SaturnianBlue

Um... What?!?! 168 kts=~193 MPH... (If true, Maria is the strongest storm in the atlantic ever)... Edit: Keep in mind this is a Dropsonde, which is more reliable than the SFMR instruments that get rain-contaminated a lot.

Now upgraded to 909 millibars and 175 mph winds—10th place for lowest pressure in the Atlantic basin, kicking Ivan and "Cuba" off the list.

Testing my fusion passenger ship, with a Kerbin-Jool run.

Yep!

The Hurricane Hunters have flown through the pinhole eye of Hurricane Maria, and what they've found is a monster category 5 hurricane with a pressure of 925 mb... Not since 2007 have two category 5 hurricanes occurred in the same season. Raw Dvorak intensity estimates have put the storm at 7.4—an absolute monster. Edit: And we posted the same thing at the same time! D'oh! Edit 2: And it is official—the NHC has nailed Maria down as a 160 MPH storm at 929 mb. The storm is about to strike Dominica, which is likely still recovering from Erika in 2015—not since David of 1979 has such a powerful storm struck them.

It looks like a dustbin with a whisk, so this most certainly counts!

Yikes! Maria is now just shy of category 3 status with a pressure of 967 mb. The HWRF has a category 4 passing east of PR. I'm not sure what's with the ECMWF—it seems to have initialized at way too high a pressure, but even it forecasts a lot of strengthening, that's for sure. No visible eye on satellite, but it shows up distinctly on radar. Jose looks like it is transitioning to an extratropical cyclone, but that doesn't mean it won't create a lot of wind.

Norma has weakened, and is turning away from Baja California. Jose maintains 90 MPH winds, and while it looks like it'll stay mostly offshore, it does have a considerable wind field. Lee... Is practically nonexistent. Otis is officially a Major—a real shock considering the storm had finally become a tropical storm yesterday after 5 days of being a tropical depression. Coincidentally, I was hoping for a nice "fish storm" in the EPAC, instead of a dangerous Atlantic storm... Unfortunately, only half of that wish was filled, because... Maria continues to strengthen, with a powerful core of very cold clouds, and it is almost certainly undergoing rapid intensification. A category 4 over Puerto Rico is likely, and considering the fact that Irma missed Puerto Rico, yet power outages from that storm are still being repaired, this is even more concerning than it already would've been.

Nice report! The effort really shows, though you did get the Isp thing mixed up in the engine section. I quite enjoyed the crew member files.

NHC has actually held Jose's strength at 70kts though. Maria has already become a 50 mph storm, and rapid intensification not only seems likely, the NHC is already predicting a category 3 in four days, with them straight up saying that RI is likely. I fear a repeat of Irma. Lee remains a weak storm and Norma in the EPAC has weakened. TD 15-E is finally TS Otis.

The Ship Design Process I In this next set of chapters, we’ll explore the steps to designing realistic, functional ships in KSP. Setting The setting of where this ship is being designed is everything—it’ll determine the ship’s purpose, and it’s design. For this chapter, i’ll design just one ship—hopefully, you’ll be able to apply the steps to your own design. So let’s start! The Kerbals have spread out to the many planets of the Kerbol system, with millions settling the surface, the air, and space, with corporations and countries settling. Kerbals have yet to unlock the power of high-g, high delta-V fusion rockets, but perhaps soon... Purpose Since I haven’t covered space warfare, yet (I can’t get BD Armory to really work, for one thing), this design will be a civilian one. By this point, most interplanetary freight is probably launched by mass drivers, and many likely take advantage of Hohmann transfer orbits—the supply of many resources is likely to remain consistent, barring major changes that would likely be anticipated. Perhaps a few products may require more gentle accelerations, such as electronics and especially complicated equipment, but these can simply use longer mass drivers, or freighters, which can afford to take a fairly slow route. So where does this leave us? Passenger ships. Most people travelling between the planets aren’t going to bother with traveling for hundreds of days—they would much rather prefer paying higher for a quicker trip. Though this is bound to take more propellant, it would save some mass on food and other various amenities. This ship should be flexible enough to travel different routes, according to demand. Let us put some requirements for this vessel. -Must be able to reach Jool in at least 75 days -Must have enough thrust to operate inside the planetary systems themselves -Carry at least 1000 passengers in comfortable condition -Avoid the use of particularly expensive materials -Modular capability, allowing a freight setup Payload We will begin with the payload, as it is what the rest of the ship will be built around. The payload? 1000 passengers and whatever is needed to support them for an extended period of time. In order to find the needs of the passengers, I turn to the Kerbalism mod for help. For a 70 day trip, the water and food a kerbal requires adds up to around 300 kg. Considering this has to be multiplied by 1000, this means that the rations alone will be 300 tons. A more obscure factor is the volume required so that passengers don’t experience psychotic breaks. A NASA report suggests a minimum acceptable net habitable volume of 25 cubic meters per person, but because kerbals are smaller, I assume that they can afford to live in smaller quarters. Kerbalism suggests that the space available would be 40 cubic meters, but I reckon that to be much too inefficient—this isn’t a cruise ship, we’re just trying to get people to be where they need to be! Instead I go for around 14 cubic meters. With Kerbalism, I find what it takes for the passengers to be comfortable, and how much tonnage would be required per kerbal. This was done with a small sample of 9 kerbals, since doing this on a scale of a thousand passengers is very time consuming. The result? Around 2.8 tons. I would imagine that due to the economies of scale, this would be significantly reduced when the amount of passengers is on the order of a thousand. Additionally, inflatable habitation space would significantly decrease this, but the same mods that add such habitats (MKS, Tokamak Industries) are the very same ones that cause the game to crash. Factoring that in, I therefore presume the tonnage will be closer to 2 tons. This gives us a result of around 2 kilotons. Now for the volume. Since the volume is about 14m3 per person, we end up with 1000 times that. Of course, this ignores the used space, which is essentially everything else. Inflatable habitats would be even more helpful for boosting space, so theoretically the kerbals could have much more for less. To be on the safe side, I will assume that the used space will be as much as 50% of free space, since I’m not exactly sure how much space will be taken up. This leaves us with 21,000 m3 of space, or approximately a cube 28 meters on each side. I know, it looks rather flimsy... We will split the habitable space in two, as we are putting the passenger sections at the end of two arms of a centrifuge. Since a variety of passengers from many backgrounds are likely to ride on this ship, we will keep the spin gravity at 0.3 G, which should be tolerable for kerbals who lived on worlds like the Mun, while assuaging the effects of zero-G. While we want to reduce the nausea induced by the Coriolis effect, we also do not want the arms to be too long, since this would increase the mass, and force the ship to be longer, in order for the arms to stay in the shadow shield (I’ll explain that later). Passengers should be able to adapt to 2 RPM with no problem, and achieving that with 0.3 G gives us an arm radius of 70 meters. On the end of this, we will mount the habitation modules, which will be connected to each other by a long, pressurized tube running the entire length of the arms. Propulsion What we are looking for in propulsion is something that can produce lots of thrust when necessary, but also capable of very high velocities, so the distant planet can be reached in a useful amount of time. Electric propulsion produces low thrust and fairly mediocre exhaust velocities when considering such a thing. A solid-core nuclear rocket produces a lot of thrust, but they have low exhaust velocities. Gas-core rockets provide a fair load of thrust, but they have a fairly low Isp. That leaves us with fusion. As the setting has noted, thrusters like the “Kerbstein” drive are still out of reach, further narrowing our best choices to the VISTA and the Tokamak. The VISTA engine produces excellent thrust, and an Isp of 15,678, which can be increased to 27144 in return for lower thrust. On the other hand, the Tokamak can produce decent thrust, but can adjust the Isp from around 12,000 to nearly a million in return for lower thrust. In terms of performance, the Tokamak is the better option, as is more flexible in terms of delta-V, and therefore the destination—a close destination can be reached quickly by increasing the thrust, while distant targets can take advantage of the higher exhaust velocity, all for similar amounts of fuel. Additionally, the VISTA performs best with Deuterium-Tritium fusion, which is the easiest to achieve, but also the one that produces the most neutron radiation. For a more exact, precise method of finding the best Isp, acceleration, and delta-V for a mission, I highly recommend this. Keep in mind that I chose a rather arbitrary size for the reactor—we'll have to adjust that later... This passenger vessel will use liquid hydrogen—not only is it the only fuel usable with the magnetic nozzle part, it is the most efficient propellant available, something that is particularly valued on a vessel that needs to achieve as high a velocity as possible. The propellant is necessary for achieving the higher thrusts. Electricity, Radiators, and Radiation Shielding The torus reactor that is utilized for propulsion can also be used for electricity generation. Electricity is provided with the help of a magnetohydrodynamic generator, which operate at high temperatures with no moving parts, and uses some of the plasma in the Tokamak and converts the heat into electricity. KSP-Interstellar allows various types of fusion to be used in this specific reactor, leaving us with a few options. Deuterium-Tritium is the easiest to achieve, but without the use of a neutron-absorbing shell (which I presume aren’t modelled in the mod), much of the fusion energy is wasted in the form of neutrons. Deuterium-He3 produces considerably less neutrons, but the amount will still necessitate the use of a shadow shield, and the rarity of Helium-3 makes this a less economical option, and limiting the routes of our vessel to just locations with considerable deposits of helium-3, or huge fusion reactors. Though Deuterium-Lithium fusion requires a very high temperature to occur, we will use it, as it produces the least amount of neutrons. It also produces the most thrust in-game, for the same mass reactor. A fusion reactor generates considerable waste heat that must be removed, or the spacecraft will heat up, melting the ship. With no way to conduct or convect heat in space, our vessel must use radiators to get rid of the waste heat. Due to the laws of thermodynamics, the radiator coolant cannot be hotter than the system itself, and certainly not as hot as the melting point of the material. While there are many types of radiators, the ones in-game appear to be solid radiators. In a nutshell, such radiators are small pipes that pump in hot coolant in and cooled coolant out, before returning back to the system they cool. Since fusion reactions take place at very high temperatures, we do not have to worry about the radiators being hotter than the thermal source. An assortment of radiators. The radiators from KSP-Interstellar are either made of graphite, graphene, or titanium. Since the graphite/graphene radiators are capable of operating at a higher temperature, we will choose those. In-game, they can operate at temperatures as high as 3700 Kelvin. To be on the safe side, I will go with a radiator that operates at 3000 Kelvin. Despite the gigawatts of heat produced by the reactor, this ensures that the radiators do not have to be very large and heavy, which can be the result with some nuclear reactors (especially in Children of a Dead Earth…) The passengers on the vessel create a lot of heat, which must be radiated away at room temperature, requiring particularly large radiators despite the heat only being in the range of a few hundred kilowatts (an estimate I took from Children of a Dead Earth, though a Kerbal’s small size means less heat is generated compared to that of a human). Though this factor is not actually accounted for in-game, I managed to find the amount of radiators I would need by sticking on some “Blanket Photovoltaic Solar Power Receivers”, which generate about the amount of heat (630 KW) I was looking for. I then added enough radiators to drop the radiator temperature to about room temperature (294 K). Usually the weight of the radiators would be around 2 tons or so. Though fusion reactors located on the surface or in space stations can afford to heavily shield their reactors, this cannot be said of spacecraft, where each gram counts. “But,” you might say “then the crew will be exposed to the radiation, yes?”. That’s true, and this is where the shadow shield comes in. They stop the gamma and neutron radiation released from the reactor, particularly on the top side. This will not protect nearby vessels, but it does a good job of protecting the crew. Despite the fusion type, we still need some radiator protection. The structural pylons mark the "shadow" created by the "shield" represented by an adapter. The radiators and the propellant tanks are angled to fit inside the shadow shield’s protective cone. Why? Exposure to neutron radiation can cause the structure to embrittle, seriously weakening the integrity of the ship. Another threat is neutron activation, where a neutron is absorbed by a harmless isotope and is mutated into a radioactive one. The crew will not be protected from the shadow shield from that danger. Another way we can lessen the danger of radiation will be by placing the propellant tank in between the reactor and the kerbals, since doing so basically puts more stuff in the way, which is basically how the shadow shield works, too. Structure In order to help reduce the radiation exposure the payload (passengers) experience, they will be mounted at the front of the ship, significantly far away from the reactor. This also increases the diameter of where the shadow shield’s protection is effective, which will be especially useful later. This will require a long truss section, but a lightweight material like aluminum graphite/epoxy should provide the strength to support the vessel, while amassing a few tons. In-game, I will represent the truss with the KSP-I E truss, which is similarly light. Command There is little for a crew to do during the long interplanetary voyage, so it therefore makes sense to automate ship operations, perhaps by utilizing AI. The mass savings associated with this would be significant. However, there may still be a need for crew, in the form of flight attendants, in the case that robots and AI are still incapable of serving the functions of these jobs. For better or for worse, having a crew will probably best for a story, as kerbals will probably be cared for more than an AI. Communication Two for redundancy! Fairly straightforward. Since this vessel is meant for a variety of interplanetary destinations, the transmitter must have a high range, and with many kerbals onboard, data transmission must also be high. For those reasons, the vessel will include large communication dishes. Control The powerful fusion engine onboard would provide significant thrust for gimballing, but operating the fusion engine near populated areas would place many in harms way, so we must seek alternative methods for control. Reaction wheels are a popular method of turning in stock, but they are considerably overpowered compared to their real-life counterparts. The monopropellant reaction control system is an alternative, but this requires the storage of another fuel, one that is very reactive. The best choice for maneuvering is likely a resistojet or an arcjet. Both use electrical power to heat a propellant, and because the fusion reactor produces a tremendous amount of electrical power, we can use some of it for this. I choose to use arcjets, since they can reach a high exhaust velocity. Both can use hydrogen, which is already used for the fusion rocket, negating the need for the storage of more fuels. Docking Ports This shot shows the docking port, the arc jets, the AI, and the antennas. This is probably required for this ship—I don’t see any good way the kerbals would get out of the ship, much less get in! Going with a sensible design, we will place the docking port right above the centrifugal arms, so passengers are not required to move very far, and can actually get out (KSP lets you put docking ports anywhere, even next to the engine). We will also place small docking ports on the propellant tanks, to allow tugs to push the vessel a significant distance away from the station. After a few modifications, this is the finished result. Next time, we’ll put the vessel into testing to find the shortfalls, and the typical operations of the ship. Thanks for Reading! Next: The Ship Design Process II

It's happened before with Hurricane Luis and Marilyn in 1995—the two storms struck the Leewards within 2 weeks of each other. I'm not sure how Jose would intensify like that.

Tropical storm Lee has formed, but will likely pose no threat to land as it remains a weak storm over the course of the next few days. The bigger threat is PTC 15, which is likely to become Hurricane Maria, heading towards the very areas that were devastated by Irma in the Leewards. I think it's far too early to debate the impacts on the US or the intensity, but we could very well have a major hurricane. @ProtoJeb21 Seems unlikely... The NHC forecast for a Category 1 storm that gradually weakens is far more likely in my opinion.

Quick sketch of Cassini I put together.

Nearly done with the next chapter—here's the ship that was built for it.

Working on an interplanetary passenger liner fusion rocket. Interesting details include the trimming of the fuel tanks and radiators to fit in the shadow shield, and two boxes, meant to represent the passenger modules.

I don't remember a time when Cassini wasn't at Saturn—that's how long it has been around. I suppose Cassini will burn up in the great Saturnian Blue, so to speak...

Active tropics today: Hurricane Jose has weakened to a tropical storm, and has a some chance of affecting the eastern coast of the US as it begins to trek northwards. Still looks like a big blob. The East Pacific is busy again, with hurricane Max showing up, having intensified rapidly as it nears the Mexican coast. It also looks like a blob, but an eye showed up on satellite. Tropical storm Norma has also showed up, and is heading north, and is forecasted to become a hurricane. TD-15 E is still active, and could become a tropical storm. In the West Pacific, Typhoon Talim peaked as a category 4 before weakening to a category 2. It's got a distinct, giant eye, but it's convection is shockingly low. It's headed towards Japan. There's also Doksuri, which is intensifying, and is headed towards Vietnam.

On the West Coast they're still called hurricanes, actually.

Hurricane Irma is now a low-end category 2, but the wind field expanded dramatically—tropical storm force winds almost stretch from Key West to South Carolina! Jose is a low-end category 3 and will weaken, but the storm stalls at that point. At this point it is far too difficult to predict what will happen, but a loop like Hurricane Jeanne did back in 2004 could happen (emphasis on "could"). After that, the tropics might finally settle down a bit—there's a tropical wave out in the atlantic, but even if it forms, it'll be far from land for the next week. The East Pacific has 3 areas of interest for formation, and they all seem to overlap each other. I'm curious to see what comes out of that. The East Pacific was really active in July, but it seems to have really quieted down since then.

It's still a category 2 with winds of 110 mph at 940 millibars that'll bring tropical storm conditions as far as Atlanta. Besides, it hasn't gotten up towards Tampa yet, and there's more damage to come with more rainfall and the storm surge.

In my opinion, the damage to the Leeward islands would be enough to get the name Irma retired, whether or not it hit Florida. Also, there's webcam footage of people taking selfies down in the Florida Keys, even though big waves are already crashing in... Edit: Irma looks to be strengthening again...

Irma is down to category 3 status, but the warm SST could strengthen it back to category 4. Even if the intensity remains stable, the storm surge could still be a very big threat. Any possibility of a New England strike by Jose is still over 10 days out—10 days ago, Irma had just formed. I would say that model predictions beyond a 5 or so days out shouldn't be taken too seriously.

Hurricane Irma is back up to category 5 status, despite scraping along the Cuban coast. This seems like a Donna 2.0 scenario, with the hurricane traveling along the Florida west coast and the keys. In my un-official, totally instinct-based opinion, Irma will landfall as a category 4 like Charley, but much bigger, leading to hurricane force winds across much of the peninsula. I'm under the impression that the GFS model is unreliable. Hurricane Jose is the strongest a category 4 can be, and while an OTS (out-to-sea) scenario is likely, it won't be before the leewards take yet another beating. Hurricane Katia has been heavily weakened, but it nonetheless poses a threat to Mexico.

That's a much smaller discrepancy than I thought. That is why the Loftstrom loop is built over the ocean, yes? Besides, building it near land would favor certain areas/states over others, and the ocean is usually seen as being international, preventing such conflicts. It would make it a remote location and may require a floating runway capable of servicing passenger jets, but this shouldn't be a challenge compared to the loop itself. I'm fine with the stream-rider taking a while, I can always go back and edit the post later. Is there anything on Deuterium-Lithium fusion? It appears to be aneutronic but I haven't read much on it. There isn't an option for boron fusion in the reactor i'm looking at, so I suppose Deuterium-Tritium is the easiest, but it does require a thick shadow shield, while D-He3 is expensive. If the D-Li fusion isn't effective, i'd imagine D-D fusion is the best, since there is no concern of half-lives, while the fuel is fairly common and cheap to use. When I was thinking of the engine design, I was looking at the Discovery II concept and one of the engines from the fusion engine post I made a while ago. Perhaps I did a disservice by referring it as a "Tokamak", since spherical torus reactor would be more accurate.