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OffsetIsMyName

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  1. Wow, great job! And it's unpowered when in flight haha so that indeed is possible! Seems then from your experiments it happens with control surfaces just aswell. For some reason I had differing results, though I spent a whole of 16 seconds trying that out and then went back to checking how the wing parts behave.
  2. That sounds very familiar! Not sure if you tried, but did the propellers work just as fine when spinning at the "wrong" direction? Because if you arrange the wing parts on a prop, be it electric or jet propelled, pointing vertical and without any angle of attack, but tilt them slightly so that the tips point outward (like in the screenshots above), it doesn't matter which way you spin the prop it will generate exactly the same lift anyway. Certainly a bug, but for what I tested it was hard (or for me impossible so far) to get into control. With some designs I could go way up (20km) around 150-200m/s all the way, but at some altitude the spaghettification got so strong that after separating the rotor parts to leave behind a lightweight rocket for orbit the whole craft was mangled up so bad it was useless. But no way a small reaction wheel could generate that lift with regularly angled parts. I have a feeling this might have an effect on many prop designs as during load they flex and the angles are no longer what they were in the editor. They seem to move both laterally, vertically and rotate under load. If I use rigid attachment then I feel the prop behaves more realistic due to no centrifugal expanding or any other that stuff. Making the blades offset more just slows it down and the total lift remains more or less the same. (Edit: oh wait, would that suggest that with expanding blades the drag is calculated with the original offset? props gain so much more power when they expand than when they don't) But.. Add more blades and suddenly the rad/s is still the same but lift increases linearly with blade count.. That's not very realistic. The design that I got the most out of was the blades with almost zero angle of attack, but tips pointing upward, maybe 30deg from vertical. The small angle of attack prevented it exceeding the 50rad/s limit as much as it does without anything producing drag. It still did, but without any angle of attack and thus almost zero drag I noticed speeds of 700m/s when the physics engine got really mad. A split second later kaboom Edit2: forgot to mention, that due to the direction of the lift vectors and almost zero drag, it means that after reaching a certain rotation speed you can no longer stop the rotation. The lift itself tries to accelerate the rotation even more. I guess a completely unpowered flying contraption is possible if something external just provides an initial kick to the rotor.
  3. I think I found the reason why many of my test craft are getting major compounding feedback loops with aero parts (wings only, control surfaces seem to behave differently). I was trying to make a lowest possible weight craft that can reach LKO and during that I fiddled with it's blade angles which were made from the smallest wing parts available. I found that turning the wing part upwards and reducing the actual angle of attack increased the thrust. Then I tried putting them completely vertical, with zero angle of attack, spun it up and shortly there was huge lift vectors going horizontally (no actual lift in this case then) and soon the rad/s went over 50rad/s and craft got spaghettied & exploded. The blue lift vectors before the explosion were as long as you can possibly see. Thinking from where the vectors were pointing at it seemed logical to slightly tilt the blades, still no angle of attack, so that the vectors would point more upward. 15 deg tilt and the craft launched 150m/s in the air before exploding. Mass was around 400kg with one of the smallest reaction wheels doing the job. Works just the same with turboprops though. So in a nutshell, you get lift while getting almost zero drag. Anything can spin zero angle of attack wing parts pretty easily. My reasoning behind this is that KSP calculates the current physics frame lift values by using the current velocity of the part, but the orientation of said part from the previous frame. Or something in between assuming it tries to semi-properly integrate the movement that "happened" during two physics steps. But then, I think drag values are calculated with the current velocity and the current orientation so that while lift is calculated with incorrect angle of attack values, drag is calculated, perhaps incorrectly too, but at least closer to the thruth.
  4. I was reading the topic for older posts when I bumped into your discussion about the claw. I am not sure if you figured it out as I have not read everything, but a fuel duct to the claw allows for one way transfer. Before decoupling After decouping, activating engine and throttle up After freeing the pivot
  5. Would seem the axle parts are exposed to air if the nosecone is detached too so it seems the fairing is pretty much useless how I used it. Wanted to have the nosecone spinning so I could leave the blades partly inside of it, mostly for the looks of not needing to offset so much and was easier to keep the elevons from colliding the static parts. It would seem it doesn't matter much even if they do collide for some reason, at least with the fairing. Ah yes, I see what you did with the middle fairing. Doesn't even look bad used like that. The bearings are way smoother with the nosecone being static and look a lot more stable too. And less draggy. Thank you again for your help! It's been really helpful understanding how KSP handles these things, and more importantly that the plane flew just fine hah The spinning nosecone idea came from the electric fairing bearings people seem to use a lot, and they separate the nosecone too it would seem (or at least it wiggles in air a lot). I though it would provide support in high G as the cone collides with the fairing, but sure enough it is much more better having the cone just static. I see no vibrations going at high blade angle higher speed and high G. Edit: forgot to mention that it's a lot more fun to fly now too as it would seem the engines like being without the nosecone and you can turn and turn without any problems. Put in some flaps and offset the propeller a bit outwards and it's great.
  6. Thank you! I took a quick flight without SAS and indeed it is quite logical. Just needs some flaps to be able to land easier I guess. Wouldn't want to give more control authority to the elevator as I fly with a keyboard and it's nice and slow now, but will need something to point the nose up at slow speeds. It really does seem the lift & drag arrows are just not drawn. I flew away from KSC, toward west, and they all show as supposed. Turn to east and they get messy. I will take a look on that fairing thing. If you mean the axle & bearing parts that are inside the fairing generating drag then I'm not actually sure what it should or shouldn't do. As the axle separates, the parts are still kind of inside the fairing, but some time ago when doing a "re-entry box" with a door & "claw" made from elevons I noticed that at least heat effects pass through everything if the parts are not the same craft / docked. Same for aero? The middle fuselage fairing is probably useless, it was to allow me to attach the Wheesley plus a nocelle in front and in the hopes the fairing would take away any drag the Wheesley would generate. But it seems it doesn't. Also thanks for explaining what the part clipping actually means I haven't enabled it as surface attaching with EEX has done the job (plus that I didn't know obviously, but didn't need to look for ways to attach things like that). I get it now and how you explain it sounds it can be very useful in some contraptions to reduce drag.
  7. I've never tried to make a great flying prop plane, but now trying to tune a design to fly straighter with both throttle on and off. With throttle on everything is just fine in pretty much all speeds, but throttle down enough and the thing pitches down quite bad. I have the main wing angled 5deg, tail is horizontal, like are the engines (except for what they flex). I am looking at Aero arrows with F12 and I see this: That seems to be the case in all orientations except when going vertical, then the yellow lift vectors are quite even. I've noticed this plenty of times, but never thought anything of it. In the above image the plane is close to horizontal and so are the engines and it does a decent job of going straight without elevator trim, but only when given power. I understand the receding blades producing less lift, but when everything (except the wing) is horizontal that shouldn't be the case in my mind. If I enable the Aero info on parts and select a blade I see constant lift & drag values that don't change during a rotation of the prop. I tried to pause the game to get the selected blade to be without that yellow vector and sure it still read the very same figures. Is this just an UI issue with KSP or am I not understanding something? The pitch down tendency when power off would be understandable with uneven thrust from the props, but not sure if that's the case. Thanks in advance for any help! The plane at KerbalX. Main wings are a little too far back in the craft file though flies ok anyway.
  8. Continuing work on the cyclic swashplate + collective tail. Got something that you could say is a proof of concept working for the tail rotor part. The cyclic swashplate needs redoing and perhaps replacing the "swashplate" with a decoupler too to get it more compact, though I guess it has more friction to it. At least the tail rotor proto is tough to get turning, and then it explodes Craft in KerbalX in case someone's interested.
  9. @Bubbadevlin Thanks for the pic, I need to try that out! Here's a short video of one I made to show what I mean: Link to video (imgur embed went wrong) This one doesn't go that fast, but might keep a lightweight plane afloat. 14.14rad/s seems to be the maximum with these wheels in this configuration, but all wheels tend to do this and there may be tricks to get it turn faster.
  10. Can you post a screenshot of one of these contraptions? I have not exploited landing legs, but non-powered wheels at a slight angle provide a pretty sizable force with which I've ran some propellers with.
  11. Looks great, good luck with the gearing! Just wondering here thinking the shape of the gears, would the thrusters be shaped more like real teeth if turned 90deg, sideways, thruster port facing up/down? I went through the parts and looked at which would most closely resemble actual gear teeth, but I think I didn't take try those at least not sideways.
  12. I've tried that grabber for really well working pivots for heli blades or a for a part of a swashplate, but the tricky part is getting KSP reliably lock the other part in the same place each time. Depending on gravity / orienation / whatever, it seems it is not very consistent. That plus the pain of manually adjusting everything via trial & error - checking how it is in game, then back to junk yard to fiddle with other parts. Works really well though when you get it right, just too much pain for me =)
  13. Welp.. It seems I need to do a spam post - I hope you mods don't get angry even I was just told the reason for the 5 post limit above. I would like to set my signature to KerbalX site and seems I need that 5 posts to be allowed to set it. Thanks for understanding! So that this is not completely spam, here's a pic of a dangerous meteorite that since the physics engine upgrade does a random direction & amplitude jump upon physics ease-in (part of the reason Jeb is tucked away safely on Eve):
  14. Thank you! Well, seems the "Guidelines" link was too easily found as it usually is the case with things you can't find... One more post to go after this. With the previous posts the mods were really quick though. To keep Jeb safe from crashes he's stationed on Eve, indefinitely. I am having fun, not sure about him :-)
  15. Long time KSP player and now a constructor of Kraken-powered contraptions. I see my posts need moderator review - perhaps this post is required? Thanks for the awesome forum and all the awesome KSPers here providing new innovation and sparking inspiration to do and build things!
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