How is a NAV ACCURACY check carried out?

There is a need to compare both VOR bearing and DME distance vs BG and DIST.

This can be done on the MCDU PROG page. The progress page will show if proper accuracy is being followed or not. If not, there may be certain changes that should be made so that the goal can be achieved. This is often used by pilots when they are navigating. It also helps them during hard flight situations.

You need to compare both VOR bearing and DME distance vs BG and DIST.