Reply To: Trim in the PMDG NGX

[webmaximus]

One more thing I would like to add while you’re looking into this issue is to also have a look at the stab trim. I think it was already mentioned but I still want to mention it again since it would be really great if this could also be fixed somehow in an upcoming update.

With HW trim disabled, the ELEC HYD pumps ON and a “neutral” stab trim value of 5 units set in the NGX both the physical as well as the yoke in the virtual cockpit will move back/pitch up to a large extent. This is also reflected if you look at the flight controls on the SYS page on the lower CDU in the NGX.

In the same situation but with HW trim enabled this doesn’t happen which is the correct behavior since the stab trim value should only affect the stabilizer and not the elevator in a 737. This since the elevator and stabilizer are two separated parts independent of each other. With HW enabled the yoke stays in a perfectly centered position along the pitch axis again reflected both looking at the physical yoke, the yoke in the virtual cockpit as well as looking at the flight controls on the SYS page on the lower CDU.

A bit hard to describe but please ask if I need to clarify the issue or if you need any additional details.

If you’re able to address the first issue allowing us to use HW trim that will also sort this issue since it’s only seen with HW trim disabled. However the downside using HW trim in its current form and how it’s implemented is you’ll not be able to affect the stab trim value in the NGX which again isn’t realistic. When you use the trim buttons you should of course also see how the stab trim value and the stab trim wheel in the NGX is affected.

I think I heard/read somewhere though this is not possible and if that’s the case there’s not much to do. Then we just need to figure out what would be the best and most realistic way in the NGX…to have HW trim enabled or disabled.

Another “solution” of course would be if you were able to sort the issue described above so we could keep HW trim disabled but still have the yoke correctly centered and not affected by changing the stab trim value.

I’m not sure if we have any real world 737 NG drivers in here but would be really awesome to have that kind of input to help finding the most realistic compromise when using the CLS-E yoke with the PMDG NGX.