# CrazyJebGuy

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1. ## Discussion of Non-relativistic Interstellar Space-Flight at Light-Speed

"Non-relativistic" as in this hypothetical assumes no relativistic effects. (e.g. relativity is wrong, or it's a fictional setting without it.) It's just Newtonian physics here. So, what challenges are there in going faster than light, even with relativity's absolute ligh-speed limit removed? Want to hear thoughts/problems with this. Here's the one I thought of: HEAT PRODUCTION Space, even interstellar space, still has stuff. One hydrogen atom per cubic centimetre is the usual figure I've heard. But when you're going at light speed, that creates issues with cooling. For one square meter of cross-sectional area facing forward, it will get hit by v*106 atoms per second. In weight, 1.7e-18 grams of matter per second. The kinetic energy of stuff hitting it will be 0.5mv2, and putting the mass/s in, we get a kinetic energy absorption = 8.5e-19v3. Assuming velocity is c = 3x108, energy per second is (27*8.5)*105 = 2.3x107 watts. Presumably, most of this is going into heat, so let's assume the wall on this spacecraft is 5 inches of steel. Steel is about 8 tonnes/m^3, so this square metre space-ship front weighs near enough 1000kg. Steel melts at 1510c, and let's assume it's 0c. How long could we travel at light-speed before it reaches 1000c? Specific heat capacity of 452 J/kg, so 452,000 J to heat the ton one degree, and 4.52x108 to heat it to 1000 degrees. We have 2.3x10^7 watts of heat, so it will last about 20 seconds. That's a bit of a problem if we want to go interstellar, or even to Mars. The sun is 8 minutes away, so anything further than the moon is more or less out of the picture. I want some input on these next things: what effect would angling the plate have? Currently we've assumed 100% of the collisions' energy goes into heat. But if we angle the plate, wouldn't the incoming atoms bounce off, potentially sparing a lot of the heat? I don't know how to calculate this, but what fraction of heating might be avoided if the plate were angled away by 60, 70 or 80 degrees? Also, what cooling might there be? We're assuming really advanced propulsion, but for fun, how much heat can KSP tech radiate? The wiki says the radiator panel (large) can dissipate a max of 3.64 MW. Since 1c generates 23 MW, we would need 6.4 for every square metre facing frontally, just for 1c. That sounds pretty managable, though I don't have KSP installed right now and I can't check how big the panels are. Still, it will place a heavy restriction on any potential spaceship's design, because it will need a lot of sideways/rear surface area per frontal surface area, and it means the spaceship must face the direction of travel. What if we wanted to go faster than 1c? The formula I got for kinetic energy absorption goes up with v cubed, so 2c has 8x the heat, 4c has 64 times, and we're still looking at over a year to get to Alpha Centauri. We'd need about 420 large radiators for each frontal square metre, and that's beginning to get absurd. Aside from other issues/thoughts, any solutions to the heating problem at over about 2-3c?
2. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

I was flying manually, and without fussing over getting the absolute best performance out of the plane at any cost, because we needed a margin for error, and because it rewards stable/easy to fly designs, and it saves a lot of time. Even so, a few planes are pigs to get up and flying right (particularly supersonics) and took ages. Generally my not hyper-careful methods of flying meant that when I submitted a plane the range I advertised was usually slightly less than what it would be officially. Not by much, but I noticed it. Most annoying bit would be testing at multiple altitudes or engine modes or something.
3. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

The categories became a bit of a blur in the last one, but other than adding a few tiers of jumbo (because a 152 seater should not at all be put in the same category as some of the hulking behemoths that we posted up before) I don't really see the point in the ultra-long haulers. They've always found their places in with the other planes, just with a bonus of a 6 or 8000 km range. Hoppers, I don't think anybody actually submitted any, and they were pretty niche to begin with. Maybe they get one category, maybe they get lumped in with 'other'. I don't want to touch helicopters myself. I also think jumbos are pretty good, (and designing stupidly big ones was a lot of fun) so I won't remove them at all. Supersonics should have their own categories, and maybe not any with under 60 passengers, ( + hard range requirements, maybe 3400km minimum?) because they don't make sense for short trips. I think they should cost more to maintain and design than subsonic planes of similar sizes. I think seaplanes should be kept as a small category to themselves, (though any plane can be a seaplane) running just 'area' routes, maybe not going from city to city (there probably won't be many unless I can get a good spreadsheet going, because each city makes it more complicated than the one before. I'm worried that it's just going to be too complex, but spreadsheets might save me.) but servicing just an area, going from small town to small town, landing in lakes and rivers and fields and wherever else is practical.
4. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

It's already there, kind of. Each company starts with a set amount of money (10 million, it doesn't matter what exactly) and designing a plane costs money, and bigger, more complicated planes will cost more. (Each type of plane will have a base cost, say 400k for a turboprop, plus maybe 12k per passenger and 5k per part count, so a typical turbo prop might be 800k-ish to design, a Smallie might be 1.1 mill and it goes up as the planes get bigger)
5. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

However, I do want a rule where a reviewer can say that the RnD cost nothing, because clearly none was done. I want this so that you can invoke in on the designs that are so bad that they're great fun to review. There's been a few bombshells of planes like that, and I like them. (Though I want it to be rare)
6. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

10 is reasonable. Perhaps a little high, but reasonable. Remember that's per person, so it could still multiply out to large numbers.
7. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

That's where another bit of my business sort of idea comes in. It will cost your simulated company money to design a plane, (though you can get more money if people buy it) which will keep it down a bit. On top of that, maybe a hard limit that you can have no more than 6 unreviewed planes submitted at any one time or something.
8. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

It doesn't have to be the same people, but even if one guy did run an airline then you've got KEA already, and then if you just design aircraft you'll be able to see what they're doing.
9. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

It's late at night for me, but I'll respond to this now: (but the rest maybe tomorrow) perhaps it could be different threads (but closely related, e.g. one has all the submissions of aircraft, one has reviews, one has bla and bla... all linked) or just one. But I know it would be more complex, but assuming I can manage the complexity of all the behind the scenes stuff, it can still be simple for others. If you want to only design aircraft, you can do exactly that. Others are free to go and business their own companies as they would like. (Maybe you can design something and 'sell'/license it to someone else who handles whatever businessy things I add in) If there are problems, we can work out the details later. But I'm just curious what people think of the overall idea.

11. ## Kerbal Express Airlines - Regional Jet Challenge Discussion Thread [Thread Opened]

Sorry about the inconsistency, I'll have to get on with updating the leader-board, although it's very long already. I joined this thing about a year 5 months or something ago, my interest is simply fading. Aside from this I haven't been very motivated to play KSP since 0.90.
12. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

Super-jumbos are hard, and I haven't seen anybody design one which does it well. The Brittanic I made comes close, but I'm not satisfied with it because it's a lot slower than I'd like. Landing gear is fairly simple though, you can't go too wrong with long gear up front, and just behind the CoM; just be careful to make it so it won't tailstrike and break things. (Which can be done by sticking another smaller landing gear or a steel beam at the back to protect the tail.)
13. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

Gawain Aeroplane Industries Presents: The GAI Britannic With 912 passengers it's a modified Sky Titanic. We fixed the problems it has (such as rapid unplanned disintegration) and improved the plane. The main changes involve a complete rework of the structure and supports, new landing gear and reduced wing-span. It was found that the wingspan in the Titanic was too long, and twisting the fuselages inward in turns. Previously our engineers had no idea what auto-strut was, (the Skots Squirrel is I think the largest plane to not use autostrut) but this new technology has meant the airframe now can be stronger, lighter and cheaper. The elevators were reduced in size and the canards removed, along with the experimental airbrakes. (Elevons which extended with the brake AG - doesn't work for a plane this big) There are also a few additional cabins near the rear, bringing the passenger count to 912. Partcount has been reduced from 325 to only 192. We changed the engines too. Takeoff distance is very short, just pitch up once you get to 40m/s and the plane will lift off at about 60, before getting to the astronaut complex. The afterburners are recommended for this. Price: \$299,503,000 Passengers: 912 Part count: 192, 10 engines. Speed: 271m/s @ 4000m dry, 580 m/s wet. Range: ~5100km dry, ~2000 wet It's recommended to fly between 400 and 5000m. The pitch is very powerful and the plane can enter a spin, which is done more easily at high speed/altitude. The engine gimbal (AG2) is recommended to be disabled when going over 180m/s. Afterburners (AG1) recommended for climbing and takeoff. If a spin is entered the rear parachutes normally used for braking can be instead used to get the plane back under control. At high speed we advise turning very slowly and cautiously, even though the parachutes can bring the plane out of a spin. If they are used in flight, the plane can go to about 580m/s, this makes it the largest supersonic jumbo. (Possibly, I don't know if it has more passengers than @Andetch's Mr Tiddles) It can also water ditch safely, and take-off again. (For water takeoff, frontal flaps (AG3) are recommended.) Since it can takeoff from water, we're also entering it as a flying ship, and we put rope attachment points on the plane so it can be operated out of harbours and moor at docks like a proper ship, there are even small underwater water-jets to help with docking. Get your here: https://kerbalx.com/BristolBrick/GAI-Brittanic
14. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot Continued)

I did build one, the Skots Economy. None were bought, which I think is a bit unfair considering that it was actually good at carrying cargo. Now since everyone remembers the famous success of the Sky Titanic (Review here. Basically if you turn or land it explodes, it looks awesome.) we decided to improve on the design, and change the name because we think it may have been jinxed. I'm not going to submit it yet, I want to make the air-frame more stable at high altitude and speeds. (It tends to start suddenly backflipping and then fall feet first into the sea) I have fixed the tendency to disintegrate, by shortening the wings. Which also made it faster and with the new landing gear it takes off at about 60m/s anyway, so the longer wings were completely pointless. I also replaced the engines, it is about 60m/s faster now.
15. ## Kerbal Express Airlines - Regional Jet Challenge (Reboot)

Wrong thread, but yes. It's here. https://kerbalx.com/BristolBrick/GAI-Tupolov
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