It's huge. A walking tour, very well done. Made me think I could do that for our Large Ship. The video was made with the Unreal game engine. Looking at that. Will have to upgrade my computer.

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#528 2020-11-14 09:34:25

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
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Re: Large scale colonization ship

As I understand this notion,  this is a large ship with artificial gravity and radiation protection.  The artificial gravity solves a host of logistical problems for ease of life support.

You can use nearly-ordinary toilets in the living spaces.  The only change is no water in them during periods of zero-gee operation,  or else a means of confining the water in them.  During those periods of zero gee operation,  you do need enough zero-gee toilets to handle the people on board as a temporary measure.

Assuming the atmosphere is synthetic air at something approximating a highland Earthly pressure,  you can use conventional cooking and food preservation.  Electric stovetops,  ordinary pots and pans,  the same kinds of foods we store in refrigerators and pantries here on Earth.  Astronaut rations heated in microwaves would only be a temporary expediency during periods of zero-gee operation.  Most conventional foods can be stored long term in freezers.  The exception would be fresh garden vegetables,  for which you need some sort of on-board garden space.

Now,  all that being said,  here's something few folks think about.  Your valuable cargo is more than the people on board,  and the equipment in the ship's cargo bay.  It is also the contents of your wastewater storage tanks!  No,  you DO NOT WANT to dump this stuff overboard while in transit! 

That sewage,  treated adequately,  is the feedstock for creating fertile soil out of the regolith at your destination,  be that the moon,  Mars,  or wherever.  That is the organic matter that makes rock dust into real soil.  It is also wet,  which is where you can get some of your agricultural water supply,  if you treat this stuff correctly. 

Just be careful how you apply it.  Spray irrigation with wastewater is the real source of many E-coli outbreaks in the Earthly fresh vegetable industry;  they should be doing flood or drip irrigation,  so as not to contaminate the leaves above ground. 

Those same sewage/wastewater tanks,  if disposed correctly about your design,  can also be part of your ship's radiation-shielding design.  As can the propellant tanks.

Just some food for thought.

GW

Last edited by GW Johnson (2020-11-14 09:39:10)


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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#529 2020-11-14 09:47:02

tahanson43206
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Registered: 2018-04-27
Posts: 16,746

Re: Large scale colonization ship

For GW Johnson re #528

RobertDyck will surely be coming along shortly to reply.

This is just a quick note about zero-G operation.   As I understand RobertDyck's vision, there will be NO Zero-G operation.

In earlier posts in this topic, RobertDyck has made clear he expects the ship to rotate at 1 revolution every 20 seconds from the time it is built and set in motion, until it is retired from service many decades later.

This specification for the design of the ship introduces interesting challenges for the engineers who must accept the specification and attempt to design a propulsion and guidance system that would permit such a concept to survive in the real-Universe.

I am skeptical, but I am supportive of RobertDyck's initiative because I would like to see the concept work in practice.

Fortunately, the physics of the concept can be tested on Earth in computer models, and a scale model can be tested in LEO in the ISS or whatever commercial space stations may come along in time.

Here is ** another ** example of how the new member admission policy will (or could) help the forum ....

There is an opportunity for existing members to recruit persons with expertise in software modeling of physical systems such as the proposed ship, and with the computing hardware and software capable of answering the question if such a design is practical.

If a member knows a person with the expertise needed, just post a note to SpaceNut in Housekeeping.

I expect that a simple review process will follow, after which the member record can be created from the 16,000 spam ID's created so helpfully by Spam robots over 20 years.

(th)

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#530 2020-11-14 10:11:24

GW Johnson
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From: McGregor, Texas USA
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Re: Large scale colonization ship

Question:  what if the ship gets damaged?  Do you not want to stop the spin during repairs,  then re-spin?  Passengers will not be aboard,  but a repair crew will be.  This may take significant time. 

Question:  what about during construction,  before you spin the thing up.  The construction crew will be aboard,  living inside those spaces already built and pressurized. 

Question:  as I understand it,  RobertDyck wants to use aerobraking to reduce transit propellant required.  What if that proves incompatible with a spinning ship?  If that proves to be the case,  then you must de-spin before aerobraking.  And how long/how many passes will that take?  Days?  Weeks?  Months?

These things affect design practicality.  I'm no expert in all these areas,  but I do know intimately well how things will interact in unexpected ways,  and just how complicated life can actually get,  when you are doing design of some product or system. It is NEVER simple.

GW

Last edited by GW Johnson (2020-11-14 10:13:25)


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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#531 2020-11-14 10:19:37

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Large scale colonization ship

SpaceNut wrote:

The mars homestead waste recovery addresses the sewage use for growing in poor quality soils. see crop topics

http://www.marshome.org/

Building soil

4Frontiers

MarsHome project - seems to be well underway

Wastewater Treatment

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#532 2020-11-14 12:16:44

tahanson43206
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Registered: 2018-04-27
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Re: Large scale colonization ship

For GW Johnson re interesting questions ....

The definitive answer awaits the return of RobertDyck ....

GW Johnson wrote:

Question:  what if the ship gets damaged?  Do you not want to stop the spin during repairs,  then re-spin?  Passengers will not be aboard,  but a repair crew will be.  This may take significant time.

Question:  what about during construction,  before you spin the thing up.  The construction crew will be aboard,  living inside those spaces already built and pressurized.

Good point ...
However, I am hoping for two (minor) modifications of RobertDyck's vision as the possibility of funding approaches:

First, components that can be assembled on Earth and lifted by a Starship could be.  It might turn out that doing that would make sense.
Second, assembly on orbit no longer need involve humans.  By the time this vehicle is ready for assembly, teleoperation will be well enough advanced so that no humans need be present at all.

Question:  as I understand it,  RobertDyck wants to use aerobraking to reduce transit propellant required.  What if that proves incompatible with a spinning ship?  If that proves to be the case,  then you must de-spin before aerobraking.  And how long/how many passes will that take?  Days?  Weeks?  Months?

Lawdy, I hope ** that ** idea has faded quietly into the sunset.  The impression I'm getting is that RobertDyck is willing to accept the cost of taking some propellant along to "dock" with Mars will be worth the expense, as compared to the expense of equipping a vehicle with 1060 souls on board to survive the high risk of trying to aerobrake.

However, the larger issue at hand is quite an interesting one ... assuming (for the moment) that RobertDyck's vision of an ever-rotating vessel can be proven to survive computer modeling, the methods of propelling and steering the vessel will confront the engineers who tackle that aspect of the design.

These things affect design practicality.  I'm no expert in all these areas,  but I do know intimately well how things will interact in unexpected ways,  and just how complicated life can actually get,  when you are doing design of some product or system. It is NEVER simple.

Hopefully the folks who are enlisted to help RobertDyck to move forward with this project will be able and willing to deal with the complexity of a ship of this magnitude.  Ultimately, I would expect a cast of thousands to handle the myriad details that will show up on the task lists.

GW

(th)

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#533 2020-11-14 12:22:34

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

GW Johnson, greetings! I really appreciate having a real engineer onboard.

Yes, the plan is for rotation from construction until decommission. The ship hull will be built in zero-G; expect a lot of use of drones. Once the pressure hull is completed, tested, and pressurized, it will be spun-up. Interior cabin walls and fitting can be installed while artificial gravity is in place. Since primary life support is in a wall of each cabin, that means life support won't be operating during construction work. A module installed in the "roof", one per pressure compartment, will include air conditioning compressor, battery to store power from solar panels, final water filtration to convert grey water to potable. That roof module will also include pressurized oxygen and pressurized diluent gas to deal with leaks. Diluent gas is air without oxygen. That would be in place and operational before construction crew start installing interiors. Each pressure compartment would be connected to the next to share electric power, oxygen, diluent gas, and water. The water tank will be built into the sun-facing wall for radiation shielding. The entire habitation ring will be shielded, but only the one main deck. Life support built into the cabin washroom/restroom/lavatory will filter urine the same way ISS does now. Water will go to a water processing module that will further filter, producing grey water. Concentrated urine will be piped to an onboard greenhouse for processing, so it can be used as fertilizer. Excess urine will be piped up the wheel spokes to the zero-G hub. As you recommended, sewage will be stored in separate containers on the outside of the zero-G hub. That sewage can be taken down to the surface of Mars as organic fertilizer.

The toilet will not have water in the bottom like modern flush toilets; it'll be dry until someone uses it. The toilet will have a built-in "washlet", which is a bidet to wash the user's backside. When the toilet is "flushed" it will seal shut, and vacuum desiccate the feces. This will recover wash water as well as moisture in feces. The feces will be desiccated bone dry, then put through a garberater in the toilet to turn it to powder. The powder will be transported through pipes with compressed air and an augur in the pipe to spokes where it will be piped up to the zero-G hub. That powdered feces will also be stored in sewage containers for delivery to Mars.

During construction, before cabin and public washrooms are not yet connected, construction crew will require a "port-a-potty". That can be designed to operate in zero-G.

Construction crew could wear an oxygen mask until life support is operational. However, I expect construction crew will find an easier solution. They could close off the section they're currently working in with plastic sheet, and operate an oxygen generator in there. Just so they can remove the oxygen mask. My current job has occasionally required me to install computer equipment in a construction site. At one site there were construction workers installing carpet, counters, etc. It was a single story building with the ceiling up, but safety rules by the construction firm "PCL" required everyone to wear a hardhat and safety goggles. None of the construction workers wore a hardhat, but they had one beside them just in case. When the safety inspector arrived, they all put on their hardhat and goggles. I was a computer tech, wasn't told this was a construction site, I work after construction is finished. The safety inspector ordered me to get a hardhat and goggles. The other computer techs laughed at me that I was caught; they didn't wear a hardhat but got used to giving excuses to the inspector. The temp service allowed me to expense the hardhat and goggles. A store selling them was across the parking lot in the same mall, my time to buy them was considered billable. But as soon as I got back, the safety inspector was gone so all of the construction workers took off their hardhat and goggles. I used my goggles when drilling into the server rack to install a door sensor, but didn't wear them when I wasn't drilling. When installing equipment into a rack or plugging patch cables, why would I? After that experience, I expect construction workers will find a way to avoid wearing an oxygen mask. Just plan for it.

I expect damage to be repaired while spinning. Yes, the ship can be de-spun for extreme repairs, but shouldn't be required for expected issues. Since cabin toilets won't have water when not being used, that means we can remotely shut off the water to passenger cabins. That would prevent zero-G problems. To address your concern, does that mean public toilets have to be capable of operation in zero-G? In case de-spin is required with passengers onboard?

Onboard greenhouse will be aquaponics. That's a combination of hydroponics and aquaculture. The aquaculture tanks will be sealed so that if the ship is de-spun, water won't drift out. Plants in hydroponics will be tied to support frames, plants can grow through a thin sheet of styrofoam to contain water around their roots, but loss of artificial gravity would create a mess. I have argued for soil agriculture on Mars; why extract nutrients from Mars dirt just to create hydroponic solution? Instead let plants extract nutrients themselves. Yes, Mars dirt will have to be treated to make it suitable soil for agriculture. But the ship won't have access to Mars dirt, you have to carry everything with you. So the ship will use hydroponics and aquaponics. I expect to grow salad and vegetables onboard, and aquaponics will provide fresh fish; other food will be stored.

In one post I calculated aerocapture. In a single pass that passes through 1/4 of the circumference of Mars, and deceleration of a fraction of a G, the ship would enter an orbit with a 3 to 4 day period after just one aerocapture pass. I'll find that post and add a link to it.

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#534 2020-11-14 12:26:40

SpaceNut
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From: New Hampshire
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Re: Large scale colonization ship

https://www.space.com/spacex-starship-i … -musk.html

https://www.inverse.com/article/59721-s … d-for-mars

https://www.spacex.com/media/starship_u … ide_v1.pdf

The payload bay that opens much like shuttles did will have a cone shape at maximum for the parts to build the station with and possible cylinder modules of a much smaller diameter. This means that building will be in many smaller pieces that will need to have a shell assembled around once in place.

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#535 2020-11-14 12:31:56

RobertDyck
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Re: Large scale colonization ship

Post #387

NASA Ames Research Center Trajectory Browser

 	 	 	Orbit						   Injection	     Injection 	Post-	Total
SPK ID 	Name	 Size 	cond.	Earth		Destination	Duration 	C3 	Abs       ΔV 	Inject.	 ΔV    Route
 	 		code 	Departure 	Arrival 		    (km2/s2)	DLA	(km/s) ΔV(km/s) (km/s)

499	Mars	6779 km	0	Nov-02-2024	Apr-27-2025	176 days	25.9	25°	4.34	2.44	6.78	EM
499	Mars	6779 km	0	Nov-18-2024	Apr-27-2025	160 days	46.1	25°	5.15	2.52	7.67	EM
499	Mars	6779 km	0	Nov-18-2024	Apr-11-2025	144 days	48.1	26°	5.23	3.49	8.72	EM

Post #389 click here

ΔV is not dependand on mass. Acceleration (deceleration) during aerocapture is not either. Acceleration is dependant on ΔV and time to achieve it. The greater the change of velocity, the greater the acceleration required. The more time acceleration is applied, the lower the acceleration. Mass simply changes thrust required to achieve that acceleration.

Reading the user guide for the NASA orbital calculator... "Post-Injection ΔV" is that required to achieve orbit with periapsis just barely out of the atmosphere, and C3=0. That means minimum reduction of energy to just enter orbit. Pushing the calculator to the extreme, difference between highest periapsis velocity I can get to orbital period of 3 days changes periapsis velocity from 4.999 to 4.896 km/s. That's a change of just 0.103 km/s. So "Post-Injection ΔV" for Nov-02-2024 is 2.44 km/s. So add 0.103 to get 2.543 km/s. For a rough calculation, assume aerocapture occurs over 1/4 the circumference of Mars at the altitude of periapsis, so 5,383km. Velocity will initially be speed of periapsis plus ΔV, so 4.896 + 2.543 = 7.439 km/s. Using this calculator result is 2.91361 m/s² over 872.801 seconds (14 minutes, 32.801 seconds). Earth's surface gravity is 9.80665 m/s² so that's 0.2971 G.

The ship will be rotating with Mars gravity, so this will feel quite dramatic. Direction of "down" will change to 38° off vertical for 14½ minutes. Total magnitude of gravity (centrifugal plus deceleration) will be 0.48 G.

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#536 2020-11-14 15:25:43

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Large scale colonization ship

RobertDyck:

My attention has been focused elsewhere,  but I am trying to get my head on straight about what you are attempting.  Forgive me if I ask stupid questions.  I don't know a lot about your design yet. 

Q: "To address your concern, does that mean public toilets have to be capable of operation in zero-G? In case de-spin is required with passengers onboard?" --

-- A: no,  but I would make some of them zero-gee capable.  Just enough of them to serve the whole population,  in case some unimagined emergency forces de-spin with passengers aboard.  It's sort of like having enough lifeboats in case the ship ever sinks. 

Another key to sizing that:  how many souls might be aboard if this ship ever has to rescue people from another ship?  That absolute max number of souls aboard is your planning number for these unimaginable emergencies.  Which Murphy's Law says will happen.  Someday. 

I am surprised and pleased to see the aerobrake capture done in one gentle pass,  and only several days to enter orbit.  That's quite good,  and way beyond what I could estimate with a pencil,  a piece of paper,  and a slide rule or calculator.  Which is the kind of thing I actually can do.  It was how we did most things when I first entered the workforce.  A long time ago (in a galaxy far away).....

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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#537 2020-11-14 17:00:50

RobertDyck
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Re: Large scale colonization ship

Um, well. Current working design is normal complement 1,000 passengers, 66 crew. If every "standard" cabin is configured as economy class (third class), and a passenger in every bunk, and if luxury suites are subdivided into the smallest size (club cabin) with maximum number of passengers there, then 1,552 passengers and 66 crew. Could I squeeze in just a few more passenger cabins?

Problem with lifeboats is interplanetary orbits. If all passengers evacuate to lifeboats while enroute to Mars, they'll continue a trajectory to Mars. A 6 month transit is a free return, so thrust small enough for a lifeboat to swing around Mars, head back to Earth. Life boats wouldn't have aerocapture capability. That means roughly 2 years before they return to Earth. Earth and Mars align every 26 months, so a rescue ship would take that long. If lifeboats have 3 days life support, they're dead before rescue arrives. If they have 2 weeks life support, a system like Apollo, then they're still dead. So capsules that can enter planetary atmosphere and land, either on Mars or Earth? That could still be months, up to 6 months, and the escape pods (lifeboats) would have to be Apollo style capsules. That's big and heavy. Modern aircraft carriers use inflatable lifeboats to reduce size and weight. NASA developed an inflatable rescue sphere, but it's just a sphere made of spacesuit material with no PLSS. Sized for one person. How long can you hold your breath?

Instead I have separated the ship into pressure compartments. Floor plan looks like this...
kFu65wI.jpg?1
The bulkhead between forward and aft inside cabins is a pressure wall, so each pressure compartment is separated into two sub-compartments. If one sub-compartment is struck by a fist-size meteoroid and decompresses, then pressure tight doors on each end of the corridor of this one sub-compartment will close. The sun-facing wall is a water tank, floor-to-ceiling. That acts as radiation shield, and water reservoir. Somewhere on the roof is one equipment box for the pressure compartment with compressors for air conditioning, electric storage batteries, reserve air tanks, and filtration to process grey water into potable. So both sub-compartments share this life support equipment. But each pressure compartment is self contained so can operate on it's own. It has pipes and cables connecting to neighbouring pressure compartments, but distributed equipment means if something catastrophic happens then only that one compartment is disabled, the rest of the ship is not. Yes, that means where pipes connect to neighbouring compartments, there's a solenoid valve on both sides of the pressure bulkhead. Solid state relay can cut off power to the cables that share power to the next compartment, in case one compartment gets damaged and produces a dead-short to the power cables.

Again, for life boats, if you designed something like a Dragon capsule but able to squeeze in 48 people, then you would need one for each sub-compartments. Each lifeboat capsule would have to be able to enter Earth's atmosphere from interplanetary velocity. And would require up to 6 months of life support, so that means recycling life support. Plus food. And the capsules would have to be able to enter Mars atmosphere, so that means in additional to a PICA heat shield for Earth it would require a deployable heat shield (ADEPT or HIAD) for Mars. A parachute would have to work in Earth's atmosphere, and Mars. It would have to be able to splash down, and rockets to land on Mars. This isn't practical. A commercial airline on Earth doesn't have lifeboats, so instead my focus is to create backups and compartments within the ship itself to act as lifeboats. After all, this isn't ocean, it can't sink; the danger in space is vacuum and life support. So back that up.

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#538 2020-11-14 19:11:31

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Large scale colonization ship

I did not mean you need escape pods (lifeboats) for your spaceship design.  I meant you plan on excess population for all sorts of things,  sort of analogous to how they now decide on the number of lifeboats installed on ships at sea. 

The scenario is rendezvousing with another craft in the same basic trajectory that has become disabled.  You take their people aboard.  You have to have the life support,  food,  water,  air,  and potty capacity to handle them,  even if you are forced to despin for some reason. THAT is what I meant.

GW

Last edited by GW Johnson (2020-11-14 19:12:46)


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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#539 2020-11-19 06:47:25

RobertDyck
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From: Winnipeg, Canada
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Posts: 7,781
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Re: Large scale colonization ship

Competition... sort of. They don't want a spacecraft to Mars, they want a space hotel. This changes a lot. For one, lifeboats are possible because they can simply return to Earth. And short duration stay (weeks) is possible, while a Mars ship is limited by orbits of the planets about the Sun. A Mars ship can be used as a space hotel briefly while waiting for alignment for the next trip, but these guys want a dedicated orbital hotel.

Space hotel with artificial gravity will be in orbit by 2025

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#540 2020-11-19 08:07:48

RobertDyck
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Re: Large scale colonization ship

Well! On Facebook, one individual claiming to be a co-founder claims that article is already out of date. I saw the article on Facebook this morning, that's quick. An admin on the Mars Society group on Facebook already deleted it. What does that say about the project?

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#541 2020-11-19 12:34:29

tahanson43206
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Registered: 2018-04-27
Posts: 16,746

Re: Large scale colonization ship

For RobertDyck re topic ...

https://forms.monday.com/forms/9f862eef … 9f574bdabf

This online Project Management service appears to be offering a free service for qualifying Non-Profit organizations.  I'm sure the Mars Society would quality, but I also assume an officer (such as James Burk) would have to apply for the certification.

Please take a look at this site, to see if it might be worth bothering Mr. Burk with the request.

***
We need to find a way to up our game for recruiting people to help with the project.  Now that SpaceNut has closed off open registration, the possibility exists to improve the status of the NewMars forum, so that at some point it will qualify for consideration by professional people.  In the mean time, it ** should ** be acceptable to people who are retired from full time employment, but who are interested in advancing worthwhile projects such as yours.

(th)

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#542 2020-11-21 11:24:04

tahanson43206
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Registered: 2018-04-27
Posts: 16,746

Re: Large scale colonization ship

For RobertDyck re topic ...

The article at the link below includes a reference to a potential resource:


https://currently.att.yahoo.com/lifesty … 38505.html

10 things you didn't know about building cruise ships
Gary Buchanan
The TelegraphFri, November 20, 2020, 5:36 AM EST

Creating a cruise ship is a complex procedure that brings together a wide range of cutting-edge technologies in a finite space. To throw some light on the process, Telegraph Travel spoke to a man who knows a thing or two about designing ships. Per Lindqvist is the US business director for Tillberg Design of Sweden Inc, a renowned company who has created the design concepts for illustrious ships, including Regent Seven Seas Splendor, Crystal Endeavor and Norwegian Encore.

(th)

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#543 2020-11-22 17:10:00

SpaceNut
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From: New Hampshire
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Posts: 28,747

Re: Large scale colonization ship

I think this was covered if not in this topic it could have been another but is there A Doctor onboard or a qualified surgeon paper from Mars Society.

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#544 2020-11-22 18:08:17

RobertDyck
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Re: Large scale colonization ship

SpaceNut: yes. My design includes an infirmary, with one medical doctor and one nurse. From post #307

RobertDyck wrote:

Here's an actual reference, what it's like to be a doctor on a cruise ship.
What to do if you want to be a cruise ship doctor

You will usually see 10 to 20 patients per day, mostly with minor problems. The top five most common issues seen (based on my informal poll of doctors I’ve talked to on ships) are; MI, stroke, fractures, lacerations and GI issues (not infectious). These are pretty typical problems faced by the elderly population that frequent these ships. I, at age 55, am younger than almost every paying passenger on the ship. There are some cruises though that cater to a younger crowd, like Disney for example. On those cruises, some pediatric problems might be seen.

Ships have a mini hospital on board. They are required to have at least one hospital bed per 1,000 passengers. Most ships have an ICU bed and a few regular beds. They keep the usual assortment of medications, simple X-ray services, minor surgical equipment, lumbar puncture tray, EKG machine and the basic equipment found in a medical ICU, including the ability to intubate. When a ship is at sea, the ship needs to carry everything needed to get the patient through their problem until the ship arrives at the next port. At that time, the patient is evaluated to determine if the patient’s problem can be treated well on the ship, or if the patient needs to be off-loaded to a local hospital.

Obviously a Mars ship cannot offload anyone until it arrives on Mars. Typical cruise ship carries 3,000 passengers, largest ones carry 6,000. Passengers, not crew. This Mars ship will carry 1,000 to 1,200 passengers.

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#545 2020-11-22 20:36:35

SpaceNut
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From: New Hampshire
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Re: Large scale colonization ship

The gyro ship topic and this one this paper relates to... Solar powered Deep space wheel ship for long term manned missions

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#546 2020-11-22 21:00:46

tahanson43206
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Re: Large scale colonization ship

For SpaceNut re #545

Thanks for showing the Chipman paper .... I was not aware of the limitation of VASIMIR engines (at the time and perhaps still) of being able to operate only with pulses.  The author's solution seems reasonable.

The coincidence I note is the concept posted by RobertDyck to pulse thrusters to navigate his Large Ship design.

(th)

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#547 2020-11-23 03:31:45

Terraformer
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From: Ceres
Registered: 2007-08-27
Posts: 3,800
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Re: Large scale colonization ship

Re. medical staff, how many of the passengers will be qualified? If we're talking about 1200 colonists, maybe 4 of them will be doctors themselves (based on a ratio of 1 doctor per 300, which is apparently typical for developed countries), and 8 of them nurses. There's no reason to have them sitting idle in their cabins. Not to mention people who could train as physicians assistants and associate nurses.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#548 2020-11-23 07:29:34

tahanson43206
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Re: Large scale colonization ship

For Terraformer re #547

There is the potential of drift here, if we depart too much from the parameters RobertDyck has provided: 1000 passengers and 60 crew now up to 66.

Your point was (as I understand it) that there could be doctors and nurses (medically trained personnel) in the passenger list, and I agree that if they are present they could be enlisted to help care for the crew.  However, at the point in time where a ship of the size of RobertDyck's vision is operating routinely, it may be that the kinds of people recruited to travel to Mars might not reach the skills levels needed by Mars in particular areas by default.

It may be necessary to add incentives to recruit particular combinations of education and skill.

It would seem appropriate (to me at least) to recruit medical personnel for every flight, but other priorities on Mars may be greater at a given time.

In any case, for psychological health, it is my impression that every person should have assignments to complete during the voyage, and if an individual is qualified to provide medical care, then that would seem to be an appropriate focus. 

(th)

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#549 2020-11-23 13:46:34

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

We could offer a discount to passengers who chose to work as crew. I would suggest 1 doctor and 1 nurse as full-time dedicated crew members. Passengers could register their skills for assistance in emergency situations, such as medical doctors, nurses, orderlies, paramedics, etc. We could assign the one last crew cabin for passengers willing to work as crew. While crew members may be asked to work long shifts and have authority, passengers working as crew would work shorter shifts and limited or no authority. Examples:

  • housekeeping - equivalent to maid in a hotel. Title on an ocean-going ship is steward, on this spaceship they would also be steward. During emergency situations they would have all the authority of a airline stewardess. Note: female word for steward is stewardess, but we're going genderless in the 21st century. Airline stewardesses were originally registered nurses, there to help rich passengers who might suffer motion sickness from flying. Modern airline stewardess is not a nurse, but does have authority to direct passengers in an emergency, and can kick you off the aircraft if you become unruly. A passenger with housekeeping experience could work as a housekeeping steward, but only asked to work 8 hours per day, 5 days per week. And a passenger working as crew would not have "stewardess" authority.

  • laundry - I'm told by a young woman who worked at a hospital that laundry is separate from housekeeping. Still a subdivision of steward.

  • table waiter - Again this is a subdivision of steward. Again, permanent crew would have authority of an airline stewardess but a passenger working for a discount would not. Only the "fine dining" room would have table waiters. Other dining rooms would be buffet, so they would need staff to "bus" tables. "Busboy" or "busgirl"? Still a subdivision of steward.

  • lecturer - this could be an astronomer, giving a tour of the sky from one of the observation decks. Or a scientist with knowledge of Mars: geologist, astrobiologist, etc. Someone who can give an interesting presentation about what passengers are going to find when they get to Mars. Science outreach.

  • security - these guys require authority to do their job. But security shouldn't be needed 24/7. On a passenger ship with 1,000 to 1,200 passengers, they shouldn't be busy most of the time. Needed only when something happens. Perhaps watching video feed from security cameras when not responding to an incident.

  • engineering - electrician, plumber, computer/smartphone/networking technician, tradesmen capable of doing ship repairs/maintenance while underway

  • warehouse worker - on a ship the title is "sailor". Duties include janitorial, cargo rigging and handling. This includes carrying boxes of food from zero-G storage in the cargo hold down to kitchens. Janitor duties overlap with engineering - a janitor is expected to do simple repairs to the heating system. And overlaps with housekeeping - janitor is expected to clean public spaces like corridors while housekeeping cleans passenger cabins. Passengers are expected to clean their own cabins, but could get maid service one per week or something like that. If a toilet in a school or office building clogs, the janitor is required to fix/unclog/clean. In a hotel, the maid does that. On a ship, if a security incident breaks out that's too much for security, sailors are expected to provide additional muscle. So "sailor" is jack-of-all-trades, master of none?

  • exercise consultant - in the gym, reporting to Chief Steward

  • farmer - working in the greenhouses. Especially hydroponics, aquaculture, aquaponics. Reporting to Petty Officer, not Chief Steward?

When I tried to draw floor plans for crew cabins, I realized it's just a standard pressure compartment with the usual number of standard cabins. With one extra cabin left over. That extra cabin could be configured as economy class, same as enlisted crew, which would provide 6 more bunks. That increased crew from 60 to 66. Could the extra 6 crew be passengers working for a discounted ticket?

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#550 2020-11-23 15:23:30

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
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Re: Large scale colonization ship

Make one of those a dietician and nutritionist for that medical staff and its a go to ensure that all eat right and do not have any issues from what they are eating due to the trips strenuous conditions that are not trained for them.

There is no reason why some one that goes on the journey can not work a 4 hr shift to the benefit of all....

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