Engine failure feature not consistent.
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Hello fellow sim aviator. I’m just wondering if you tested the engine failure. I have done some test and according to the condition that should trigger that to happen, it only happened to me once.
If I remember correctly the manual explain that if we let the engine above recommended setting damage should start after 10 sec or so.
In my test, I had let the engine run in different scenarios for minutes (5-20) without any damage done, still showing 0%.
BTW, this is my favorite airplane.Thank you.
Fly Safe
o7
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@sadsky there's actually a valve that should release the pressure if you overboost in real life, so the failure mode is more the failure of that which then leads to the failure of the engine. As such, an element of random behaviour has been built in to the code so that you will not instantly blow the engine each time.
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@delta558 said in Engine failure feature not consistent.:
@sadsky there's actually a valve that should release the pressure if you overboost in real life, so the failure mode is more the failure of that which then leads to the failure of the engine. As such, an element of random behaviour has been built in to the code so that you will not instantly blow the engine each time.
Are you sure that's correct, because it doesn't seem to be consistent with what I've read online by real world Turbo Arrow pilots?
From what I've read (here for example: https://forums.flyer.co.uk/viewtopic.php?t=63214) it's not failure of the "valve" (wastegate to use the correct name) that causes the problem. According to this, because it's a fixed wastegate (unless it's been modified), the engine must be controlled by the pilot to prevent overboosting, with failure of the pilot to do that being what causes engine failure (not failure of the "valve"). If the pilot doesn't control it the engine can be overboosted even if the wastegate ("valve") has not failed.
That actually makes more sense to me but maybe I've misunderstood the real world Turbo Arrow pilots???
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@sender46 from a couple of the beta testers who either own or fly Turbo Arrows, there was surprise at the instant onset of failure created in the early betas from over boosting. We asked, they explained!
You appear to presume that my use of the word 'valve' was in place of the word 'wastegate' - not the case. The Turbo Arrows (unmodified) have a fixed wastegate and this is what causes the requirement to manage the throttle to prevent overboosting and damaging the engine. However, there is also a separate overboost valve which apparently will open at 42in mp (1in above the 'max'). Note, this does not make it a variable wastegate which adjusts according to pressure and throttle, it's effectively just an 'escape valve' for careless handling which you should not be doing!
Hope that makes sense, we set up the P3D version as you expect, but gained more information during beta testing for the MSFS version.
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I agree with @sender46 on this one.
I have always flown the turbo arrows in the sim (as I would in real life) limiting the MP to below the maximum so I wasn't aware of this. The fixed waste gate that comes stock on the turbo arrow means you can't use full throttle or the engine will be damaged.
Many owners modify their turbo arrows with an automatic waste gate so they don't have to worry so much about damaging their engine and reducing workload on the takeoff roll. It is entirely possible that the turbo arrow Just Flight used to create this add-on had an automatic waste gate but that would have been an after-market modification.
I think if that is the case the add-on should be marketed as such (make it clear in the product description that this is a Turbo Arrow with aftermarket automatic waste gate modification) or allow us to switch out some files to set it back to stock (fixed waste gate).
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Sorry @Delta558 I didn't see your reply before I posted my own.
That is very interesting and I've just had to have a search around to find more info on this overboost valve.
Thanks for the further info, always glad to be able to learn new things about these systems!
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@delta558 I stand corrected. Thank you for the clarification. That explains it nicely.
I've since found the Piper Turbo Arrow IV Information Manual, which explains this further:
https://static1.squarespace.com/static/58fe2dcfff7c500a04eda841/t/5c330a8b032be4fbaf385d84/1546848957043/AFM_HBPPB-compressed.pdfFor information, section 7.5 in the above manual provides the following details:
The turbocharger control system is a fixed, ground adjustable orifice ("fixed wastegate"), and is adjusted to provide 41 inches MAP at full throttle at 12,000 feet density altitude. Throttle position controls engine power and no separate turbocharger control system is utilized. An overboost valve prevents manifold pressure from exceeding 42 inches Hg. should the throttle inadvertently be opened too far below 12,000 feet density altitude. Should this occur, the amber "overboost" warning light in the annunciator panel will illuminate.