A Simplified Directional Facility (SDF) provides a final approach course similar to with that of the ILS localizer, although it is not as precise as the Localizer. It does not provide glide slope information.
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The approach techniques and procedures used in an SDF instrument approach are essentially the same as those employed in executing a standard localizer approach, except the SDF course may not be aligned with the runway and the course may be wider, resulting in less precision.
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SDF is not explicitly mentioned in PANS-AIM. Hence, in it is noct not covered in this coding guidelines.
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