ATC: Descend to reach level at (waypoint)

[Xaver]

Hi,

how do i properly execute a descent clearance, where I have to be at a specific level at a given waypoint along the router. Only by mental arithmetic, or is there any system which is able to support? Does the 737-300 do have Altitude Range Arcs on the EHSI (like the NG)? Or could I insert an altitude constraint on the FMC and use VNAV to execute a proper descent? 

Tnx for any tips.

Xaver

Edited November 5, 2020 by xavers

[Litjan]

Hello Xaver,

normally you could enter the altitude restriction on the FMC and the VNAV would do the calculation for you - but this does not work reliably for our plane yet...we are working on it!

For now I recommend the "mental arithmetic" method - the 737-300 also sports the "banana" green range arc that moved dynamically to show you where you will reach the selected altitude if you keep going at the current ground speed and vertical speed (so it is not perfectly accurate, but pretty close).

I also include a reference table on the avitab that you can install for our aircraft (its free) that lets you refine the calculation pretty well.

Here is a video where I show how to use it:

https://youtu.be/hSemWBgRNnE

Cheers, Jan

 

[Xaver]

Great, thanks Jan!