New to helicopters

[Humpty 751]

Deleted the pref for the 22. Hmm at least now it has not kissed the ground. Gonna try some more and make sure that was the reason.

 

[MrBitstFlyer 3,894]

What a challenge the helicopter is! I've managed to get my hovering diameter from about half a mile to 50ft or so 😁😬!  What I am really failing at is descending and slowing down for the landing.  I lower the collective and pitch back but the rate of slowing down is painfully slow.  I lower the collective even more and pull back to slow but I sail past my aiming point. several times my RPM has dropped to set of an alarm and I crash.

Watching  real helicopters go from fast to a landing quickly is quite embarrasing.  Anyhow, I'm enjoying the new challenge immensly!

[Bulva 98]

39 minutes ago, MrBitstFlyer said:

.  I lower the collective and pitch back but the rate of slowing down is painfully slow.  I lower the collective even more and pull back to slow but I sail past my aiming point. several times my RPM has dropped to set of an alarm and I crash.

We had to train in the same school, because I have exactly the same "technique" of landing    😉 . 
The "technique" of what should be landing... 😉

[Bjoern 1,158]

Had issues with my TWCS throttle, which felt sticky despite greasing the rails a few months ago, with erratic potentiometer readings in some areas, so I cleaned out any excess grease and loosened the screw of the potentiometer lever arm a bit. All of this greatly improved things. Then I found a new, more comfortable position for my rudder pedals, farther away than before, improving input granularity due to more horizontal pushing action and less downward pressure action from my feet.

To test all this, I loaded a benchmark application for control devices in XP - helicopters. I also hadn't really tried the new NaturalTracker filter in Opentrack yet, so I set up headtracking alongside.

Any my, what a world of difference all that made.

First, I've tried to get to grips with VSKYLABS' R66, but its failure modeling is very touchy, with an instant engine fire if throttle is increased just a bit too quickly. But it admittedly handled comparatively well from takeoff to descent. But the tendency to enter vortex ring state made landing attempts frustrating.

So I thought "screw it" and loaded up Robinson's Deathcopter I cursed out so often. First attempt, tipped over trying to take off. Second attempt, went all over the place trying to find the right moment to counter torque with the tail rotor, but got airborne. Then I picked up some speed and started flying around SFO. First, down the runway, then back down the parallel runway. This went rather well, so I tried following taxiways. At first at a fixed collective setting, not caring about altitude changes in turns and staying on center and then gradually taking the tighter turns and starting to use the collective. The more often I did this, the less I stopped caring about what exactly the helicopter did and just tried to make it go to whatever point I looked at. Headtracking helped immensely with that.

My hovering and landing attempts were neither elegant nor safe, but I at least got down without crashing a few times. Taking off and landing still needs work.

Then I tried landing on the frigate and carrier in the bay and...

 

This was without any funky, unsafe things. I approached, used the carrier bridge as a fix point and simply inched closer above the cables, trying to stay in position Then, I picked a spot on the deck near the cats and tried to keep it inside the front window and...landed. No bounce, no thump...just landed. Admittedly, the moving carrier made everything easier as some forward speed is quite useful to escape VRS, but still I feel like a ten year old having knocked out a kickboxer.

Before that, I actually tried landing on the frigate, but sadly fell through the deck just as I was setting down. Bummer, as this would have been the crown on the strawberry.

What I still have trouble with is finding the right moment to compensate with pedal input when taking off or a very low velocity. The R22 is quite abrupt going from zero to full input and it's quite hard to gauge correctly just when it will start turning when applying collective. Are there cues to look out for apart from movement?

Next, are there grace requirements for helicopter flying? I was flying with real weather and wind and just let the R22 weathervane as long as I went where I wanted it to go, not paying much attention to keeping the tail boom exactly on my movement vector.

While I think the R22 and I have a long way to go, it redeemed itself a good bit with this fun, but quite tiring (no trim and a T.16000M is quite stiff) flying session immensely. Let's see if I want to take it out more often now.

[mSparks 2,094]

51 minutes ago, Bjoern said:

What I still have trouble with is finding the right moment to compensate with pedal input when taking off or a very low velocity.

there is something not quite right in the behaviour there, not really worked out what.

In the 44 you set left pedal about 2 or 3 inches in before lift off and it more or less stays there into the hover.

[Bjoern 1,158]

16 hours ago, mSparks said:

there is something not quite right in the behaviour there, not really worked out what.

In the 44 you set left pedal about 2 or 3 inches in before lift off and it more or less stays there into the hover.

Maybe the tail rotor in the ACF file of the R22 is too big or so?

[mSparks 2,094]

36 minutes ago, Bjoern said:

Maybe the tail rotor in the ACF file of the R22 is too big or so?

reading again what I wrote, I wasn't particularly clear, so I'll try again and be more precise.

For the actual R44 the school taught a "10 point" check list to remember by heart right before before going into a hover (after the actual check list is complete)

1. Friction 1 confirm off

2. Friction 2 confirm off

3. confirm panel all lights out

4. check temps and fuel guages (really check, they sometimes test you do this one by pulling a breaker just before lifting off)

5. center cyclic

6. confirm area clear

7. confirm engine and rotor speeds,

8. left pedal about 2 or 3 inches forward of right pedal

9. find close reference point

10. find distant reference point

Then lift collective slowly into hover, left skid low. (been 6 years since they taught me that, not 100% sure I remembered everything correctly..... 😞 )

when you get the pedal input correct there is no pedal input needed, it gracefully lifts stably into a hover, I've never managed that in X-Plane, it always needs some pedal variation very shortly after take off - which is what I meant by "there is something not quite right in the behaviour there, not really worked out what"

I suspect it is governor behaviour related (which I already posted my attempts at resolving other governor issues somewhere in here, but the one I am currently using is still not perfect), such that throttle input is changing when it shouldn't.

Edited September 2, 2023 by mSparks

[Bjoern 1,158]

"Left skid low" is a great tip. Adding a bit of left cyclic before lifting off, combined with the preemptive application of some left pedal makes taking off in the R22 easier. The "bump" after liftoff is still throwing me off a bit and as it happens also when landing, I haven't managed a clean touchdown yet.

The governor behaviour is definitely weird, with lots of overshoots when increasing throttle and an inexplicable sudden decrease in manifold pressure in the first third of the axis range. Laminar should definitely look into that.

Also gave VSKYLABS' R66 another try. Not sure if it's the added mass or some different ACF file setup, but its handling is more benign compared to the R22, especially in the yaw axis. When mentally taking downwash and vortex rings into account while taking off and landing, it's fairly easy to fly. I've managed to land it on a helipad just fine, sometimes even almost on the "H". But still, it easily slips from intended behavior when losing concentration.

 

 

 

[Matchstick 1,902]

10 hours ago, Bjoern said:

Also gave VSKYLABS' R66 another try. Not sure if it's the added mass or some different ACF file setup, but its handling is more benign compared to the R22, especially in the yaw axis. When mentally taking downwash and vortex rings into account while taking off and landing, it's fairly easy to fly. I've managed to land it on a helipad just fine, sometimes even almost on the "H". But still, it easily slips from intended behavior when losing concentration.

IME bigger, heavier helicopters are almost always FAR easier to handle than the smaller ones you're expected to train with.

Honestly if you can get over the complexity of the cockpit I'm not sure something like the X-Trident B412 isn't the easiest place for a complete beginner to start.

[Bjoern 1,158]

21 minutes ago, Matchstick said:

Honestly if you can get over the complexity of the cockpit I'm not sure something like the X-Trident B412 isn't the easiest place for a complete beginner to start.

Cockpit complexity principally isn't an issue, but at the moment, I'm more focused on a quick startup sequence, good outside visbility and little other potential distractions in terms of systems to completely focus on flying.

I've looked at some freeware and payware helos already, but nothing really struck my fancy yet for various reasons (price, visuals, FPS). Maybe during the next sale. And I'm open to payware recommendations as long as they're not using SASL and have minimum FPS impact.

 

The freeware EC-145 was kind of perfect in XP11 for me, but sadly has not been updated to XP12.

[Matchstick 1,902]

have you tried the XP12 Rotorsim EC135 ?

The internals don't look great and the co-pilot/passenger models are terrible bordering on horrific, but once you turn those off off it's a really good simulation ?

It's also free, though with the option to upgrade to a paid version if you want to support the devs and get a few minor features.

Edited September 13, 2023 by Matchstick

[Bjoern 1,158]

3 hours ago, Matchstick said:

have you tried the XP12 Rotorsim EC135 ?

The internals don't look great and the co-pilot/passenger models are terrible bordering on horrific, but once you turn those off off it's a really good simulation ?

It's also free, though with the option to upgrade to a paid version if you want to support the devs and get a few minor features.

Yeah, just gave the latest version a try yesterday. Good model and the human models definitely need some smoothing applied in Blender. For some reason, however, it eats 20 FPS without any indication as to why (it isn't the plugin) and that's why I uninstalled it again.

[Matchstick 1,902]

5 hours ago, Bjoern said:

Yeah, just gave the latest version a try yesterday. Good model and the human models definitely need some smoothing applied in Blender. For some reason, however, it eats 20 FPS without any indication as to why (it isn't the plugin) and that's why I uninstalled it again.

That's not good. I've not seen that issue myself but XP can unfortunately do that 😞

Of the other XP12 friendly freeware helos the Bel Oh-58 Kiowa Warrior is impressive but complex and the Virtavia Westland Sea King/Commando do show their age but I like them (but that may be because I saw them every day as kid growing up near RNAS Culdrose 😉 )

The XP11 Bell 429 also seemed to be working Ok but I haven't tested it extensively so can't swear to that.

Apart from than that the other quality XP12 helos I can think of are payware and if performance might be an issue that can end up an expensive digital paperweight 😞

[mSparks 2,094]

On 9/13/2023 at 12:41 AM, Bjoern said:

"Left skid low" is a great tip. Adding a bit of left cyclic before lifting off, combined with the preemptive application of some left pedal makes taking off in the R22 easier.

yes, there are lots of "spot on" little but important details in X-Plane helicopters (now), that is one of them.

On 9/13/2023 at 12:41 AM, Bjoern said:

The "bump" after liftoff is still throwing me off a bit and as it happens also when landing, I haven't managed a clean touchdown yet.

The governor behaviour is definitely weird, with lots of overshoots when increasing throttle and an inexplicable sudden decrease in manifold pressure in the first third of the axis range. Laminar should definitely look into that.

So I had another stab at it.

https://github.com/mSparks43/R22_governor/releases/tag/v1

My conclusion is that default is far to aggressive in attempting to maintain rotor rpm, there should be a lot more "slack" in the rotor rpm range and the governor should move the throttle much more graciously. I went back to the maintenance manuals:

--maintainance manual at https://robinsonheli.com/wp-content/uploads/2022/12/r22_mm_book.pdf
    --[[
        Verify throttle correlation. Set MAP to 22 inches and turn governor off. Without
        twisting throttle, lower collective to 12 inches MAP then raise it to 22.5 inches
        MAP. RPM must stay in green arc (Page 1.9)
    ]]

They got this much right, but then the rate they run throttle changes with the governor on is basically "lock rotor rpm at 53 rads/sec", I watched it spin the throttle from 50% to 100% in a fraction of a second at times - that's the "bump".

I instead wrapped it in a dual speed governor that very gently changes the throttle if it goes outside 52.6 - 53.4 and more aggressively if it goes outside 52 - 54 and the prop speed is still going in the wrong direction.

Now to do exactly the same for VSLs R44.

Edited September 14, 2023 by mSparks

[Murmur 3,944]

4 hours ago, mSparks said:

I instead wrapped it in a dual speed governor that very gently changes the throttle if it goes outside 52.6 - 53.4 and more aggressively if it goes outside 52 - 54 and the prop speed is still going in the wrong direction.

Sounds like a classic PID controller could be perfect for the task (or maybe even a simpler PD controller), maybe it can be easily coded in your plugin.