Airlines, Aviation Norms, General Aviation, Regulations

Approach Landing Accident Reduction.

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Inadequate professional judgment/airmanship was a causal factor in 74 percent of the accidents and serious incidents;

Failure in CRM (crew coordination, cross-check and backup) was a causal factor in 63 percent of the events.

Incorrect interaction with automation was a causal factor in 20 percent of the events.

Golden Rules for Abnormal Conditions and Emergency Conditions.

The following golden rules may assist flight crews in their decision making in any abnormal condition or emergency condition, but particularly if encountering a condition not covered by the published procedures.

Understand the Prevailing Condition before taking Decision.

Incorrect decisions often are the result of incorrect recognition of the prevailing condition and/or incorrect identification of the prevailing condition.

Assess Risks and Time Pressures.

Take time to make time when possible (e.g., request a holding pattern or radar vectors).

Evaluate the Available Options.

Weather conditions, crew preparedness, type of operation, airport proximity and self-confidence should be considered in selecting the preferred option.

Include all flight crew members, cabin crew members, ATC and company maintenance technicians, as required, in this evaluation.

Match the Response to the Condition.

An emergency condition requires immediate action (this does not mean rushed action), whereas an abnormal condition may tolerate a delayed action.

Consider All Implications, Plan for Contingencies.

Consider all the aspects of continuing the flight through the landing.

Manage Workload-Priortise.

Adhere to the defined task sharing for abnormal/emergency conditions to reduce workload and to optimize crew resources.

Use the AP and A/THR to alleviate PF workload.

Use the proper level of automation for the prevailing condition.

Errors in using automatic flight systems (AFSs) and insufficient knowledge of AFS operation have been contributing factors in approach-and-landing accidents and incidents, including those involving controlled flight into terrain.

Visual Illusions.

The absence or the loss of visual references is the most common primary causal factor in ALAs involving CFIT.

These accidents result from:

Descending below the minimum descent altitude/height (MDA[H]) or decision altitude/height (DA[H]) without adequate visual references or having acquired incorrect visual references (e.g., a lighted area in the airport vicinity, a taxiway or another runway).

Continuing the approach after the loss of visual references (e.g., because of a fast-moving rain shower or fog patch).

Visual approaches at night typically present a greater risk because of fewer visual references, and because of visual illusions and spatial disorientation.

It has been found that disorientation, visual illusions were a causal factor in 21 percent of the 76 ALAs and serious incidents, and that poor visibility was a circumstantial factor in 59 percent of the accidents and incidents.

The following weather conditions can create visual illusions:

Ceiling and visibility (vertical, slant and horizontal visibility).

Flying in light rain, fog, haze, mist, smoke, dust, glare or darkness usually creates an illusion of being too high.

Shallow fog (i.e., a fog layer not exceeding 300 feet thickness) results in a low obscuration and in low horizontal.

When on top of a shallow fog layer, the ground (or airport and runway, if flying overhead) can be seen; but when entering the fog layer, forward visibility and slant visibility are lost.

Entering a fog layer also creates the perception of a pitch-up, which causes the pilot to respond with a nose- down correction that steepens the approach path.

Flying in haze creates the impression that the runway is farther away, inducing a tendency to shallow the glide path and land long.

In light rain or moderate rain, the runway may appear indistinct because of the “rain halo effect,” increasing the risk of misperception of the vertical deviation or horizontal deviation during the visual segment (the segment flown after transition from instrument references to visual references).

Heavy rain affects depth perception and distance perception.

Rain on a windshield creates refraction effects that cause the crew to believe that the aircraft is too high, resulting in an unwarranted nose-down correction and flight below the desired flight path.

In daylight conditions, rain diminishes the apparent intensity.

To guard against the adverse effects of visual illusions, flight crews should be aware of all weather factors.

Be aware of surrounding terrain and obstacles.

Assess the airport environment, airport and runway hazards  and adhere to defined PF-PM task-sharing after the transition to visual flying including monitoring by the PF of outside visual references while referring to instrument references to support and monitor the flight path during the visual portion of the approach

Monitoring by the PM of head-down references while the PF flies and looks outside, for effective cross-check and backup.

To manually fly a safe go-around, adhere to the three- golden rule, Aviate, Navigate, and Communicate.

Set and maintain the pitch-attitude target.

Set and check go-around thrust; and check

The aircraft performance, positive rate of climb, airspeed at or above VREF, speed brakes retracted, radio-altimeter indication and barometric-altimeter indication increasing, wings level, gear up, flaps as required.

While conducting the go-around, adherence to the defined PF- PM  task-sharing and the optimum use of crew resource management (e.g., for monitoring flight parameters and calling any excessive flight parameter deviation) are of paramount importance.

The manual go-around technique must minimize the initial altitude loss and prevent an excessive nose-up pitch attitude by following FD pitch commands, not exceeding the ultimate pitch attitude applicable to the aircraft type.

EGPWS/TAWS

The following should be emphasized when discussing CFIT awareness and response to GPWS/TAWS warnings.

Situational awareness must be maintained at all times.

Preventive actions (ideally) must be taken before a GPWS/TAWS warning;.

Response to a GPWS/TAWS warning by the pilot flying (PF) must be immediate.

The PM must monitor and call the radio altitude and its trend throughout the terrain-avoidance maneuver.

The pull-up maneuver must be continued at maximum climb performance until the warning has ceased and terrain is cleared (radio altimeter).

Wet and Contaminated Runways.

Conditions associated with landing on a wet runway or a runway contaminated by standing water, snow, slush or ice requires a thorough review before beginning the approach.

The presence on the runway of water, snow, slush or ice adversely affects the aircraft’s braking performance by reducing the friction force between the tires and the runway surface and creating a layer of fluid between the tires and the runway, which reduces the contact area and leads to a risk of hydroplaning.

Directional control should be maintained on a contaminated runway by using the rudder pedals and differential braking as required.

Nose wheel steering should not be used at speeds higher than taxi speed because the nose wheels can hydroplane.

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