Monday, October 5, 2015

KSP: Keystone Crew Delivery Vehicle.

So, as much as I like to cobble and tinker with Kerbal Space Program, there is a method to my madness as I juggle parts around. One of the things that I like about the program is that it lets you address the same type of issues that the National Aeronautics and Space Administration, the Russian Federal Space Agency, and the Chinese National Space Agency have to deal with each day. While the US arguably has the most advanced space program currently going, I am much more drawn towards the Soviet/Russian Soyuz program and its overall engineering philosophy. I am also a longtime fan of the KSP mod Home Grown Rockets. I have flown a great many missions with the Kerbal "Soy Juice" command capsules fitted with "onion" pods, and have built several large and complex space stations around the craft's abilities.

Something to note, the Soyuez works on a very dependable, but disposable working principle. When launched, the craft itself is composed of three parts, the "Orbiter Module", the "Reentry Capsule" and the "Service Module". of the three components, only the Reentry calsuel comes back to earth, and even that is a rough entry. The whole craft is a one-time use, and can carry only three people.

If you're interested in some more details on the craft and it's functions, I highly recommend the ESA's videos on the Soyuz Launch, Docking, and recovery.

In the late 80s, and through the first decade of this century, the RFSA was heavily invested in research into a replacement for the Soyuz craft, with a heavy emphasis on reusability, as well as a less violent reentry back to earth. One of the more prominent designs to come out of the project was the Kliper. Using lessons learned from both Soviet/Russian space experience, and a new partnership with the European Space Agency, the Kliper was seen as a larger, more effective means to move men and equipment into orbit around the space station, and also take on additional missions like satellite position, orbital repairs, and other scientific research.Funding, however, was the undoing of the design, and the ship is still stuck in the design phase with no funding for advanced development.

I was drawn to the kliper design because it uses a classic rocket to reach orbit, but also uses airfoil/glider design to return to each in a much more complete way than any of the Russian predecessors. Also, by using a glider, rather than a bell (the shape of the reentry module on the Soyuez), the return is actually far less traumatic and more controlled.

Early Kliper concepts made the craft out to be a super compact space shuttle, complete with landing gear. Later designs, however, incorporated lessons learned from Russian experience in hard landings (Landings on ground, rather than water) and created a much lighter craft that could glide to a safe speed, and then deploy a large parachute for the final stage of the decent.

Again, the major design point here is the complete reusability of the entire craft. Rather than having to rebuild a completely new vessel  each time, the kliper can be inspected, refueled, and set atop a new rocket. The advanced computers, avionics, radars and instruments are preserved for another mission.

I have dabbled in a fully functional, rocket launched space-plane before, but never liked the results. The parts available in KSP were just limiting enough that I wasn't able to build something that both worked and didn't look unbelievably ridiculous.

My most recent project, however, took some of my lessons learned, and a new take on design philosophy,

My goal, I reminded myself, was not to build a passenger-capable version of the X-15, and while the klipper was not actually within my grasps, a controlled reentry and parachute landing by a lifting body craft was. At the end of the day, I wanted something that could carry at least 3 crew, reach orbit, and return with most (or all) of the instrumentation, control systems, and air-frame intact.

There really wasn't any debate on what from factor to start with. The Mk 3  (space shuttle) set was too large. If I went that route, I'd be looking at rebuilding a full shuttle, which is what I specifically didn't want to do. Alternately, the Mk 1 command pod was too small (crew of 1) and had no lifting body abilities. In point of fact, the Mk 1 would be a step backwards in every sense of the word. So, that left us with the Mk 2 series of parts.

The Keystone CDV (Crew Delivery Vehicle)

I drew my name from the Soyuz, which is Russian for "union". "keystone seemed to work for what I was looking for.

Vessel information
Weight: 8.0 T
Length (nose to docking ring): 7.4m
Width: 2.7m
Delta V: 919 (atmo) / 1160 (Vac)
Crew: 0 (Drone control unit)
Passengers: 4
4x 24-77 "Twitch" Liquid Fuel Engine

The Keystone is capable of transferring 4 passengers into high Kerbin orbit, but does not have the thrust (by itself) to transit outside of orbit and move to another body (Mun or Luna, for example). Its primary mission is the reployment and return of crews to other orbital facilities, or waiting orbital craft deployed in unmanned launches.

The walk-around:
As you can see in the nose detail, the ship uses multiple Place-Anywhere 7 Linear RCS Port thrusters for orbital maneuvering.

I'm using a Mk 16-XL parachute for the nosecone and final recovery system, and the front quarter of the craft is the fuel tank, one of the MK2-to-1.25M Adapter tanks, And that mounts to a MK2 drone core control unit. 

The Mk2 Cargo Bay (CRG-04) is actually serving as a support bay/module for this vehicle. It does not have cargo carrying capabilities.
The bay contains, and Advanced Inline StabilizerFL-R25 RCS Fuel TankZ-1k_Rechargeable_Battery_Bank, and 5 x OX-STAT Photovoltaic Panels. Communications are handled by a single Communotron 16 mounted on a Cubic Octagonal Strut, whcih is attached by the center of the Z-1K. Thefuel for the main engines is conveyed by two FTX-2 External Fuel Ducts.

The rear aspect of the Keystone shows a good perspective of the crew compartment, the docking rink, and the flight controls surfaces, as well as the 4 engines. 

The 4 passengers are carried in a Mk2 Crew Cabin, as I said before. Maneuvering and attitude control is handled by a combination of the Reaction wheel, the RCS system, and the four A.I.R.B.R.A.K.E.S.

The Docking port is projected out past the ends of the A.I.R.B.R.A.K.E.S. by an (emptyFL-T100_Fuel_Tank that is used here for a structural tunnel and mount for the 4 main engines. During initial trials, I mounted the docking port to the back end of the hull directly, and the engines to  Cubic Octagonal Struts, but it was quickly realized that during landing, the engines were being destroyed by the otherwise slow impact, the docking port was rated for that type of impact so I let it be the "bumper" for the ship on landing.

This slightly enlarged image gives you a good view of all the critical systems with the control flaps extended into full break mode.

Craft file: Note, this includes the 3 stage launch vehicle. The launch system is a stock reproduction (in concept) of the Soyuz rocket.

Monday, June 29, 2015

Politically what I am *not*

I don't know when this happened, and frankly I don't care.

A long time ago, being "a republican" meant taking ownership of your own deeds first, encouraging economic growth, protecting the right of the individual. It meant a strong, and at times aggressive foreign policy. It meant being proud of the present day America. 

But what passes for the the conservative movement today, and by extension, many of their allies, is little more than a cancerous mutation of the principles I love.

Being responsible for yourself has turned into a cult of "self determination" that stops *just* short of saying anything can be overcome, and by extension all failures are indications of personal weakness. We mock the idea of the government offering assistance to people in need, and we hold up the worst of the worst, a handful of self-indulgent, unrepentant frauds, and tacitly proclaim them as "typical" of all who ask for help from the government. the RNC would have you believe that most people at the warfare office are lifelong leeches, when the fact of the mater is quite different. 

I believe in the concept of a free market economy, and want to see individual ideas grow and prosper, but watching conservative policy on business over he past ten years alone is like watching a nightmare of blind obedience to greed. Statement after statement from local and state leadership ignore, or deny the fundamental facts that prosperous  business in today's day and age are *not* likely to spread the wealth down to their employees. In this economy, with thousands clamoring for work, there are plenty of places, and plenty of small companies who are happy to  pay you as little as they possibly can, and until someone forces their hand, they will not, and realistically can not lift the bottom line without getting slaughtered by their competition. Not all bosses are evil, but just enough of them are selfish enough to keep 'the system" from ever being "charitable" (for lack of a better word at this moment) at a large scale. The idea that 40 hours a week should give you a livable wage should be a point of conversation, not passed off to private industry as "when the economy gets better, the wages will go up".

Likewise, I fully support the right of the rich to get richer, and the right of the individual to make and keep more money. But the more I hear about how few people control the majority  of the cash flow in this country, and how little they play in taxes proportionately, I have to ask when "making money" turned into dodging out of civil duty? I pay my 25% (give or take), why in the hell am I hearing about people paying 5%, 6% or 7% and calling it a day there?

And likewise, in today's environment, money hold a direction correlation with power and influence, and political circles on both sides of the aisle are rife with stories of local and state elections where everyone agrees that someone 'outspent' someone else to get "the word" out.

And just in case anyone wanted some names, start with "the Koch" family, and work out from there.

I don't resent or want to limit the freedom to make money, we are not socialists. But money also carries with it power, and some in power are using their money to limit other's freedom. I'm not saying I have all the answers.... but the dialogue thus far has been shouted down with "they must hate the rich" and "he wants all of your money" whenever the issue is raised.

I support research and scientific development, and when the data doesn't tell such a rosy story, skepticism is appropriate; rigor is part of "the process". But the republican pundits today have made character attacks and bad math their M.O. when talk turns to issues like climate change, environmental conservation and human impact. Personally, I'm convinced that we are hurting the environment, and that our work is changing the overall environment of the planet, but yes or no... when a scientific paper comes out saying that, the responses from the right seldom contain good science... but rather bad one-off examples, accusations of ulterior motives, and cries of "tree huggers". I don't mind a good argument, I don't even mind losing said argument. But why do we insult the process of discovery by STARTING the conversation with "I don't agree with them, so how can I prove they are wrong?"

I have always understood the reluctance to embrace alternate lifestyles and religions, its human nature when addressing things that are new. But today, non-traditional religions and same sex marriage are *not* new, they are not misunderstood, and they are not scary or dangerous. What remains of the opposition to them falls into two categories, the bigots, and the legalistic.

To the first, who in the hell are you to tell adults who they can or can't live with? Who in the hell are you to say what faith can or can't have a sign or a cross or a marker? Who in the hell are we to say "but it's offensive"? The Republic party is lined with bigots. not all of them, and I can't even say its a majority, but with election races running tight every year, the party knows how to get votes, many by appealing to bigots and repressives... they then have to keep that party line going if they want to compete in the elections. They've tolerated the ultraconservative old guard and their ways so long that some of the poisonous "you are not like us so you are dangerous" mentality is making it into policy and decision making. 

To the second. I do not have any doubt that the constitution's balance between the rights of the states and the right of the individual, and the powers of the federal government is a tentative, dangerous, and dynamic balancing act that we get wrong as often as we get it right.
But we a have a whole class of people here who are told at the doors to hospitals, court houses, police stations and even funerals that their rights are not as secure or protected as others.  I have personally seen too many cases were parents, administrators, judges and law enforcement offices have stolen precious time form people who didn't have it to being with. Without proper protection, people can be undermined, challenged, and driven out of vital decision making processes in their own loves, or the lives of loved ones. Does it happen everywhere? No. Is it the majority of times, I don't know, but I will admittedly guess not.  But it's more common that it should be, more common that it needs to be. And most importantly, its nothing, NOTHING but an expression of meanness. Bullying as petty as any schoolyard thug… but done with badges, pens, or official sounding words.

Are we so desperate to protect "states rights" that we will lets states like Oklahoma (who were forced to allow marriage by a court) impose the locally popular interpretation of "right and wrong" on others? I support the right of states and their autonomy… but that doesn’t include discrimination. That doesn’t include letting the majority force themselves on a minority.

Waiting for states to 'come around' of their own accord would likely have left Jim Crow laws in place well into the 90s. Why would we think anything different about  lifestyles and how states deal with them? If anyone want's to let Oklahoma do this on their own, keep in mind that the state has voted (overwhelmingly) to legal jam Christian values down the throats of any resident living in the state. Gay marriage: "threat to our children", religious right (namely inheritances and wills by Muslim in this example): "infiltration by a foreign power"... an so on.
I'm not independent because I am no longer conservative. I'm independent because what I believe is isn't represented by the republicans in the least, and who they pander to  not only disgusting, but dangerous.

I'm all for a strong international presence, I want to see an aggressive display of force, and I am not opposed to shedding blood in our national defense.

But how in the hell we wound up in two counterinsurgency operations in nations with minimal to no infrastructure to build upon, and  populations so diverse and violent within their own realm… is just beyond me. We went into Iraq on a lie. I don't even care who's lie it was, but I fell for it, I cheered them in... then we got stuck going "well now what?" Then the locals who didn't like us did exactly what was done in Vietnam... they used the home court advantage. We went to Afghanistan on a grudge match... we won the first round... but it became clear very quickly that we didn't have a second step laid out... we went in on impulse, one whole nation, madder than hell.... great... then what?

There's a line between "aggressive" and "stupid"... I would submit we were humping that line  like a horny high school senior when Bush gave the "go" order.

I'm all for being proud of the US. We have a lot to be proud of.

But what I see, with my own eyes from the right wing these days, is not *just* national pride, it includes  examples of a brand of ultranationalism reminiscent of tyrannies past. I've seen people want, demand, and even dictate that others: adults, teens, children, *must* be proud of this country. They insist on a pride so absolute that it needs no justification, and so fragile that it can survive no scrutiny or criticism. I've seen books, texts, papers and speeches written and improvised in all forms, defending the country like its existence were a religion, and not a nation. The concept that one can be critical of this nation and still love it is paid little more than lip service by pundits and policy makers who set the tone for the party leadership.

I still shudder at the benchmarks of the progressive movement these 8 years past. the Affordable Healthcare Act was ham-handed, and I'm already seeing some ugly repercussions from it in my own premiums. There was good to it, but I am worried that more people will suffer other ills because of it in place of, or perhaps on top of getting sick.  I'm watching a president and a party treat major shooting incidents as policy points for gun control when the issues run a lit deeper than just who had their hands on a gun.

I'm seeing *both* parties talk out their assess when it comes to human rights and civil liberties. The patriot act and the NSA's data collection just being two examples. 

No, I still don't consider myself a liberal or a progressive. And I still do consider myself a conservative.

But there is a difference between "conservative" and  "scared, ignorant, bully". I just wanted to make sure no one thought me the latter of the two.

Monday, January 19, 2015

KSP: Not exactly according to plan...

Tonight, the game plan was to launch my more developed "Individual Crewed vehicle" into orbit for sustainability trials.

The vehicle itself was actually a good conceptual representation of the Russian Soyuz capsule, and used mostly stock parts.

ICV Km 1
Crew: 1
Engine: LV-909 Liquid Fuel Engine & RCS Maneuvering Thrusters
Reentry: Command Pod Mk1 & Mk2-R Radial-Mount Parachute
Communications: Communotron 16
Fuel: FL-T100 Fuel Tank
OX-4L 1x6 Photovoltaic Panels & Z-100 Rechargeable Battery Pack

Note: the whole idea of the frame is to recreate the utility and the base concept of the Soyuz ship, and to expand on the capabilities of the Stock Mk1 capsule.

And... I wanted something that didn't look american when you looked at it. Call it a stylistic thing.

The ship isn't much heavier than the first manned pod I sent up, so the obvious first step was to build a proton launch platform and mount it there.

ICV launch 1

The Capsule may not have been much heavier, but the additional components made it large enough that we needed to use the next size up of nose fairing in order to completely house the capsule. Thrust to weight, the numbers looked good for a long, steady climb into orbit. 

Unfortunately, the drag on the nose, and the thrust of the second stage didn't add up the way I wanted to. Moments after the boosters jettison, the nose started to drop hard. a minute later, when I should have been pushing 18K meters the altitude started to drop, and before I could react I was at 12K and dropping.

I finally managed to punch the fairings and get the capsuel free of the rest of the rocket. I had just enough time to eject the chute before the altitude went from four figures to three. 
Early splashdown.... You can see the parachute just barely having time to open as the capsule tumbles to the water and the last stage boosters are just about to hit the water at heaven only knows what speed.

All told, the mission was a falure, but the pilot survived and I realized that the proton 1 is an excellent small platform, but I need something with substantially more kick to get the next generation of crews and vehicles. into orbit. 

Wednesday, January 14, 2015

KSP: Crewed flight / Time speed data

Phase 2: Put a crewed capsule into orbit. 

I know that actually putting a Kerbin in space is hardly the dramatic event it was for the Russians, the Americans, or the Chinese. That being said, the mission was still a chance for me to symbolically take the "next step" and see what type of performance my Proton-1 rocket could give me with a crewed payload.

Individual Maned Crew Capsule (IMCC) Mark 1

Well, this certainly won't be making any interplanetary voyages, but the IMCC (mk.1) is a good, one-man orbital craft with a low mass and durability enough to get into orbit and back to the group. This specific unit relies on the internal gyros for maneuvering, and has a small engine for thrust. 

In terms of endurance, I can confidently sustain about half an hour of maneuver, but beyond that I will need additional power sources and probably RCS jets for more precise activities in orbit or beyond. 

The Flight

Fortunately (in game, and out) the mission was more or less as planned, and reached the objective of a 450Km apoapsis before returning to Kerbin for a wet touchdown three quarters of the way around the globe.

IMCC flight on the pad, moments before Launch. 


The ship was under power/thrust for only the first four minutes of the flight, after that, physics carried the ship for the rest of its 22 minute flight. The take-off and lift phase of the flight was smooth and topped out at 2504 meters per second speed when the engine finally cut off, and we reached a peak altitude of 452 KM above Kerbin. 

At the peak of my first crewed flight over Kerbin, 450 kilometers above the planet's surface. 

Flight Metrics

I tracking the flight and its numbers for my own interests, and to see how my Proton-1 design worked under a 1 ton load.

Like I said before, the ship was under thrust for only the first four and a half minutes of the flight, and I track the altitude and speed for that time period. also are the computer's projected Apoapsis at each moment, and I have calculated how far ( as a % of my current altitude) beyond my current altitude the ships inertia alone could carry me at each point of the launch. 

Its interesting to note that the real gains made in altitude are made once the ship crosses the 28K/1000 m/s mark.

       Time  Altitude (K)  Apoap. % of Alt Speed (M/S)
0:30 4.86 7.74 59.4% 231
0:45 7.40 8.24 11.4% 138
1:00 9.45 10.26 8.5% 141
1:15 11.13 11.88 6.7% 183
1:30 13.12 13.87 5.7% 251
1:45 14.65 15.49 5.8% 313
2:00 16.56 17.60 6.3% 396
2:15 18.72 20.12 7.5% 499
2:30 21.29 23.22 9.0% 265
2:43 23.85 26.66 11.8% 759
2:45 24.29 27.28 12.3% 785
3:00 28.00 34.91 24.7% 1055
3:15 33.35 49.94 49.8% 1407
3:30 40.36 93.78 132.3% 2027
3:45 49.30 437.63 787.7% 2530
4:00 59.53 450.50 656.8% 2504

Tuesday, January 13, 2015

KSP: Proton 1

Okay, so I decided to try something a little different with KSO this time. I am deliberately trying to follow a "development plan" with my space program, where I built up to larger accomplishments. I'm not doing Career mode (well, actually I am, but I'm just not blogging about it, its not nearly as much fun for me right now). But, I am retracing the steps of the superpowers in a sense. These baby steps are meant to be 1, more fun, 2, better time management for me.

So, without further delay...

Phase 1. Put a Satellite in orbit over Kerbin. 

The Satellite: Sat #1
A basic communications satellite

1 x 6 solar panels (2)
Gyroscopic mechanism (control ring)
"Stayputnick" command module
Small fuel tank
Small liquid fuel engine
Communications dish. 
Nothing really complicated here, I just wanted a satellite that would stay where I out it, and stay pointed at what I wanted it pointed at. I kept size and weight down as much as I could,

The Rocket: Proton 1

(Note, I am using a lot of Russian influences in my design ideas, so "proton" is no accident in naming)
A basic orbital delivery vehicle, the Proton uses a four-booster solid rocket first stage, and then a long burn liquid fueled booster for the second stage. Third stage is a smaller take with a similar engine. Overall design is meant to get a small payload into a 100 to 130 KM orbit. Early course stabilization is handled largely by the fins, and later on we have a powerful ring gyro at the neck of the ship for control outside of the atmosphere.

 First stage turns over to second stage at about 7KM altitude and the main engine handled the majority of the accent.

By the time the third stage engages, we the rocket has picked up well over 1000 M/S velocity and we are nearing the outer edge of the atmosphere.

The fuel tanks were good enough that we did an orbital adjustment before we deployed, and set the satellite on a diagonal path in order to see more of Kerbin over time.

Final orbit, satalite deployed at 110 KM over Kerbit. 


All told, the mission took me about 45 minutes to do from start to finish. It was a fun reminder of the basics of rocketry and ballistic mechanics, and did feel a lot more like some of those "first steps" I am used to reading about in my history books bout early space flight.

The takeaway:
From an "in-game" point of view, Kerbin just put its first satellite into orbit, This in itself was was a major earth-moving event in actual history.

Much like the Soviet R-7, I have saved the "Proton 1" rocket chassis for use and further development. The hope is to expand the basic design into two or three chassis for light, medium and heavy payloads to orbit before advancing the whole program forward.

And for a side note, the actual proton rocket class  rocket is detailed here. it is actually a late generation rocket design for the Soviets. Myself, I found the rocket's service record and design straightforward, and effective, which is why I am mimicking the concepts here.

Monday, January 12, 2015

KSS Explorer II (Kerbal Space program)

Well, my previous voyage to Mun was certainly exciting, but I promised it would be back, and I followed through on that promise. Rather than build off of my space station, this ship was assembled in freestanding orbit on its own, four central components, two mun landers, and two unmanned drones for surveying work. A crew of 5 and much, much more extensive science, and engineering facilities.
The Kerbal Space Ship Explorer II

The ship is well more than three times the length of its predecessor, with massive fuel reserves, and more thrust compliments of four atomic engines.

The mission profile was much similar to its predecessor, though with a lot more actually accomplished rather than just hoped for. The plan was to launch of Kurbin orbit, reach Mun, deploy two landers at two sites, and send out my surveyor satellites for mapping at the same time. Then retrieve  all of the same and return home. Once again, the game graphics worked well for the mission, and the whole process was just a beautiful adventure.
Exit burn of Kerbin orbit. You get a good view of the
quad-array of atomic engines at 100% throttle.

The Escape burn from earth was a lot smoother this time, with four engines and a more powerful stabilization system in place. The ships was sluggish compared to the smaller "Apollo" type ships that I was used to using, but there was no doubt that I was going to get where I wanted with this thing.

Like I said before, the visuals made the trip well worth the time involved. 

Reaching Mun and breaking was almost easy with the throttle allotted on the ship. 

I took up a higher orbit than last time, almost 90 KM, and deployed the first lander. Lander #1 went down with a pilot and good fuel for the landing.  I freely admit to using mechjeb (sophisticated autopilot) for most of the advanced maneuvers in this mission.

You can see the solar panels deployed here, as well as the landing flag. The whole thing was smoothly run, which is a major relief after the last mission here. Total time for the first lander on the surface was just under an hour.

Lander two put down in the heart of one of the largest craters. The scenery wasn't too different, but from  an orbit standpoint the geology would (in theory) have been markedly different.I took soil samples, recorded observations and then returned each Kerbil to their lander.
Unmanned orbital surveyor drone 
A good view of the drone with its solar panels deployed. 
The second part of the mission was high altitude mapping mapping. The Drones I built were meant to be able to maneuver as close to Mun as possible without needing life support, or putting a Kerbal in danger. I set one drone up on a 110 KM orbit, and the other at an extremely low 20 KM orbit. While the game doesn't actually record mapping data, I stand by my assertion that even with 1960 technology, the date these two would have brought back would have been excellent.

Docking lander #2
  It took close to an hour of work to get all four separate elements back to the Explorer, each one had to be docked individually, of course. but the process was worth it, of course. When I was done, I made sure to drain all the remaining fuel into the main tanks, and to turn off Lander or drone RCS systems. After last time, I wasn't in the mood to take any chances with fuel. 

Parting shot as I depart Mun, Kerbin and the Sun in the distance. 

The return trip to Kerbin took less then a day and a half (Thank God for time acceleration). With the engines, it was easy and smooth sailing to move into a high earth orbit. 

Return to home orbit. 

The "Werm" and the "Explorer" about to"Kiss." 
The final stage of the mission was to get my crew of Back down to the planet. I short of cheated, the capsules used in the game only sit three, but the Space-X Dragon currently in use will sit 7 once the manned  "DragonRider "unit is authorized for flight. So... I used the parts I had and made a ship I call the "werm" (pronounced "verm" in reference to the German term for "dragon").   I originally loaded the crew with the same ship over a week before, so I kept it in orbit rather than have to built and fly a second one. 

The great beast in its well earned slumber.
Not the most "convention" configuration, but... it worked for me. 

With the crew aboard, I closed down the Explorer's systems and lowered the solar arrays for its period of "sleep" before the next mission.

The Werm returns from orbit as one unit, and separates just before the chutes open. As luck would have it, the process worked, and all five passengers walked away from the landing without a scratch.

Now that's how to end a mission!

And just for reference,
these images of the Explorer I (bottom) and Explorer II (top) for direct comparison.
(note for scale, the command pod on the nose is the same part in each ship)