Pitch up on glideslope capture

[Wink207 78]

Hi all:

Has anyone else noticed a slight pitch up when capturing the glide slope from below? It is not a large pitch up but definitely noticeable. Also seems to happen on RNAV approaches. It results in an overshoot on the capture as the following pitch down is more than really required. Just me?

Thanks

Rick

Edited December 15, 2018 by Wink207

[Flysimware 647]

7 hours ago, Wink207 said:

Hi all:

Has anyone else noticed a slight pitch up when capturing the glide slope from below? It is not a large pitch up but definitely noticeable. Also seems to happen on RNAV approaches. It results in an overshoot on the capture as the following pitch down is more than really required. Just me?

Thanks

Rick

Try this with the default Cessna 172. It has a slight up pitch as well but when the nose drops its way late. The F50 is not late. Also we had to find a happy medium for the the RXP GTN because the RNAV approach has an issue and will cause a poor gs capture. We reported this to RXP and they are working on it. Once fixed we plan to adjust the settings to work better for the standard gs capture. But we are still happy with how it captures now.

Edited December 15, 2018 by Flysimware

[Wink207 78]

Me too 🙂

[RXP 2,336]

Hi, I confirm we are working to better our products in this department indeed. We are still a few days prior an update release.

NB: the pitch up command at GS capture is rooted in the FltSim autopilot code since FS9 up to P4D4.4. This is just the way they have coded the GS capture logic for the last 16 years at least and is therefore occurring with any aircraft using the simulator autopilot system.

[FDEdev 955]

40 minutes ago, RXP said:

NB: the pitch up command at GS capture is rooted in the FltSim autopilot code since FS9 up to P4D4.4. This is just the way they have coded the GS capture logic for the last 16 years at least and is therefore occurring with any aircraft using the simulator autopilot system.

That's incorrect. Just tried a few Carenado turboprops and jets. They are definitely using the standard FSX/P3D AP system and there's no pitch up on GS intercept. 

Edited December 15, 2018 by FDEdev

[RXP 2,336]

I won't argue but when you reverse engineer the FltSim internals it is clear the autopilot system is doing a small pitch up command.

Now, should an aircraft gauge/module or FSUIPC configuration 'compensate' for this is another story. Should the aircraft.cfg autopilot PID parameters or the aircraft flight model file also compensate for this is also another story.

But from a code logic, there is a pitch up command: this is just the way they have coded the GS capture logic for the last 16 years at least and makes me wonder if they haven't reversed the command value sign (they wanted a pitch down but it ends up in a pitch up) and forget about it in their source code all this time.

As a matter of fact while typing this, you make me wonder whether experimenting patching their code and see how it goes. I'll try this!

Edited December 15, 2018 by RXP

[FDEdev 955]

No FSUIPC, no special gauge etc... simply optimized basic SDK FDE design.

[ark 1,288]

Just had a friend over the house and he spent a couple of hours shooting ILS approaches into KBUR 08 with the Falcon 50. He remarked that the AP seemed to be doing a pretty good job. That was nice to hear because he is a retired B727 Capt (he likes planes with 3 engines!  😉).

Al 

Edited December 15, 2018 by ark

[scottb613 1,186]

Hi Al,

Now that's cool...

Regards,

Scott