[RESOLVED] Problem with 3rd party aircraft solved in odd way

Any issues, problems or troubleshooting topics related to the Prepar3D client application.
Locked
Ray Proudfoot
Posts: 517
Joined: Thu May 18, 2017 8:19 am

[RESOLVED] Problem with 3rd party aircraft solved in odd way

Post by Ray Proudfoot »

I recently upgraded to v4.4 from 4.3. I loaded my favourite aircraft - the Xtreme Prototypes Learjet 25. But after starting both engines the left one kept spooling down during taxi and it made a take-off impossible. I wondered if it might be a problem with the Saitek Throttle Quadrant so I temporarily switched throttle 1 to a different axis.

The problem remained ruling out a hardware problem. But this aircraft had been fine with v4.3. I thought about what might be responsible. I had updated the client and content only.

I decided to delete the contents of the Shaders folder. This fixed the engine problem but I’m puzzled why it should. Can anyone shed any light on why this cured the problem?
Ray (Cheshire, England).

System: P3D v5.3HF2, Intel i9-13900K o/c to 5.8GHz, Nvidia RTX 4090 24Gb, 32Gb Corsair DDR5 RAM, Asus ROG STRIX HERO mobo, Crucial T700 4Tb SSD, Win 11 Pro, BenQ 32” UHD monitor, Fulcrum One Yoke
User avatar
Beau Hollis
Lockheed Martin
Posts: 2452
Joined: Wed Oct 06, 2010 3:25 pm

Re: Problem with 3rd party aircraft solved in odd way

Post by Beau Hollis »

We version the cached shaders, so you shouldn't get 4.3 shaders trying to load in 4.4. If you had any 3rd party add-ons that modified the sahder source, the compiled shaders might have been in a bad state. It's also possible the compiled shader file could have become corrupt if there is hard drive issue or the app was killed in the middle of writing out a file. Finally, we've seen some cases where GPU or driver changes have lead to difference in the compiled shader output. If have issues after swapping out GPUs or updated drivers, it can be good to clear them out.
Beau Hollis
Prepar3D Software Architect
Ray Proudfoot
Posts: 517
Joined: Thu May 18, 2017 8:19 am

Re: Problem with 3rd party aircraft solved in odd way

Post by Ray Proudfoot »

Thanks Beau. It does sound like it was a corrupted file given it was a 3rd party aircraft that may still have been using a file from 4.3.

The fact there is a link between 3rd party aircraft and the shaders folder suggests the problem lay in that folder.

Happy for you to close this as resolved.
Ray (Cheshire, England).

System: P3D v5.3HF2, Intel i9-13900K o/c to 5.8GHz, Nvidia RTX 4090 24Gb, 32Gb Corsair DDR5 RAM, Asus ROG STRIX HERO mobo, Crucial T700 4Tb SSD, Win 11 Pro, BenQ 32” UHD monitor, Fulcrum One Yoke
Locked