Props adjusting at different rates in the King Air 350i

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1

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Are you using Developer Mode or made changes in it?

No

Have you disabled/removed all your mods and addons?

No

Brief description of the issue:

Not sure if it is across multiple aircraft or just King Air 350i but occasionally pulling the prop RPM back they pull back asymmetrically. I have the prop increase/decrease bound to two buttons on my joystick so I can control both props with one button for increase and one for decrease. But fairly often when I adjust the props it adjust the left/right at different rates. I believe only when decreasing the RPM every time the right prop lever ends up moving further then the left resulting in asymmetric prop RPM even though the control should adjust them equally.

Not sure what causes it, sometimes they decrease symmetrically other times asymmetrically. When it is asymmetric the right lowers at a faster rate. So as the levers get closer to 0 they become more and more asymmetric.

Provide Screenshot(s)/video(s) of the issue encountered:

image

Detailed steps to reproduce the issue encountered:

Fly King Air 350i and adjust prop levers using the increase/decrease control.

PC specs and/or peripheral set up if relevant:

X

Build Version # when you first started experiencing this issue:

SU11, didn’t play other versions

: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:

2

I confirm, and the same happens on other aircraft dual engine, i.e. the Baron, the new DC-3, etc. .

3

Yep happens on all multi engine props/turboprops. In the sim if you have a general mapping for increase/decrease prop.

Weather third party or not.

1 Like
4

I also correct the difference myself with the mouse. Orz

5

Anyway, I found that the problem solves if you “play” a bit with the props, for example before starting the engines. After seven-ten times, the issue solves itself.

6

I confirm, and the same happens on other aircraft dual engine, i.e. the Baron, the new DC-3, etc. .

Not checked this out thoroughly but think I’ve found a solution to this uneven translation of the prop levers. I changed the respective assignments to “Increase/decrease propeller slow”, which seems to move the levers evenly, while the actual speed doesn’t seem very different and certainly not so slow as to be a problem.

I’ve only tried this with engines running in the DC 3 on the ground but fail to see why it should be different in the air.

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7

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:

Mine was occuring in the Brittain Norman 2 Islander

If relevant, provide additional screenshots/video:

I’ll work on this one.

8

Guys you are my heros. I have been looking for threads that describe this problem. I have only experienced it with the BlackBox Simulation BN-2 Islander. Which I guess they will say is a 3’rd party addon and so irrelavent. But it is so the same problem, with the right propeller moving more than the left. Here is a detailed description of my observations:

If after I takeoff I press Ctrl + F2 to decrease the propeller speed the Right leaver moves a little bit more than the left. If you press can hold Ctrl + F2 there is a small difference. I get the impression that the right lever has gone one step more than the left. However if I do multiple Ctrl + F2 presses the error between the levers gets bigger as though the left is getting one step and the right is getting 2.

There are the odd occasions when this problem does not manifest itself but most of my flights in the Islander are plagued by this problem and are irritating, having to realign the levers with the mouse.

I have not seen this problem with other aircraft – I’ll rephrase that – It does not happen in the DC-3 (The only other piston engined twin-engined aircraft I have).

I would like to say that I can reliably create this problem but actually every now and then it works fine. I have a feeling that it may be associated with doing “Cold and dark” starts but usually on manifests itself after takeoff.

9

Voted. I’ve seen this issue for years now and just wrote it off as me having key bindings messed up. But seeing thread does make me realize…if it’s a key binding problem, it wouldn’t magically go away after some time.

This is definitely a core engine issue.

1 Like
10

Done a bit of testing with FS2020 default aircraft. I only have access to Beachcraft King Air and DC-3 that have twin engines that have propeller levers.

The King Air demonstrates this reliably. You can start is “Cold and dark” or engines running on the end of the runway.

The DC-3 does not display the problem at all (I do note that other people have seen it display the problem in the past).

My BlackBox Simulations BN-2 Islander also displays the problem consistently (“Cold and dark” and engines running on the end of the runway).

I have created a video of the King Air demonstrating the problem: https://youtu.be/PxnwRr0ODAQ

Test conditions:

  • Using Developer Mode: No
  • Disabled/removed all your mods and addons: Yes
  • PC spec: Ryzen 7 7800X3D; 32 GB RAM; RTX 4070 Super 12 GB
  • Build Version # when you first started experiencing this issue: Not sure, about April 2023 when I bought the BN-2 Islander

** Edit 2 Mar 20203 **

I did not find this to be a solution in my testing. The propeller lever movement size is smaller, for each press, but you get the same error builing up with the right lever moving more than the left.

I tried this just after stating a cold and dark start. Use the keybinding to move the propeller levers from - min to max and back to mix - 10 times and still had the problem.

In the past I have had flights where for at least some of the flight the propeller levers moved in sync but this was by far the exception rather than the rule.