Runway Field Clearance Floor - Honeywell EGPWS MK V Pilot's Manual

Runway
Field
Clearance
Floor
Terrain
Look Ahead
Alerting
060-4241-000 • Rev. D - March 2000
MK V & MK VII EGPWS Pilot Guide
In -210-210 and later versions, a Runway Field
Clearance Floor feature is included. This is similar to
the TCF feature except that RFCF is based on the current
aircraft position and height above the destination
runway, using Geometric Altitude (in lieu of Radio
Altitude). This provides improved protection at
locations where the runway is significantly higher than
the surrounding terrain as illustrated below.
TCF and RFCF alerts result in illumination of the EGPWS
caution lights and the aural message "TOO LOW TERRAIN".
The audio message is provided once when initial envelope
penetration occurs and again only for additional 20%
decreases in Radio Altitude. The EGPWS caution lights will
remain on until the TCF envelope is exited.
Another enhancement provided by the internal terrain
database, is the ability to look ahead of the aircraft and detect
terrain or obstacle conflicts with greater alerting time.
RFCF Alert Envelope
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