OnCourse Software

Welcome to our Product Support Forums

Advanced search
Board index » PF3-ATC at its best

Constantly too late TOD !

PLEASE NOTE:

If you are reporting an issue with PF3 please remember to Zip and attach the Debug_Monitor.log file from your PF3\Logs folder. Thank you.

Post Reply   Page 4 of 7  [ 61 posts ]
Jump to page « 1 2 3 4 5 6 7 »
Author Message
RALF9636
Post subject: Re: Constantly too late TOD !
Posted: Fri Apr 01, 2016 10:12 pm
Offline
 
Posts: 368
Joined: Mon Feb 08, 2016 8:29 pm
 
Might the problem simply be the following:

We expect PF3 to make us descend in time to reach a certain waypoint at the altitude that is set in the Adjust ... flight plan page - and that is how it should work. But I have the impression that PF3 sometimes waits for us to reach that waypoint before it clears us to that altitude. So in Martins example he couldn't reach RESMA at 15000 ft. but was told to descent to 15000 ( with a step at 24000 because of the large interval) when reaching RESMA.
That would also match the experience I had in the flight I posted above.
And it would explain why some flights are going fine: if the waypoints are close to each other with only 2000 or 3000 ft between them, this problem would be barely noticeable whereas it is a severe problem with waypoints far away from each other.

If this is the case a workaround would be to shift all target altitudes one waypoint up.

Just a shot in the dark but maybe worth a try.

Ralf

_________________

[ img ]
Top
Profile Quote
martinlest
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 1:25 am
Offline
 
Posts: 1308
Joined: Sun Dec 26, 2010 3:33 pm
 
Quote:
It seems that you are expecting PF3 to somehow magic a perfect fpl
Quote:
Please get your facts right as PF3 asked you to reduce your speed to 200 not 180
Quote:
No wonder you had so much trouble you were not checking your speed
Quote:
there are just too many end user errors in the log
Quote:
Fly it at the correct speeds and pay attention to any ATC instructions.
Quote:
PF3 is not a flight planning programme it is an ATC programme
Enough! I am now totally pissed off with your patronising comments in this thread and others. Whatever you think you have found in the logs certainly does not represent what happens in the flights here and much of the above is just rubbish! And "pay attention to any ATC instructions" - damned nerve!! - as if that's not what I am doing - I have been flying FS since Fs98 (as well as flying small a/c real world) and I have a pretty good idea of what ATC should be doing. You talk to me like a school mistress to a schoolboy.

I am not wasting any more time posting about PF3 when you are clearly not going to take seriously the fact that there is a problem with it. It should not be telling me to descend from 34000' (at a waypoint which is marked to be passed over at 15000') to 2000' within the space of a few minutes, and so near the airport. SID/STARS have nothing to do with it, they don't come into operation at that distance.

I shall probably go back to PFE, which gave me no such problems - ever! Had I been as dumb as you paint me I might have expected some issues there too. It's really not good policy to annoy customers (who have bought everything Oncourse has ever issued!) like this!!
Top
Profile Quote
Dave March
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 7:33 am
Site Admin
Offline
 
Posts: 6124
Joined: Mon May 18, 2009 6:22 pm
Location: Sawtry, Cambridgeshire. UK
Contact: Website
 
May I suggest everyone just take a step back and a deep breath. Rest assured I am looking into this and will report back once I have something relevant to say.

Sent from my phone using Tapatalk

_________________

Cheers

Dave March

Email: dmarch@oncourse-software.co.uk

I don't know if my memory is getting worse as I get older...
...I just can't remember how it used to be!

[ img ]
Top
Profile Quote
awralls
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 7:40 am
Offline
 
Posts: 36
Joined: Wed Feb 24, 2016 9:14 am
 
Martin, you're not alone; I share your frustration. PF3 seems to be coded based on certain assumptions...

1) everyone using it is flying modern aircraft capable of high rates of descent.
2) everyone is flying current procedures (SIDS/STARS etc)
3) the user flight planning will provide a descent profile that saves PF3 from having to calculate one of its own based on aircraft performance and physical conditions IE speed, altitude and position.

I recognise that this probably describes the vast majority of users, so there will be few who would be unhappy.

However, if you deviate from those criteria, you'll experience frustration, sad to say. I'm not sure it is recoverable since only Dave will know to what extant it is still using legacy code from PFE which was itself dependant on very old code for a previous application. I hope it can be recovered but until it is, I have, with regret, gone back to RC4.

Andy
Top
Profile Quote
awralls
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 7:45 am
Offline
 
Posts: 36
Joined: Wed Feb 24, 2016 9:14 am
 
RALF9636 wrote:
Might the problem simply be the following:

We expect PF3 to make us descend in time to reach a certain waypoint at the altitude that is set in the Adjust ... flight plan page - and that is how it should work. But I have the impression that PF3 sometimes waits for us to reach that waypoint before it clears us to that altitude. So in Martins example he couldn't reach RESMA at 15000 ft. but was told to descent to 15000 ( with a step at 24000 because of the large interval) when reaching RESMA.
That would also match the experience I had in the flight I posted above.
And it would explain why some flights are going fine: if the waypoints are close to each other with only 2000 or 3000 ft between them, this problem would be barely noticeable whereas it is a severe problem with waypoints far away from each other.

If this is the case a workaround would be to shift all target altitudes one waypoint up.

Just a shot in the dark but maybe worth a try.

Ralf
I found I used to have to do that with PFE and the result was that I ended up being descend anything up 100 miles before my calculated TOD.

Andy
Top
Profile Quote
ThomasAH
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 9:09 am
Offline
 
Posts: 988
Joined: Tue Dec 24, 2013 12:27 pm
 
awralls wrote:
PF3 seems to be coded based on certain assumptions...

1) everyone using it is flying modern aircraft capable of high rates of descent.
2) everyone is flying current procedures (SIDS/STARS etc)
3) the user flight planning will provide a descent profile that saves PF3 from having to calculate one of its own based on aircraft performance and physical conditions IE speed, altitude and position.
As I wrote elsewhere: Absolutely not.

* If PF3 says otherwise, it is a bug. Report it (like you did) and Dave will look into it.
* If someone else says otherwise, just ignore that.
* If Dave says otherwise: Start complaining, I will join you :)

Regarding 3: Of course you may want to adjust the waypoint altitudes if you want to comply to real-world regulations or want to avoid terrain, but even without that PF3 should provide you step descents that work.

But as in real life: If you reach your TOD and ATC does not clear you to descend, just request a lower altitude.

_________________

[ img ]
Top
Profile Quote
ThomasAH
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 9:52 am
Offline
 
Posts: 988
Joined: Tue Dec 24, 2013 12:27 pm
 
dmarch wrote:
Rest assured I am looking into this and will report back once I have something relevant to say.
Something I found in the logs:
Code: Select all
TOD recalculated now distance is set to 236 NM
(and the other calculations are in a similar range)

The length of the flight plan is only 284 NM!

With a preset descent rate of 1000 feet per minute and a height differential from cruise alt to destination of about 27500 feet, the descent would need about 27.5 minutes.
With speeds between 180 and 280 knots this should only be between roughly 82 and 130 NM.

Note that I did not include FAF distance/alt or GS vs. IAS in these calculations, but something looks wrong here.

_________________

[ img ]
Top
Profile Quote
awralls
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 10:49 am
Offline
 
Posts: 36
Joined: Wed Feb 24, 2016 9:14 am
 
Thomas, I'm encouraged by your reply as it implies that what I and others are experiencing is not by intent and therefore should be fixable. I suggest it might elicit a more favourable reaction from customers if the those with greater experience of PF3 were a little less strident in their defence of its many merits. Even Dave seems to have concluded that there is something not quite right, so it seems rather baffling that your testing colleague is not so flexible in his outlook.

I want to use PF3 but I am experiencing issues that currently make that unviable. I have submitted logs of two flights that demonstrate the issue and have not had an explanation as to why. I'm content to wait, but I would have thought it not beyond the wit of even the most dedicated tester to understand that this induces frustration.

Kind regards

Andy
Top
Profile Quote
vololiberista
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 11:12 am
Offline
 
Posts: 980
Joined: Wed May 27, 2009 8:41 pm
Location: LIMZ
 
I have just completed Martin's flight plan exactly as PF3 had generated it. For the entire route I was given correct vectors and correct climbs and correct descents. PF3's fpl profile adequately allows for a descent rate of around 1,700fpm from cruise until ILS capture. My conclusion therefore is that there is nothing wrong with the fpl or with PF3's handling of it. PF3 did exactly what it says on the tin. And did a good job of it too.

I would suggest that FL340 is a little high for such a short flight. I fly a high performance aircraft the VC10 which designed for hot and high take-offs so its climb performance is more than sufficient to get to FL340 quickly. If however you are flying a heavy such as a 767, 777 or 747 then you should reduce your cruise altitude probably by 10,000ft! A jumbo really struggles in anything above 25 celcius.

Pay attention to what ATC is saying. Maintain a listening watch. If the say descend before your TOD then do it. If you expect to pass your TOD without anything from ATC then ask them for a descent.

So here are the logs if Dave wishes to compare them with Martin's
Logs.zip
(250.86 KiB) Downloaded 130 times
FPP.zip
(6.15 KiB) Downloaded 132 times

_________________

[ img ]
Top
Profile Quote
ThomasAH
Post subject: Re: Constantly too late TOD !
Posted: Sat Apr 02, 2016 11:49 am
Offline
 
Posts: 988
Joined: Tue Dec 24, 2013 12:27 pm
 
Some more observations in Martin's last log:
Code: Select all
01/04/2016 16:40:44: 850 - -----------------------------
01/04/2016 16:40:44: 850 - Step Climbs for Waypoint: 3
01/04/2016 16:40:44: 850 - -----------------------------
01/04/2016 16:40:44: 850 -      34000'
01/04/2016 16:40:44: 850 - -----------------------------

01/04/2016 16:42:39: 880 - Checking compliance - Alt: 33660  sWPAlt: 34000  FlightType: 1  ATC_Timer: 0  AltTimer: 0  FSTime: 60159  AptSighted: 0  Handoff: 0

01/04/2016 16:42:39: 900 - TOD recalculated now distance is set to 232 NM
01/04/2016 16:42:39: 920 - ****** Reached TOD ******
01/04/2016 16:42:39: 920 - BPT: 0
01/04/2016 16:42:39: 920 - -----------------------------
01/04/2016 16:42:39: 920 - Step Climbs for Waypoint: 3
01/04/2016 16:42:39: 920 - -----------------------------
01/04/2016 16:42:39: 920 -      15000'
01/04/2016 16:42:39: 920 - -----------------------------

01/04/2016 16:42:43: 700 - Checking compliance - Alt: 33768  sWPAlt: 15000  FlightType: 1  ATC_Timer: 0  AltTimer: 0  FSTime: 60163  AptSighted: 0  Handoff: 0

01/04/2016 17:01:32: 110 - -----------------------------
01/04/2016 17:01:32: 110 - Step Descents for Waypoint: 5
01/04/2016 17:01:32: 110 - -----------------------------
01/04/2016 17:01:32: 110 -      24000'
01/04/2016 17:01:32: 110 -      10000'
01/04/2016 17:01:32: 110 -      8000'
01/04/2016 17:01:32: 110 - -----------------------------

01/04/2016 17:01:35: 860 - Transcript: 'Air India 3205 Descend and maintain Flight Level 240  '
So you reached the TOD calculated by PF3 at 208 NM from the destination (not the 232 NM shown above), but this was before you reached the cruising altitude.
Some things in PF3 are only triggered after the cruising altitude is reached and I think some only at waypoints. It seems PF3 was heavily confused by this situation.

If you could do the climb a little bit faster, or set the cruise altitude a little bit lower, or maybe add some waypoints for PF3 to work with, or maybe fly in an area where PF3 inserts XXX waypoints for control center boundaries, this should already work with the current version of PF3.
Wow, these are many if, ors and maybes, but I assume Dave can find a solution (or at least a workaround) for such situations. But as it is important to not break other parts of PF3 while fixing this, we should let him take the time he needs to make a good decision on how to solve this predicament.

_________________

[ img ]
Top
Profile Quote
Display: Sort by: Direction:
Post Reply   Page 4 of 7  [ 61 posts ]
Return to “PF3-ATC at its best” | Jump to page « 1 2 3 4 5 6 7 »
Jump to:
Board index Delete cookies | All times are UTC+01:00

Powered by phpBB® Forum Software © phpBB Limited

Privacy | Terms