_Rade

Other than that heli in the post above, I've been using the fairings to build plane propellers, and propeller blades usually don't bend. Other than autostruting the blades to the root part inside the rotor I'm not sure what else you can do about it. On the propellers I use, usually there is long or short I-beam as the root part and 2 or more stayputniks acting as the bearings. Also on the front of the propeller there is small docking port which sort of acts as the buffer or a spring and the front stayputnik is pushing against it. Otherwise if the front stayputnik is pushing on the part on which the faring is closed that can cause the vibrations in the faring which in turn usually transfer to the rotor. @Gman_builder I know, but effectively the end result is more or less the same.

@The Optimist what kind of issues are you having with the fairings I might be able help with that.

Twitchy SAS moving the elevons trying to maintain the stability. This causes the heli to pitch up or down or roll and after that it is almost impossible to recover it. While it is level the yaw works fine and you can turn the heli just using the rotor tilt. One thing I didn't try is to disable the pitch and yaw on elevons and to deploy them with action groups, but that would make flying this even bigger challenge. Here is the craft file if you want to try it https://kerbalx.com/Rade/Copter

I'm guessing he means being able to tilt the whole rotor around, the way the real helicopters do it. Few weeks back I've made this ugly contraption. You can tilt the rotors but the damn thing is nearly impossible to fly or control. The way this works, there is a single stayputnik inside the the fairing and below it there is small LF tank attached to it. There is also 4 elevons around it so when you pitch or yaw the elevons push the fuel tank around and this causes the rotor to tilt in the direction you want to move. After seeing the post by the @EpicSpaceTroll139 I've tried replacing the fairing with the structural fuselage to see if that will help. But there is almost no difference. Problem seems to be caused by the SAS acting up on the elevons and the vibrations from the fuel tank colliding with the elevons.

I had one version where the rotors would spin reliably but just not fast enough to liftoff, but I forgot to save that version. While trying to adjust it, in order for the rotors to spin faster, I've only managed to make it worse and now rotors pop from the bearing as soon as the engine reaches full power. @Azimech I'll try it out. There is few things I wanted to build with turboprops, but I really couldn't deal with the low fps.

I've tried building the turboprops before but my laptop really couldn't handle all the particle effects from the engines, so I decided to stick to the trusty SAS wheels for now. Anyway I've tried to modify your heli in order to turn it in to something similar to the Kaman K-MAX in order to be able to run both rotors with only one engine. But I've must have messed up something with the bearing, because I couldn't get the rotors to spin fast enough for the heli to lift off. Here is a picture. Maybe you'll be able to get it working. Let me know if you want the craft file.

It's good to see that the mission is progressing nicely. Did you find any good locations to land the base, because finding nice flat ground on Duna is mission impossible.

In my experience faster the prop is moving the better thrust you get from the blades. I did a quick little experiment to test the lift you get from the rotor blades. First engine uses 4 blades placed close to the rotor axis, it is powered by 20 reaction wheels. The second engine uses 2 blades which are slightly offset from the rotor axis, and it is powered by 26 reaction wheels. Second engine had to be slightly more powerful in order to be able to spin at same speed as the first engine. Anyways, even tho both engines are spinning at the same speed, the blades on the second one are generating approximately double amount of lift compared to the blades on the first engine. And that's only because the difference in speed between the blades on two rotors. Also here is another example on how to determine engine thrust. The plane is flying at it's max speed, on the panel on the left total drag for the plane is ~17.2kN, so in order to keep flying at that speed the engines must be able to provide same amount of thrust. On the second picture one of the rotors is selected and the panel on the left is showing total drag for the rotor as negative ~8.6kN and total lift as ~1.9kN. I'm guessing the game is confused by the rotors and that's why it the drag is negative. But if you multiply that drag by 2 you'll get almost exact match for the drag created by the plane. There is also little bit of the drag caused by the propeller blades (6*0.22kN) and by the nosecones at the front of the rotor (2* ~0.35kN) which gives us the total drag for the plane at 19.22kN. In other words each engine produces about 9.6kN of thrust at the max speed for the plane. Not counting the fairing the TWR for just the engine is 0.48.

The amount of lift you get depends on how fast the propeller blades are moving, so it makes sense to move them further away from the rotor axis. That way, if you assume that in the both cases the propeller is spinning at the same speed, the engine with the prop blades further away from the rotor will have more thrust. What might be happening is that engine that you're using doesn't have enough torque to spin the propeller at the full speed when the rotor blades are moved further away from the rotor axis. But when you move the blades closer the engine can spin them faster and they provide more thrust. For example small engines that I'm using, they have 20 reaction wheels, when I put 3 propeller blades on them they work great at low altitude, but lose thrust at higher altitude. That is because the propeller can spin close to the 50 rad/s (which is the max rotation speed the game allows) at low altitude, but if you go higher the propeller is still spinning close to 50 rad/s but the propeller blades provide less thrust because the atmo is less dense. However if I put 5 propeller blades on this engine, it will have lower speed at low altitude and higher speed at high altitude. Because now the engine can't spin the 5 bladed propeller at full speed at low altitude, but if you go higher the engine can spin the prop close to 50 rad/s and 5 bladed prop will give you more thrust than 3 bladed prop, simply because it have bigger surface area. I hope this helps. btw. how did you manage to measure the thrust on the propeller?

Back at the KerbalX @Gman_builder mentioned I should post this here. Stock fighter plane powered by the electric fairing propeller engines. These engines use 1.25m fairing as the engine housing, instead of the structural fuselage typically used to make the stock propeller engines. Because the fairing occludes all of engine parts from the drag you can build planes that can fly much faster. Also stayputnik probe core seems to be perfect fit for the fairing collider, therefore rotor can spin really fast with almost no friction. In fact on the early versions I had trouble with the engine disintegrating from overspeed if I tried to fly the plane at higher altitude. Latter I've managed to fix this by adding the I-beam as the root part for the rotor, and then autostruting everything on the rotor to the root part. I've already posted several other airplanes which use these engines on the topic about the stock electric propellers. Ik-5 is powered by two of these engines, each engine uses 20 small reaction wheels. Thanks to the low drag it can reach speed of 192 m/s at low altitude. Few other planes I've made can fly at 200 m/s or slightly faster, and the fastest one is able to get to 240 m/s.

It's great to see that the plane is working and that the landing went without problems. Have fun flying around Duna. If I find some time to play the career I'm definitely gonna send one to grab all science on Duna. nice logo btw.

Nice to see you had better luck with the engines than I did. Have fun flying around Duna.

Problem with the docking ports is that they have to move away from each other a certain distance before they can redock. Unless you can do something like that you wont be able to redock two parts. For the Dunasoar I've used the claw located inside the engine nacelle to grab the rotor when the plane is not in use. It works quite well, only downside is the engine have to be considerably bigger because you have to fit the claw inside the fairing.

Did you check it the fuel flow is enabled on the structural pylons. That might be preventing the fuel transfer.

I've updated both versions of the plane and I did a little bit of testing and they seem to work fine. One thing that I've noticed is that left engine seems to spin just slightly faster than the right one. Not sure yet whats causing it, but it shouldn't cause much trouble in flight.

Everything on the plane that needs struts is already autostruted. Only place that could use the struts is that octagonal strut that holds the engines. If you can strut it to the fairing that is attached to it that might help. Maybe you'll just have better luck with the engines than I did. I'm gonna go and modify the plane to get rid of the octagonal strut, should have known using that on the engine is a bad idea.

I'm glad I could help with the mission, I'll be watching to see how the mission turns out. Hopefully you can find some good uses for the plane.

Nice, I'll be watching the tread to see how it all turns out. Hopefully you'll have better luck with the engines than I did. I think it might have been better to attach the nose cone to the wing, offset it back and then attach the engine nacelles to it. That should have stronger joint strength than the octagonal strut that I used to attach the engines.

It could be done, only problem is that with the push props on the tail it is really hard to takeoff even from the runway. Can't imagine how that would work on the bumpy terrain on Duna. Back in 1.0.4. I've sent similar plane to this one to Duna. First I've tried to send it on top of the rocket, but that didn't work because the COL was so far ahead of the COM. Then I realized that in order to get into orbit the plane will have to fly backwards. I've made the similar rocket for the Dunasoar and I've replaced the fuel cells with the RTG's. You can checkout the imgur album for more details. http://imgur.com/a/gVQvi craft file https://kerbalx.com/Rade/Dunasoar-with-launcher There was few other unsuccessful prototypes before that, but that is the first one that worked well. After that I made the smaller engine where the fairing cowered the structural fuselage that held the rotor. This eliminated the drag from the engine parts and in turn you get much higher speeds from the plane. Final step was when I realized that you can get rid of the structural fuselage and just use the fairing instead. This worked much better than I expected, because the fairing props for some reason can spin much faster without breaking and they also have very little drag. btw. anyone knows how to embed the imgur album.

Glad you like it. The engines on it are little bit under powered for flying on Kerbin, mainly because the more powerful engine would spin to fast in Duna thin atmosphere. But if you fly it properly it should be able to get to atleast 90 m/s. Also in case you want to make some changes to the plane, just make sure that you rebuild two inner fairings on each engine after modifying the plane. This have to do with buggy fairings and it will ensure that both engines continue to work properly. If you like the stock prop planes you can checkout my KerbalX page, I have few other planes that can fly faster than 200m/s.

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.

These two planes use stock propellers, where the propeller is a separate from the main craft. So it's not exactly easy to throttle them down. It can be done but I usually run them at full power and just turn them off for landing, or engage the SAS to stop the rotor from spinning altogether. The planes have fairly large wing area so you can nicely glide in for the landing. Problem with the nose-diving was that once the plane would touchdown in the water, the front of the plane would sink more than it should and the drag from the water would cause it to do a front flip and end up on its back. Adding the NCS adapter to the plane nose fixed this, although it still can happen if your landing speed is to fast.

Made one seaplane and fixed the fuselage on another one. Just replacing the advanced nose cone with the NCS adapter fixed the problem with the plane doing the front flip when landing on the water. It turns out the NCS adapter floats much better. https://kerbalx.com/Rade/Catalina https://kerbalx.com/Rade/Galeb

About the blade pitch, usually I set it to 30 degrees to the airflow. But I only use this on takeoff, for flying I usually set the authority limiter to -70 to reduce the blade angle. If the engine is powerful enough you can set the authority limiter up to -90 to get some extra speed. I try to optimize the engine so that it can reach the max speed with the authority limiter set to -70. That way I can use the higher blade angle for takeoff, and then just toggle the cruise mode via the hotkey. No need to fiddle with the authority limiter slider in flight. Today I finally managed to build a working seaplane, it can carry 6 Kerbals at max speed about 150 m/s. It took me quite a few tries to find a hull configuration that can land on the water without doing a front flip or destroying the rotor blades. Also I'm not sure if this is some sort of a bug or something else. After the first water landing the plane could takeoff with only about 50% trim on each engine. After the second water landing I had to give it full trim on the engines in order to takeoff and the plane couldn't reach its max speed. I'll have to do some more testing to find the cause to this. https://kerbalx.com/Rade/Galeb

For me the record was 200 m/s, alto few pages back there was this crazy contraption that could reach 220 m/s.