A32NX FBW Custom Autopilot

No, it’s just that people talk about all the funny stuff going on with the ATC in the base simulator that I was trying to avoid it until I get more serious and look into other options such as Pilot2ATC.

I guess it makes sense to rely ofnATC for ToD since in real life they are the ones that are going provide instructions regarding the STAR and approach.

Personally, I also don’t use ATC. I know it’s not realistic at all, but I don’t fly with live traffic enabled or anything so it’s not really an issue. I always use the NAV LOG on the world map/flight plan menu. Sometimes, the altitudes are a bit wonky and it gives you very precise, uneven altitudes, but I’ve pretty much gotten familiar with how far out I need to begin my descent (TOD). I’ve never run into any issues doing it this way.

And I know it goes by waypoints and NAVAID’s, but if there’s a large gap between any, like I said, I’ve gotten familiar with how far out I need to start my descent or to descend to a certain altitude.

I use the built in ATC. Coming from an X-plane POV, it’s light years better so I see the glass as 3/4 full. The few weird behaviors I have learned to ignore. Study the approach and related altitude requirements and when the ATC instructs you too differently, just ignore them. By the time you are on final approach it will catch up and if not, you can land anyway.

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You’re right, that’s managed descend or often called VNAV. It’s not yet implemented but is on the list to be done.

It might sound easy to be done but it’s a very complex matter…

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So I just finished a short practice/test flight with the new custom mod. I set up the MCDU accordingly and engaged manage mode for both airspeed and HDG/NAV. I set the cruise altitude to FL340. My cost index was set to 100 and NAV mode engaged. I departed using FLX power and then reduced to CLB when I got the flashing LVR CLB indication. I then engaged AP and let the plan do the rest. I’m happy to say, it went flawlessly. It maintained 250 under 10,000 feet and then climbed up to FL340 and reached Mach 0.78.

Well, that wasn’t so bad after all and I’m happy to say I think I’m ready for my real (non-practice) flight now! Thanks for all the help and advice guys!

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Well this is why I tend not to listen to other people’s saying. The ATC isn’t perfect, I admit. But I think it’s “good enough” for me. But whether that’s good enough for you. You should try it and experience it yourself. Just because other people are saying it’s doing funny stuff, doesn’t mean you will experience the same thing. Same goes the other way too. I’ve been using the built-in ATC and I’m pretty happy with it. But that doesn’t mean you would be happy with it too.

My point is, you should try things out for yourself and make your own conclusions. Don’t let other people’s experience affect your judgement.

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Fair enough, thanks for your imput… Will check it out as re-set controls and their still showing same results. Cheers

That’s good to hear Fearless. Yes the ATC is far from perfect but I use it to be lazy. If you are fast enough to start your descent when ATC says, you should be ok with managed speed. However, one thing you can do when you get the instruction is to manually reduce your speed first via the speed knob. Then when you set a lower altitude the plane will have a steep rate of descent to ensure you achieve the desired altitude in time.

As an aside, here is what I do during start up. After I have the systems fire up I let the AI radio call ATC to give the me the departure runway and initial altitude to input then I turn off the AI radio and continue with my preparations then turn on radio AI to call for pushback. If you don’t turn it off inbetween it will call for pushback too early! Also for even more laziness once pushback is complete and I want to taxi to the runway I turn on the pilot AI which then does all the taxiing to the runway for me. Only then do I take over for the take off. Just my way of doing things to make life easier. :slight_smile:

The latest Experimental version has a better descent rate nowadays than using the default Asobo autopilot. So whenever the ATC tells me to descent, I just set the new altitude and press it again to engage the LVL/CH, and it’s always reaching the targeted altitude on time with some time to spare until the next assignment from the ATC.

That’s true though, I make sure that AI ATC handling is turned off before I even start the battery otherwise it’ll ask for clearance and pushback too early as you said. After pushing back using the EFB Flypad, once the pushback tug is disengaged, I turn on the AI ATC control and I let it go and handle it.

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Yes I agree it mainly works for me. Only yesterday I did have a flight where it didn’t make it and I had to go around. You have to be pretty smart off the mark with starting the descent.

What I tend to is just commence a decent down to 3000 feet anyway. As you approach the ATC target it will just chime in and tell you to a new lower altitude anyway so you may as well just go for the 3000 from the off.

I usually have my mouse cursor ready at the knob. As soon as the ATC says the first word, I’m already turning it down and press the knob to start the DES and focus on the subtitle for the actual assigned altitude. I’m already on my way down before the ATC even finishes the sentence and when my copilot acknowledge the instructions. Hahha.

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Okay, so I’ve been watching a lot of your videos lately. I have another question though hopefully you can help me with. I notice you descend on managed mode as well. You just change the altitude and it descends on it’s own with no V/S input. However, I always notice that your descent rate is pretty high, like around 4,000 FPM. That seems a bit extreme. Obviously I understand that if you want to descend faster, you just use a steeper rate of descent. I guess I’m just curious, is 4,000 FPM a normal descent rate?

Is there a way to make the descent rate not so high in managed mode?

  1. The “managed” descent in the current versions of the A32NX mod is not like IRL managed descent. It is more like Open descent. They are still in the process of updating the descent logic but it will take time.

  2. To change the rate of descent, start the descent and then use the V/S knob to put in the vs you want. Then pull the knob to execute.

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Referencing number “2,” that’s exactly how I descend. I like to descend around 1,500-2000 FPM since it’s not as steep and seems more gradual and smoother.

But I remember NEO saying at some point that he never touched the V/S knob during descent and just left it in managed mode the whole time.

Yeah, maybe it’s not that realistic to have a descent rate that much. But I like it since the ATC tends to be quite late on the descent, using the managed descent tends to get me to the targeted altitude on time.

But if it’s not that realistic, then yes the FBW team needs to address the managed descent rate. I’m not sure if it takes the altitude constraints into account. You know as if it detects that you’re changing your altitude too late, and it automatically calculates to “catch up” so that it can reach the waypoint altitude on time within safety limits. But I don’t know, this is just my uneducated guess.

I suppose if you don’t want to descent too fast, and use a 3 degree descent angle like on normal situations. You can use the TOD calculator from the EFB FlyPad, enter your target altitude and calculate how far you need to start your descent.

Once you know when, you can switch to FPA/TRK mode instead of HDG/VS mode using the mode switch on the FCU. This will change the FD from a cross into a Bird icon. Then when you use the altitude knob to set the target alttude, pull the knob to engage an Open Descent mode, then use the FPA knob to target a -3.0º angle. And the sim will automatically set the best V/S rate to descent at a -3º angle. Which is generally about -1,500 fpm, give or take depending on the situation.

The risk here is that if you use the built in ATC, you would get multiple warnings that you’re not at the assigned altitude and please expedite to climb back. And so on, until it actually gives up and gives you the proper altitude assignment anyway as you get really close to the runway. But if you’re on IVAO or VATSIM online ATC network, you should be fine to use this method.

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Neo, you can just tell ATC to assign you a different altitude. Its not that big of a deal. And you dont need FPA/TRK mode when the TOD calculator gives you the correct vertical speed. You’re making things more complicated for him.

Also, as I said, FBW is already addressing the managed descent. You just have to be patient.

I’m happy with where it is right now. I’m not really bothered by the rate of descent. When they addressed it and it changes again, I’ll just adapt and adjust my flying style according. It’s not that big of a deal for me.

Yeah, normally I like to descend with a 1,500 FPM descent rate. I usually always start my descent around 150 nm or so from the airport, of course depending on my altitude. I’ve gotten really good at estimating when to start my descent and around how many miles until I need to reach my next desired altitude. Like I’ve said before, I just use the NAV LOG altitudes and usually they’re pretty accurate, but not always, so I just have to be careful sometimes.

Only one time using this method was I too high on approach. I just did a go-around, re-entered the pattern and approach at a lower altitude and landed successfully the second time. This wasn’t a case of the NAV LOG giving me the wrong altitude, but I just didn’t descend quick enough to reach that altitude in time. Basically It had me descend too much in a very short distance which placed me too high.

Anyways, I feel like only having one incident like this is pretty good for my method. And basically, all I’ve been doing is just switching the altitude, V/S, and speed out of managed mode. This way, I can also change my speed and reduce it as needed, or increase if it I want to fly a faster approach and make up some time.

Usually when I’m too high on approach, (usually because I was away during a cruise and got back to my PC too late to start my descent) I do what I call a corkscrew manoeuvre. I engage Selected heading mode, and turn the airplance 180 degrees away from the airport. Then when it’s close to 180, I turn another 180 degrees. Making it a 360 degree turn. All the while I’m turning I’m also descending. Kinda like doing a holding pattern.

So It’s practically keeping the descent without actually getting closer to the airport. If the glideslope is getting closer and crossing the centerline, I re-engage the NAV mode to get back to the flight path, and engage the APPR mode, then I’ll be at the right altitude for intercepting the glideslope. It avoids having to do a Go around enter the pattern again. But this is just me.