Thanks for your help. Solved the VNAV problem. It wasn't lack of FMC setup but rather I'm using the Honeywell ( not Collins) MPC and everything works perfect. Did a flight from KSEA to KSFO fully automated with no surprises or problems. VNAV arms and engages every time if the Honeywell unit is used from the start.

I had the same problem .. I solved it by setting both FD (cap & FO) .. so VNAV will arm in ground ..

Why are you resurrecting a two-year-old thread?

I'm having the same problem.  How do you choose between the Honeywell and Collins MCP and how do I know which is which?

 

Gnacino

I've found how to switch the MCP.  I'm going to try the Honeywell later this evening and see if I can engage the VNAV.

 

Gnacino

Fired it up with the Honeywell and no joy. Double checked the fmc entries and their rite on. I forgot to mention in my first post, the vr speeds don't transfer to the pfd.

Is anyone else other than the original poster having this problem? The original post is two years old and there is no supportive answers.

 

Gnacino

Fired it up with the Honeywell and no joy. Double checked the fmc entries and their rite on. I forgot to mention in my first post, the vr speeds don't transfer to the pfd.

Is anyone else other than the original poster having this problem? The original post is two years old and there is no supportive answers.

 

Gnacino

Did you do the tutorial flight?

Check the PMDG Knowledge Base: http://support.precisionmanuals.com/KB/a99/v-speeds-dont-show-on-pfd-speed-tape-vnav-wont-arm-engage.aspx

 

But the whole point of VNAV, Vertical Navigation, is that it should calculate when the aircraft climbs and decends, how fast it does this, and it shoudl do this regardless of what altitude the MCP is in. In the legs section, it shows the altitudes that the aircraft should be at while pasing through every waypoint. If VNAV requires the changing of the MCP input, it is no different than flight level change. VNAV is supposed to work somewhat liek an ILS system, where it descends on a pre-determined path, not by manual input. Because if I want to be at say 8,500' for the FAITH intersection for an ILS into SFO's Rwy 28L, it should bring me to that altitude on time, rather than require me put in 8,500' then put in 7,000' feet for DIVEC when I start the ILS.

The FMC not descending the aircraft below your MCP set altitude is a safety feature built into the NGX and every other aircraft as far as I'm aware of. ATC will usually implement altitude restrictions at various points and usually does not mirror what is programmed into the FMC. The FMC uses many variables when calculating the VNav path including aircraft fuel, pax, cargo loads, enroute winds aloft, selected waypoints, etc.

Yes, I did start up the tut 1 and when I get to the takeoff ref page to transfer the v speeds to the right on the fmc, they transfer on the fmc but they don't go on the pfd. Also the vnav does not engage and it does not show up in white in the pfd. I tried both the Collins and the Honeywell.

The knowledge base you refer to just implicates that something was not entered right in the perf init page. No help! I must have done it line by line at least ten times today. All I want to do is fly. I can get it up an it will follow the route with lnav, but cannot engage the vnav even at cruise altitude.

1. Did you press the EXEC button after entering the PERF INIT data, as the knowledge base article suggests?

2. Are *both* F/D switches turned on?

Yes and yes.

 

Gnacino

Maybe it's best to record your preflight and upload it to YT. We can guess whole year without any success.

I did what I was postponning, uninstall/reinstall.  All went well and everything is working as it should.  Doing my tut 1 flight now, getting ready for the descent and approach to Schipol.  I'll do a couple more flights in the US, then I'll tackle tut 2;)

 

Gnacino

try to make sure you have a SID in the FMC, Runway, Takeoff Data etc. entered into the FMC. Worst comes to worst, just engage it after takeoff, it isn't a big deal I don't think..