MSFS24 SU4 – Seated Passengers external FPS severe drop + baggage trucks problem

[tonychenmusic]

Hello GSX Team,

I’d like to report a couple of issues observed in MSFS 2024 SU4 with GSX.

1. Seated Passengers (SP) cause severe external FPS drop
When Seated Passengers are enabled and properly initialized, external FPS drops gradually during boarding (for example, from ~40–50 down to low 20s) and does not recover for the rest of the session.
Closing doors, pushback, or restarting GSX does not restore FPS — only restarting the simulator does.

This has been confirmed on multiple aircraft (PMDG 737, FSLabs, Fenix).
Aircraft without SP support (e.g. Bravo 787) are not affected.
Internal/cockpit FPS remains normal.

Workaround: Disabling Seated Passengers immediately restores normal external FPS.

2. Baggage trucks remaining after loading / unloading
It also feels unusual that baggage trucks are intentionally kept next to the aircraft after loading or unloading is completed, rather than leaving once their task is finished.
This is especially noticeable after deboarding is fully completed, where trucks remain parked indefinitely.

Both issues are reproducible in SU4.

Thank you for your continued work on GSX. I hope this information is helpful and can be fixed too.

[virtuali]

1. Seated Passengers (SP) cause severe external FPS drop
When Seated Passengers are enabled and properly initialized, external FPS drops gradually during boarding (for example, from ~40–50 down to low 20s) and does not recover for the rest of the session.

That's normal: seated passengers ARE visible in External view, so they WILL cause an fps drop, nothing you add in graphic is free... during boarding, it's normal the fps would constantly drop, because we are displaying BOTH a progressively increased number of seated passengers AND the ones walking on top of that (which are even heavier on fps).

After boarding, the fps impact should be lower, because there's nobody walking anymore, but if the airplane is full of passengers and they are visible, you can't expect them to have zero cost on performance AS IF the airplane was empty.

Closing doors, pushback, or restarting GSX does not restore FPS — only restarting the simulator does.

That's normal as well,  GSX won't "empty" the airplane if you restart it.

Internal/cockpit FPS remains normal.

That's normal either: if you close the cockpit door, Seated Passengers are not displayed, that's how's supposed to be.

2. Baggage trucks remaining after loading / unloading

If you read the release notes, you would have known this is not an "issue", it's a change that has been requested by many users for a long time, they will be removed automatically upon Departure.

[tonychenmusic]

Hi, thanks for reply.

The thing is, in SU3, the seated passengers didn't cost this big fps amount. It's like over 20 fps after SU4, so it would be great if you look into it.

And for the baggage truck - it's reasonable to wait until pushback during departure, but it would be strange to leave baggage truck there after deboarding.

Now, the baggage truck remains there after deboarding, this would be a strange view. Hope this part can be fixed if the departure phase is normal.

Thank you!

[virtuali]

The thing is, in SU3, the seated passengers didn't cost this big fps amount. It's like over 20 fps after SU4, so it would be great if you look into it.

That's not what we observed:

- in SU2, invisible seated passengers had a basically zero effect
- in SU3, invisible seated passengers had a BIG fps impact
- in SU4, invisible seated passengers have some fps impact, much lower than SU3, but not as close to zero as SU2 was.

And for the baggage truck - it's reasonable to wait until pushback during departure, but it would be strange to leave baggage truck there after deboarding

The way it's supposed to work, is they remain only after Boarding is completed, they should work like before after Deboarding, but of course I'll check this is the case.

[tonychenmusic]

Hi, for seated passengers, I never had any FPS issues before SU4. Their impacts were small or negligible enough to be ignored.

But the last 2 days, I noticed it cost about 20 fps after the boarding is complete. And we have internal cockpit fps 40 - 50, while the external become 18 - 22ish, that's a disaster session. And after I turned the seated passenger off through the installer, now the external go back to normal.

So I guess there may be something in conflict with the SU4 update. I've tried it with different aircraft, including the newly released pmdg 737-800, so that's why I am reporting this to you.

Thank you~~

[tonychenmusic]

Hi,

Just to clarify, my concern is not that seated passengers have a performance cost — that is expected.

What seems different in SU4 is the magnitude and behavior of the cost in external view:

After boarding completes, external FPS can drop by ~20+ FPS

Internal/cockpit FPS remains high (40–50)

The session does not recover unless the sim is restarted

Disabling Seated Passengers completely restores normal external FPS immediately

This behavior was not observed for me prior to SU4, and it is reproducible across multiple aircraft.

So it feels less like a linear performance cost, and more like a change in how external objects are handled after SU4.

Just wanted to share this in case it helps identify any SU4-related interaction.

Thanks again for taking a look.

[virtuali]

After boarding completes, external FPS can drop by ~20+ FPS

What you should see, is some slight fps increase "after boarding completes", because at that time, we no longer have walking passengers, which are handled by GSX code: the only thing that remained are Seated Passengers, which are instead part of the airplane.

Internal/cockpit FPS remains high (40–50)

Assuming you had the cockpit door closed, that's how is supposed to be. If you open the cockpit door, do you see the same decrease as in the External view ? The passengers are the same and, except two very notable exceptions (iFly 737 and Fslabs A321), they are ONLY attached to exterior, they are visible in the interior because most of the airplanes are made in a way the exterior is visible from the exterior.

The session does not recover unless the sim is restarted

As I've said, GSX won't reset the seats when restarting, which is the only control it has over Seated Passengers. Other than that, they are part of the airplane (that's why they require the installer to enable them) so yes, it's normal it won't change anything if you restart GSX.

So it feels less like a linear performance cost, and more like a change in how external objects are handled after SU4.

There surely has been changes, but they started in SU3, but it's not as we can do much about it: other than making them invisible by setting a variable based on the camera and the cockpit view, they are in the hands of the sim optimization. Walking passengers are controlled by GSX, Seated passengers aren't.

[tonychenmusic]

Hi, thanks for the clarification.

Based on your reply, here’s a short summary of what I observed in SU4:

* Internal/cockpit FPS remains stable (40–50), even with walking passengers visible when the cockpit door is open.
* External FPS drops during boarding and does not recover after boarding completes. Once degraded, it stays low for the entire flight and only recovers after restarting the simulator (GSX restart has no effect).
* iFly 737: Seated Passengers cannot be fully disabled; external FPS remains permanently reduced once initialized.
* FSLabs A321: When Seated Passengers are disabled, external FPS immediately returns to normal and stays stable.

So in SU4, external FPS degradation caused by Seated Passengers appears non-recoverable within the same session, and aircraft-specific integration (e.g. iFly vs FSLabs) makes a significant difference.

Just sharing these observations for reference.

Thank you very much

[virtuali]

Internal/cockpit FPS remains stable (40–50), even with walking passengers visible when the cockpit door is open.

Assuming this means, it stays like that even if the airplane is almost full, so we have few walking passengers and a lot of Seated passengers ?

External FPS drops during boarding and does not recover after boarding completes. Once degraded, it stays low for the entire flight and only recovers after restarting the simulator (GSX restart has no effect).

Is this happening ONLY with the iFly 737 and FsLabs ?

That would be the one specific case where seated passengers are attached twice: both on the exterior and the interior model. So I would guess they would cause a bigger impact, if not properly optimized by the sim (because they are no longer under our control).

For ALL the other airplanes, the ONLY seated passengers attached are on the exterior model, so it's not clear if you fps stays up even when you have the airplane full of Seated Passengers and if there's a difference between iFly+FsLabs and other airplanes or not.

Initially, I didn't like the approach of attaching passengers on both exterior and interior, but this caused problems with the iFly 737, so we didn't activate them until those issue would be eventually fixed, they would likely be if iFly would eventually release a native model for MSFS 2024.

But before the FsLabs came out, since they also need that kind of attachment, we made a careful test with them, and noticed the fps impact was exactly ZERO, so we assumed the sim was very smart in optimizing them, so we agreed to keep the double attachment because we couldn't noticed any bad fps effect and surely passengers weren't drawn twice. But this was BEFORE SU3, so clearly something changed and, even if SU4 is better than SU3, it still not ideal as it was SU2 (and still is MSFS 2020).

That is, assuming you only see a big fps drop on these two airplanes in External views. If you see it with all airplanes in the same way, but not in internal view, I'm afraid they are just too much *combined* with the external view, that is looking at the airport. Do you see any improvement in flight ?

[tonychenmusic]

Hi, yes, internal/cockpit fps stays high even when the passengers are sitting there full. But the external drops.

And no, it's not just ifly and fslabs, I used them 2 just because you mentioned them in your previous message. No,  as far as I see it, it applies to all seated passenger aircrafts including fenix, pmdg.

So it looks like a problem in the external view as long as I turn seated passengers on.

Hope this clarifies it.

Tony