Assessment of aircraft lateral position and glide path.
The awareness of visual illusions can be supported by an identification of all hazard-airports and/or hazard-runways (in the operator’s network) as a function of the available navaids, visual aids and prevailing hazards.
Hazard Assessment
Approach hazards – and any combination thereof - should be assessed for each individual approach, during the approach and go-around briefing, by reviewing the following elements:
Ceiling and visibility conditions;
Weather:
Wind, turbulence;
Rain showers;
Fog or smoke patches;
Drifting snow or sand;
Snow-covered terrain / runway (white-out phenomenon); and/or,
Sun height over horizon;
Crew experience with airport and airport environment:
Surrounding terrain (i.e., texture); and/or,
Specific airport and runway hazards (runway condition, obstructions, black-hole, off-airport light patterns, …);
Runway approach and visual aids:
Type of approach;
Availability and location of DME with respect to runway threshold;
Let-down aid restriction, if any, such as glide slope unusable beyond a specific point or below a specific altitude;
Type of approach lighting system; and,
VASI or PAPI availability.
Terrain Awareness
When requesting or accepting a visual approach, flight crew should be aware of the surrounding terrain features and man-made obstacles.
At night, an unlighted hillside between a lighted area and the runway threshold may prevent the flight crew from correctly perceiving the rising terrain.
Flying Techniques
Type of approach
At night, when an instrument approach is available, prefer this approach to a visual approach to reduce the risk of accident caused by visual illusions:
ILS approach, with use of VASI / PAPI (as available) for the visual segment; or,
Non-precision approach, supported by a VASI / PAPI (as available).
If / when performing a step-down (i.e., dive-and-drive) non-precision approach, do not descend below the MDA(H) before reaching the visual descent / decision point (VDP) - if defined - even if adequate visual references have been acquired before reaching the VDP.
To prevent going too early to visual references and descending prematurely below the MDA(H), the PF should maintain reference to instruments until reaching the VDP. This provides further protection against visual illusions in hazard conditions.
During a visual or circling approach, if the VASI / PAPI indicates below glide slope level off or climb until the VASI/PAPI shows on-glide-path.
Flight path monitoring
Resist the tendency to pitch down and “duck under”; this is the greatest challenge during the visual segment of the approach, this includes:
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本文链接地址：Flight Operations Briefing Notes Human Performance Visual Il(6)
