Still wondering
Same for us, some of our new 737ng has dme update selected off by default in fmc.
If it is for rnav rnp operation it doesn't make sense, vor update must be set off also in this case. Dme/dme update is more precise than vor/vor
A captain told me that new NG has only one dme receiver that is why it is off by default. ( arguing with gps it is not nedded ... )
He told me also that it is all automatic and with vor update only it will also use the dme if avalaible.
Any enlightenment about this subject ?
I am often overflying areas with gps jamming so I am concerned. Generally jamming last for 10 min and our rnp increase but still around 0.5
Last edited by zoom33; 6th Jan 2017 at 14:44.