FMC Legs Page manual speed entry

[MattNeville 0]

Hello together,

 

is it possible to enter a speed restriction manually in the legs page without entering an alt restriction? If i try like "250/" ill get an "invalid entry" message.

 

Matt Neville

[CaptKornDog 284]

No, you need an altitude entry also to pair with it. You could use another vertical mode or speed intervene.

[MattNeville 0]

Thanks for the fast reply. It was theoretical for descent planning before TOD. For example to have a fixed speed at the beginning of a procedure turn that is not mandatory in the selected procedure. Because sometimes this leads to excessive use of speed brakes because the standard speed is to high for the turn and the TOD calculation is using the standard speed (which is 240) in this case (even if i use speed intervene).

[CaptKornDog 284]

Thanks for the fast reply. It was theoretical for descent planning before TOD. For example to have a fixed speed at the beginning of a procedure turn that is not mandatory in the selected procedure. Because sometimes this leads to excessive use of speed brakes because the standard speed is to high for the turn and the TOD calculation is using the standard speed (which is 240) in this case (even if i use speed intervene).

 

You can use OFFPATH DES for planning, too, in clean and dirty/speedbrake configurations.  Or try different cost indexes, different SPD/RESTRs on the DES page, or simply try DES NOW a few miles early.

[3-2-1-Now 126]

Just use speed intervention - that will get you what you want. I suggest descending a little earlier in order to decel at the bottom of the descent (unless it is supposed to be a continuous descent, in which case you may have no option but toi use speed brakes, which contrary to popular belief is perfectly OK to do!).

 

Best regards,

Robin.

[MattNeville 0]

Thanks guys! Your suggestions sound great. I'll try them. I know, descent planning is some kind of science and at the moment i'm not quite bad in it. But always want to go as close as possible to the real thing. Of course it's a simulation and has it's limitations :-)

 

Matt

[777simmer 117]

It is correct that you can not enter a speed restriction only, it has to be a speed/altitude pair.....However.....;-)

 

Suppose you have a point in the legs page where the FMC forcasts you will pass at 250kt and 4700ft.

If you want to pass here at 220kt....you can enter for example 220/2000A.

You will then pass this point at 220kt but you have left your altitude flexible.

[MattNeville 0]

Hi Rob,

 

thats a great idea, thanks! Now i have an easy solution.

 

Matt

[florismulock 2]

why cant i post anymore blogs (ony have 3)

 

any way it is related to this supject so hope you dont mind.

 

when i enter my route for instance ( ehrd to eham) the 737 and the 777 does not follow the speeds in the leg page. strange thing is that i didn't update a thing but never had this problem it always followed the speed (i have the fmc speed on so it shouldwork).

 

now it only works (though it does not follow the speeds in the leg page) by adjusting the climb, cruz and desc by selecting these on the fmc (the desc etc buttons).   

 

could someone help me out?

but airplanes are fully updated (737 was updated years ago have the latest update)