I was wondering what the proper procedure is for changing altitude when the vnav/lnav are engaged? I keep running into goofy problems with the vnav disengaging-- then not wanting to reengage (fmc gives a check alt in mpc message).Also, lets say I enter a route from tucson to san diego. The legs page lists each waypoint/nav aid along with speed and an altitude. Is that the minimum altitude you are supposed to cross that point at, or is that the projected altitude you will be at when you descend? ...okay, almost done with the questions... Lastly, whats the proper procedure for setting the altitude for landing? If I am at 30,000 and need to get to 2000 for an ils approach, do I just tune in 2000 in the mpc and let it descend for me automatically?Thanks!Bill

assuming the LNAV and VNAV is enabledFMC says at T/C "reset MCP alt"you would change MCP altitude to the desired FL and the aircaft begins to descent. you can switch between "PATH" or "SPEED" descent in your FMC. if yor M$ ATC is impatient and you don't want a cancelled IFR flight, push "des now" button on your FMC in the "DES" page. the aircraft will inmediately initiate the descent.thats it. should work. don't ask me if this is a 100% correct procedure in regards to checklist or so. cheers

If you are at FL300 and want to descend to 2000ft, first establish where you want to be at 2000ft... is it over a waypoint? Or will any place along your routing do?If you wish to descend to 2000ft crossing a waypoint, you must enter the constraint in 2 places.In the Legs page, enter "/2000" into the RSK corresponding to the desired waypoint.Then you can see the computed TOD on the ND under Map mode. It's usually more efficient and smoother if you enter 2000ft into the MCP will VNAV is on (this is the second constraint) well before reaching the TOD value.What I usually do is monitor the NM to TOD on the progress page, when it reaches 5 nm to go, I select "DES NOW" on the DES page.If you just want to descend to 2000ft, there are 2 options.A) Use LVL CHG by enter 2000ft on the MCP and pressing the LVL CHG button (obviously).Using VNAV to control a descent can be tricky as the FMC computes the alt values for each waypoint. You can still use it, but selecting 2000ft into the MCP can mean an immediate descent may not happen as VNAV will not descend until reaching TOD. Which is calculated on the computed alt values in the LEGS page.Hope I havent lost you in the last part... feel free to question anything I said above, or just correct me ;) JohnP 2.53 GHZ512 RAMWINXPGFORCE 4 128MB Ti4600http://homepage.eircom.net/~eamonnmca/images/logo_ba.JPGwww.bavirtual.co.uk Senior Captain Simflight.com Staff Reviewerhttp://vatsim.pilotmedia.fi/statusindicato...tor=OD1&a=a.jpg

Thanks gents for the excellent help! I honestly should take more time to read the manuals-- but with finals this week I was just looking for the quick and dirty to get some play time :)-Bill