OnCourse Software

Hi, Since 3.21.9 I keep getting the above error message (which I've never encountered before) when changing the altitudes in the flightplan page.
It says I cannot descend before TOD at Leg 21, which is way past the correct for the flight. Same in 3.21.10, going back to 3.21.7 solves it.
Is there a setting I need to change?
Or is it a bug?

No it's not a bug and is intended to prevent you from making a bad flight profile... see below and I apologise for my poor skills at using MS Paint

-

Thanks Dave, but I'm not sure I understand- I haven't changed the way I plan flights but the error has only started in 3.21.9, and it did resolve when I reverted to 3.21.7.
I'll try to show some screenshots next time it happens to see if you can see if there's something I'm doing wrong?

Yes but prior to 3.21.9 you could create an incorrect profile which could then cause other issues... screen shots would be great

It gets very strange...
I put 3.21.10 back in and tried the same flightplan, and it didn't give the error.
I'm afraid I have no idea about programming/coding, but has something changed that makes the error happen only after 21.7 and then does using 21.7 change the fp so that solves the problem so that 21.10 then works?
Do 21.9 and 21.10 have the TOD hard wired in and therefore ignores any changes made in the adjustment page as I am 100% sure that all the altitudes were correct when I first tried them ie sequentially lower.

Did you try making the same changes or were you just confirming to use the existing adjustments file?

If you can recreate the problem and then send me a screen shot plus the relevant file from the Flight\FPP\Adj file I should be able to see what's happening. Basically, as you already know, PF3 will put your cruise altitude into waypoint 1 and subsequent waypoints and then create a descent profile... let's say starting at waypoint 20. So if you want to change the altitude in one or more waypoints you cannot enter a lower altitude than what's in waypoint 1 unless you also change waypoint 1, because you be created a descent before waypoint 20. Hope that's a little clearer

I think I understand a little more now.
Since 21.9 you have added a TOD waypoint before which you cannot descend from the cruise without triggering the error message?
I think the flightplan I was using had an early descent due to a STAR restriction.
I can think of a couple of ways of getting round the problem (using the H+ when still climbing to increase the cruise level or reducing the descent rate on the Load FP page)
I'll see how I get on in the next few flights and report back.
Thanks for your support.

Tigerhawk wrote: *

Mon Oct 23, 2023 5:01 pm

Since 21.9 you have added a TOD waypoint before which you cannot descend from the cruise without triggering the error message?

Not quite, perhaps I can explain the restriction differently; it has always been there, but wasn't working correctly:

There can only be only one Top of Climb (TOC) and one Top of Descent (TOD) position, both initially at the assigned cruise altitude.
On the way up to TOC there can be several steps; normally PF3 will set the first waypoint to the cruise altitude and assign appropriate steps.
Similarly, PF3 will assign a number of steps down from TOD, generally to the final approach altitude.
If you need to set specific waypoint altitudes then you need to ensure that they increase towards TOC, and decrease after TOD.
The updated version of PF3 simply enforces this restriction, and won't allow you to save a 'bad' profile.

Hope this helps,
Martin

Hi again,
This is an example of what the problem is - the STAR restriction into Gatwick is to be at FL140 at SIRIC, but PF3 is saying the TOD is WP18 which is only 7 nm from SIRIC.
To be at FL140 I need the TOD to be before WP16.
Any ideas on how to resolve this?

Thanks Dave... there was certainly a small logic problem there which I believe is now fixed. I will try and upload another beta this evening for you to try. Thanks for the feedback