Very low FPS with MH-60 after MSFS 2024 SU5 – MainThread bottleneck, only happens with this aircraft

Hello Miltech team and community,

I would like to ask for help regarding a serious performance issue I am experiencing with the Miltech MH-60 in MSFS 2024 after the SU5 update.

The problem is that the MH-60 is giving me extremely low FPS compared to every other aircraft I use in the simulator. This seems to happen only with the MH-60. Other complex aircraft, including the HPG H145, run normally on the same system, same simulator, and similar graphic settings.

My hardware is:

• **CPU: AMD Ryzen 7 9800X3D
• **Motherboard: MSI MPG X870E Carbon WiFi / MS-7E49
• **RAM: 64 GB DDR5-6000, EXPO enabled
• **GPU: NVIDIA GeForce RTX 4090, 24 GB VRAM
• **Main SSD: Samsung 990 PRO 2 TB NVMe PCIe 4.0
• **Resolution: 7680 × 1440
• **DLSS: Quality
• **Frame Generation: Off during testing
• **FPS limit: 60

The MH-60 is installed through Contrail as:

MH60 v1.1.0 – MSFS 2024 Native

I installed it into the MSFS 2024 native Community folder:

Community2024

I also uninstalled and reinstalled the aircraft to make sure the installation was clean.

The issue is shown clearly in the MSFS SDK FPS display. With the MH-60, I am getting results like:

• **FPS: around 14–22 FPS
• **Limited by: MainThread
• **MainThread: up to around 102 ms
• **Graphics Queue: around 14–16 ms
• **CoherentGTUIThread: around 8–10 ms

One of the worst readings I captured with the MH-60 was approximately:

• **FPS: 14.9
• **Frame time: 66.90 ms
• **Limited by: MainThread
• **MainThread: 102.9 ms
• **RdrThread: 10.2 ms
• **Manipulators: 8.9 ms
• **CoherentGTUIThread: 10.2 ms
• **Graphics Queue: 16.1 ms

This suggests that the problem is not GPU-related, because the RTX 4090 is not the bottleneck. The aircraft appears to be causing a very heavy MainThread load.

For comparison, with the HPG H145 in the same simulator, with high/ultra settings and very high LOD settings, I get around:

• **FPS: 60
• **Limited by: Graphics Queue
• **MainThread: around 13 ms
• **Graphics Queue: around 14 ms
• **CoherentGTUIThread: around 4–5 ms

So the simulator and my hardware seem to be performing normally with other aircraft.

I have already tried the following:

• Lowering Terrain LOD and Object LOD
• Lowering glass cockpit refresh rate
• Lowering traffic and airport services
• Testing with DLSS Quality
• Testing with Frame Generation disabled
• Reinstalling the MH-60 native version
• Making sure the aircraft is installed in the MSFS 2024 native Community2024 folder

Despite this, the MH-60 still produces a very high MainThread time and very low FPS.

Has anyone else experienced this issue after MSFS 2024 SU5?

Is this a known issue with the MH-60 native version, or could there be a specific setting, variant, livery, duplicated folder, or compatibility issue that could cause such a heavy MainThread bottleneck?

I would appreciate any advice or troubleshooting steps.

Thank you very much.