fixing oil temp and pressure gauges when complex procedures is false

[gilbertohasnofb]

Closes #916

Now starting the sim with complex engine procedures set to false will not break the oil temp and pressure gauges. For testing purposes: if complex engine procedures is set to true, then toggle it to false and restart the sim to confirm everything works as fine, as the bug was present only when starting the sim with this property set to false)

[geoffmcl]

Applied the patch, and can confirm the temp and press needles now move ;=))

Even an excessive run-up, with full power and breaks, will quite quickly drive the temp off scale. But drops back into the green in normal flight.

Don't know how long they have been dead, and always meant to file an issue, but thanks for catching it.

[gilbertohasnofb]

@geoffmcl thanks for testing it.

Even an excessive run-up, with full power and breaks, will quite quickly drive the temp off scale... but drops back into the green in normal flight...

Yes, the question is if that's the realistic behaviour or not. I suspect it is, but I am really not familiar with the expected behaviour of oil temp and pressure in relation to the engine RPM. Same thing for the other behaviour I described the issue #916 concerning the oil pressure which does not raise to the green arc region while on idle. Perhaps @dany93 would be the person to tell if these are bugs or not.

But anyway, this PR simply fix an oversight from my side which resulted in temp and pressure being set at 0.0, so any tweaks to be done in the engine would be another story.

[dany93]

concerning the oil pressure which does not raise to the green arc region while on idle.

A bug ? Probably not.
But this oil pressure vs RPM is probably the standard behaviour in FG (unless it would have been changed by some nasal for the C172).
I don't know if the FG default behaviour has to be tweaked for the C172 at idle, I even don't know what the real behavior at idle is.

[gilbertohasnofb]

I even don't know what the real behavior at idle is.

Me neither, and this is what I meant by bug (sorry, bad terminology). I just wonder if the oil pressure does indeed stay at around 30 PSI at idle after startup even though the green arc in the gauge starts at around 50 PSI

[dany93]

Difficult to get reliable information on this, but I think that you might be right. I'd rather think that the oil pressure should rise to about 50 PSI (start of the green arc) at idle (about 600 - 630 RPM, throttle at 0%). Same or a bit higher at start of the engine (825 RPM, with throttle at 20%).

Real C172 pilots can easily confirm or deny.

In any case, that's not a big issue.

[gilbertohasnofb]

I'd rather think that the oil pressure should rise to about 50 PSI (start of the green arc) at idle (about 600 - 630 RPM, throttle at 0%).

That would be my guess as well. In the checklist I have, it says that the oil pressure should be in the green arc within 30 seconds of the engine startup (or 60 seconds in cold weather).

Real C172 pilots can easily confirm or deny.

@tigert @Juanvvc @stuartbuchanan would you know this?

In any case, that's not a big issue.

I think it might be an issue, since reaching the green arc is part of the checklist.

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@dany93 @wlbragg @onox By the way, this PR is ready to be merged

[onox]

Let's wait to see what they have to say about the idle oil pressure and open another issue if it needs to be changed.

[gilbertohasnofb]

👍

[gilbertohasnofb]

@tigert @algefaen @stuartbuchanan @Juanvvc Does any of you know something about what has been discussed concerning the initial oil pressure after startup?

[stuartbuchanan]

Hi Gilberto, I don't know enough about the Cessna, but certainly on my aircraft the oil pressure comes up within a couple of seconds when the engine starts, and stays in the green arc irrespective of the throttle position. On the ground, the oil pressure falling below the green arc would be a reason to immediately stop the engine to avoid engine damage.

…

-Stuart

On Thu, Apr 20, 2017 at 9:09 PM, Gilberto Agostinho < ***@***.***> wrote: @tigert <https://github.com/tigert> @algefaen <https://github.com/algefaen> @stuartbuchanan <https://github.com/stuartbuchanan> @Juanvvc <https://github.com/Juanvvc> Does any of you know something about what has been discussed concerning the initial oil pressure after startup? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#917 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AL4umHG4CwPNX8WsIL03EH6d6G0mpymtks5rx7tpgaJpZM4M4Csj> .

[gilbertohasnofb]

@stuartbuchanan thanks for the input, Stuart. I am 99.9% sure this should be the case in the 172 as well. I will open an issue for this and if any of the 172 RL pilots has anything to add, we would be happy to hear it.

[wlbragg]

Has anyone checked to make sure the number on the gauge match the actual property, may be a case of bad interpolation?