VNAV and the 737

[engwerda 0]

I love the 737NG for FS9 but I find it hard to slow down even if I descend carefully and before the td point just using the VS. I have given up on a VNAV descent as it seems to go into the red on the way down no matter what I do. I tried setting sensible limits in the LEGS page (eg - 170/5000) etc but even so I still finish up high over the threshold and usually have to go around. I disconnect the AT at 1000 AGL and the AP at five hundred but it is rarely what you could call a balanced approach. I usually land (?) with less than 5000kgs of fuel - would this make a difference if I carried a bit more? I don't have this problem with the 744 which seems to to be much more VNAV friendly.Gerry

[downscc 1,327]

For the reasons you describe, I (and many others) do not use VNAV in the terminal area. In fact, I don't use it at all for descent and arrival. I use MCP SPD and VS to control things and it works very well. I keep the LEGS screen up on the FMC and watch the both the next constraint and the one following it, often putting the green arc on the fix I'm descending towards and adjusting VS (vertical speed).The other thing is speed control.. I like to get the 737 slowed down to 170 by about 5 nm before FAF, which gives me plenty of time to do the multiple things that need done by the FAF such as slow to flaps 15 and gear and adjust speed and VS to arrive smoothly on the GS.Try this technique, I think you be happy with it. I've read from real 737 pilots that they don't use VNAV for arrivals either.

[Guest sparksnmagic]

I've wrestled that bear as well, but with a few adjustments, I've had some successes. Planning needs to start at or before the 50nm T/D point. Use ActiveSky to get the weather at your destination, and then:1) in the *DES* screen, L2, put /280 in L2 for target descent speed2) in your *DES* 8) Disengage autopilot and speed hold on short final.So far, so good. A lot of typing -- I hope it works for you.