Factors in Non-Precision Approaches
Training feedback and return on in-service experience indicate that the following adverse factors and errors are involved frequently in non-precision approaches:
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Use of incorrect or outdated instrument approach charts;

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Late aircraft descent preparation;

.  
FMS navigation accuracy not checked;

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FMS flight plan not correctly setup;

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Navaids not correctly tuned (frequency, identification or course);

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Incomplete briefing;

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Incorrect choice of autopilot modes;

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Incorrect entry of autopilot or autothrottle targets;

.  
Inadequate monitoring of raw data;

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Absence of cross-check and/or ineffective back-up by PF and PNF;

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.  
Inaccurate tracking of final approach course when using the selected heading (or track) mode;

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Late aircraft configuration;

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Final approach speed not stabilized at FAF;

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Failure to account for prevailing head wind component when computing the vertical speed target for the final constant-angle descent segment;

.  
Incorrect identification of FAF (or final descent fix);

.  
Go-around altitude not timely set;

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Premature descent below the next step-down altitude (if multiple step-downs) or below the MDA(H); and,

.  
Absence of identification or timing (as relevant) of the VDP or MAP.

Summary of Key Points
The successful preparation and conduct of a non-precision approach should include the following key points:
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Determining the type of guidance to be used;

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Preparing the FMS, as applicable;

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Completing a descent-and-approach briefing;

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Planning aircraft configuration setup;

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Monitoring the descent profile;

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Managing the aircraft energy during intermediate and final approach;

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Not descending below an altitude before reaching the next step-down fix;

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Determining the correct flight path angle (and/or vertical speed) for the final descent segment;

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Beginning the final descent at the exact final descent fix;

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Maintaining the correct flight path angle (and or vertical speed) during the final descent segment;

.  
Acquiring and announcing visual references;

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Calling the decision to land or go-around;

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Not descending below the MDA(H) before reaching the VDP;

.  
Being prepared and minded to go-around.

Associated Briefing Notes
The following Briefing Notes provide expanded information to supplement the above discussion:
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1.1 - Standard Operating Procedures,

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1.4 - Standard Calls,

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4.2 - Energy Management During Approach,

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7.1 - Flying Stabilized Approaches,

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7.3 - Acquisition of Visual References.

Regulatory References
.  
ICAO – Procedures for Air navigation Services – Aircraft Operations (PANS-OPS, Doc 8168), Volume I – Flight Procedures.

.  
ICAO – Manual of All Weather Operations (Doc 9365).

.  
FAA Special Notice to Airmen AFS-420 (11/26/99).

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Introduction
The transition from instrument references to visual references is an important element of any type of instrument approach.
Some variations exist in airline operating philosophies about task sharing for:
　
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