LNAV switch & TOGA

[Tony747-400 44]

Hi

I did a couple of flights yesterday and not sure if this is the correct behaviour of the LNAV switch

 

Before Take Off I arm VNAV & LNAV both switches are lit and shown armed on the FMA on the PFD. When I press the TOGA and start my Take Off roll the LNAV switch is staying lit, VNAV extinguishes. I thought the correct behaviour was for both VNAV & LNAV to extinguish until they come active about 400.

 

If this is incorrect I haven't noticed how long my NGX has been doing this, or anyone have any ideas what maybe wrong?

 

Thanks guys

[squerble 300]

Just to check, how many times do you press TOGA? Do you spool to 40-50%N1 then press TOGA once?

 

Are both FDs turned on, with your side showing the MA light?

 

 

Sent from my iPhone using Tapatalk 2

[rsvit 16]

I have seen this behavior on honeywell MCP. Until VNAV is armed you don't have to worry, ground prearm will work.

[Lek767 37]

I've seen this mentioned on the forums before and believe it to be deemed a bug that will be fixed in SP2. Could be wrong, though.

[Tony747-400 44]

Hi.

Yes I only press the TOGA switch once, I will check that both FD's are on, i know definately my side ( Captains) is on.Everything works correctly with the Autopilot following FMC comands etc,so not too worried. I know one thing, that I didn't run FSX as administrator yesterday, maybe that was the cause. Will experiment more later when back home at the PC.

[hopskip 253]

I'v seen this happen on some airports and not on others. Still haven't figured out why.

 

eg: This unusual behaviour at YSSY rwy 16R or 16L

Normal behaviour at YMML rwy 27.

[Tony747-400 44]

After some experimenting I found my problem to be caused by the particular livery I was using. I checked for failures and used the service feature for that particular livery/aircraft but didn't cure the problem. I then tried a few other liveries and the LNAV button worked how it should do, extinguishes when TOGA is pressed.

[MED1473 18]

Hi! Are you sure it's not dependent on the equipment you're using rather than the livery? It could be one of the options.

Regards

[Tony747-400 44]

Hi! Are you sure it's not dependent on the equipment you're using rather than the livery? It could be one of the options.

Regards

I know it does seem odd, but I have all my liveries set up with the same equipment / displays etc.

I don't think there is an option anyway to change the behaviour if the LNAV switch with TOGA anyway.

 

Seems as it's one off these strange PC bugs that creep in

[simon-flight 0]

Hi,

 

I have the same effect and established its to do with whether the aircraft you are flying has the autopilot set up in the pmdg options in the fmc for 'wings level' or 'heading select' after takeoff. If its wings level the lnav light extinguishes the same as the vnav. If its heading select the lnav light stays iluminataed and hdg sel appears in green in the pfd (probably the wrong name ?) with lnav in white below.

 

So in a way its livery dependent but can be altered

 

Hope this helps,

 

Simon

 

 

 

 

 

 

[Tony747-400 44]

Hi, I have the same effect and established its to do with whether the aircraft you are flying has the autopilot set up in the pmdg options in the fmc for 'wings level' or 'heading select' after takeoff. If its wings level the lnav light extinguishes the same as the vnav. If its heading select the lnav light stays iluminataed and hdg sel appears in green in the pfd (probably the wrong name ?) with lnav in white below.So in a way its livery dependent but can be altered Hope this helps,Simon

Thanks Simon

 

I will have alook through the options on that paticular plane/livery. I do keep the settings the same for all liveries but maybe some how I changed a setting. All my other liveries work fine