Mk2 bicoupler causes asymmetrical thrust in ramjets (bug?)

[MechaLynx]

Whenever I make a Mk2 spaceplane using the bicoupler that lets you add 2 engines at the rear, I have an extremely hard time stabilizing it.

It consistently yaws to the left and I tried to figure out what the problem was. I didn't have any asymmetries in the design, but when I checked their thrust during flight, while it was the same between them, the left one was producing less electricity, so I'm assuming its thrust was more unstable.

I added more intakes and it pushes the problem further into the future, but it always ends up happening. I've added the extra engine cooler intake at the rear, before the ramjets and have tried with 3-4 radial intakes per engine but the issue still occurs at both low and high altitudes.

Is this a bug or am I misusing the bicoupler? I haven't had the same problem with multiple ramjets on other craft.

Here's an example of a craft that had this issue:

http://steamcommunity.com/sharedfiles/filedetails/?id=438080906

Edited May 6, 2015 by MechaLynx

[Randazzo]

I know that in 0.90 there was always an issue with asymmetrical air flow to jet engines. Even if you have two engines and two intakes, the intake air was not necessarily divided evenly between them. The manual workaround was to place the intakes meant for one engine, place that engine, then place the intakes meant for the next engine, then place the engine, so on and so forth.

There is a mod out there that balances it for you, but I cannot recall what it was. Very helpful, I know.

[MechaLynx]

The manual workaround was to place the intakes meant for one engine, place that engine, then place the intakes meant for the next engine, then place the engine, so on and so forth.

I don't understand if this is to get around manual errors or how the game prioritizes the intakes or something. I'll try that, not really interesting in going for a mod-based solution just yet.

[Chris_2]

I don't understand if this is to get around manual errors or how the game prioritizes the intakes or something. I'll try that, not really interesting in going for a mod-based solution just yet.

Don't place engines or intakes with symmetry at the same time. Then whats happening:

- Intake 1

- Intake 2

- Engine 1

- Engine 2

So basically engine 1 will take all the intake air it needs, letting engine 2 starve before engine 1.

What you want is:

- Intake 1

- Engine 1

- Intake 2

- Engine 2

So place the engines / intakes manually, or place them together in symmetry (place 1 engine + 1 intake on a nacelle, and then place that nacelle in symmetry).

[MechaLynx]

Don't place engines or intakes with symmetry at the same time. Then whats happening:

- Intake 1

- Intake 2

- Engine 1

- Engine 2

So basically engine 1 will take all the intake air it needs, letting engine 2 starve before engine 1.

What you want is:

- Intake 1

- Engine 1

- Intake 2

- Engine 2

So place the engines / intakes manually, or place them together in symmetry (place 1 engine + 1 intake on a nacelle, and then place that nacelle in symmetry).

Can't say with 100% certainty but this seems to solve the problem. I made a craft with this approach and it didnt suffer any yaw instabilities, then went back and replaced half the parts with symmetry from the others and once air started to get a bit sparse it started yawing to the left again. Strangely, the effect was nowhere near as pronounced with this craft than with others I've made, but at least it seems to be under control for now. I'm marking this as Answered for the time being. Thanks