Yes they are mostly always oil driven. There are some light aircraft that use an electric system but the 414 does it in the traditional way using oil.
Thanks - but should there be oil pressure following parking up and switching off engines? I was able to rotate them backwards and forwards.
No that should not be possible
No engine, no oil pressure, no prop control. At least that’s how it should be.
Will try again when next on, might be my error, not a big deal, just didn’t fit with logic - ie if electric then battery off, and if hydraulic then no engine.
Doesn’t some pressure remain after the engine is turned off? I’m sure on one plane I was able to take them out of feather once or twice, and then it no longer worked. I don’t remember if that was the 414 though. I got the impression this wasn’t a bug but an attempt to simulate an effect.
That I don’t know. Twins and singles tend to have a different system. I think due to the need for feathering. They use springs, latches etc to control the different requirements.
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Depends on the engine.
Typical light singles are designed to use increased oil pressure to push the prop toward coarse pitch/low RPM (pulling back on the prop lever), which acts against against a spring in the hub piston (and aerodynamic forces) that is trying to push it toward fine pitch/high RPM. So loss of oil pressure will ensure it goes to high RPM. Most singles aren’t designed to feather, though, and there’s a physical stop for both coarse and fine pitch.
In a light twin, it’s backwards of that - increased oil and nitrogen pressure pushes it toward fine pitch/high RPM, so when you lose oil pressure (like with a failed engine), the spring (which is on the opposite side of the hub piston than it is in a single), aerodynamic twisting, and counterweights push the prop toward coarse/low. You still have to pull it all the way back to feather.
However, both types usually have a centrifugal pin called a feather stop, which prevents it from feathering (or going coarse) below a certain RPM. In the Seminole, this is 950 RPM, so if you don’t feather it before it drops below that speed, you might not be able to feather.
It’s part of why we train so much to identify, verify, feather, and secure.
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So in essence you should not be able to move the prop blades when the engines are shut down.
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That’s correct.
You can’t even feather them in the air if they get too slow.
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So it’s a bug not a feature
Unless it’s emulating broken feather/lock pins, then it’s likely a bug (or just not emulated at all).
It’s an odd bug if that’s the case. I wish I could remember the plane I last played with this. It was either the Caravan, or the Kodiak. But after shutdown I was able to feather/unfeather the prop once, and then it didn’t work any more. That felt like simulating oil pressure being lost, but with some movement before that happened.
Prop blades changing pitch per prop-control, while the engine is not running, is a modeling/animation gimmick… as there is no direct-relationship between prop-control position, and blade pitch… aside from feather/beta, on some models.
Example… Take off with props full forward (high-RPM) leave them there… climb… level… descent…
The blades will have likely gone through their entire range of motion (maintaining a constant RPM), without having moved the prop-controls, at all.
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Last time I tried to fly the 414 mine had some weird autopilot bug where it would not hold altitude. So I put it in the hanger. I got busy at work. A few updates happened and I flew it last night again for the first time. Wow I am impressed. This might be my new favorite model right next to my PMDG 737.
Version 3.4.4 now available.
V 3.4.4 Hotfix
NEW FEATURES:
- A few Working circuit breakers. More to come. We wanted to get this hotfix out.
UPDATES:
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Updated the electrical system as we had a circuit drawing 20 amps when the battery circuit was on. This prevented to see a visual windshield draw test during the pre flight check since the Voltammeter can only show a max draw of 25 amps.
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The new AE was causing alterations to some of the electrical system and so when shutting down the left engine both alternators failed. This is now fixed and was reported to Asobo.
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The freeware Heavy-Division/B78XH never fixed their bug but we fixed it from our end. So the tablet and other touchscreens will now work with this addon.
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What does heavy division mod has to do with the C414 ?
They don‘t go well with each other installed and the 787 modder (who apparently caused the bug) has never fixed it.
This kind of thing is why I use MSFS Addon Linker. I only load what I need for the planned flight.
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I don’t have the Heavy Division aircraft, but my bet is they copied code related to the tablet subsystem from default code and changed it, but never made unique names for one or more of the functions they changed, so it interferes with other planes that attempt to reference the default code. Since the Heavy Division aircraft is loaded after the default code, its code takes precedence and breaks that code for everyone else trying to use it as it was designed.
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