Helicopter - Blade Authority? KAL Use? HALP!

[JoeSchmuckatelli]

EDIT: OP in SPOILER below.

 

Holy COW!!!!

I got one to work!

(And it doesn't look like a jalopy!)

 

 

 

Spoiler

Well - Since I started this thread, and cannot delete it... I'm going to change it to a frustration blog for anyone else going through trying to get helos to work in KSP.  Feel free to criticize, suggest or kibbitz!

Okay - Here's what I'm learning... helicopters in KSP are not easy.  -- the info I provide is from watching a whole bunch of videos and trying to get the damned thing to work.  This is in part because building one and getting it to work is completely different from anything else in KSP that a duffer rocket launching player (like me) has faced before.

• First off: when you attach a helicopter or ducted fan blade or any propeller to a rotor, know this: they're NOT deployed by default.  You have to do that manually.  Left click and hit "Deployed" pretty much as soon as you place them.  If you don't deploy them, nothing else you do will matter / work.
• Also - more often than not, when you attach the blades to the rotor, they'll be facing in some ungodly unhelpful and useless direction. So you not only have to play around with the left click menu, you have to first make sure you put them on correctly in the first place. 
• Reminder - if you accidentally pick up the blades instead of right clicking or programming the KAL... You might get to repeat the preceeding steps. And... Even if you fiddled with the placement and everything looks right - if you don't have 'inverted' or 'deployed' correct on all... Something won't work. 
• Next: building a 'traditional helicopter' in KSP (one with a main rotor and a side facing tail rotor) looks to be an effort in absolute frustration.  Probably because Mouse and Keyboard don't offer a ready ability to nurse the collective and control torque at the same time.  Thus, most working helos in KSP probably look like dual rotor (think CH-46) helo or something like an Osprey.
• You have to use different KALs for different things. 
  • Like one for blade pitch - which in a helo should start off at 90, and according to one vid, stop at 85... I'm still playing with this.  - - okay this is not correct (the vids are in many ways wrong because of changes to the game) - so you have to fiddle with blade DEPLOYMENT (not authority) and you want some small amount of negative blade deployment and about double that in positive) 
  • I've got the main throttle keyed to control this blade deployment KAL using 'Play Position'.
  • Another for torque / RPM control - one guy suggests a value (flat) of 8... I'm still trying to figure this out as well.  I've got 'Translate u/d' assigned, again with play position so that I can control RPM  - - this is a little weird b/c you don't get feedback on screen as to where you have the RPMs set... But it can work just fine 
• You have to invert one set of blades and also invert the associated rotor.  You need to thus, place individual rotors separately and individually to program them.  Don't use symmetry. However, the 'Blade pitch' KAL can control all blades at the same time, just as the 'RPM' KAL can control both rotors
  • You may discover on the launch pad, that despite your best intentions... you've inverted the wrong rotor!  Back to the VAB!
•  You have to be absolutely certain that your COL is matched up with your COM - and that your COM is lined up with your rotors!  Otherwise bad things happen.
• Rotors use electricity.  If you're at a mid-tech level (as I am) you need to think about storage and generation when building the dadgummed thing.
• You have to account for Kerbal (crew) weight during your build... Make sure you have a crew selected when looking at COM / ROTOR placement

I've gotten a two-counterrotating blade helicopter to take off.  Trick was, the top rotor needed to be powered and the bottom unpowered, no brakes, etc.  Teasing out getting the thing to work was... interesting.  But.  I forgot that you need to control blade deployment on BOTH sets of blades... otherwise they work against each other... even though you 'in theory' want one set of blades to be passive.

 

 

All of which is to say - I've figured out how to get one off the pad... going somewhere with it will be a different story.  --- Like literally, I can get off the pad... and then it lands itself 30m away!

Well now... I can get off the pad... but not back down again.  Still trying... in the air, but not yet flying!

 

... And now I have a working rotory wing aircraft! 

Spoiler

 

I've got a helicopter... that should work.  But it doesn't.  I've followed a couple of videos, and clearly I am missing something.

I can get the rotor spinning, but I can't get the blade authority to do anything.

Here's what I've got:

• a KAL assigned to the main rotor (R-7000) with Action Group 1 to get it to turn.  This works.
• Action Group 2 assigned to blade brake (separates it from wheel brakes).  This works as well.
• a KAL assigned to the blades.  I've tried both Authority and Deploy angle - but nothing happens when I try to lift (also, whether in the VAB or the launch pad, I never see any animation when adjusting the sliders)
• Main Throttle set to Play Position to control the KAL assigned to the main rotor blades.  At the launch pad, moving the throttle moves the slider... but again, nothing happens.
• Blades are set to rotate clockwise, as is the rotor.

Big question: should I see the blade pitch change when the sliders are adjusted?  (Because I don't).  I've played around with values a bunch too (positive numbers and negative at the end of the slider) - and I just can't get anything to get the main rotor blades to bite the air, regardless of whether there's an animation that affects the blade pitch.

 

If I've left out anything important - I'd really appreciate knowing.  (Recently discovered a hidden place that would be great to visit with a helo!)

 

 

 

Edited May 14, 2020 by JoeSchmuckatelli

[JoeSchmuckatelli]

Update: - I don't know exactly what I did... but I think the problem was Authority.  Deploy angle seems to actually be the control scheme I'm looking for.

-- the next problem is how to get the tail rotor to work.  I know that the normal Throttle controls of CNTRL and Shift give me variable throttle control... but how to I get variable control of the tail rotor?

 

Edit - FWIW I totally feel like this guy (except for the download one part) 

 

Edited May 13, 2020 by JoeSchmuckatelli

[JoeSchmuckatelli]

I've abandoned a traditional helo design; sad, really b/c my first attempt looked cool.  I've now got something that looks like a dude working from a barn in Kentucky built... but I can get it off the pad!

… Just not far.

[BigFatStupidHead]

I believe the KSP difficulty hierarchy goes something like this: Rockets, airplanes, ssto, then helicopters.

They are tricky but you'll get there.

Edited May 13, 2020 by BigFatStupidHead

[Cavscout74]

16 hours ago, JoeSchmuckatelli said:

Okay - Here's what I'm learning... helicopters in KSP are not easy

Well, in all fairness helicopters in the real world are not easy either, so KSP certainly got that part right.

If its any consolation, I've made a few working helicopters in the past but every update, Squad changed something with the props & rotors, and my design would totally break and have to be rebuilt from scratch.  After the second time, it just killed it for me.  

[JoeSchmuckatelli]

15 minutes ago, Cavscout74 said:

Well, in all fairness helicopters in the real world are not easy either, so KSP certainly got that part right.

If its any consolation, I've made a few working helicopters in the past but every update, Squad changed something with the props & rotors, and my design would totally break and have to be rebuilt from scratch.  After the second time, it just killed it for me.  

I noticed that as I began my builds: many of the videos I watched had me doing things that... did nothing.  I've come to learn that when a vid says 'blade authority' they mean deploy angle, etc.

Great idea... but the implementation (and documentation) leaves a LOT to be desired.  At least from an 'ease of use' or 'intuitive implementation' standpoint.  On the other hand, as a 'virtual garage' where I can tinker with all kinds of stuff just to see what happens?  Glaring success!

[JoeSchmuckatelli]

I finally got one to work!

It's got two R-7000s, the full sized blades... and it doesn't look like a total jalopy.

Not winning any style points -- but, hey hey, I got it to take off, move where I wanted to... and then land!

 

Going to eat... then I'll edit this with what I did and what worked... in case someone wants to try this themselves!

 

Okay - here's the build that worked: 

Two inline, but vertically offset R-7000s (did I already write that?) with 4 of the big blades per rotor.  Blades mounted so they looked flat in the VAB / SPH (parallel-ish with the plane).  This makes for a long plane, btw.  Blade deploy angle (RMB menu) set to 0 for all blades.  Front rotor and blades normal deployment direction, with blades in the extended position!  Rear rotor and blades inverted.  The body is based off the Mk2 Cockpit with 2 service bays in the middle flanked by 2 mostly empty fuel fuselages (240 total balanced toward the ends) - the far side from the cockpit uses the Mk2 to 1.25 adapter mostly for looks, capped off by a nose cone.  I write 'mostly' because I found the oxidizer slider to be really useful in helping me shift my COM to align with the COL.  I added Junos (centered, side mounted) with a single fuel Mk 0 fuselage and intake -- for power generation, with the thrust limiter to *eventually* 10 on the left and 15 on the right (helped with torque).  Towards the back I placed a couple of Swept Wing Type Bs to give me a little width for my landing gear and to support a pair of Delta Delux winglets - whether they helped or not, I don't know, I just liked the look.  Service bays held Science Jr, ESU, a pair of Advanced InLine Stabilizers, a pair of Z-200 batteries and the SEQ Container Module.  The outside got sprinkled with all the usual sciency stuff and a pair of the 2x8 solar panels for good measure (But with the jets - I never felt I needed them... and it was night, anyway).

The two KALs separately control 1 blade deployment (both rotors) and 2 RPM & Torque (both rotors). 

• Blade deployment on the KAL was programmed from -10 to 17.  Note: 17 may have been too much, especially at low altitude... but you definitely want some negative to be able to descend with some feeling of control.  -10 felt just right.  I also tied the Main Throttle to control that KAL with the setting Play Position. 
• The second KAL was set to RPM (0 to 460), and Torque at 8, flat across the board.  This also seemed to work quite well.  I then tied it to the Translate U/D controls, again with Play Position.  I did find myself fiddling with torque during the first part of my flight, again at altitude, and a third time when I got stupid and did an Airwolf loop.  Having K&I mapped may have saved my bacon!  Also, it helped to be able to control it via keys during landing and when I wanted to EVA.
• Finally, because my Helo has wheels - I needed to go to the "Brake" action group and unassign both Rotor Brakes from this action group.  This DROVE ME NUTS during the first two helo builds.  For some reason, Rotor Breaks are by default connected to the wheel brakes.  I instead tied them to action group 1, in case I needed it... but I haven't needed it.

The bird flies! 

And a lot easier than I feared.  Taking off and getting up to speed is fiddly, but once you've found a stable spot - it will fly straight and true (yep, you can take your hands off of the M&K)… allowing you to drink a cup of coffee.  Which you will need.  Because it is NOT fast.  It also HATES when you click the timewarp for any reason.  So enjoy 30m/s max with an operational ceiling about 2600m (Guessing - I only needed to clear some mountains, not go to the Mun).  Overall, flying and landing were pretty easy... albeit harder than a fixed wing plane.  And it got me to a cool little spot I discovered in the desert and felt Bob would enjoy exploring.

Edited May 14, 2020 by JoeSchmuckatelli

[AHHans]

11 hours ago, Cavscout74 said:

If its any consolation, I've made a few working helicopters in the past but every update, Squad changed something with the props & rotors, and my design would totally break and have to be rebuilt from scratch.

That's true. But they also added new features that allowed you - well, at least me - to build better, more realistic craft. This allowed me to got from this, to this (eliminating the extra servos), to this and actual helicopter with tail rotor. So I'm not too mad at them.

Some helpful(?) comments:

• Before taking off with a rotor powered craft activate the "Aerodynamic Forces Overlay" and check if the control scheme and thrust direction works as expected. (Well, see the comments above...)
• Rotor thrust (Helicopter main rotor, tail rotor, propellers on a plane, or whatever) is better controlled by leaving the rotor RPM constant and adjusting the blade pitch, than the other way around. This gives better and faster control with less side effects. (Well, having the RPM drop because the engine doesn't have enough torque is usually fine.)
• Control direction matters. My craft only work with the control direction in one direction (for the quadcopters up, for the Heli forward) because with changing direction the axis "names" change (yaw becomes roll etc.) and the assignment of the axes to the controls get messed up.
  Also control up lets you set SAS to "surface" - "radial out" and thus have it keep your craft from getting into a position where it cannot generate lift anymore.
• You can get feedback on settings like max-RPM, rotor-torque, deploy-angle etc. by opening and pinning the PAWs in flight.

[Rpatto92]

@JoeSchmuckatelli hey, if you're still building a helicopters in 2023. I've wrote a comprehensive guide for working around these problems ksp. 

here's a link: