Monitor the correct sequencing of the flight plan at each waypoint and the correct guidance after sequencing the waypoint, particularly after a flight plan revision or after performing a DIR TO:
.
Ensure that the direction-of-turn and the TO waypoint are in accordance with the SID.
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In case of incorrect flight plan sequencing and/or of incorrect lateral guidance, crew should be alert to perform a DIR TO [an appropriate waypoint] or to revert to selected lateral navigation.
Changes in clearances should be fully understood before being accepted and implemented.
For example, being cleared to a lower altitude should never be understood as a clearance to descend (prematurely) below the charted sector or segment minimum safe altitude.
When being radar vectored, make sure that :
.
The controller has clearly identified your radar return by stating “radar contact”;
.
The controller can read obstacle clearance altitudes on his or her radar scope (awareness of minimum vectoring altitude and responsibility for terrain separation);
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The controller does not forget that you are on a radar vector, heading toward high or rising terrain;
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The pilot / controller two-way communication remain effective at all times;
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You maintain your own vertical and horizontal situational awareness; and,
.
You request confirmation or clarification from ATC without delay and in clear terms, in case of any doubt.
To prevent an excessive terrain-closure-rate, consider a maximum vertical speed and reduce this maximum limit with decreasing altitude (e.g., do not exceed – 2000 ft/mn when below 2000 ft AGL and
– 1000 ft/mn when below 1000 ft AGL).
During the final approach segment, the primary attention of PF and PNF pilots should be directed to any required altitude constraint or altitude / distance check prior to reaching the MDA(H) or DA(H).
Terrain Awareness – When and How ?
Page 7
Radio altimeter readings below obstacle clearance levels, listed below, should prompt an immediate altitude and position check:
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Initial approach (from IAF to IF) : 1000 ft AGL;
.
Intermediate approach (from IF to FAF, or at minimum radar vectoring altitude) : 500 ft AGL;
.
Final approach (non-precision approaches, inbound of FAF) : 250 ft AGL.
Unless the airport features high close-in terrain, the RA reading (height AGL) should reasonably agree with the height above airfield elevation (obtained by direct reading of the altimeter if using QFE, or by computation if using QNH).
Preparedness to Go-around
In IMC or at night, immediately respond to any GPWS / TAWS warning.
Be prepared and minded to go-around if the conditions for a safe approach and landing are not met (e.g., unstabilized approach at or below the approach gate / stabilization height).
Circling Approaches
When performing a circling approach, be aware of and stay within the applicable obstacle clearance protected area.
Factors Affecting Terrain Awareness
The following factors often are cited as affecting the horizontal or lateral situational awareness and therefore the terrain awareness.
These factors should be addressed by developing company prevention strategies and lines-of-defense, initiating appropriate actions with state agencies, operational authorities and service providers:
. Aircraft equipment:
. Lack of navigation display with terrain display or radar display with mapping function;
. lack of area navigation (RNAV) capability;
. lack of GPWS or TAWS.
.
Airport environment:
. Night “black hole” and/or rising(sloping) terrain along the approach path;
.
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