Inaccurate Mixture Behavior on Turbocharged Piston Engines

Hi, I just tried for a little bit to get the mod working for the Seneca V but I was having a problem where the aircraft would disappear from the sim and be marked as “Not installed” in the content manager after following the directions in your instruction manual. I actually solved the problem on my own and it works for me now, but others may have an issue.

The issue is with the layout.json file. My layout.json file was way different than the one you provided, so instead of replacing mine with yours, I edited the original file to add the .wasm file, by copying that entry from your layout.json and pasting it into mine. I then made sure the size for the panel.cfg was accurate since I had modified it, and it now works.

I don’t know if this is just a “me” issue or not but hopefully this fix helps.

I’ve got the Arrow bundle, will the install be the same for this package?

Congrats on the work done, and hopefully the devs will fix this in a later update.

I suspect so, but I don’t own the bundle so I am unable to test.

Incredible work! I just bought the Seneca V and have been enjoying it apart from this really obnoxious issue. Can’t wait to try your mod, although Asobo really should just fix this properly already.

Thank you for the feedback, @Synoxys787. To everyone: I’ve created a separate thread for discussing the mod so that this thread can stay dedicated to the bug report and sharing data related to it. Here is a link to the mod thread.

I’ve included a suggestion in the initial post for anyone else who runs into the same problem with the layout.json that Synoxys ran into. If anyone is interested in trying the mod, I encourage you to use the new thread to continue the discussion!

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I’ve tried this on the Turbo Arrow 4, and I’m a little bit confused.

So, the mod seems to work as described, as I climb the lever moves to lean the engine.
My hardware mixture lever does nothing. I can’t lean at cruise, the EGT stays constant depending on throttle setting and rpm. Is this correct and expected behaviour?

Also, is it correct that I have to keep opening the throttle to keep my manifold pressure constant as I climb? I’m a car guy and I’d expect the wastegate to keep closing to keep the manifold pressure constant in a turbo setup. Planes might work differently.

Hmm…you should be able to lean the mixture with your hardware lever at any time. The cockpit lever will move to keep the core-sim mixture set at a level that corresponds to the mixture percentage on your hardware axis, but if you move your hardware lever, the code will react by setting the core sim mixture to match it. Any chance that you have automixture enabled in the sim settings?

The real-life turbo arrow has a fixed wastegate. It requires adjusting the throttle throughout the climb because the wastegate doesn’t move. Basically, it was a way for Piper to offer more power at a low price compared to the competition. Most turbocharged planes have a variable wastegate that keeps manifold pressure constant, like you described. The turbo arrow is quirky in that respect.

I’d be happy to continue discussing on the mod thread (linked below) so we can avoid cluttering this bug report thread with mod details.

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I’m glad I stumbled across this topic. I’m grabbing the files now. This has irked me ever since I got the Turbo Arrow’s and Seneca. Asobo really needs to look into this as is a rather large oversight of a core system on how the engines work.

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This topic has definitely been unnoticed by so many. This is a very important issue.

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Hello WxMarc,

We investigated in this, but the issue raised is based on a feature that doesn’t yet exist on the SIM. Right now, we don’t have default Turbocharged aircraft and changing the setting on the Cfg file can’t result in activating it.

The Turbocharge line in the Cfg file is an heritage of FSX, this is why this line is displayed.

Instead of a bug, this thread should be turned into a request on the wishlist section to add a Turbocharged feature for specific planes.

I’m letting you read the information above before doing any change on the thread.

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Thank you for investigating and providing feedback. I’m a bit confused, though. The turbocharged line in the engines.cfg file definitely has an effect. As such, I’m not sure what you mean by saying that changing the setting “can’t result in activating it.” If turbocharged = 0 in the cfg file, the engine will lose power with altitude like a naturally-aspirated engine should, and no adjustment to the mixture will restore the engine to full sea-level power. On the other hand, if turbocharged = 1, the engine is capable of producing full sea-level power as long as the mixture is adjusted. This is not correct behavior (the mixture should not require adjustment to maintain power in a turbocharged engine), but it is different than the default behavior when turbocharged = 0. To me, this seems like a bug rather than a requested new feature.

If the team would prefer to scrap the old FSX turbocharger logic and start from scratch, I would support making this a wishlist item, but I just want to clarify that the existing logic does have an effect, and the data I’ve reported in this thread documents the bug in the existing logic.

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Should we take this statement to mean that turbocharged aircraft are not supported by MSFS? That is, 3rd party devs should write custom code for the engine logic?

Anyway, isn’t the PC-6 coming to MSFS as part of the GOTY edition? As this has a turbocharged engine, does that mean that turbochargers are supported from SU7/GOTY onwards? :crossed_fingers:

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The PC-6 is a turboprop (gas turbine engine with propeller), not a turbocharged piston. So, the PC-6 would not be affected by the turbocharger logic issue documented in this thread.

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Sorry, my bad.

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For those that are unsure of the difference between turbocharged and a turbo prop - a good video on the PT6A reverse flow dual shaft free turbine engine common in turbo prop aircraft like the PC6.

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In addition to WxMarc’s response, I would note that your third-party partners are under the impression that the turbocharged=1 setting has an effect, since it’s used on Marketplace aircraft such as the Carenado Seneca V (among others). If the official stance of the development team is that the setting does nothing and is unsupported, this should be communicated to the third-party partners more clearly so they know not to use it.

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eh, well the GOTY edition has the p51… that turbocharged so you DO now have default turbocharged piston aircraft… time to revisit this.

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Bumping this for appearance.

Asobo, you now have two default aircraft in the sim, the T6 Texan and P51 which are TS engines, as well as multiple other Turbo aircraft coming in as payware (To my knowledge, C182T, M20R, C337 (unsure of exact variant some were TSIO engines), PA34T, PA28R Turbo, C414A, and many others soon to come) which are all flawed on the basic principle of their operation.

In my eyes this is no longer an ignorable system deficiency and needs to be addressed for the overall well-being of the sim. Asobo, do you really expect us to be at cruise altitude with our mixture levers teetering between flooding the engine, normal operation, and fuel starvation?

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BIG BUMB!

This is important ASOSBO and MS! We count on you here!!!

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