How to calculate time and distance to NDB and VOR stations

NDBs

TIME: In order to calculate the time to NDB stations you need the amount of time in seconds and the number of degrees of relative bearing change.

Formula
Time to NDB (in minutes) = time (in seconds) / degrees of relative bearing change

DISTANCE: In order to calculate the distance to NDB stations you need the time in minutes (calculated above) and your ground speed (GS).

Formula
Distance to NDB (in NM) = GS (in KTs) * Time to NDB (in minutes) / 60

VORs

TIME: In order to calculate the time to VOR stations you need the amount of time in seconds and the number of radials crossed.

Formula
Time to VOR (in minutes) = time (in seconds) / number of radials crossed

DISTANCE: In order to calculate the distance to VOR stations you need the time in minutes (calculated above) and your ground speed (GS).

Formula
Distance to VOR (in NM) = GS (in KTs) * Time to VOR (in minutes) / 60

Conclusion

Calculating the time and distance to NDBs and VORs is identical except that you use relative bearing change for NDBs and number of radials crossed for VORs. Remember that when calculating distance you are always going to multiply speed and time.