OnCourse Software

Good day.
I normally create a flight plan using PFPX and export it to PMDG 777 and PF3 in the correct formats. When I compare the route in the PMDG 777 CDU and in PF3, the plans are identical with waypoints and respective altitudes. When approaching the destination airport, the PMDG 777 will descend to follow the altitude settings in the FMC,, but PF3 keeps on "nagging" me to climb back to my original cruising altitude of FL370. I have checked the flight plan in PF3 and it is the same as the FMC. Why does PF3 not recognize the altitudes in the flight plan? Only when on finals will it stop "nagging" and then clears me for approach. But it nags continuously during descent when following the FMC altitudes.

Regards,

Peter Webber.

Peter Webber wrote:

Good day.
When approaching the destination airport, the PMDG 777 will descend to follow the altitude settings in the FMC,, but PF3 keeps on "nagging" me to climb back to my original cruising altitude of FL370.

Peter Webber.

You need to attach the log in zip form so that we can check it out. Having said that why are you following the FMC and not ATC instructions (isn't that the whole point of having ATC)? ATC have no idea of TODs etc unless they are specifically part of the flight plan. Even then there is a built in leeway of 60 arc minutes. i.e. 1 deg lat/long.

When you fly with ATC you follow their instructions and not your FMC. The FMC is just a guide. If it is really important to descend the moment the FMC tells you then you request descent from ATC.

As Nicholas pointed out you should be following what ATC tells you. Your FMC TOD point is calculated basis cost index and wind, and is the most economical point to begin descent basis the information you have input. In the real world pilots are subject to ATC who may descend you earlier or later than your calculated point, of which they know nothing about, and care even less.

As Nicholas said you do have the option to request a lower altitude if you are past your TOD point and fear you may not get down in time, and that will start the trigger for further descents from ATC. But generally, just wait for instructions.

You can, when setting up your flightplan in PF3, ensure you have your cruise FL set at one waypoint and a lower altitude set for the next. This will mean you will be descended sometime after the former waypoint is reached.

pschlute wrote:

As Nicholas pointed out you should be following what ATC tells you. Your FMC TOD point is calculated basis cost index and wind, and is the most economical point to begin descent basis the information you have input. In the real world pilots are subject to ATC who may descend you earlier or later than your calculated point, of which they know nothing about, and care even less.

As Nicholas said you do have the option to request a lower altitude if you are past your TOD point and fear you may not get down in time, and that will start the trigger for further descents from ATC. But generally, just wait for instructions.

You can, when setting up your flightplan in PF3, ensure you have your cruise FL set at one waypoint and a lower altitude set for the next. This will mean you will be descended sometime after the former waypoint is reached.

Thanks for all the info..will give it a try. As I said earlier, the flight plan when displayed in PF3 has the exact lower altitude settings at each waypoint as displayed on the FMC. I've tried following ATC and it keeps me at FL370 until it's too late to descend..

Peter Webber wrote:

pschlute wrote:

As Nicholas pointed out you should be following what ATC tells you. Your FMC TOD point is calculated basis cost index and wind, and is the most economical point to begin descent basis the information you have input. In the real world pilots are subject to ATC who may descend you earlier or later than your calculated point, of which they know nothing about, and care even less.

As Nicholas said you do have the option to request a lower altitude if you are past your TOD point and fear you may not get down in time, and that will start the trigger for further descents from ATC. But generally, just wait for instructions.

You can, when setting up your flightplan in PF3, ensure you have your cruise FL set at one waypoint and a lower altitude set for the next. This will mean you will be descended sometime after the former waypoint is reached.

Thanks for all the info..will give it a try. As I said earlier, the flight plan when displayed in PF3 has the exact lower altitude settings at each waypoint as displayed on the FMC. I've tried following ATC and it keeps me at FL370 until it's too late to descend..

What is your a/c preset in PF3? For a jet transport 2,000fpm climb, 2,500fpm descent and Approach speed 160 IAS. You may have a waypoint too close to your destination. Thus causing you to descend too late. Post your fpl here with altitude restrictions and we'll have a gander.

vololiberista wrote:

Peter Webber wrote:

pschlute wrote:

As Nicholas pointed out you should be following what ATC tells you. Your FMC TOD point is calculated basis cost index and wind, and is the most economical point to begin descent basis the information you have input. In the real world pilots are subject to ATC who may descend you earlier or later than your calculated point, of which they know nothing about, and care even less.

As Nicholas said you do have the option to request a lower altitude if you are past your TOD point and fear you may not get down in time, and that will start the trigger for further descents from ATC. But generally, just wait for instructions.

You can, when setting up your flightplan in PF3, ensure you have your cruise FL set at one waypoint and a lower altitude set for the next. This will mean you will be descended sometime after the former waypoint is reached.

Thanks for all the info..will give it a try. As I said earlier, the flight plan when displayed in PF3 has the exact lower altitude settings at each waypoint as displayed on the FMC. I've tried following ATC and it keeps me at FL370 until it's too late to descend..

What is your a/c preset in PF3? For a jet transport 2,000fpm climb, 2,500fpm descent and Approach speed 160 IAS. You may have a waypoint too close to your destination. Thus causing you to descend too late. Post your fpl here with altitude restrictions and we'll have a gander.

Hi...just performed a flight FACT-FALE using PFPX for flight planning purposes...as suggested, i requested descent with PF3 at TOD as indicated on the FMC. and PF3 performed flawlessly! I realise now I must request the descent and not wait for instructions...

Peter Webber wrote:

vololiberista wrote:

Peter Webber wrote:

Thanks for all the info..will give it a try. As I said earlier, the flight plan when displayed in PF3 has the exact lower altitude settings at each waypoint as displayed on the FMC. I've tried following ATC and it keeps me at FL370 until it's too late to descend..

What is your a/c preset in PF3? For a jet transport 2,000fpm climb, 2,500fpm descent and Approach speed 160 IAS. You may have a waypoint too close to your destination. Thus causing you to descend too late. Post your fpl here with altitude restrictions and we'll have a gander.

Hi...just performed a flight FACT-FALE using PFPX for flight planning purposes...as suggested, i requested descent with PF3 at TOD as indicated on the FMC. and PF3 performed flawlessly! I realise now I must request the descent and not wait for instructions...

Hi,

With which exact command please ?

Regards,

Richard Portier

Just ask for a descent to a lower cruise altitude.

Hi,

With which exact command please ?

Regards,

Richard Portier[/quote]


Using Hotkey "L" to request a lower cruise altitude...

Peter Webber wrote:

Hi,

With which exact command please ?

Regards,

Richard Portier

Using Hotkey "L" to request a lower cruise altitude...[/quote]

Thank you, I also use this command, I thought there was a specific command I was unaware of...

Regards,

Richard Portier