Subject:
Deletion of 10 NM Reference Circle From IAP Planview
Background/Discussion:
The 10 NM reference circle depicted on the planview of Instrument Approach Procedures
(IAPs), though intended for scale reference only, has been misinterpreted by pilots, pilot
instructors, ATC and others. Many users are under the impression that the area of the
procedure turn is contained within this circle (Remain within 10 NM). This is not necessarily the
case. Others believe that only data within the circle is drawn to scale. This is not the case – all
data on the planview is drawn to scale unless a scale break, inset box or concentric rings are
used. The 10 NM circle is not (nor has it ever been) depicted on RNAV procedures. Although
the center point on which the circle is predicated is usually the FAF, this is not standardized.
The circle is not a part of the published procedure, is not documented on the source 8260, but is
added to the chart by cartographers.
(The 10NM reference does not appear on the Jeppessen IAPs).
Chart User』s Guide contains the following:
Recommendations:
It is suggested that the 10 NM circle is of limited value, is grossly misinterpreted, causes undo
planview clutter and might be better removed from the charts. This RD supports deletion of the
10 NM circle from all charts except were the use of concentric rings is necessary
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