Position Fixing

Question 1

A positive radio fix is one determined by the passage of the aircraft over?

ATC AU-507 (5.5)

Answer 1

a NDB; or
a VOR station; or
a DME; or
Is one determined by GPS meeting 
the equipment and pilot requirements;

or

Is one determined by the intersection
of 2 or more position lines which intersect with angles of not less than
45 degrees and which are obtained from NDBs. VORs, Localizers, or DMEs
in any combination.

A position line must be within the rated
coverage of the aid,

with the exception that …

If a fix is determined by position lines from NDBs, the position lines must be within a range of 30 miles
from each of the NDBs