Reducing speed during descent...

[Guest mia]

Hello!I want to know how to reduce to the Flaps maneuvering speed during a VNAV descent. This is an example:The aircraft is at F350 and has just reached the T/D point, so the aircraft is descending with VNAV mode. Now, we are reaching 4000 feet and we are approaching to the IAF (Initial approach Fix), so I want to reduce the speed in order to extend Flaps. Until now, the aircraft continues descending with VNAV mode to reach the IAF according with the FMC profile... But, How to reduce the speed?, which is the correct way to do it? and What happen with the next altitude constraint based on the FMC?Thanx in advance!!Santiago:)

[cowpatz 243]

Santiago a lot depends on what you put in as speed on the VNAV descent and legs page. In the PMDG model you can press the speed knob and dial in what speed you would like. Just be aware that you may need speed brake to help reduce speed. In the real world when it is time to put out flaps most pilots will change the mode to either FLCH or V/SPD. This will open the speed window and you can then dial in what speed you like and have more direct control over it. For a non precision approach flown in VNAV you can open the speed window and select flap when needed. In order not to arrive at the IAP too quick you can put a speed restriction in on the VNAV descent page. Under the spd trans there is a place for a speed/restr entry. Say for example the IAP altitude was 3000 you could enter in the speed/Restr area something like 200/4000. This would make VNAV recalculate the descent so as to be 200 kts below 4000 ft. This makes the whole non-precision approach more manageable.CheersSteve

[kmanning 12]

>Hello!>>I want to know how to reduce to the Flaps maneuvering speed>during a VNAV descent. This is an example:>>The aircraft is at F350 and has just reached the T/D point, so>the aircraft is descending with VNAV mode. >Now, we are reaching 4000 feet and we are approaching to the>IAF (Initial approach Fix), so I want to reduce the speed in>order to extend Flaps. Until now, the aircraft continues>descending with VNAV mode to reach the IAF according with the>FMC profile... But, How to reduce the speed?, which is the>correct way to do it? and What happen with the next altitude>constraint based on the FMC?>>Thanx in advance!!>>Santiago:)

[altstiff 71]

I find reducing speed before I reach the T/D decent point helps reduce the need for speed brakes.