Do you mean what is referred to as a "Dead Reckoning Segment"? This is where the IF would be too distant or at the wrong angle (outside the 90degree or 120 degree angle) and at a greater distance.dead-reckoning segment. In this case you use a DR Fix and the max intercept angle to the localizer from the DR Fix is 45degrees.
A segment of an instrument approach procedure where no track guidance is available between the initial approach segment and the intermediate fix. Where an operational advantage can be obtained, an ILS (instrument landing system) procedure may include a dead-reckoning (DR) segment from a fix to the localizer. The DR track intersects the localizer at 45° and is not more than 10 NM (19 km)
in length. The point of interception is the beginning of the intermediate segment and allows for proper glidepath interpretation.
