Despite the acrimony, I appreciate all the related posts. TIL, etc. 

14 hours ago, Murmur said:

I think the collective was not touched in flying_carpet video, N2/Nr rising is just the effect of runaway fuel flow.

If no one is moving the collective the behavior of the torque is not correct for that kind of failure, but like someone said in this post, this is only a default helicopter.

I would like to see a "complex" helicopter well simulated in any simulator but seems we will never have one.

49 minutes ago, Soul Rebel said:

If no one is moving the collective the behavior of the torque is not correct for that kind of failure, but like someone said in this post, this is only a default helicopter.

Why? A sudden and uncontrolled increase in fuel flow should produce a temporary torque spike (allowed by the fact that rotor RPM increase is not instantaneous, because of its inertia), then when the rotor RPM increases as well, torque should decrease somewhat again.

Not saying it's correct in terms of numbers, probably the real helicopter engine/rotor system would fail before it reaches those overspeed/overtorque values.

31 minutes ago, Murmur said:

Why? A sudden and uncontrolled increase in fuel flow should produce a temporary torque spike (allowed by the fact that rotor RPM increase is not instantaneous, because of its inertia), then when the rotor RPM increases as well, torque should decrease somewhat again.

Not saying it's correct in terms of numbers, probably the real helicopter engine/rotor system would fail before it reaches those overspeed/overtorque values.

All overspeeds based on governor failures that I have seen in several real helicopter simulators the torque will remain in the high position until you regulate the fuel flow manually. And that's logical because now your governor is leting pass the same amount of fuel all the time until you regulate it manually.

Sorry if I'm not explaining it well, english isn't my mother tongue.

2 hours ago, Soul Rebel said:

All overspeeds based on governor failures that I have seen in several real helicopter simulators the torque will remain in the high position until you regulate the fuel flow manually. And that's logical because now your governor is leting pass the same amount of fuel all the time until you regulate it manually.

I suspect that's a different failure mode. I understand you're referring to a failure in which the governor keeps a fixed fuel flow, so the torque is not immediately affected.

The failure in X-Plane should model a failure where the governor causes a runaway fuel flow to the max, and a subsequent spike in torque.

Anyway, it's probably not 100% accurate (just the fact it happens simultaneously for both FADECs is unrealistic). I'm curious to know if there are study level add-ons helicopters for X-Plane that accurately model those types of failure.

3 hours ago, Murmur said:

probably the real helicopter engine/rotor system would fail before it reaches those overspeed/overtorque values.

Even if it doesn't

e.g. in the AW109GN it's very easy to overspeed the rotors during approach.

Even if there is nothing visibly wrong, the maintenance bill for doing so is €350,000, and the computers won't let you fly until that maintenance is completed.

Know someone who learnt that expensive mistake the hard way.

My point here is, we are quite a way off any of the helicopters having the care and attention Totoro gave to simulating the RW behaviour of the CL650, they are at least if not more complicated, and up until recently the default S76 didn't even have absolute basics like autorotation passing an eyeball inspection.

We are only just reaching the point where these things are possible to even notice in the sim.

Edited August 13, 20232 yr by mSparks

X-Plane 12 (Z):

... the zenith of civil desktop flight simulation - zones where no man has gone before (some zealots will object ...). No video here, that's simply the summary of this video series (as I've reached the end of the alphabet). Is this the end of my video series? Let's wait and see ... 😁

Ok, did you think my little series has ended? No way! Although my strictly alphabetical list is finished, I will still post more videos. Let the games begin!

Almost an accident - due to failed actuator for ... see for yourself (default airplane).

 

Breathtaking Boeing 737 ...

... battling the wind. And not only the B737, but also the Beech Baron (and other X-Planes). A blo.dy brillant ground physics simulation. Better than anything I've seen before, anywhere.

 

This (and others) is the reason why I don't go ...

9 hours ago, turbomax said:

... back to the "glorified scenery simulator"

😂🤣

Edited August 30, 20232 yr by flying_carpet