Yeah I always end up over speeding. Strange thing is one time I was able to keep the speed in the white arc with over 2000 fpm steep descent (Beta mode) but I did that pulling back on power and using the AP VS mode. I don’t think you are suppose to use Beta mode with AP?
Is it possible to verify if beta mode is engaged or not? I am never really sure weather it works or not. I noticed you get a low pitch warning as soon as you go into reverse but for the beta I did not notice anything.
For beta you need to fly level and reduce the throttle to idle. Let the airspeed drop below a 100 knots (or was it 90?). Once the RPM drops below 2,000 that should be your indication that the prop is now ungoverned and in beta mode. Now you can initiate your descent with with or without flaps.
Somebody please correct me if I’m wrong.
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That’s basically it. Then keep your descent rate constant without overspeeding or stalling…
whats the difference between the working title g1000 on github and the g1000 nxi and will the former work with porter?
Is there somewhere a list of the variables (Lvars) available that we can use to map all the switches to home cockpit equipment?
The one on github, or on the working title websiteis the old legacy version. The NXi is the new one, exclusively available on the marketplace. AFAIK, none of both work correctly (yet) with the pc6 as they are not customizable for devs. You can use them, but there will be wrong engine indications and autopilot issues.
I usually use flaps when descending in beta mode. What works for me is to fly level and throttle back(not all the way) until I reach a speed slow enough to extend flaps. I then pull throttle all the way back(you’ll hear it hit). I then continue to fly level or even try to gain some altitude. They speed should drop rapidly and you can almost feel the plane decelerate. Before it stalls, nose down and begin beta. You should be able to descend at 30 degrees or more and stay under 80 knots, flaps fully extended.
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If you turn on devmode you can see the active lvars. There aren’t many custom lvars though, it’s mostly default MSFS/simconnect.
Background on beta mode…
For this you have to understand how a constant speed prop works.
The beta mode only becomes available if the blades are at their full fine pitch stops.
Let’s say you are flying in cruise, power is applied, you’re doing 120kt. The prop blades are somewhere between fine and coarse, so that 2000RPM are maintained.
Then you decrease the power to idle. What happens? The commanded RPM is still 2000,but your airspeed is dropping. In order to keep 2000rpm, the blades have to go towards fine.
The airspeed drops further, the blade angle is further driven to fine, but at some point there is a stop-the full fine pitch stops (or alpha stops).
The prop is now in its fullest fine position of the governing range. This happens around 100kt, depending on how the prop was rigged at the workshop it can be a bit more or less.
However, only at this point the beta mode becomes available-the prop blades are at the full fine pitch stop. If you now reduce to idle (or are already in idle) the beta valve opens and the blades are driven to a much finer angle, creating maximum drag. It’s only drag, not reverse. Think of it like it’s creating a solid disc standing in the wind, a huge speed brake.
Now with 1900RPM set, what happens?
You dial back the power, airspeed drops, but the wind force is able to drive the blades at 1900RPM much longer before they hit the fine stops… around 90kt. As beta only depends on the fact that the blades are at these stops, beta will only become available then, at around 90kt with 1900rpm set.
For the rate of descend, the faster you go while in beta, the quicker the descend, because the resistance rises squared to the airspeed. Typically you will descend at 100kt, but you can also try 110 or 120kt. The 100kt only need to be matched to get INTO beta, but not to keep it there.
Once you apply power again however, and the RPM rises above the set speed, you’re out of beta and in governing range again.
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It’s a really cool feature but I’m wondering how the pilots deal with the pressure change that occurs when descending that quickly? I know a common rule of thumb is to descend at about maximum 500 ft/min for passenger comfort.
They don’t have passengers because those already jumped out. 
The pilots wants to descent quickly to be able to pick up the next group of skydivers. So the pilot certainly has to be able to deal with it but he does not have to worry about passengers usually.
With “all the way”, I hope you mean to idle. Because you must not enter reverse in flight!
Yes is quite good. On the real one when you engage beta range first of all you notice a change of sound ( very charatteristcs sound and different to a beta range on the ground) ,than the prop RPM decrease a lot: On my porter for example if i leave the power lever on idle position the rpm decrease at 1300RPM at 110kts and 25 degress nose down. But every porter is different and also his beta range setting is different and depends of how the prop is regulated.
if you move foward the power lever on beta range you can increase the prop RPM and try to select your best prop setting between 1300 and 1900( usually the range between 1500 and 1700 RPM produces a lot of vibration). If you overcome 1900 RPM you can disengage beta range.
Also beta range is affected by altitude, more altitude = lower speed to engage: at 2000FT i can engage beta at 100KTS, at 14000 i have to be below 75 KTS!
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That is an exceptional explanation of how beta works. Thank you for that.
Yes…just to idle.
Ladies, gents… I have a question that someone MAY be able to assist with as the documentation doesn’t seem to touch upon this. I am currently doing some rather long legs ferrying the aircraft from Canada to Antarctica. This requires me to have 100% fuel, so I have the external tanks full as well. From what I understand, the way to use fuel in external tanks is to enable the pump for both of them and it will then transfer the fuel from external to main… or perhaps not transfer but use in supplement to main - I haven’t measured whether the rate of consumption from the main tanks decreases with those pumps on. So that’s the first part of the question…
The second part deals with the fact that initially when I select external tank pumps to be on, I get a FUEL FLOW warning in yellow on the PFD for whichever side I have enabled the pumps for. Those warnings, as I have noticed, will eventually go away. But they come on, regardless. What can be done to make sure that doesn’t happen? Also - if those external tank pumps are on, do they require the main auxilliary pump on the left to be on? Or can that be left off? Because, realistically, during most of the cruise, those external pumps will be on.
Many thanks in advance! 
I also have a question: when I took the bird all the way up to 23,000 feet the oil temperature rose to max temperature and I got a warning. The temperature wouldn’t go back down even when I descended all the way to the ground. Is that a strange behavior that can be seen in real life, and if so, what did I do wrong, or is it a possible bug?
Hey @BostonJeremy77, the PC6 ‘fuel flow’ annunciations with come on if you turn ON the external-to-main transfer pumps when the mains are above 90% capacity as a caution against overfilling the mains.
There’s no requirement for the main auxiliary pump to be left on when the transfer pumps are active, not in the Milviz model at least.
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Thank you so much!!!
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