KSP Loading... Preview: Turbine Engines

[Chel]

Just now, JERONIMO said:

what i mean is that you can but it will be boring to play without dlc's

yeah, and stock ksp is so boring. 'this craft requires making history and breaking ground to use' 'new propellors only available through a DLC'. *sigh*

[DriftedCougar]

Atleast we can make helicopters with 8 blades.....oh and small dragonflies!

[Enceos]

They got sounds?

[Azimech]

9 hours ago, Noir said:

Not to be a downer, but when I heard that stock propellers were coming in a future update I expected them to behave more like how modded prop engines do, like in Airplanes Plus or KAX. That is, effectively like a jet engine in game. I can't help but feel these won't work as well as they should. I already known they won't work in FAR all that well. And the fact the Propeller blades themselves are a fixed shape and length, suggesting there will be limited customisation and creativity. Plus the current Breaking Ground rotors already struggle when spinning at a high RPM, and just turn into a glitchy mess. Makes me wonder why they didn't just go down the Airplane Plus route. I guess on the bright side they won't be charging another $15 for content we've been waiting years for.

Props work fine with FAR. Built and flew the first ever mod turboprop in 2014.

[Azimech]

@RoverDudeany chance the 50 rad/s limit can be increased? It's high enough for a helicopter, way too low for a propeller to be useful.

Now I know how to edit a part to increase lift and change the CoL/CoM to get the required thrust but this feels more like cheating than else.

A prop just needs to run between 2k and 3k rpm.

I hope one day KSP/Unity will be able to handle collider interactions at this rate.

 

[T1mo98]

4 minutes ago, Azimech said:

@RoverDudeany chance the 50 rad/s limit can be increased? It's high enough for a helicopter, way too low for a propeller to be useful.

Now I know how to edit a part to increase lift and change the CoL/CoM to get the required thrust but this feels more like cheating than else.

A prop just needs to run between 2k and 3k rpm.

I hope one day KSP/Unity will be able to handle collider interactions at this rate.

 

Why would they make an engine and props to be used as a turboprop that would not be powerful enough to actually function properly?

Seems a bit silly to say that the engines and propellers designed specifically for this won't be powerful enough.

[Azimech]

1 hour ago, T1mo98 said:

Why would they make an engine and props to be used as a turboprop that would not be powerful enough to actually function properly?

Seems a bit silly to say that the engines and propellers designed specifically for this won't be powerful enough.

These are turboshaft engines. The difference in concept is minimal, the big difference is rotational speed. A helicopter rotor works at much lower speed but the engine delivers much more torque. Why is that? Because a rotor has a much larger diameter to produce the required lift. If you would decrease the rotor diameter you would have to increase the rpm, to a point the tips would exceed Mach1, limiting lift and produce a noise way beyond acceptable.

With a turboprop it's the other way around. A propeller is not at max efficiency while the plane is stationary. It has to move and change its pitch to match every speed regime. It also needs a high rpm otherwise the blades will stall. 

Therefore: using a turboshaft with a max rpm of 477 (the current game limit) to propel a plane with a normal diameter prop might give it the ground speed of your grandma's sedan.

 

[Tonka Crash]

The comments on the prop rotational speed seem kind of premature. Real world engine rpm is for real world aerodynamics where you want to spin the prop as fast as possible without the tips going supersonic. Instead of a speed of sound limit we have a Unity RPM limit, it's just a different constraint. 

These props don't have to obey the physics of air flow around an airfoil to produce thrust. They follow whatever thrust curve is programmed into their .cfg files. Even if Squad screws this up, all it will take is a MM patch to change the prop thrust curves. 

What I'm curious about is if there are multiple engine sizes with different power outputs to use the different blade sizes. 

[Azimech]

8 minutes ago, Tonka Crash said:

The comments on the prop rotational speed seem kind of premature. Real world engine rpm is for real world aerodynamics where you want to spin the prop as fast as possible without the tips going supersonic. Instead of a speed of sound limit we have a Unity RPM limit, it's just a different constraint. 

These props don't have to obey the physics of air flow around an airfoil to produce thrust. They follow whatever thrust curve is programmed into their .cfg files. Even if Squad screws this up, all it will take is a MM patch to change the prop thrust curves. 

What I'm curious about is if there are multiple engine sizes with different power outputs to use the different blade sizes. 

Yes, I already wrote it's easy to write a part that works with KSP's errordynamics. In fact I know more than most. I invented the stock turboshaft/prop, the variable pitch propeller and held the stock turboprop speed record for a few years.

What is even more interesting if the limit goes up, it opens up other possibilities like smaller & lighter stock piston engines.

[Snark]

A whole bunch of content has been split out of this thread and moved to a separate thread:

Folks, just a gentle reminder that this thread here is for discussing the new engines.

This is not a thread for arguing about whether businesses should charge money for the products that they produce.  There's nothing wrong with debating that topic, but this thread is not the place for it; it's off-topic here.  So if you'd like to discuss that, please take it elsewhere (e.g. to the separate thread linked above) rather than derailing this thread over it.

So, to be clear, on-topic for this thread includes discussing the parts themselves (e.g. if you like them, or don't like them, or have ideas for how to use them, or have feedback about the design or functionality, or what-have-you).  "Should it be part of the stock game", or "is it okay that DLC costs money", or any of that sort of stuff, is off-topic here, so please take such discussion to another thread, such as the one linked above.

Thank you for your understanding.

[Serenity]

I have no idea how they work or how i am gonna use them but i dont care!Only the word ''engines'' is music in my ears, thank you!

[Kerbart]

Can't wait for someone to hook up wheels to those bad boys.

[Aegolius13]

19 hours ago, JPLRepo said:

LF and IntakeAir

Would love an alternate mode to let them run on LFO.  Eve is crying out for these things.   Though I suppose the fuel efficiency would be rather not-good.

[Snark]

30 minutes ago, Aegolius13 said:

Would love an alternate mode to let them run on LFO.  Eve is crying out for these things.   Though I suppose the fuel efficiency would be rather not-good.

That certainly sounds potentially useful.    Out of curiosity, has anyone tried the current electric rotors on Eve, and hooked them up to fuel cells for power?

Am curious how well that works (or doesn't)-- haven't had a chance to play around with rotor-powered craft much, yet.

(I hasten to add that I'm not looking to start a side discussion-- let's keep it on topic!  Just, if someone has tried that and has feedback about "yeah, it works great, I don't think we need LFO rotors" or "it's not so great, we really need LFO rotors too", that's really all I'm looking for.)

[Raptor9]

9 minutes ago, Snark said:

Out of curiosity, has anyone tried the current electric rotors on Eve, and hooked them up to fuel cells for power?

Am curious how well that works (or doesn't)-- haven't had a chance to play around with rotor-powered craft much, yet.

I put a pause on rotorcraft experiments shortly after starting.  I found the electric motors, especially the small ones, to be relatively weak at maintaining RPM when torque is applied.  With my test helicopters, which were rather small, initially they leaped off the ground as the blade pitch increased, but then came crashing back down hard to the runway as the drag from the "rotor blades" caused the RPM to spool down.

So I'm hoping the new engines have enough torque to maintain said RPM's since they are LF-powered instead of just electric.  I'm also hoping that the rotor/prop blades mounting strength is strong enough that they don't get pulled away from the rotor hub from centrifugal forces, as seems the case with some contraptions currently.

[Anth]

@snark isnt the fuel cells just to charge the batteries? As long as they can charge the batteries fast enough there shouldnt be a problem right?

Heres something you may or may not seen.

My paddle boat uses battery power via the solar panels only. the reaction wheels are what makes the paddles work with the servo just for rotation. (works better than my kraken tech attempts)

Physwarp Powered by the way

 

Edited July 5, 2019 by Anth12

[Aegolius13]

10 minutes ago, Snark said:

Am curious how well that works (or doesn't)-- haven't had a chance to play around with rotor-powered craft much, yet.

Not quite responsive, but ShadowZone did an interesting video with a solar-powered Eve quadcopter.  He had four gigantors, each feeding one rotor.  Some old info states that a gigantor produces about 14 pirate-ninjas ec/sec on Eve's surface, with 100% exposure.  So that's a little less than a fuel cell array.  Assuming one array can serve one rotor, if I have my math right, consumption would be 0.045 units/sec combined LFO per rotor, or 2.7 per minute, or 162 per hour.  That's not bad, considering he used an hour (so ~650 units LFO) to get up to 19km altitude.

https://www.youtube.com/watch?v=uXdC1F6Ss2k

 

[Anth]

@Raptor9Thats why I went with reaction wheels for my paddle boat. My inital testing showed the rotors couldnt spin fast enough

[Raptor9]

@SQUAD, another concern I have is the lack of a 0.625m equivalent to the R121, which is displayed as "1.3 m" in diameter (I assume that 1.3 is just rounded up from 1.25 meters). Ideally, for small Mk1 fuselage based aircraft that use the 1.25m crew cabins and fuel tanks and such, a 0.625m engine nacelle should be an option as well. Otherwise you end up with rather oversized engines and less build options for small aircraft layouts.

I could be jumping the gun on this one since the lack of a 0.625m engine in the preview image doesn't mean there isn't one in the works, but I figured I should bring this up earlier rather than later.

[KerikBalm]

1 hour ago, Snark said:

That certainly sounds potentially useful.    Out of curiosity, has anyone tried the current electric rotors on Eve, and hooked them up to fuel cells for power?

Am curious how well that works (or doesn't)-- haven't had a chance to play around with rotor-powered craft much, yet.

(I hasten to add that I'm not looking to start a side discussion-- let's keep it on topic!  Just, if someone has tried that and has feedback about "yeah, it works great, I don't think we need LFO rotors" or "it's not so great, we really need LFO rotors too", that's really all I'm looking for.)

Current electric rotors work quite well. I've seen them used for an 8 ton to orbit Eve ascent vehicle (1 kerbal capacity).

For my part, I wanted to use them for flying around the surface:

Carrying a jumbo tank:

However, I could always use more power. That craft does over 160 m/s on kerbin (with no payload), but here it was doing just over 90 empty (may have gotten faster if I climbed more, I'm not sure).

Instead of an LFO engine (which just saves part count from fuel cells if the torque to weight ratio is the same), I'd like a monoprop powered engine, so that... you know, monoprop actually gets some use (plus it makes a lot of sense, it may simplify the engine as you don't need to get 2 things well mixed in the right ratios).

I really hope these engines have a better TWR than the electric rotors, but I don't care so much, as I'm interested more in props and helos for use on Eve, Duna, and mod worlds like Tekto, where these engines won't work.

[Azimech]

9 minutes ago, Raptor9 said:

@SQUAD, another concern I have is the lack of a 0.625m equivalent to the R121, which is displayed as "1.3 m" in diameter (I assume that 1.3 is just rounded up from 1.25 meters). Ideally, for small Mk1 fuselage based aircraft that use the 1.25m crew cabins and fuel tanks and such, a 0.625m engine nacelle should be an option as well. Otherwise you end up with rather oversized engines and less build options for small aircraft layouts.

I could be jumping the gun on this one since the lack of a 0.625m engine in the preview image doesn't mean there isn't one in the works, but I figured I should bring this up earlier rather than later.

Yep.

[JERONIMO]

Now we just need a 2.5 m rotor.

[Guest]

3 hours ago, Snark said:

That certainly sounds potentially useful.    Out of curiosity, has anyone tried the current electric rotors on Eve, and hooked them up to fuel cells for power?

I have. They work great. I made a sea level to orbit lifter that weighs < 6 tons, a fully reusable two-stage lifter (if you have the patience) and a bunch of others. Follow the KerbalX link in my .sig for craft.

[The Dressian Exploder]

On 7/4/2019 at 9:29 PM, St4rdust said:

Also emits a pleasantly high pitched whine.

NNNNNeeeeeeeeoooooowwwwwmmmmmm

[FahmiRBLX]

I wonder if a planetary gearbox (Similar to Tupolev Tu-95's contra-rotating propellers mechanism) would be added in the next update.

@St4rdust, what do you think?