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  1. I built a small plane powered by electric ducted fans and a few RTGs, which is capable of infinite flight. I was flying it on long flights around Kerbin where I set MechJeb to cruise at 4000 m altitude. I noticed something interesting, which is that the maximum cruise speed decreases as latitude increases. At the equator, it could cruise at 280 m/s but this speed gradually drops to 250 m/s at 60° latitude, which is a difference of more than 10%. As I flew back towards the equator, it gradually increased back up to 280 m/s. Even more interestingly, the blade pitch at which this maximum cruise speed occurs decreases from 49° at the equator to 46° at 60° latitude. The electric motors are always at constant (maximum) RPM and the mass of the aircraft is strictly constant as no fuel is involved at all. This is not an issue of bad controls as the plane is just not physically capable of cruising at 280 m/s at 60° latitude. I think the reason has to do with the temperature, pressure and density of air varying with latitude. Can anyone explain?
  2. This is the new thread. The original thread can be found here. Advanced Jet Engine About Advanced Jet Engine gives jets, propellers, and rotors realistic performance in KSP. NathanKell's valiant efforts have made stock performance much more reasonable in recent versions of KSP, but it's still a very long way from realistic. AJE calculates performance for air-breathing engines based on real thermodynamics. Features Real-world jet engines AJE uses thermodynamic equations to calculate jet engine performance in flight. Real throttle Throttle is linked to fuel consumption instead of thrust. Afterburners, if installed on the engine, is turned on when throttle > 66% and off when throttle <= 66% Overheat. Like in real world, not all engines can tolerate the heat from air compression of hypersonic flight. This is affected by both mach number and throttle Inlet. Each engine requires a minimum inlet area (see right click menu in editor). Make sure you have enough inlet till you see "Inlet Area:100%" in flight. Each inlet has a TPR(total recovery pressure) that is dependent on Mach number and angle of attack. Avoid TPR loss by facing the inlet to the freestream. Download Download Latest Version from Github Also available on CKAN Troubleshooting If you are experiencing an issue, please read this topic, if you have not already, on how to get proper support. Incomplete support requests will not be processed. Most importantly, include logs. Source On Github Requirements Each release of AJE is intended to be run with a particular version of KSP. Please only use that version. If you have an earlier version of KSP AJE requires these mods to work. It will not function if they are missing or not installed properly. ModuleManager SolverEngines AJE does not explicitly depend on Ferram Aerospace Research but has not been tested without it, and you will probably think that your engines are very underpowered in stock aero. Recommendations Ferram Aerospace Research, as above. AJE might work without it, but it's not tested and you will probably not have much fun Real Fuels - if you're going to have realistic jet engines, why not use them with real world fuels? Mod Support AJE has configs to work with the following mods' engines: B9 Aerospace SXT (Lack's Stock Extension) Bahamuto Dynamics KAX (Kerbal Aircraft Expansion) AJE has configs for these mods, but the configs may not be up to date: Mark IV Spaceplane System AJE has configs for these mods, but the mods themselves haven't been updated in a while: Taverio's Pizza and Aerospace D12 Aerotech Retro Future Changelog License AJE is licensed under the GNU Lesser General Public License Version 2.0 AJE incorporates portions of NASA EngineSim; used according to NASA's license thereof with due credit. AJE incorporates portions of JSBSim by Jon S. Berndt, used in accordance with the LGPLv2 Authors @camlost @NathanKell @ferram4 @blowfish And all others who have submitted fixes and enhancements
  3. OK I am in the middle of making a large electric submarine on the PS4 and thanks to some very helpful advice I've managed to get it moving at a blitzing 1.5 m/s utilizing the heavy rotors and elevon 4 I think? The one with pointy ends on both sides in a kind of slanted square shape (if that helps at all). The sub itself is easy but during my now 10 to 12 hours worth of experimentations some of the parts for the propeller have been doing some very wierd things like flipping mirrored and unmirrored constantly while underway which kills off all thrust. Experienced Kerbal lords and ladies of the sea I humbly ask what parts have worked for you (other than jets) and how do you fashion your water whipping propellers to dominate the wet parts of Kerbin?
  4. Trying to work on Eve SSTO, realized that it's impossible. Although, in this process I got a single stage (stock) propeller plane with rockets equipped capable of orbit. It ascends to the edge of the stratosphere only with propellers, and get into orbit with rockets. Album https://imgur.com/a/Ux6qS will appear when post is submitted So propeller plane can get to stable orbit, if enough rocket engines and fuel are provided. Then, a new question arose. How far can a propeller plane go? Rules: 1. No cheating, No Alt+F12 cheats in flight. (Visible bits are allowed) + No mods with gameplay effects. (Again, visible mods are allowed) 2. Only rocket engines and stock propellers are allowed on the entire flight. No airbreathers, no infiniglides, no gyroscope drive, etc. 3. The plane should be able to take off and fly around fully-fueled with propeller-only. 4. Propellers should be able to be re-docked to the craft, to ensure the completeness of the craft on orbit after physics load. 5. It shouldn't take over an hour for a craft to get to orbit. 6. At least a kerbal should be on board. Score is the dv left on orbit. The destination of the plane can be noted on the leaderboard. Leaderboard: + All rocket engines allowed 1. @Reusables 3m/s 2. @Reusables 0m/s + Propeller-Nerv SSTO 1. @Reusables 3m/s + Propeller-Ion SSTO 1. + Propeller Passenger Plane (contains Mk3 Passenger Module) 1.
  5. Note: At very low torque, this mod makes the rotors consume extremely low fuel, making them rather overpowered for small planes such as the one pictured. Balancing is in progress. The Kerbal Space Center made a biplane using the R121 turboshaft engine, and it ran out of gas before it could fly a km away from the space center. After Jeb safely whipped that baron onto the mysterious green substance that makes the scientists yell at him for not cleaning his boots, the incident report team at R&D realized that it consumed fuel 6.25 times AFP (At Full Power) faster than the small jet engine AFP! The kerbal engineers contacted C7 Aerospace Division only to receive automated replies spouting nonsense about a warranty. Fortunately, Jeb owns his own junkyard and with a bit of duct tape and some spare parts the Kerbopower 108 was good as new and ready to circumnavigate the world!* Of course it was only after all of this that C7 Aerospace Division finally bent to the countless lawsuits of failed classic airplane designs to revisit their horribly designed turboshaft lineup. As much as their management hated them, however, the recalls saw resounding success. Spacedock! Github! [Source] Find it on CKAN! Soon! Hopefully! *Circumnavigation requires frequent stops at intermediate airports. The Kerbopower 108 has a powered flight time of 25 minutes with rebuilt engine on a full tank with cruise speed of 270 km/h or 75 m/s. Range may be increased by flying at lower power. For increased fuel capacity, consider purchasing the Kerbopower 105 or Kerbopower DT-1 supplementary fuel tank (sold seperately) Graphs for smarty pants: Contains MIT License. If you have a better idea for what license to use, feel free to leave a comment. I wasn't sure which one to use because this mod is a very tiny patch to make the LF consuming rotors actually useable in career mode, so I just used the same one as another tiny modlet. Though that one was a plugin, so I may not have been correct in doing so.
  6. Compact, lightweight propeller plane, with near infinite range. Possible recharge while flying, control via relay network or kerbal. Able to survive signal loss inflight until next relay satellite in reach, due to its low minimal speed. Built for eve. Up to 10km, 128m/s, recharge inflight, 37 parts, 948 kg. Breaking Grounds mandatory, no mods Controls: 1: enable thrust / main thrust: rotor speed Download: https://kerbalx.com/Tahib/Eve-Flieger-bbq
  7. I don't know why, there's something intriguing about an all-wing craft. So, here's the Boomerang. A (more or less, it's got a fuselage) flying wing. Easy to fly, and long ranged, it carries five kerbals- four passengers and a pilot. check it out here: https://kerbalx.com/lucho/Boomerang
  8. This is a simple question, but I know very little about how these things work. My question is how do propellers throttle? I can't imagine they use blade pitch like in ksp. I have seen many things propeller planes and most don't appear to have propellers that can change pitch. Also, in rl I have flown drones that can definitely throttle and definitely don't have pitching propellers. This is also how planes behave in simulators like real flight 9. My best guess as to why this is not true is that ksp's physics engine cannot simulate rpm's high enough for propellers to throttle by changing rpm like my drone appears to.
  9. I would like to be able to hear the signature chopping sound from the helicopter blades. It would really add to the immersion, it feels kind of weird to have a massive chopper flying around that makes no sound at all. Bonus points if the chopping sound becomes quitter on Duna and disappears in a vacuum. Here's a concrete list of additions I would like: Blades make "chop" sound effect that depends on the speed and atmospheric pressure Electrical engines have a slight electric hum, bigger engines could hum louder I was actually really surprised when I discovered this wasn't in the game already Thanks for reading
  10. Spear of HorusDisclaimer(needs breaking grounds for robotic parts)(to match graphics shown in screenshots make sure you have downloaded stock only version or restock) *not restock+ (this is optional not needed this is fully stock)Controls:USE I and K to tilt Vtol wings Forward and BackDual VTOL technology.|( KAL-1000 mapped to Main Throttle: Control Fan Pitch/Deploy and Speed )||( AG1: Toggle 8 Juno Engines )|Throttle|( Dual Juno (AG2: Toggle Engine )||( Panther (AG3: Toggle Engine )||( Panther (AG4: Switch Mode )|Decouple|( AG5: Decouple Node ) Decouples from node for the first time )||( AG6: Undock Node *available after using AG4 at least once to redeploy after successful redock )|Part of InterstellerKev’s Phaethon Dynamics series:Short Story -The head of a falcon and the body of a mere man was really the sky god once known as Horus the deity of past Kerbal History. Once said to fly all day and night.They said he held a spear called The Spear of Horus. Reading ancient hieroglyphs contained some old Blueprint for his Spear of Horus! It turns out it is a Flying Vehicle of some kind?!Ground breaking theories are now shattered. We have to rewrite history. Questions like “did aliens come down and help build the monuments that still stand today are now more concrete. KerbalX: https://kerbalx.com/InterstellarKev/Spear-of-HorusSteam: https://steamcommunity.com/sharedfiles/filedetails/?id=1983151486
  11. First post here so sorry if I am posting this in the wrong place When ever I try and build single engine propeller aircraft it rolls to what ever direction the engine is spinning and I also notice that they tend to slowly pitch down on there own. My question is that is there a way to mitigate these issues?
  12. This post is to share some tips at improving the efficiency of turboshaft engines, driving propeller blades (airplanes) or rotor blades (helicopters). The concepts should apply equally to electric rotors driving propellers or heli-blades. I'm using 1.7.3, the electric rotors, turboshaft engines, and propeller/heli blades are new to stock KSP, so in later versions some of this info might become outdated. It's easy to focus on either the Turboshaft Engine, or the Prop/Heli blades when troubleshooting 'why doesn't my vessel work'. The reality is you need to look at both elements to make a functioning prop-airplane or helicopter. The engine produces torque, which spins a shaft. This is important, torque produces zero thrust. Add all the torque you want, it will not produce any thrust- until it is coupled to a lifting device, such as a propeller blade or heli blade. On the other hand, the prop/heli blade also produces no thrust unless it is moving. You can angle the blades any way you want, they will produce no thrust unless they are moving. The movement is provided by the Turboshaft Engine (or electric rotor). As of 1.7.3, the stock engines can rotate at a maximum rate of 460 rpm, which is evidently a Unity limitation. Adding torque will increase rotational speed (rpm) up to that limit of 460 rpm. What happens if you are already at 460 rpm, and increase torque? That's an important question. What happens (in 1.7.3) is you increase the Fuel Flow (or EC draw), but do not get any increase in rpm. Beyond 460 rpm, adding torque is simply wasting fuel. In the following examples, we're going to experiment with turboshaft engines. There are two variables we are going to adjust, and unfortunately they are on two different parts. One is the Torque of the Turboshaft Engine, the other is the Authority Limiter of the prop/heli blades. To make things easy, I like to assign these values to action groups. I assign Engine Torque to the Main Throttle, and the Blade Authority Limiter I assign to Translate Forward/Back (usually 'H' and 'N'). Okay, lets get started. Here's a turboshaft engine we're going to play with. It's in the 'propeller' configuration, but the idea is the same for helicopters. Ok, we have an engine built on a stand, let's play with it to see how Torque, Blade Authority, RPM, Fuel Flow, and Thrust are related. In the next spoiler window, I'll play with Torque and Blade Authority Limit, to see what happens to rpm and Fuel Flow. Keep in mind that Thrust is only dependent on rpm and blade angle. If my rpm and blade angle stay constant, but my Fuel Flow increases, I have not increased my thrust. I'm just wasting fuel at that point. So, one goal is to find the minimum Fuel Flow which will maintain a specific rpm at a specific blade angle. Here goes. In the next spoiler window, I'll demonstrate an actual aircraft, making adjustments to torque (and Prop Authority) to reduce fuel burn. Ideally I'd use a single-engine airplane to keep things simple. However, counter-acting the torque effects of a single-engine are difficult to design for, and fly efficiently. It's easier to just make a plane with two counter-rotating engines and propellers. Then, it flies quite easily just like a jet, with no nasty torque effects. The takeaway here is that to get the most out of the turboshaft engines and propeller or helicopter blades, you need to look at more than just the engine or just the blades. Both elements need to be adjusted for optimum performance. Ideally, you need to be able to adjust both Torque and Blade Authority Limit in flight, to adjust for varying conditions. Regarding efficiency, the big takeaway is that adding Torque beyond what is required to maintain rpm is just wasting fuel, and lots of it. As of 1.7.3, I believe the concept is the same for electric rotors driving propellers or heli blades- adding torque beyond what is required is only wasting EC.
  13. I'm creating a V-22 Osprey replica with the new robotic parts (incredibly original idea, I know). I am using the largest helicopter blades and the R7000 turboshaft engine. The vehicle lifts off fine, albeit with some help from vernor engines, but the second I enter it into "plane" mode the engines are massively too weak to propel it, capping at about 35m/s. The vehicle weighs 66,5 tonnes. Is there any way of improving the thrust/weight ratio without adding more rotor/jet engines? Why is it that they have enough power to lift the whole thing off the ground, but not to propel it? Since I'm new here and couldn't figure out how to insert images into my post, here's an imgur link: https://imgur.com/a/msRQ73z
  14. I have seen one other suggestion topic about this before and it was abruptly closed and not re-opened again. Really my question is why don't we have propellers yet and what might the chances of us getting them be? (And yes, I'm aware of mods, but I happen to like playing games stock)
  15. Disclaimer: English isn't my native language, I do my best. Clay Parts; no it's not about clay but its malleability. My idea is a completely revamp part system where your parts adapt to the shape, size, fonctionnality and visual you want. Less parts (even with a lot of mods), just highly configurable ones and configurations. ClayAddons will be a serie of standalone mod that interact with each other alot. This post is about discussing and defining the theoretical rules between each part and functionality. Ex: relation between size and thrust of an engine. As ClayAddons will contain alot of stuff we will go step by step. First one engine! How engine are handle by the mod (ClayEngine). Engines includes everything that allow movement, motion or implied motion ex electric generator. In fact the mod include no engine, but engine module or component (you can have multiple engine module in one part and module on a part can interact with module on other parts). Ex1: the propeller is a module, piston engine is another one. Ex2: combustion chamber is a module, tuyere (nozzle) is another one. Each module have a whole range of option ex: size, number of piston(piston engine), number of blades(propeller). Each module can have one or multiple virtual and physical nodes. Module node are port for linking modules with each other like electric plug. Nodes can be connected when module are placed inline or with various cable: electric cable, fuel line, shaft, cable(rope or metal cable), track(for wheel), chain, belt, pipes(yes pipes for air, water and ??????. So air intake need to be connected to engine using pipes.) Virtual nodes are for internal use only. Physical nodes will lead to the outside of the part of his module if not linked to anything else ex: exhaust, air intake. For physic ease all those internal logic will be simplified at vessel load. I need your help to define module their nodes and options. +Mass etc let focus even more---> Propeller engine + Piston engine Propeller component: core (nose cone): size, mass, drag, internals blades: number, size, drag, design, thrust ressource: torque, rotation, air, thrust, data Piston engine component: piston: number, size, configuration, mass, power ressource: electricity, gas(oxygen), gas(CO2), liquid fuel, torque, rotation, heat, data Gearbox: type(planetary, ....), mass, size ressource: torque, rotation Shaft: mass, size ressource: torque, rotation Those four element interact by torque and rotation For later
  16. Is there a way to make functioning, preferably electric, propeller engines in the stock game, without having them be a separate craft? I know of one youtuber who built a cool fan boat, but his design required stage separating the propeller assembly and controlling it as a separate craft. I'm looking for a way to propel an amphibious base on Eve's bodies of explodium, so jet engines are out of the question, and rockets would be extremely inefficient.
  17. Dunasoar is a twin engine airplane designed for Duna exploration. It can transport 5 kerbals, or it can be easily modified to run science gathering missions. Max speed is about 175 m/s. Plane uses modified version of my fairing prop engines powered by fuel cells, but if you don't like using the fuel cells you can replace them with RTG's. These engines are little bit bulkier than my usual fairing prop engines. But the best part about them is that I've finally managed to create a reliable mechanism, which uses the claw inside the engine nacelle, to re-dock the propeller to the plane. That way the plane can be used multiple times, and you don't have to worry about the engines falling apart if you leave physics range. Finally you can make a plane which you can use to explore all biomes on Duna or Eve. As usual when flying a plane on Duna trickiest parts are takeoff and landing so choose your landing area carefully. Here is a link to the craft file and instructions on how to fly plane.
  18. Do you guys think that propeller engines should be added to KSP? Propellers would serve as precursors to Jet engines in Career mode. They would have less thrust, but would drain fuel slower. They would also be cheaper than other jet engines.
  19. I'm mostly asking for help in this thread. I'm currently trying to develop vehicles I can deploy permanently in the field to support a career mode colonization effort. This means I need to set up mining facilities, SSTOs, and small towns on every planet. Perhaps the most difficult planet to set up such a colony with reusable technologies on is Eve. Thanks to its dense atmosphere, simply using aircraft to fly at faster than driving speeds between bases is a compelling option. However, jet engines obviously don't work inside Eve's atmosphere. So, I have to resort to stock electric propellers (unless I want gas guzzling rocket planes that are mostly fuel, and need to land and refuel multiple times in one trip). My difficulty is prototyping a stock electric propeller with the specifications I want. I wanted to make one out of .625 meter parts, to push the size and mass limits of stock propellers (and then scale up from there for larger planes). This means using .625 reaction wheels, and possibly using .625 meter decouplers in some manner as the bearings. Next, the prop needs to be able to redock to the mothership, since propellers tend to break easily whenever the game loads or unloads a vehicle with a propeller. And finally, the propeller needs to be a sub-assembly with a docking port, so that I can change out a broken engine in the field if I need to. No sense in condemning an aircraft I went through the trouble of getting to Eve if all that broke is the propeller. Anyway, I haven't had too much luck, a whole lot of friction between parts, and the prop breaking free of the different kinds of bearings I've designed. So I thought I'd turn to the KSP community for tips or tricks on designing props that aren't just for show, but are actually useful and utilitarian. The ability to redock is probably the part I care most about. I also have the making history pack, so I have those parts to draw from for making props as well. The structural tubes might be useful for 1.25 meter props and up.
  20. After learning how to make propellers in stock KSP, I wondered if it was possible to make a solar-powered aircraft, like Solar Impulse or the NASA Helios. The problem is, all the propeller engine designs I've seen require the engine to be physically separate from the aircraft, preventing electricity from wing-mounted solar panels from reaching it. Is it possible to make a propeller engine that isn't physically separated from the aircraft, or somehow "beam" electricity into the engine? If not, are there any easy code fixes that can allow either of those things?
  21. Typically, as the thrust produced depends on the propeller used and the airspeed, propeller engine performance IRL is measured in horsepower or kilowatts. As stock propellers require a constant amount of electricity to run, we can find their in-game power consumption in units per second easily—in fact, by just looking at the Resource bars. However, there are 2 potential ways to convert this into real units: A solar panel of a certain area pointed ideally at Kerbol from Kerbin will produce a certain amount of charge per second. An in-game power-per-unit-area figure can be calculated from that. Compare that with Earth's 1361 W/m3 ideal power-per-unit-area figure. This will of course depend on the efficiency of the solar panels used, but assumptions can be made. More reliably, the Realism Overhaul mod suite has a conversion factor from units of electric charge to Watts in case a part specifies its power consumption that way. So, it should be possible to measure the power output of stock propeller engine. It should also be possible, though difficult, to measure the mechanical efficiency of the engine by taking into account the rotary's* moment of inertia, angular acceleration, and cruise angular velocity. Has anyone ever thought of this before? Regardless, if you have made a stock propeller aircraft, please post the power output of the planes and engines you've made, as well as preferably their masses. Posting mechanical efficiency would be really awesome. *Most KSP stock props are technically rotary engines.
  22. Introducing the LF (Light Flyer) 1, 'Bear'. It has space for six Kerbals, can fly for around 3 hours, has airbrakes and parachutes, can be fitted with landing gear or floats, and has a top speed of 281m/s, and only costs 15,000!
  23. To start off, I would like to credit MajorJim as the original creator of the bearing. Klond and Azimech for developing the modification that uses RCS Balls. Big thanks again to Azimech for showing ways of optimizing the bearing to make it even better and even more reliable. ________________________________________________________________________________________________________________________________________________________________________ With that out the way, Here's the actual post. I apologize for not existing for so long, there's no reason for it, I was just too lazy to post again. I've made many planes (mostly with spinny propeller things) so today, the one I've picked out for today is... The DC-3 Dakota (AKA, the C-47 Skytrain) The DC-3 was an airliner developed in the 1930s and was developed from the earlier DC-2. The DC-3 turned out to be one of the most successful aircraft in the world. What makes it unique compared to most aircraft designed before WWII, the DC-3 is still in (limited) use. During WWII, the DC-3 was converted into a military transport called the C-47. It was considered one of the best transports during the war. The replica I've created is down below. _________________________________________________________________________________________________________________________________________________________________________ _________________________________________________________________________________________________________________________________________________________________________ Instructions and Download 1: As soon as the crafts spawns in, turn on the brake. 2: Decouple the propellers and turn on SAS afterward. 3: Switch to one of the propellers using the [ ] keys. 4: If the propeller selected is on the left, hold down ALT and E until the roll indicator in the bottom left has reached completely to the right. 5: If the propeller selected is on the right, hold down ALT and Q until the roll indicator in the bottom left has reached completely to the left. 6: Switch back to the main craft, and turn off the brakes as soon as the propellers are both spinning 7: If done correctly, the plane should start to move. On takeoff, the plane should take off on it's own if left alone with SAS on. 8: Have a nice flight. Try avoiding excess manouevers. Download (HERE) _________________________________________________________________________________________________________________________________________________________________________ Thank you for reading! Sorry I've been away for a while. However, as a sorry gift for keeping you guys waiting, I have a bonus craft down below. Enjoy!
  24. I have a working stock propeller (following Squiddy's tutorial). It works properly and will fly, but when I switch from the propeller to the plane, the propeller's trim (alt+e) lock gets reset and it slows down. I have to keep switching back from the plane to the propeller to spin it up again. Does anyone know how to keep the propeller spinning when I switch vessels (keep trim lock on)? Sorry for the possibly confusing description of the problem, please ask if I need to clarify something.
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