A320 selected VOR approach 

Thanks, glad you like it. I will make more videos for sure.

I have not made a video about DME arcs but will add it to the TODO list. Climb gradients are not linear and are tricky to calculate properly over a certain distance. For the current climb gradient you can use the vertical speed and Ground Speed, then convert that to a percentage: % = (fpm / GS) * 100

On a VOR approach you can't land with the flight directors because there is no suitable lateral and vertical mode available after passing the minima. The AP is usually disconnected at about 1500 ft or 1000 ft, provided you are visual. This gives you some time to align with the runway in case of an offset approach. The AT is never disconnected with an Airbus unless you do a raw data ILS approach. The methods I describe are more safe and provide less workload (a fully managed approach is better but that is not always legal). It might be hard to understand why that is the case. It takes a lot of experience to understand the reasons behind it.

That is a good question. There are a few different reasons why the VDEV can be wrong. One reason is that the VDEV path is calculated for a certain descent speed. If you fly a different speed, then the VDEV path will be wrong. The other reason is due to the IDLE PERF factor which is coded in the FMS. This factor can be modified (usually only allowed by engineering) to be overly conservative or the other way around, leading to the VDEV being off for normal operations. Another reason why the VDEV can be wrong is when there is a big descent head or tailwind which was not programmed in the FMS. Yet another reason (and the most common reason) why the VDEV can be wrong is when you expect a shortcut. The aircraft does not know about any impending shortcut and will happily show that you are on profile, until you get a shortcut when suddenly it shows that you are above profile. You can see that coming but the aircraft can't, which is why the VDEV can be wrong. Another reason when the VDEV appears to be wrong is when the aircraft is on the light or heavy side. Using my method, I do not calculate for the weight in order to reduce workload. However, that does not mean that the weight does not have any effect. Obviously, it does. But instead of calculating for it, I "take it into account", using some common sense. This is why the VDEV in this particular video appears to be wrong (actually it isn't because the aircraft calculates for the weight while I don't) But as you can see in the video, I state something like "we are 1000 ft low on profile, but we are also heavy, so we leave it for now", You can see later that we are slowly getting back on profile all by itself (a heavy aircraft has a shallower descent angle). This is the effect of the weight. So basically we reduced the workload by not calculating for the weight, but still taking it into account leading to the energy management still being correct. I know it might be a bit hard to get, but I hope it helps.

@@a320descentenergymanagemen3 Ahh yes, makes sense. Absolutely satisfactory anwer, thank you for your time.