Force Trim

[deloy]

Although I cant say for Apache (I have real world experience in some other military helicopters), I do feel that SCAS needs some fine tuning specially in high speed ranges, it tends to be somewhat unstable in roll.

[Dallas88B]

Do contributors to this thread find the patch DCS 2.7.15.26783 Open Beta - 22.06.2022 improved SCAS behavior? and is the Central Position Trimmer Mode workable now? DCS 2.7.15.25026 Open Beta - 08.06.2022

Is hovering as manageable as it should be? Just trying to figure out if the challenge to keep the Apache stable especially at hover is just me.

 

[Hammer1-1]

1 hour ago, Dallas88B said:

Do contributors to this thread find the patch DCS 2.7.15.26783 Open Beta - 22.06.2022 improved SCAS behavior? and is the Central Position Trimmer Mode workable now? DCS 2.7.15.25026 Open Beta - 08.06.2022

Is hovering as manageable as it should be? Just trying to figure out if the challenge to keep the Apache stable especially at hover is just me.

 

well each option has its own quirks, so its going to be whatevever you like the best out of the options. However, it hovers just fine and rock solid if you trim it up right and hit the altitude and heading hold.

[Raptor9]

1 hour ago, Dallas88B said:

Is hovering as manageable as it should be? Just trying to figure out if the challenge to keep the Apache stable especially at hover is just me.

It's certainly manageable in my view, but I've been flying DCS helos for over ten years, so I'm used to the trimming system and how it simulates real-world force trim behavior. The two biggest things to understand is that:
1) Most times you need to press the force trim release switch at least twice; once to set the new trim position, and then one more to fine tune it ever so slightly. This is pretty much how it is in real life as well.
2) Hold modes are not autopilot. They are designed to hold your trimmed state. So if you want them to be effective, you need to be able to force trim the aircraft to a stable flight condition, whatever that may be, and then engage the hold mode.

I'm not a member of the dev team and don't speak for them, but I will say the flight model and Flight Management computer are still WIP, and I imagine they will continue to evolve during early access. However, in the next update to the manual, there should be a new section that goes into detail about how the FMC and hold modes work and their associated control logic.

[Dallas88B]

With the Apache in forward flight it seems OK but transitioning to hover or to land remains, for me, pretty problematic. Sometimes its OK and other times it suddenly lurches off to one side. No apparent reason I can discern, its a basic test mission, light load, no wind or turbulence. Far as I can tell I am not doing anything different. Anyway, as you say @Raptor9 flight model and flight management is still WIP. I guess I am WIP too. Maybe the experience will get better.

Edited July 15, 2022 by Dallas88B
fixed typo

[mbits]

As far as central trimmer goes I realised a couple of weeks ago that the default ffb friendly option is way better for me.  I thought the fact that mode "doubles up" as you hit force trim would be really bad, but it seems you get a short while to centre before that happens. Now I don't have to put up with the occasional disaster of inputs being ignored because I was busy and didn't centre properly after force trim.

[Raptor9]

7 hours ago, Dallas88B said:

 I guess I am WIP too.

 Aren't we all.

[GrEaSeLiTeNiN]

11 hours ago, Dallas88B said:

Do contributors to this thread find the patch DCS 2.7.15.26783 Open Beta - 22.06.2022 improved SCAS behavior? and is the Central Position Trimmer Mode workable now? DCS 2.7.15.25026 Open Beta - 08.06.2022

Is hovering as manageable as it should be? Just trying to figure out if the challenge to keep the Apache stable especially at hover is just me.

 

Been flying the Ka-50 for a couple of weeks. Probably spoiled by it. I just went back to the Apache (OB latest) to see if the patch made things better. But initial impressions to me are that it is worse than before. Maybe I just need time to get use to it again. But it is certainly the most unstable helo in DCS. I mean roll a little, trim, but it rolls some more. Pitch a little, trim, but it pitches some more. There is just way too much unwanted momentum to any input you make. Feels like I am trying to center a ball on a moving table when hovering.

Edited July 15, 2022 by GrEaSeLiTeNiN

[S. Low]

The question was raised to members of LLH so I’ll restate and add on to my response here, in regards to the current feel of the aircraft. Note I’m not a pilot, just a regular sim dude who tries to fly this aircraft like the pilots tell me to.

i had been using instant trim with a regular spring-in stick and simply dealing with the controls jolt associated with this option. This was getting too aggravating for me during transitions from high speed to slow speed, especially landing. When central trimmer was updated awhile ago I switched. It works great. I hold my control surfaces where they need to be, press trim button once and release immediately, I release my physical controls immediately to return to center, and the general act of trimming works fine and is stable

When I trim the aircraft out it never seems to be as trimmed as it should be. The aircraft still is climbing significantly or drifting left or right yaw. It seems to me a good trim shouldn’t result in this much deviation, but that’s just a guess. 

The excessive crabbing and the uncommanded left roll with forward cyclic input are still present and contribute to the feeling of instability in this flight model.

Now with hold modes activated, using FTR to change the hold mode position does work but it’s very unstable. So to spell it out I’m flying with hold modes, but I want to change the direction  a bit and altitude. Rather than canceling modes and reactivating, you can hold FTR, get a new speed and altitude, then release the FTR button and the modes will keep you there. It works. But when you’re holding FTR it’s like the stability system turns off entirely, not just the hold mode. You go from a fairly stable helicopter to a wobbly mess. But it “works” to a degree. Is this realistic? I dunno. Just commenting.
 

When transitioning to an OGE hover the aircraft behaves fine to my knowledge. But when transitioning to an IGE hover something does change in the aircrafts characteristics and you  become very wobbly. You can regain control of the aircraft and stabilize it with gentle inputs as long as you stay ahead of the sim aircraft, but it’s odd. Further this IGE oddness can be avoided by transitioning to IGE hover at like 10ft, just before landing, and immediately land using the beefier landing gear.

There’s definitely quirks being ironed out. Mostly what I want fixed is the crabbing and left roll.

Edit: had an afterthought. The aircraft feels oddly unstable above 120 knots, like it’s about to start barrel rolling. 

Edited July 15, 2022 by S. Low

[Floyd1212]

1 hour ago, S. Low said:

But when you’re holding FTR it’s like the stability system turns off entirely, not just the hold mode. You go from a fairly stable helicopter to a wobbly mess. But it “works” to a degree.

Yes, this is what I experience as well.  holding the FTR is the best way to ruin your perfectly good hover you were just in, when all you wanted to do is change heading 30 degrees.  I find myself disabling ATT Hold briefly, changing my heading, and then enable it again, hoping I haven't started drifting more than 5 knots in the process.

The other option is to apply slow and steady pedal input until you reach the break-point to where the SAS stops fighting you and starts assisting you, but then you run the risk of not being able to arrest the rotation again at the desired heading.

For me the biggest struggle is still smoothly transitioning to an OGE hover at my desired battle position.  If I'm coming to a stop behind a hill, and I'm trying to keep myself from elevating above the treeline, I'm dancing that fine line between not enough collective to keep me in the air, and just the right amount of collective to maintain my desired altitude.

[dburne]

I am constantly trimming as I am slowing forward flight to transition to a hover. I feed in left pedal and trim the slower I get, cause I know if I don't the chopper is going to yaw to the right significantly. Also as I am transitioning the nose of the chopper will want to lurch up, I arrest that lurch and trim again. Also have to raise the collective some all whilst doing all this to keep the chopper from entering a strong descent.

After more hours than I care to think about I am finally getting to where I can do the above smoothly and enter a hover, and engage ATT and ALT once there. But it is very tricky during the last part of the transition from forward flight to hover and got to really stay on your toes with it.  Now also getting better at landing where I want, after making the transition from forward flight to hover per the above, I engage only ATT to maintain my position over landing spot and slowly lower collective touching down gently. Getting better at this finally as well.

I think I am about ready to enter some SP combat now flying as Pilot that is. I've gotten pretty decent at the live fire weapon range but now need to find out how I can hold up with real enemy AI. Soon I hope.

Edited July 15, 2022 by dburne

[Scaley]

One thing to note is both the yaw and roll channels of the SCAS still "hunt". That is, they don't settle to the desired position they oscillate around the position they are aiming to get to. This gets worse at higher airspeeds. If you fly at 135kts with the control indicator open you'll see the green cross slowly oscillating side to side in roll particularly. I don't know how much that is contributing to the current feeling of instability. 

[GrEaSeLiTeNiN]

On 7/15/2022 at 4:01 PM, mbits said:

As far as central trimmer goes I realised a couple of weeks ago that the default ffb friendly option is way better for me.  I thought the fact that mode "doubles up" as you hit force trim would be really bad, but it seems you get a short while to centre before that happens. Now I don't have to put up with the occasional disaster of inputs being ignored because I was busy and didn't centre properly after force trim.

I have a desktop Warthog and VKB T pedals. After reading your post, I decided to try instant trimmer again for both hotas and pedals. I also drastically changed the axes tuning especially for yaw [Pitch and Yaw = Dead0, X100, Y75, Curve15, Pedals = Dead0, 100X, Y70, Curve 15, Collective = Dead0, X/Y100, Curve15].
Dead0 and instant trimmer gave me quicker response and control, something that's needed with the current state of the Apache. So flying now involves a lot of 'micro' trim tapping and stick centering. Yaw on the pedals was super sensitive so I set it to Y70. For the problematic rolls, Y75 made inputs less sensitive but I retained the ability to roll 360 on demand, not as quickly but enough. Trim to stable hover parameters from speed, then engage ATT hold and ALT hold, and OGE hover is now more doable.

My main problem though is that after all that 'fighting' to hover stably, I often end up facing away from the target’s location and have to apply rudder trim bit by bit to align the aircraft to the target. And sometimes that messes things up. Is there a better way to do this? Update: Found this tutorial. Just what I needed.

There's the usual tussle with and dilemma with SCAS of course. Holding FTR down to bring the + closer to my ◇ and x just means destabilising things and you can end up all over the place. The + also moves back to where it wants to go after you release FTR hold down, so I find FTR hold down kind of pointless or at least I haven't found a right use for it. I could trim to bring my ◇ and x to where the + is to 'agree' with SCAS but that just means status quo and the + may also move again. So far, trim tapping bit by bit seems to be the safest way to go about it. 

The tutorial vids I've been able to find so far only show IGE hover from take-off or a slow approach speed in stable conditions. I have yet to find one demonstrating OGE hover from a higher approach speed and maneuvering to face the target's location in some wind. I guess the procedure would basically be the same but it would show the true nature of SCAS and how to best handle it, albeit a WIP.   

I see the above axes tuning and instant trim option as a workaround. I hope they fix the FM not in the sense that ED feels it's about right and just needs a little tweaking because I can't believe this is how the Apache behaves IRL. Even in logic, it feels off - being roll happy and having excessive momentum with small inputs. 

[updated]

Edited July 19, 2022 by GrEaSeLiTeNiN

[mbits]

That's interesting. I should say I don't use force trim for pedals as mine are springless. Don't know yet if that's something I'll reconsider but I don't feel like I need it on them.  Going to read your settings in more detail next time I fly.

[TZeer]

Note:  I have a springless setup with a damper-mod installed on my VIRPIL pedals. So no re-center of pedals between trim.

I have the same issue with aligning the aircraft while in hover.

I can get into hover quite easily, stable and fine. But when I want to change my direction to get a better firing solution for targets out to either side, it seems the SCAS keeps fighting me.

Pushing the FTR just knocks the aircraft into some unstable mode, and you really have to fight to keep it stable. And this happens regardless of how stable you are before you engage hold modes. I can get it 99%. Small drift but showing 0 knots, stable altitude etc.

Stable hover --> Engage hover --> Engage targets --> Turn left/Right??? How??

What is the correct way to align the chopper left/right a few degrees to improve firing solutions for targets out to the sides?? No matter how I do it, I feel the SCAS is fighting me. And pushing the FTR just makes the whole thing unstable....

[GrEaSeLiTeNiN]

On 7/17/2022 at 4:19 PM, TZeer said:

Note:  I have a springless setup with a damper-mod installed on my VIRPIL pedals. So no re-center of pedals between trim.

I have the same issue with aligning the aircraft while in hover.

I can get into hover quite easily, stable and fine. But when I want to change my direction to get a better firing solution for targets out to either side, it seems the SCAS keeps fighting me.

Pushing the FTR just knocks the aircraft into some unstable mode, and you really have to fight to keep it stable. And this happens regardless of how stable you are before you engage hold modes. I can get it 99%. Small drift but showing 0 knots, stable altitude etc.

Stable hover --> Engage hover --> Engage targets --> Turn left/Right??? How??

What is the correct way to align the chopper left/right a few degrees to improve firing solutions for targets out to the sides?? No matter how I do it, I feel the SCAS is fighting me. And pushing the FTR just makes the whole thing unstable....

This just popped up on my YouTube. Have yet to try it with the current beta. Looks like adding and maintaining pedal a little beyond SCAS authority (>20%?) is one way. The other is trimming if the yaw adjustment required is smaller.

 

Edited July 18, 2022 by GrEaSeLiTeNiN

[TZeer]

But it's still a sort of a workaround to get it done. First one is forcing the apache outside the SCAS authority. And only works on large movements. Second one is "tossing" it in the direction you need and retrim before it goes back. Making the whole thing oscillate until it stabilize in the new direction.

 

Look at this footage of how stable the whole thing is while hovering above ground, and doing two 90 degree turns. There is no sign of any oscillation or anything. But I guess it's a little different, since it's probably not in any hover hold modes.

I could probably try disengaging attitude hold, before applying inputs on the rudders. But will be a challenge if the SCAS has some inputs that needs to be compensated when taking off the attitude hold mode.

Any tips from @Raptor9 or @kgillers3 maybe?  What is the correct way for the Apache Pilot to correct heading while in hover? Do you just push and hold FTR while doing it? Or disengage the hold modes while turning?

Hopefully it will be refined as the FM still is WIP.

 

[Dallas88B]

5 minutes ago, TZeer said:

Look at this footage

Now that is a nice video.

[GrEaSeLiTeNiN]

The tutorial vid looks to be pre ALT hold mode but I believe it is mainly ATT hold that restrains yaw. Then again ALT hold might affect yaw in some way since it works the collective as well and thus the torque? Let’s hear from an SME.

Edited July 17, 2022 by GrEaSeLiTeNiN

[Floyd1212]

I was going to re-post my little tutorial video here, then I scrolled down and it looks like someone already did.

Since posting that vid I find myself more often disabling ATT Hold, making the heading adjustment, then re-enable ATT Hold for larger adjustments, and using the "re-trim" method for minor adjustments.  The "breaking out of SAS" method tends to result in hunting for the right pedal input for the new desired heading as by then the SAS is readjusting how much assistance it is providing anyway.

[kgillers3]

3 hours ago, TZeer said:

But it's still a sort of a workaround to get it done. First one is forcing the apache outside the SCAS authority. And only works on large movements. Second one is "tossing" it in the direction you need and retrim before it goes back. Making the whole thing oscillate until it stabilize in the new direction.

 

Look at this footage of how stable the whole thing is while hovering above ground, and doing two 90 degree turns. There is no sign of any oscillation or anything. But I guess it's a little different, since it's probably not in any hover hold modes.

I could probably try disengaging attitude hold, before applying inputs on the rudders. But will be a challenge if the SCAS has some inputs that needs to be compensated when taking off the attitude hold mode.

Any tips from @Raptor9 or @kgillers3 maybe?  What is the correct way for the Apache Pilot to correct heading while in hover? Do you just push and hold FTR while doing it? Or disengage the hold modes while turning?

Hopefully it will be refined as the FM still is WIP.

 

It’s important to distinguish that due to the differences in the physical controls and the differences between how the game perceives an input versus real life and dcs the two aren’t the same and every setup will vary based on user curves and style of controls. I have springs on my rudders/pedals and I’ve just become accustom to lifting my feet after trimming with a 3% dead zone which allows the pedals to recenter in real life and in game holds whatever trimmed position and I don’t accidentally click off unless I mean to. I use the first option or instant trim I believe it’s called.  I apologize it’s been a long day and you’ve probably said what you’re running but I haven’t seen it. There should be the third option in the special menu which I’m guessing would more benefit your control setup for the pedals, reason is it’s not expecting the pedals to center and it just moves the trim setting. I don’t know if it’ll help but maybe. I’d suggest adding a slight dead zone, and a tad bit of friction so you’re controls don’t drift. Idk if it’ll help it’s worth a shot. As far as holding the trim release, in game I make an input and bump the button when I get it to where I want or the desired input.  I haven’t been able to play the latest update so what I used to do may be different with the latest flight model tweaks.  I hope you find something in this to either give you an idea to make it a more enjoyable experience or at least an idea to go down.  Good luck 

[TZeer]

Appreciate your feedback @kgillers3.

I have a VIRPIL ACE pedal, where I have taken off the spring and installed a damper mod. I have also reduced my deadzone, as I do not need to re-center between trim. Has greatly increased the feeling and ability on the rudders. I am thinking that maybe the best solution for me, as of now, is to disengage ATT Hold, turn to new heading, and engage ATT Hold again.

PS: For anyone looking to do this mod. It's very easy. And no need to move the spacer to the underside as done in the clip. After assembling all parts it took about 10 minutes to install.

Like this one: 

 

Edited July 17, 2022 by TZeer

[Scaley]

59 minutes ago, TZeer said:

Appreciate your feedback @kgillers3.

I have a VIRPIL ACE pedal, where I have taken off the spring and installed a damper mod. I have also reduced my deadzone, as I do not need to re-center between trim. Has greatly increased the feeling and ability on the rudders. I am thinking that maybe the best solution for me, as of now, is to disengage ATT Hold, turn to new heading, and engage ATT Hold again.

 

Same pedal and mod, and same solution. I rarely fight the ATT hold heading hold, just toggle it off and then on again at the new heading. Also I've basically stopped using any kind of "hold the FTR down" technique. It clear that since the DCS 64 disables the most of the SCAS functions when you do that we can't just carry across the real-world techniques. Interestingly it clearly doesn't disable everything, since FTR held down does not produce the same behaviour as switching off the SCAS channels. Hopefully it's all still WIP.

[Raptor9]

3 hours ago, Scaley said:

 I rarely fight the ATT hold heading hold, just toggle it off and then on again at the new heading.

The ATT hold being on or off has no effect on the Heading Hold below 40 knots ground speed. Heading Hold is always enabled in this speed region. Heading hold will disengage from the flight controls if you displace the pedals 3% in the yaw axis or if you press the force trim release, and it won't re-engage again until the the FTR is no longer pressed, the pedals are within 3% of the force trim location, and the yaw rates are less than 3 degrees per second. As a result, if you are using spring-centered pedals with "Instant Trim" option selected for the pedals, it can be difficult to meet this criteria. I use "Instant Trim" on the cyclic but "Central Position" on the pedals, and it works better for me (I have Saitek Rudder Pedals, so take that for what it is worth).

In the next manual update there will be an entire section dedicated to explaining the logic of the FMC, so hopefully that clears things up regarding the various hold modes and force trim interaction with them.

[corbu1]

vor 5 Minuten schrieb Raptor9:

In the next manual update there will be an entire section dedicated to explaining the logic of the FMC, so hopefully that clears things up regarding the various hold modes and force trim interaction with them.

Thank you!!

This is really good news. Looking forward to it…….