check procedures the rudder trim overeact during takeoff(instant trim setting)

[Ddg1500]

Hello, recently i feel that the rudder trim is much better improved, with much less "overeaction" in many situation, this include low speed hover, cruise etc, those improvement make flying apache much more comfortable

However, there is still some situation that still cause rudder trim overreaction.

Like during transition from curise to hover close to the ground, the rudder trim would still overreact significantly that could shift the nose to another direction dangerously.

the rudder trim and cyclic trim performs comfortably well, expect at this situation.

Here is my track file

TrIm test transition.miz

[Ddg1500]

Hello,i'm fervently grateful of the correction of trim overeact problem during transition, hover and other situation, thank you

i have done at least 4 test recently, each lasting at least 1.5hrs to test the trim especially rudder trim at different state.

There is still a salient trim overreaction during take off, just after the wheel leaves the ground with collective increasing, it's at this state that there would need a immeidate and massive rudder trim to counter and correct the turn force of the main rotor due to increased rpm, the rudder trim would overeact significantly, and its troubling.

Also, i hope there is also a more comprehesive and general review about the trim behaviours (both cyclic and rudder) at different state of ah64, i wish it could be more comfortable and safe to use.

Real life heli pilots don't have such issue as their controls will be remembered in position right after the press the trim button, and they trim highly frequently, with their trim don't result in overeaction unless they intent. The dcs guys, however, rarely have that luxury, so the trim mechanism need to be well tuned to the spring loaded device.

Here is my track file

TrIm test takeoff.miz

[Raven (Elysian Angel)]

Why would you create 3 threads on the exact same topic?

You’re aware that you can just reply to an existing thread, right? Less bloat that way, and easier to find relevant information.

 

 

 

Simply reply to the existing thread here:

@NineLine Perhaps these threads can all be merged? Thanks!

Edited June 30 by Raven (Elysian Angel)

[Ddg1500]

Got it,there is still some rudder trim overeaction during transition, occasionally during rapid change from crusie to hover, the rudder trim during transition still need some work

[bradmick]

If you’re relying on the yaw SAS to keep you stable transitioning from forward flight to a hover and vice versa, you’re doing it wrong. The system does not have the authority to keep the nose where you would like it to be, and it’s not designed for that. It is not an auto pilot, the proper procedure whenever you’re making large changes to airspeed, power, altitude, etc is to hold the force trim interrupted and *fly* the helicopter. Real pilots have crashed perfectly good helicopters because they relied on the automation (which they didn’t understand couldn’t do what they wanted/expected) rather than just…flying the helicopter. 
 

Yes. There are known issues with excessive torque, but your issue is specific to failing to fly the aircraft and interact with the flight controls as they’re intended to be used.

[Ddg1500]

2025/7/1 PM6点48分，bradmick说：

If you’re relying on the yaw SAS to keep you stable transitioning from forward flight to a hover and vice versa, you’re doing it wrong. The system does not have the authority to keep the nose where you would like it to be, and it’s not designed for that. It is not an auto pilot, the proper procedure whenever you’re making large changes to airspeed, power, altitude, etc is to hold the force trim interrupted and *fly* the helicopter. Real pilots have crashed perfectly good helicopters because they relied on the automation (which they didn’t understand couldn’t do what they wanted/expected) rather than just…flying the helicopter. 
 

Yes. There are known issues with excessive torque, but your issue is specific to failing to fly the aircraft and interact with the flight controls as they’re intended to be used.

Thank you, i don't know there isn't SAS ofduring transition, There is still some rudder trim problem during ground taxing, other part its been much better

ground taxi trim 2.miz ground taxi trim.miz

[Ddg1500]

2025/7/1 PM6点48分，bradmick说：

If you’re relying on the yaw SAS to keep you stable transitioning from forward flight to a hover and vice versa, you’re doing it wrong. The system does not have the authority to keep the nose where you would like it to be, and it’s not designed for that. It is not an auto pilot, the proper procedure whenever you’re making large changes to airspeed, power, altitude, etc is to hold the force trim interrupted and *fly* the helicopter. Real pilots have crashed perfectly good helicopters because they relied on the automation (which they didn’t understand couldn’t do what they wanted/expected) rather than just…flying the helicopter. 
 

Yes. There are known issues with excessive torque, but your issue is specific to failing to fly the aircraft and interact with the flight controls as they’re intended to be used.

 

3.miz

[Ddg1500]

2025/7/1 PM6点48分，bradmick说：

If you’re relying on the yaw SAS to keep you stable transitioning from forward flight to a hover and vice versa, you’re doing it wrong. The system does not have the authority to keep the nose where you would like it to be, and it’s not designed for that. It is not an auto pilot, the proper procedure whenever you’re making large changes to airspeed, power, altitude, etc is to hold the force trim interrupted and *fly* the helicopter. Real pilots have crashed perfectly good helicopters because they relied on the automation (which they didn’t understand couldn’t do what they wanted/expected) rather than just…flying the helicopter. 
 

Yes. There are known issues with excessive torque, but your issue is specific to failing to fly the aircraft and interact with the flight controls as they’re intended to be used.

There is stil some rudder trim problem during ground taxi, and i don't rely on SAS to fly the aircraft, could you take a look?

[BIGNEWY]

We are not seeing any problem with the rudder trim sorry. 

please save track (.trk) replays and not (.miz) missions if you are trying to show us something. 

thank you 

 

[Ddg1500]

47分钟前，BIGNEWY说：

We are not seeing any problem with the rudder trim sorry. 

please save track (.trk) replays and not (.miz) missions if you are trying to show us something. 

thank you 

 

Here is it, do you see the overreaction after rudder trim during taxing on the ground , or the oversteer during rapid reduction in rpm( and is also corrected by rudder trim yet it still overeact due to rapid reudction in torque)

and i know that when "tailwheel unlock" is selected the apache would be very sensitive in yaw and need to be immedately trim after increasing collective, and I flew dcs mi24(which also have a road wheel) or huey(which don't have a rudder trim) without encountering any of the issue of apache on ground taxi trim, those two helio performs comfortably nice on trim(espeically mi24) on any situation(transistion, hovering taxing etc), where apache would just like to over yaw or steer after rudder trim.

which is probably due a not well tuned algorithm that set the center of the rudder after trim excessively left or right that ultimately keep it oversteer during taxing, real helicopter use a mechanical system to keep the new trimed rudder position as the new center, whereas in dcs, many players use only spring loaded rudder with no damper, as a result, using a algorithm to tune and compenate to simulate the rudder trim was produced, and that's where the problem is.

i know that the ED Beta Tester say it is my perosnal issue of control and understanding of aircraft that lead to this problem, which i respectfully disagree, and before having a sudden fervent passion on apache, i have flew mi24 for a considerable while, while using both "instant trim(ffb friendly) setting on both cyclic and rudder using full virpil base and rudder(spring loaded no ffb no damper) , the rudder trim(or both trim) never overeact and was right on spot.

I have realized that many of my previous post on this issue has been worked and i am very grateful, but there is still some loose end left, I will continue to accmulate my experience on ah64, and i hope issue can be solved. 

rudder trim taxi 3.miz rudder trim.miz taxi rudder trim .miz Rudder trim taxi 4.miz

[BIGNEWY]

Hi, 

you seem to be saving missions and not tracks. 

After you exit the mission during the debrief select save track.  

[bradmick]

I believe the CAS is still active while ground taxiing which causes the yaw axis to be overly sensitive. The yaw CAS is supposed to be disabled while ground taxiing to prevent over steering. It’s been a known issue that the yaw axis is overly sensitive during ground taxi.
 

The other part of the issue is the excessive main rotor torque issue that’s been around since release. The fm is still WIP. 

Edited July 17 by bradmick

[Rogue Trooper]

Hi Ddg1500,

You understand that for taxiing, you are comparing aircraft that have nose wheel steering (Hind, MI-8, KA-50) to aircraft that are have tail wheel (castor) steering (Apache).

You do get that these are very different ways of controlling an aircraft on the ground... yes?

You understand that the steering mechanism of a nose wheel (hydraulically driven) is just in front of the  pilot and reacts quickly to pilot input. The Apache has a castor tail wheel (free floating, unpowered) and is many meters behind the pilot and these many meters amplify the power coming from the tail rotor thrust.... you get that? 

You understand that they designed it this way to allow for the installation of the downward looking, free floating, 30mm cannon close to the centre of gravity of the airframe....Yes?

For me these are obvious, indeed massive contrasts of helicopter ground control and must be modelled in DCS!.

You simply have to work harder and sort it out.

 

Edited July 17 by Rogue Trooper

[Rogue Trooper]

When you get to grips with the Apache you will be ready for our UH-60 Blackhawk and maybe in the very long future, the MI-28.

Out of interest, our blackhawk will be older with steam guages and older SCAS, but will have the cranked tail rotor, meaning when you push the tail rotor left or right it will also push the nose up or down.... fantastic!

Nothing is easy in DCS!

 

Edited July 17 by Rogue Trooper

[admiki]

Great points, except both Mi-8 and 24 have castoring nosewheel, don't know about KA-50.

Edited July 17 by admiki

[Rogue Trooper]

Good point, KA-50 is probably the same except its rotational turn is around the the centre of gravity (main coaxial rotors).

Which leaves the centre of turn point for the hind and MI-8 roughly around the main left/right wheels, do you agree admiki?

Where is the Apache's centre of turn, is it closer to the tail? 

Edited Thursday at 08:39 PM by Rogue Trooper

[Cyborg71]

Ooooh, Blackhawk confirmation.

[Rogue Trooper]

1 minute ago, Cyborg71 said:

Ooooh, Blackhawk confirmation.

Cranked tail rotor and all!

 

Edited July 17 by Rogue Trooper

[Raven (Elysian Angel)]

2 hours ago, Rogue Trooper said:

Out of interest, our blackhawk will be older with steam guages and older SCAS

Where did you hear that? Last time I checked, ED said they have enough data for a UH-60L but were waiting for more information to do an -M.
I actually would prefer an -L though, so if that's the one we'll get I'm a happy bunny!

[Rogue Trooper]

From the Wags' mouth: actual. It will not be a MFD laden airframe.

Personally I would have Liked the UH-60 to be on par with the Chinook as their MFDs are the same. But an earlier bird with a a lower SCAS system in an older airframe, with a cranked tail rotor would indeed be a fantastic thing in DCS!...... probably not for the DEVS. 

Hopefully I am not hearing what I want to hear but basically this will be the only cranked tail rotor chopper in DCS.

Edited Thursday at 08:22 PM by Rogue Trooper

[MAXsenna]

Great points, except both Mi-8 and 24 have castoring nosewheel, don't know about KA-50.

Castoring, at least in the sim.

Sent from my SM-A536B using Tapatalk

[Rogue Trooper]

2 hours ago, admiki said:

Great points, except both Mi-8 and 24 have castoring nosewheel, don't know about KA-50.

What is your take on the front nose castor wheel and the tail castor wheel admiki?

Do you think a tail castor is harder to steer than a nose castor?

[Raven (Elysian Angel)]

2 hours ago, Rogue Trooper said:

this will be the only cranked tail rotor chopper in DCS

Yes and I am excited about that: more variety and different handling to get used to. The -L uses a pull - tail rotor as far as I understand, to help with CoG but with the downside of yaw/pitch coupling.

[admiki]

8 hours ago, MAXsenna said:

Castoring, at least in the sim.

Sent from my SM-A536B using Tapatalk
 

I can confirm that for the Mi-8 IRL. Maybe -17 or -171 got steering, but I'm not aware of it. 

7 hours ago, Rogue Trooper said:

What is your take on the front nose castor wheel and the tail castor wheel admiki?

Do you think a tail castor is harder to steer than a nose castor?

If we are talking about airplanes, front wheel is more stable, I fly both.

For helicopters? I don't think there is much difference, since you have torque and tailrotor to contend with in the first place.

[Ddg1500]

2025/7/16 PM6点45分，BIGNEWY说：

Hi, 

you seem to be saving missions and not tracks. 

After you exit the mission during the debrief select save track.  

Here, sorry for my mistake as i been raw on track file, please notice the excessive steer after rudder trim during taxing and increasing & reducing collective, which is due to a inadquately tuned rudder trim model that set the new center of the rudder excessive to the torque that casue it to continously over steer, furthermore, all my rudder trim performed  in the track file is intended to hold the aircraft straight, i pick a rudder spot that I feel is right to keep the apache  straight intead of oversteer, compenating the twisting force of torque，yet when I trimmed the rudder, the apache always oversteer, and  that where the problem is, as i don't encounter any of those issue on mi24

Ground taxi trim 1.trk Ground taxi trim 2.trk Ground taxi trim 3.trk

Edited Friday at 05:54 AM by Ddg1500