MSFS 2024 Helicopter Turn Coordinators and Slip-Skid Indicators are Inaccurate

Bug Reporting Hub Aircraft & Systems
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ISSUE DESCRIPTION

Description of the issue: On helicopters, the turn coordinators and slip-skid indicators do not read accurately. They do not agree with the yaw string. This is not a problem in MSFS 2020. Please see the attached screenshot showing that the yaw string is centered or showing a slight right bias but the slip-skid indicator shows a full left bias. It is impossible to center the slip-skid indicator on helicopters in MSFS 2024 in normal flight.

In trim
In trim1798×1201 186 KB

If applicable, which aircraft is experiencing this issue: All helicopters.

[PC Only] Did you remove all your community mods/add-ons? If yes, are you still experiencing the issue? Yes.

FREQUENCY OF ISSUE

How often does this occur for you (Example: Just once, every time on sim load, intermittently)? Every flight.

REPRODUCTION STEPS

Please list clear steps you took in order to help our test team reproduce the same issue:

  1. Load MSFS 2024
  2. Select any helicopter
  3. Fly

YOUR SETTINGS

If the issue still occurs with no mods and add-ons, please continue to report your issue. If not, please move this post to the User Support Hub.

What peripherals are you using, if relevant: This issue occurs with any peripherals. I use Virpil ACE Rudder Pedals.

[PC Only] Are you using Developer Mode or have you made any changes to it? No.

[PC, MSFS 2020 Only] Are you using DX11 or DX12? N/A DX 12 in MSFS 2024.

[PC Only] What GPU (Graphics Card) do you use? RTX4090.

[PC Only] What other relevant PC specs can you share? This issue does not depend on specs.

MEDIA

Please add a screenshot or video of the issue occurring.

[END OF FIRST USER REPORT]

:loudspeaker: For anyone who wants to contribute on this issue, Click on the button below to use this template:

Do you have the same issue if you follow the OP’s steps to reproduce it?
•

Provide extra information to complete the original description of the issue:
•

If relevant, provide additional screenshots/video:
•

3 Likes
2

Do you have the same issue if you follow the OP’s steps to reproduce it?
• Yes

Provide extra information to complete the original description of the issue:
• Consistent with the G2. Slip indicator is stuck on the right side of the instrument. I suspect it might be an issue about having it’s internal value centered around 1.0 rather 0.0 something along those lines. It’s like it centers around half way to the right.
If relevant, provide additional screenshots/video:
•

4

Thank you for the bug report.

We have created an internal ticket to see if our team already has this logged, and if not they will attempt to reproduce the issue and create a new bug report. This item is now marked as feedback-logged. If there is an existing bug report or one is created, we will move this thread to bug-logged.

2 Likes
5

This is happening for me too. I can be flying absolutely straight and level down the centreline of the runway on takeoff in the G2 at 50kts before rotation, and the coordination ball will be way, way off centre. Ditto in flight, where if I work to keep the ball centred, I’m applying a massive amount of right pedal and visually am blatantly skidding through the air. The coordination ball is straight up just not telling the truth.

6

Do you have the same issue if you follow the OP’s steps to reproduce it?
• yes

7

Same issue, the ball is always stuck to the right, especially pronounced in the h125 but happening on all helicopters I’ve tried.

8

I see the same in the H125 and R66 which I fly.

1 Like
9

Do you have the same issue if you follow the OP’s steps to reproduce it?
• Yes

Provide extra information to complete the original description of the issue:
• Consistent across all helicopter models. Confirmed not a parallax issue by translating cockpit view to center.

10

As a VR user, I have noticed that some times, after going in and out of VR, the turn slip indicator is fixed in non-VR, but then breaks again in VR until you exit and leave the flight.

11

Confirming. Also the ball is always to the right no matter the slip/skid direction.

12

Do you have the same issue if you follow the OP’s steps to reproduce it?
• Yes, occurs on all helicopters on Xbox Series X

Provide extra information to complete the original description of the issue:
• Why hasn’t this been upgraded to a bug- logged yet? This should be top priority and should have been fixed in SU1. All helicopters are impossible to fly in straight and level flight currently. The yaw string is too unrrliable and buggy as well.

If relevant, provide additional screenshots/video:
•

13

Mostly likely that the 34 votes it has is not enough to flag dev staff to put it into bug logged.

I stream helicopter flight exclusively, and will be trying to get more people to vote on this though

Helicopters are a small subset of the flight sim user base, and they are likely prioritizing ones that have more votes.

14

Do you have the same issue if you follow the OP’s steps to reproduce it?
• yes! Fresh PC, fresh install in 05/25

Provide extra information to complete the original description of the issue:
• the yaw string is working, but this one should be the second choise not the first.

If relevant, provide additional screenshots/video:
•

15

For the Devs, do we need anything more to get this moved along?

2 Likes
16

Do you have the same issue if you follow the OP’s steps to reproduce it?
• Yes, in Cabri G2

Provide extra information to complete the original description of the issue:
• Yaw String seems correct, Turn Coordinator Ball seems wrong, based on flight along runway lines.

If relevant, provide additional screenshots/video:
•

17

Found this post trying to find a fix. So, at least I know it’s not just me.

18

Is this an actual bug? Maybe someone with real helicopter experience can tune in? @belatu42

I think this might be a similar situation as a multi-engine aircraft with an engine failure where the moments are balanced (ball centered) but the forces are not (sideslip).

On a ME aircraft you’ll need to hold 5 degrees bank with ball half displaced towards the operating engine for zero sideslip. No idea if there is a similar trick to achieve zero sideslip on a helicopter.

On a multi-engine aircraft with an engine failure, this force misbalance comes from rudder displacement to counter the yaw, a helictopter has a constant force from it’s tailrotor (hence my theory that it results in a similar situation).

Translation: with the the ball centered the aircraft is not in a zero sideslip situation (as indicated by yaw string), which would be correct behavior.

Edit: From what I could quickly find this seems to be correct and realistic behavior:

“With a tail rotor, the helicopter experiences inherent sideslip (the same as TR drift but in forward flight) so the fuselage doesn’t travel along its centre-line with ‘wings’ level (level on the AI), it drifts slightly to the left or right depending on the MR direction rotation and therefore the anti-torque thrust direction from the TR.

The string will give a reasonably accurate indication of the relative airflow over the fuselage and is often preferred in the slower speed bracket whilst the balance ball will give an indication of skid in the turn but will only remain central on a constant heading if there is a little opposite bank applied to counter the inherent sideslip.”

19

Those are good explanations.

I recently commented on this topic in another thread. The biggest difference from fixed wing, single or ME, is that you’re not flying a wing. You are flying a rotating airfoil that creates a disk. You are also flying the fuselage, slung below the disk that has a vertical rotor on the tail. They are affected by the airstream differently.

The tail rotor actually becomes unloaded when you have enough airspeed for the stabilizers on the tail to become effective. The airspeeds that this occurs depends on the design of the stabilizers. In Robinsons, you will actually have neutral pedals around 45-50knts and have some right pedal above those speeds. The tail rotor also goes through ETL and at low speeds can be affected by the downwash of the main rotor.

The other factor to keep in mind, is that the ball indicates lateral acceleration/inertia. The centrifugal force of the slip or skid accelerates the ball opposite the skid direction.

A helicopter ‘fuselage’ may be in what a FW pilot would consider a sideslip when all of the centripetal forces are cancelled out and the ball is centered. The thrust vector and lift vector are the same in helicopters. So they don’t exactly slip or skid like an airplane. It’s about aligning the fuselage to the thrust vector and direction of travel of the disk in the airstream.

It doesn’t help that the skid ball in MSFS20/24 isn’t represented accurately in all of the helicopters in the game.

20

Whether the main rotor torque is cancelled by tail-rotor or vertical stabilizers, the result (in my mind) should be the same, the moments are balanced (nose is pointing in the same direction - no yaw), but the forces aren’t, therefore there is some sideslip, even with a centered slip indicator.

When the slip indicator is centered on a real helicopter, would the sideslip angle be zero? How do you operate a real helicopter? Do you center the slip indicator and accept that there is some sideslip or would you use a small bank during flight as during hover?

I think the situation is quite similar to an engine failure on a multi-engine aircraft where the asymmetric thrust and drag causes yaw (like main rotor torque causing yaw), therefore continuous rudder displacement is needed to counter the yaw (like tail-rotor anti-torque), the result is that the moments are balanced (no yaw) but the forces are not (sideslip).

Therefore something like 5 degrees of bank towards the operating engine is required with the ball displaced halfway towards the operating engine side to achieve zero sideslip. Therefore a helicopter slipping with a centered ball doesn’t sound like a bug to me, whether it is represented realistically or the magnitude is all wrong, that I cannot answer.

21

What is cancelling the torque makes a difference in helicopters.

In a hover, you will have anywhere from 3-6° bank in the direction of the power pedal to compensate for translating tendency. Cancelling out the torque in a hover requires more power pedal than cruise and causes the helicopter to translate sideways, opposite the direction of pedal input, which must be cancelled out with the cyclic. The sideways thrust of the tail rotor causes the helicopter to hover “skid low” to whatever side the power pedal is. In CCW(most US helicopters) the left skid will be lower than the right during a stable hover.

As you increase airspeed and the torque switches from being cancelled by the tail rotor to the stabilizers, you no longer have to counter the translating tendency because the tail rotor isn’t pushing you sideways. Helicopter tail rotors have more degrees of positive pitch. Neutral pedals doesn’t equal neutral thrust. The first 1/4 of travel(approx.) doesn’t give opposite thrust, it just reduces the amount of thrust. So in a Robinson, for example, the tail rotor thrust is neutral with 1/4 right pedal input. If in a hover, with neutral tail rotor thrust you would no longer be slightly banked, but you would be spinning to the right.

Once you are cruising and the tail rotor is unloaded, you no longer have to bank to compensate for the translating tendency. How much sideslip is occurring to be in trim depends on wind conditions and direction of travel. Yes, the fuselage may be perceived as side slipping with the trim ball centered. The trim ball is centered when the centripetal acceleration is cancelled. Not when the fuselage is traveling straight with the direction of travel.