Ship Design Philosophy

Discuss the Traveller RPG and its many settings
Condottiere
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Re: Ship Design Philosophy

Postby Condottiere » Sat Dec 15, 2018 11:32 am

Spaceships: Engineering and Upward Bound Power Satellites

Beaming energy down from satellites in orbit to replace the production of electricity on Earth may solve many of our problems, and avoid a potential economic or ecological crisis such as energy bottlenecks or global warming. Today we will explore how wireless microwave transmission of energy down to rectennas may not only be possible, but could be massively profitable in the near future and spur our exploration and colonization of space.

https://www.youtube.com/watch?v=eBCbdThIJNE


Even if you think on the small scale, you can power drones that follow your ship like pilot fish.
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Re: Ship Design Philosophy

Postby Condottiere » Sun Dec 16, 2018 12:18 am

Spaceships: Engineering, and Little Rockets, Man!

Well, firmpointed big rocket pods.

Anyway, the only advantages that rocket motors have is that move faster up the tech tree than manoeuvre drives, and they are five times cheaper.

I think they're simple to maintain, repair and manufacture in comparison to the alternative.

However, they are gas guzzlers, and it's unclear how they stand in regard to inertial compensation, meaning it's pretty much guesswork if you could maintain acceleration beyond three gees without killing the crew.

Combine that short duration with the normal rotation of twelve hour pilot rotations, you could install them in combat craft that wouldn't be expected to remain long on the line, or far from a mothership.

I think most commercial concerns will upgrade to manoeuvre drives as soon as they can afford it.

I think it will eventually come down to gravitated hulls equals inertial compensation as well, or if it requires a manoeuvre drive to create an inertial compensation field.
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Re: Ship Design Philosophy

Postby Condottiere » Sun Dec 16, 2018 4:38 pm

Spaceships: Armaments, Sandcasters and High Explosives

Image

A general-purpose bomb is an air-dropped bomb intended as a compromise between blast damage, penetration, and fragmentation in explosive effect. They are designed to be effective against enemy troops, vehicles, and buildings.

...

General-purpose (GP) bombs use a thick-walled metal casing with explosive filler (typically TNT, Composition B, or Tritonal in NATO or United States service) composing about 30% to 40% of the bomb's total weight. The British term for a bomb of this type is "medium case" or "medium capacity" (MC). The GP bomb is a common weapon of fighter bomber and attack aircraft because it is useful for a variety of tactical applications and relatively cheap.

General-purpose bombs are often identified by their weight (e.g., 500 lb, 227 kg). In many cases this is strictly a nominal weight (the counterpart to the caliber of a firearm), and the actual weight of each individual weapon may vary depending on its retardation, fusing, carriage, and guidance systems. For example, the actual weight of a U.S. M117 bomb, nominally 750 lb (340 kg), is typically around 820 lb (372 kg).

Most modern air-dropped GP bombs are designed to minimize drag for external carriage on aircraft lacking bomb bays.

In low-altitude attacks, there is a danger of the attacking aircraft being caught in the blast of its own weapons. To address this problem, GP bombs are often fitted with retarders, parachutes or pop-out fins that slow the bomb's descent to allow the aircraft time to escape the detonation.

GP bombs can be fitted with a variety of fuzes and fins for different uses. One notable example is the "daisy cutter" fuze used in Vietnam War era American weapons, an extended probe designed to ensure that the bomb would detonate on contact (even with foliage) rather than burying itself in earth or mud, which would reduce its effectiveness. (This was not the first instance of such devices. As early as World War II, the Luftwaffe was using extended-nose fuzes on bombs dropped by Stuka dive-bombers and other aircraft for exactly the same reason. A blast several feet above the ground is many times more effective and has a far greater radius than one that is delayed until the bomb is below the surface.)

GP bombs are commonly used as the warheads for more sophisticated precision-guided munitions. Using various types of seeker and electrically controlled fins turns a basic 'iron' bomb into a laser-guided bomb (like the U.S. Paveway series), an electro-optical guided bomb, or, more recently, GPS-guided weapon (like the U.S. JDAM). The combination is cheaper than a true guided missile (and can be more easily upgraded or replaced in service), but is substantially more accurate than an unguided bomb.

...

A Mk. 82 GP bomb loaded on an F/A-18 Hornet, showing nose fuze and textured thermal insulation
During the Korean War and Vietnam War the U.S. used older designs like the M117 and M118, which had an explosive content about 65% higher than most contemporary weapons. Although some of these weapons remain in the U.S. arsenal, they are little used and the M117 is primarily carried only by the B-52 Stratofortress.

The primary U.S. GP bombs are the Mark 80 series. This class of weapons uses a shape known as Aero 1A, designed by Ed Heinemann of Douglas Aircraft as the result of studies in 1946. It has a length-to-diameter ratio of about 8:1, and results in minimal drag for the carrier aircraft. The Mark 80 series was not used in combat until the Vietnam War, but has since replaced most earlier GP weapons.

...

Since the Vietnam War, United States Navy and United States Marine Corps GP bombs are distinguished by a thick ablative fire-retardant coating, which is designed to delay any potential accidental explosion in the event of a shipboard fire. Land-based air forces typically do not use such coatings, largely because they add some 30 lb (14 kg) to the weight of the complete weapon.[citation needed] Fire is less a danger in a land-based facility, where the personnel can be evacuated with relative ease, and the building be the only loss. At sea, the crew and munitions share a facility (the ship), and thus are in much more danger of fire reaching munitions (which tend to be more closely packed, due to space limitations). Also, losing a munitions storage building on land is far cheaper than sacrificing an entire naval vessel, even if one could easily evacuate the crew.

All Mk80 bombs have both nose and tail fuze wells and can accept a variety of fuzes. Various nose and tail kits can be fitted to adapt the weapon for a variety of roles.

...

The Mark 84 has a nominal weight of 2,000 lb (907.2 kg), but its actual weight varies depending on its fin, fuze options, and retardation configuration, from 1,972 to 2,083 lb (894.5 to 944.8 kg). It is a streamlined steel casing filled with 945 lb (428.6 kg) of Tritonal high explosive.[1]

The Mark 84 is capable of forming a crater 50 feet (15.2 m) wide and 36 ft (11.0 m) deep. It can penetrate up to 15 inches (381.0 mm) of metal or 11 ft (3.4 m) of concrete, depending on the height from which it is dropped, and causes lethal fragmentation to a radius of 400 yards (365.8 m).[3]

Many Mark 84s have been retrofitted with stabilizing and retarding devices to provide precision guidance capabilities. They serve as the warhead of a variety of precision-guided munitions, including the GBU-10/GBU-24/GBU-27 Paveway laser-guided bombs, GBU-15 electro-optical bomb, GBU-31 JDAM and Quickstrike sea mines.[4] The HGK is a Turkish guidance kit used to convert 2000-lb Mark 84 bombs into GPS/INS guided smart bombs.[5]

According to a test report conducted by the United States Navy's Weapon System Explosives Safety Review Board (WSESRB) established in the wake of the 1967 USS Forrestal fire, the cooking off time for a Mk 84 is approximately 8 minutes 40 seconds.



1. How much of that fits into 0.7 cubic metres?

2. Since there is no air resistance in space, you could drop rectangles.

3. Laser guided kits are optional.

Image
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Re: Ship Design Philosophy

Postby Condottiere » Mon Dec 17, 2018 8:36 am

Spaceships: Hulls, Stealth and Salt-infused graphene creates an infrared cloaking device

Infrared emissions that are controlled by salt infusion make good camouflage.

CHRIS LEE - 8/3/2018, 4:09 PM
That's not a Warhol. That's the material described here, showing fine control over whether it's hotter or colder than its surroundings.

I love light and the various manners in which we can control it. It's a good time for me, as we are truly in a golden age of light control. We can manipulate it to see details that would otherwise be invisible. We can guide it around objects so that they are invisible. Light has been made to stand still and dance on the pointy end of pins.

All this control of light is indirect, coming via our control of materials that the light interacts with. Now, researchers have crafted a material that adapts its properties so that its infrared appearance is either hotter or colder than the object it encloses. In other words, hot objects appear cold, or cold objects can appear hot—it's infrared camouflage.

It’s all about those electrons

So, do you make yourself some infrared camo gear? The basic procedure is to control the efficiency with a material that can emit infrared radiation. Take gold as an example. Gold is a nearly perfect metal: it has high conductivity and does not absorb infrared radiation very easily. That means it will reflect incoming radiation; this is why emergency blankets have a thin gold coating: the gold reflects your own infrared radiation back to you to keep you warm.

At the other end of the scale you have something like the black soot from a fire. Soot is not very reflective, so the background infrared radiation is not scattered by the soot. But, if it is placed on a heating plate, it will glow in the infrared. Gold, by contrast, doesn't tend to emit at these wavelengths.

The efficiency with which a material emits (or absorbs) light is described by its emissivity, which scales from zero to one. Gold is very close to zero, while a perfect emitter (like soot) is close to unity.

Emissivity is the knob that the researchers turn to control the infrared appearance of their material. To do this, they make use of the unusual properties of graphene. Graphene is a single layer of carbon atoms, all arranged in a hexagonal pattern. It's not quite a metal; it is more like a semiconductor like the silicon that the CPU powering the device you're reading this on is made from. The difference is that silicon only starts to conduct if you apply a measurable voltage to it, while graphene starts to conduct as soon as the voltage is non-zero (this is called a zero band gap semiconductor). This means that graphene always has electrons available to conduct—but not all that many. And, when you take into account defects in fabrication, the conductivity of some graphene layers can be quite poor.

But, like other semiconductors, the conductivity can be changed by adding impurities that contain additional electrons. For instance, adding a small amount of phosphorus to silicon gives it a higher conductivity, because phosphorus has spare electrons to give up.

A salty blanket

The researchers made a thick graphene layer (around 100 to 150 graphene sheets thick) that had very poor conductivity. As a result, the emissivity of the layer is quite high. Under that layer, they placed a thin coating of ionic fluid. The ionic fluid is, essentially, a liquid salt (not a salt dissolved in water). The liquid salt was sealed in place by a thin layer of transparent plastic and the whole lot was placed on a thin gold electrode.

Under ordinary conditions, the salt layer sits outside the graphene layer, which absorbs and radiates infrared light. However, if a voltage is applied between the graphene layer and the gold layer, then the ions in the liquid move into the graphene, giving it a higher conductivity. As a result, it stops absorbing and radiating infrared radiation and becomes an infrared reflector. Even better, the transition from absorber to reflector is controllable. Different voltages result in different conductivities, so the emissivity of the graphene layer varies continuously from its maximum to its minimum value (0.8 to 0.35).

What does that mean? Well, imagine placing this over a hot plate. If the emissivity is set to its minimum value, the hot plate will appear to be the same temperature as its surroundings: it is hidden. But you can also go the other way: if the emissivity is increased, then the hot plate will appear to be hotter than it otherwise would.

At first this appears counterintuitive: if the layer is glowing hotter than the thing it is covering, surely the material is actively cooling the hot plate. I would say that, on the face of it, this has to be true. But in practice, it depends on a number of factors: the temperature of the object depends on the efficiency of its infrared radiation emission but also on its conduction to the surroundings and convection (the mass motion of warm fluid, like air, carrying heat away). The covering could simply change the balance between these different heat transfer mechanisms rather than actually cool the covered object.

Seeing is believing

The researchers show lots of pictures and movies of their material camouflaging hot objects. They show that the material is flexible, so it could be worn. And, equally important, it is vacuum compatible.

It may come as a surprise, but keeping things cool or warm in vacuum chambers and in space is a proper challenge. Under ordinary circumstances, convection carries the majority of heat away from a warm object—this is why radiators are so good at keeping houses warm. In a vacuum, there is nothing to carry the heat. So, in the end, the only way to control temperature is through changing how efficiently heat is radiated from surfaces. And, now we have a material that can do this. I think that is probably the more important application.

Of course, we don’t know how physically robust the material is or how many emissivity transitions it can do before it stops working. But, assuming these pan out and that the ionic liquid is not too expensive or toxic, then I can imagine this turning up in specialist applications pretty quickly.

https://arstechnica.com/science/2018/08 ... ng-device/


Insaltation.
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Re: Ship Design Philosophy

Postby locarno24 » Mon Dec 17, 2018 9:11 am

Condottiere wrote:
Sun Dec 16, 2018 4:38 pm
Spaceships: Armaments, Sandcasters and High Explosives

1. How much of that fits into 0.7 cubic metres?

2. Since there is no air resistance in space, you could drop rectangles.

3. Laser guided kits are optional.

The Mk82 - the 500lb version, and pretty much the lightest - is a couple of metres long by just under a foot across as an 'all-up' round (with a standard nose and tail fitted)

You could fit 5 of those plus some change (which would get used for brackets and grips) in 0.7 m3


The tactical value is.....questionable:
~ Versus a mobile target capable of manoeuvring at several G, ballistic warheads won't achieve much outside pretty much point blank range
~ Might be useful for a stationary target - on the one hand a ballistic target is a bloody easy job for point defence, on the other a non-radiating ballistic object might stand a chance of not being spotted before close range if a target isn't on high alert
~ Something which looks like a freefall bomb is not going to survive a ballistic re-entry and if it could then you might as well make it a warhead-free ortillery round and just hit the target with a lump of bonded superdense moving at orbital speeds.

Obviously they're useful for close air support for in-atmosphere fights.


Probably more relevant is the concept of 'modular' weapons. Having seeker heads, manoeuvring drive fins, main drive tail sections and warheads all be 'interchangeable' components built to common standards gives you a lot of flexibility - firstly your fleet armourers can assemble nukes, standard missiles, multiwarhead missiles or whatever as the mission requires, but also you can store the components more safely (a fuze, by definition, has to be pretty easy to set off even if it's not too powerful, so being able to store it physically removed from the warhead is a basic safety principle) but you can have different manufacturers provide you with bits as needed and as manufacturing capacity is available.

TL12 missile drives are obviously going to be 'worse' than TL15 missile drives, for example, aside from one key virtue - the system fleet dump is full of the bloody things and you can take and use them to rearm NOW instead of waiting a fortnight for a sector flee depot ship to turn up...
Understand that I'm not advocating violence.
I'm just saying that it's highly effective and I strongly recommend using it.
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Re: Ship Design Philosophy

Postby Condottiere » Mon Dec 17, 2018 5:41 pm

We did have a modular missile design sequence, i'd argue that short/mediumish duration ordnance would still use rockets as propulsion.

Part of the problem with modular is that if you use a standard launcher, everything has to be plug and play, compared to attaching them to wing pylons or a bomb bay.

As regards to sandcasters:

1. I think their potential is criminally under-used.

2. If I understand their range correctly, it's adjacent.

3. However, I'd dogfight and close to touch, and unload the entire magazine, if possible.

4. It's basically my vision of dive bombing in space, or

5. Close ground support.

6. If I were the opposing commander, my big fear would be if sandblaster armed fighters broke through and went after the baggage train, as opposed their more nimble escorts.
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Re: Ship Design Philosophy

Postby Condottiere » Tue Dec 18, 2018 11:48 am

Speed of a freefalling sandblaster in space would be velocity of the dispensing spaceship, plus whatever boost the sandcaster launcher gives, if shot straight ahead.

On the other hand, as a caltrop mine, dropped in the path of the pursuer, you'd also want to minimize the time the other ship has to react.
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Re: Ship Design Philosophy

Postby Condottiere » Thu Dec 20, 2018 12:49 am

Spaceships: Engineering and How Does a Star Destroyer FLY in Atmosphere?

Ever wonder how a massive Imperial Class Star Destroyer can fly in atmosphere? How does it survive entering a planets gravity well and flying out? Well we take a deep look at the science (space magic) of the star destroyer.

https://www.youtube.com/watch?v=IYEm7Rq5fEs


1. Repulsor lifts

2. Inertial compensator bubble

3. Twenty three hundred gravities acceleration
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Re: Ship Design Philosophy

Postby Condottiere » Thu Dec 20, 2018 4:55 pm

Spaceships: Drop Ships

A common vehicle in Military Science-Fiction: A Drop Ship is a craft used to carry troops, vehicles and/or supplies from an orbiting ship to the surface of a planet or natural satellite and back, sometimes while under fire. Some are effectively a Military Mashup Machine between a space shuttle and a transport helicopter, while others are full-sized landing craft that are substantially larger. If the ship is armed and/or the troops involved happen to be reinforcements, it may be the vehicle of a Gunship Rescue. Drop ships can go by may different names. These include, but are not limited to: drop ship, assault shuttle, landing craft. In a proper sci-fi setting, the size and configuration is limited only by the author's imagination.

Truth in Television, given the fact that the physical requirements of "getting from a planet to orbit and back" are far, far different than those of "getting from orbit around one planet to orbit around another". Think of the lunar lander as a kind of Drop Ship and you'll get the idea.
For when the vehicle is not designed to go back up, see Drop Pod. Sometimes, deployment results in a rain of men.

...

One of the most famous, if not the Trope Maker, is the dropship from Aliens. The ship (maybe) and its pilot (definitely) were inspired by Starship Troopers, though the preferred method in the book for deploying the Mobile Infantry was literally to drop them from orbit. However, drop ships were used when the deployment was on a more relaxed schedule, and ships were used to take the MIs off the planet. The movie, though, played it straight.

...

Averted for Rule of Funny in Futurama.
Captain Zapp Brannigan: As you know, the key to victory is the element of surprise. [presses Big Red Button] Surprise!
[bay doors open under soldiers, dumping them onto the planet below.]

...

The closest real-life equivalents to this trope are military gliders. Granted, these works only in atmospheric conditions, but it was an accurate and pretty reliable way to get airborne soldiers and heavy equipment, such as artillery and vehicles, where they were needed. Unlike normal gliders, they did not truly soar, and had to be cut loose from their carrier planes a short distance from their destination. They were only used during World War II, after which they were replaced by helicopters.

As mentioned above, the Lunar Lander used in the American Apollo missions could be considered a dropship at its most basic, simplified elements: A vehicle capable of transporting people and cargo from an orbiting ship to the surface and back again. Granted, however, that the complete Lunar Lander does not return, only the crew compartment, and as such the lower portion of the Lander along with any cargo is left behind.

Almost-Real Life Example: The Small Unit Space Transport and Insertion concept of the U.S. Marine Corps is a serious proposal (though one not likely to become reality any-time soon) to deploy Marines to anywhere on Earth via a small sub-orbital Space Plane. The flight profile would be similar to that of a military glider, but with a portion of the time spent in space under rocket power.
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Re: Ship Design Philosophy

Postby Condottiere » Fri Dec 21, 2018 7:58 pm

Spaceships: Bridges, Space Stations, and Command

I was re-examining space station design, to see if I could pull out any chestnuts from there.

A command bridge can be installed in military space stations, and are capable of commanding fleets across an entire system. A bridge on board a space station can be given command bridge capabilities by doubling its cost. It functions as a normal bridge but also grants Dice Modifier Plus One to all Tactics (naval) checks made by Travellers within it.
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Re: Ship Design Philosophy

Postby Condottiere » Sat Dec 22, 2018 11:54 am

Spaceships: Bridges, Space Stations, and Command

Actually, that could just mean adding another hundred kay schmuckers per hundred tonnes of hull.

Space station bridges wouldn't be able to do astrogation, and piloting would be pretty crappy, beyond sort of being to handle just a little waggling around; however, nothing against using them as a pure fire control, internal security, engineering and command centres.
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Re: Ship Design Philosophy

Postby Condottiere » Sat Dec 22, 2018 2:15 pm

Spaceships: Engineering and Budgetted Solar Panelling

At a hundred kay schmuckers per tonne, it probably doesn't matter.

But since minimum tonnage is half a tonne, and if you don't need that large a coverage, efficiency is lowered by twenty percent, and that means it costs thirty thousand schmuckers, instead of fifty, saving you twenty thousand, which in the scheme of things isn't a lot, though perhaps for more private users it would.
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Re: Ship Design Philosophy

Postby Condottiere » Sat Dec 22, 2018 5:01 pm

Spaceships: Engineering, Jump Drives, and Narrowing Down Range

There are three possible answers:

1. jump factor exactly and below

2. mathematically, jump factor plus forty nine percent of a parsec, and

3. Interstellar Wars, jump factor plus a quarter parsec.

I'm inclined to favour an Interstellar War interpretation of this, not because it seems a compromise between the other two possibilities, but primarily because in two weeks you could jump three parsecs with only a factor one jump drive.

Next up, I beieve that one way to control more or less exact jump range is by feeding the jump drive a precise amount of energy pro rataed to the exact distance calculated between the entry and exit points of the rabbit hole.

Since jump drives require the same amount of fuel regardless of how much the distance varies from the general parsec range, specifically experienced in insystem microjumps, this is not an issue.
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Re: Ship Design Philosophy

Postby Condottiere » Sat Dec 22, 2018 7:34 pm

Spaceships: Engineering, Jump Drives, and Narrowing Down Range


Or,

You have to have the required percentage to jump that far, as well as the additional the power boost, though the technological level limiter permits that extension to twenty five or forty nine percent of a parsec.

Of course, it would help if we knew the exact distances between destinations in order to extract the maximum usage of this mechanic.
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Re: Ship Design Philosophy

Postby Condottiere » Sun Dec 23, 2018 10:48 am

Spaceships: Engineering and Customized Solar Panelling

.. Solar panelling
... technological level
.... nine
... tonnage
.... half a tonne
... output
.... power plant
..... rated fifty scotts
.... power plantless
..... virtual fifty scotts
...... one hundred and sixty six tonnes
... cost
.... 50'000 schmuckers

.. Solar panelling
... technological level
.... nine
... budget
.... increased size
... tonnage
.... half a tonne
... output
.... power plant
..... rated thirty seven and a half scotts
.... power plantless
..... virtual forty scotts
...... one hundred and thirty three tonnes
... cost
.... 30'000 schmuckers
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Re: Ship Design Philosophy

Postby Condottiere » Wed Dec 26, 2018 11:08 pm

Starships: Hulls, Armouring and Planetoids

Some time ago I had calculated that the formula for nickel iron armouring factor was five percent plus seven and a half per factor.

I was trying to reconcile interstellar costs between planetoids and standard starships, when the thought came to me that I'd gladly sacrifice an armouring factor in order to retrieve seven and a half, or even five percent back for planetoids.

Then the thought hit me, perhaps spaceships actually do need a minimum of armour factor two in order to operate in deep space.
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Re: Ship Design Philosophy

Postby Condottiere » Thu Dec 27, 2018 7:46 pm

Starships: Engineering, Fractional Jumping, and Fuel Usage

So, I've ended up with a jump drive that has a performance of one hundred and eighty parsec tonnes. What can I do with it?

Well, if I had a one hundred and eighty tonne hull, I can jump one parsec with a fuel usage of eighteen tonnes; or I could microjump, and still use eighteen tonnes of fuel.

If i had installed this on a default scout, I could jump one point eight parsecs, which might be a tad shorter than the distance to an neighbouring starport, and use up eighteen tonnes of fuel.

If a free trader had one of these, they'd only jump ninety percent of a parsec, though they'd still use twenty tonnes fuel. The rules are quite clear on this, the minimum default fuel usage is ten percent of volume. Which could correspond with a default minimum of ten tonnes for a jump drive.

However, after one parsec/ten percent fuel usage, that percentage can be pro rataed.
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Re: Ship Design Philosophy

Postby Condottiere » Sat Dec 29, 2018 4:09 pm

Spaceships: Armaments, Railgun Spinal Mounts, and Steel Ball Bearings

One interesting aspect of modifying the size of ordnance based weapon systems is how this effects the ammunition, which is why I've always drawn the distinction between the launcher and the missile.

You can squeeze in a smaller missile into a larger launcher, but unless it's like a spigot mortar, not a larger missile into a smaller launcher.

It would be interesting to know what precise material the ammunition for railgun spinal mounts is made from, since I'm pretty sue I can mine nickel iron ones from asteroids a lot more cheaply. And even if it turns out crystaliron, the nickel iron ones look like an interesting cheaper alternative.

Going through the technological level based modification process and ending up with larger, though same damage potential causing ammunition, would that mean the manufacturing process spat out balls that had a larger volume, but were less dense?

Things to consider.
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Re: Ship Design Philosophy

Postby Condottiere » Sun Dec 30, 2018 11:42 am

Starships: Planetoids, Wasteage, and Transitional Cost Accounting

On the tactical level, planetoid hulled spaceships operating within a well established infrastructured environment, are probably the best bang for buck warships; commercially, ordinary spaceships can only compete by removing the gravitational plating.

Now, my view is that armouring tends to cost the same, with some minor variations, regardless of the hull shape, more in terms of actual tonnage used. Neat thing about planetoids is, it's based on a percentage of the cost of the hull, which for all intents and purposes is peanuts; while I'd dispute that the actual amount should be based on the non wasteage displacement, in terms of cost it isn't an issue.

Likewise, you can use the total amount of tonnage of the planetoid as hardpoints, meaning your density of fire certainly equals that of comparable standard hull ships. Get a hundred kay tonne planetoid, reinforce it, and pound for pound, it can take more pounding than a battleship.

Despite disadvantaged by being unable to skim a gas giant for fuel, normal operations tend to make fusion plants only sip at the brims of their bunkerage, which can be well extended by extending solar panelling, so the tank only needs occasionally filling up.

It's when it comes to jumping, that extra twenty percent does cost you in terms of a larger hyperdrive, and more fuel requirement. The only way that can get squared is there's a jump tender specifically assigned to two or three planetoids, passaging each individually, which would tend to favour rather long term military planning.

Commercially, it would be a rather barebones operation, basing it more on minimums dictated by the rules, rather than tonnage optimizations. You don't have to power wasteage, just the remaining four fifths of the ship, and even that could be limited to fragile cargo, vital ship systems, and personnel quarters.
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Re: Ship Design Philosophy

Postby Condottiere » Sun Dec 30, 2018 11:43 pm

Spaceships: Heat Shields - Things Kerbal Space Program Doesn't Teach

The science of Aerothermodynamics covers what happens during a spacecraft's fiery flight through a planetary atmosphere as it sheds speed, converting kinetic energy into thermal energy. This represents a complex interaction between fluid mechanics, thermal radiation and chemistry.
The engineering required to shield hardware against this intense heating is an equally complex multi disciplinary art.

https://www.youtube.com/watch?v=hLHo9ZM3Bis


Apparently, not an issue for manoeuvre drive equipped spacecraft. Though lifters are cheaper than coating the vessel with heat shielding.

How deep do you have to dip into a gas giant in order to skim that milk cow?

Could add parachutes, to either land the spacecraft, or slow it down on landing.

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