applicable takeoff or approach should be specified to assure appropriate and necessary crew communications. Responsibilities and assignment of tasks should be clearly understood by crewmembers.
6.1.3. Monitoring. Operators should establish appropriate monitoring procedures for each low visibility takeoff, approach, landing, and missed approach. Procedures should assure that adequate crew attention can be devoted to control of aircraft flight path, displacements from intended path, mode annunciations, failure annunciations and warnings, and adherence to minima associated with DH and AH. Where a "monitored approach" is used, (e.g., where the First Officer is responsible for control of the aircraft flight path by monitoring of the automatic flight system) appropriate procedures should be established for transfer of control to the captain who will be making the decision for continuation of the landing at or prior to Decision Height or Alert Height. Monitoring procedures should not require a transfer of responsibility or transfer of control at a time that could interfere with safe landing of the aircraft. Procedures for calling out failure conditions should be pre-established, and responsibility for alerting other crewmembers to a failure condition should be clearly identified.
6.1.4. Use of the Decision Height or Alert Height. Decision heights are normally used for Fail Passive Category III operations and Alert Heights are used for Fail Operational Category III operations.
Certain exceptions are noted elsewhere in this AC (e.g., use of a Decision Height (DH) due to specific fail operational aircraft characteristic at a runway with irregular pre-threshold terrain). When Decision Heights are specified, procedures for setting various reference bugs in the cockpit should be clearly identified, responsibilities for Decision Height call-outs should be clearly defined, and visual reference requirements necessary at Decision Height should be clearly specified so that flightcrews are aware of the necessary visual references that must be established by, and maintained after passing Decision Height.
When Alert Heights are specified, the operator may elect to use an Alert Height at or below 200 ft. HAT as suitable for procedure or procedures identified for use by that operator.
Procedures should be specified for call-out of the Alert Height and if applicable for conversion of the Alert Height to a Decision Height in the event that the aircraft reverts from Fail Operational to Fail Passive flight control.
The operator should assure that at each runway intended for Category III operations, the radar altimeter systems used to define Alert Height or Decision Height provides consistent, reliable, and appropriate readings for determination of Decision Height or Alert Height in the event of irregular terrain underlying the approach path, or an alternate method should be used. Alert Height or DH may be based on other means (e.g., inner marker) only when specifically approved by FAA. Any adjustments to approach minima or procedures made on final approach should be completed at a safe altitude (e.g., above 500 ft. HAT).
6.1.5. Call-outs. Altitude/Height call-outs should be used for Category III. Callouts may be accomplished by the flightcrew or may be automatic (e.g., using synthetic voice call-outs or a tone system). Typical call-outs acceptable for Category III include a combination of the following:
• "1000 ft." above the touchdown zone,
• "500 ft." above the touchdown zone,
• "approaching minimums,"
• "minimums,"
• altitudes during flare, (e.g., 50, 30, 10) or AFGS mode transitions (e.g., flare, rollout), and
• as appropriate, auto spoiler, reverse thrust deployment and autobrake disconnect.
Calls made by the flightcrew should not conflict with the automatic systems or auto call-outs of the aircraft, and conversely the configuration selected for the aircraft should not conflict with expected callouts to be made by the flightcrew. Compatibility between the automatic call-outs and the crew call-outs must be assured. The number of call-outs made, either automatically, by crew, or in combination, should not be so frequent as to interfere with necessary crew communication for abnormal events.
Also, call-outs should be specified to address any non-normal configurations, mode switches, failed modes, or other failures that could affect safe flight, continuation of the landing, or the accomplish-ment of a safe missed approach. Any use of crew initiated call-outs at altitudes below 100 ft. should assure that the callouts do not require undue concentration of the non-flying pilot on reading of the radar altimeter rather than monitoring the overall configuration of the aircraft, mode switching, and annunciations that might be related to a successful Category III landing. Automatic altitude call-outs or tones are recommended for altitude awareness, at least at and after passing Decision Height or Alert Height.
Operators may make provision for use of crew verbal callouts as a backup, or in lieu of automatic callouts in certain circumstances. It is recommended that operators have a policy addressing procedures to be used when an automatic callout system fails or is inoperative regarding making some or all key callouts manually. Examples of when use of verbal crew callouts may be appropriate instead of or to augment automatic callouts include:
1) When an automatic callout system has failed,
2) When automatic callouts are inoperative through an MEL provision, or
3) When a particular automatic callout is not issued or is masked by another cockpit advisory or crew conversation, or is not heard for some other reason.
6.1.6. Aircraft Configurations. Operational procedures should accommodate any authorized aircraft configurations that might be required for low visibility takeoff or Category III approaches or missed approaches. Examples of configurations that operational procedures may need to accommodate include:
1. Alternate flap settings approved for Category III,
2. Use of alternate AFGS modes or configurations (e.g., Single Land, LAND2),
3. Inoperative equipment provisions related to the minimum equipment list, such as a non-availability of certain electrical system components, inoperative radar altimeter, air data computers, hydraulic systems or instrument switching system components, and
4. Availability and use of alternate electrical power sources (e.g., APU) if required as a standby source.
Procedures required to accommodate various aircraft configurations should be readily available to the flightcrew and the aircraft dispatcher to preclude the inadvertent use of an incorrect procedure or configuration. Acceptable configurations for that operator and aircraft type should be clearly identified so that the pilots can easily determine whether the aircraft is or is not in a configuration to initiate a low visibility takeoff or Category III approach. Configuration provisions must be consistent with, but are not limited to, those provided in the operations specifications for that operator.
6.1.7. Compatibility with Category I and Category II Procedures. The operator should assure that to the greatest extent possible, procedures for Category III are consistent with the procedures for that operator for Category II and Category I to minimize confusion about which procedure should be used or to preclude procedural errors due to pilots reverting to familiar procedures accomplished more frequently such as for Category I. The operator should to the extent practical, minimize the number of procedures that the crew needs to be familiar with for low visibility operations so that, regardless of the landing category necessary for an approach, the correct procedures can be used consistently and reliably.
6.1.8. Flightcrew Response to Non-Normal Events. Takeoff and landing weather minimums are intended for normal operations. When non-normal events occur, flightcrews and aircraft dispatchers are expected to take the safest course of action to assure safe completion of the flight. Using emergency authority, pilots can deviate from rules or polices, to the extent necessary, to minimize the risk of continued flight to a safe landing. In some instances, guidelines are established for particular failure situations, such as failure of required aircraft systems prior to reaching Alert Height.
When procedures or configurations have not been specified, pilots and aircraft dispatchers are expected to use good judgment in making the determination of appropriate configurations or situations to conduct safe Category III operations. The decision to continue an approach or to discontinue an approach must
be made considering all relevant factors of the status of the aircraft, fuel on board, seriousness of the emergency, distance away of other available airports, and the likelihood of changing weather conditions, among other factors. It is not the intent of this AC to attempt to define guidelines for circumstances such as in-flight fire, minimum fuel reserves, or other situations requiring complex judgments of skilled crewmembers.
However, in the case of certain well-defined situations that can be addressed before departure, such as contingency planning in the event of an engine failure, guidelines are provided to assist pilots in making safe and consistent judgments about available alternative courses of action. Specific guidelines for initiation for a Category III approach with an inoperative engine are provided in section 5.17.
Guidelines for other configuration situations may be provided by the normal or non-normal procedure section of the aircraft flight manual or by the operator. Pilots and aircraft dispatchers are expected to be familiar with these guidelines and apply them to the extent practical but may deviate as necessary from those guidelines, to the extent that they consider necessary to assure safe flight and landing. If doubt exists as to the advisability of continuation of an approach or diversion, it is the flightcrews responsibility to exercise their emergency authority to the extent necessary to assure a safe flight.
6.2. Category III Instrument Approach Procedures and Low Visibility Takeoff.
6.2.1. Takeoff Guidance System Procedures. When takeoff minima are predicated on use of a takeoff guidance system meeting the criteria of Section 5.1.3 or Appendix 2, procedures for use of the takeoff guidance system should be identified consistent with the approved AFM, or applicable operational authorization. Procedures should address at least the following items or factors:
• Setup, test, and initialization of the guidance system and NAVAID’s, as applicable
• Roles and responsibilities of the PF and PNF
• Suitable alignment with and tracking of the runway centerline
• Suitable transfer of control between pilots for failures or incapacitation, as applicable
• Suitable response to failures (e.g., engine failure before and after V1, electrical failure, guidance system alerts, warnings, and failures as applicable)
6.2.2. Acceptable Procedures for Category III Approach. Instrument Approach Procedures for Category III may be conducted in accordance with:
1. published 14 CFR part 97 procedures, or
2. approved operations specifications for special procedures, or
3. published foreign or military procedures approved by the FAA, or
4. foreign or military procedures accepted by FAA for specific foreign airports and runways.
6.2.3. Standard Obstacle clearance for approach and missed approach. Advisory Circular 120- 29 as amended provides the standard Category II and III approach and missed approach criteria not otherwise specified in FAA Order 8260.3 (TERP’s). The criteria in AC 120-29 should be applied except where acceptable TERP’s criteria is provided for Category II and III operations using ILS, MLS, GLS or RNP facilities and equipment. Standard obstacle clearance criteria are typically incorporated with published part 97 procedures. Standard criteria used by several foreign authorities based on ICAO PANS OPS may be used where found to be acceptable to the FAA (e.g., JAA approved procedures). Category II and III procedures developed using criteria other than TERPS or PANS OPS are normally issued through operations specifications as special procedures. (See paragraph 6.2.4.)
6.2.4. Special Obstacle Criteria. In certain instances standard obstacle criteria as specified by TERPS may not be appropriate for particular Category III procedures. In such instances alternate criteria acceptable to the FAA may be used as specified in OpSpecs (e.g., RNP criteria).
6.2.5. Irregular Terrain Airports. Irregular terrain airports identified by a part 97 procedure, or by FAA order 8400.8, as amended, must be evaluated in accordance with FAA approved procedures prior to incorporation in operations specifications for use by air carriers operating to Category III minima.
Irregular terrain airport special evaluations should consider each particular aircraft type, the particular flight control system, and may include consideration of particular system elements such as the type of radar altimeters installed or other equipment.
Procedures for evaluation of these airports are provided in Appendix 8.
6.2.6. Airport Surface Depiction for Category III Operations. A suitable airport surface depiction (e.g., airport diagrams) should be available to flightcrews to assure appropriate identification of visual landmarks or lighting to safely accomplish taxing in Category III conditions from the gate to the runway and from the runway to the gate. The Airport depiction should use an appropriate scale with suitable detailed information on gate locations, parking locations, holding locations, critical areas, obstacle free zones, taxi way identifications, runway identifications, and any applicable taxi way markings for designated holding spots or holding areas. Standard depictions provided by commercial charting services are typically acceptable if they provide sufficient detail to identify suitable routes of taxi to and from the runway and gate positions for departure or arrival.
6.2.7. Continuing Category III Approaches in Deteriorating Weather Conditions. The following procedures are considered acceptable in the event that weather conditions are reported to drop below the applicable Category III minima after an aircraft has passed the final approach point or final approach fix, as applicable. (Reference section 121.651.)
• Operations based on a DA(H) may continue to the DA(H) and then land, if the specified visual reference is subsequently established by the pilot no later than the DA(H).
• Operations based on an Alert Height (AH) may continue to the AH and then land, if weather is reported to be at or above minima before passing the AH, or if suitable visual reference has been established by the pilot.
• Operations based on an AH may continue to land regardless of reported weather conditions if equipped with a fail operational rollout system which did not indicate a malfunction prior to passing alert height, and the pilot considers continuation a safe course of action.
Operators requesting amended operations specifications reflecting the procedures described above may have their current operations specifications amended by making application in accordance with paragraph 10.16. New Category III operators should have operations specifications issued reflecting these provisions in accordance with revised standard operations specifications (see samples provided in Appendix 7).
When wind constraints apply to Category III procedures (e.g., an Operation-Specification 15 knot crosswind component limit) the limit is considered to apply to the point of touchdown. If a report of a crosswind component value greater than the limit is received while on approach, an aircraft may continue an approach, but a subsequent wind report indicating winds are within limits or a pilot determination that actual winds are within limits must be made prior to touchdown. Acceptable methods for such a determination may include ATS reports, reports of other aircraft with reliable means of wind determination (e.g., IRS), pilot use of on board IRS or FMS wind readout capability, data link of recent winds, or pilot confirmation of an acceptable visual indication of winds on the surface by a wind sock, wind indicator or equivalent wind indicating device.
When an Airplane Flight Manual or other manufacturer’s reference (e.g., FCOM) references “Maximum wind component speeds when landing weather minima are predicated on autoland operations”, or an equivalent statement, an operator or flightcrew may consider those wind values to apply to “steady state” wind components. Any gust values which exceed the steady state wind limit need not be addressed if the flightcrew determines the gust exceedance can be considered insignificant in magnitude, variable in direction, occasional, or otherwise not applicable (e.g., obviously outdated gust report, winds and gusts reported at a location considered far from the runway or touchdown zone and not applicable, or gusts considered not pertinent during the period of touchdown or rollout).
6.2.8. Low Visibility Taxi Procedures. Low visibility taxi procedures should be adopted for each airport having such procedures. The procedures should be available to pilots in chart form, if applicable, and used. In addition to published Surface Movement Guidance and Control System (SMSGS) airport diagrams and information, the operator should provide:
• Any necessary specific gate identification information to find gates, ramp areas, or lead in vehicles,
• Any necessary information about identification of critical area protection zones or areas,
• Any necessary emergency response information for takeoff, landing, or other emergencies that are different for low visibility operations (e.g., markings or other ways to easily find and identify explosive holding areas in low visibility),
• Information on any known characteristics of the airport where aircraft ground vehicle traffic conflicts, taxi speed, or aircraft wing tip clearance pose unusual difficulty,
• Any other information necessary to facilitate safe operations in very low visibility (e.g., visual references that may be used for operations when standard markings may not be visible due to construction, snow cover).
Provision should be made for both day and night operation, unless operations are only conducted during either night or daylight hours.
Low visibility taxi and ground operations and related training and qualification are addressed in Sections
7.1.1 item 3 and 7.1.3 item 5 for ground training, Section 7.2 for flight training, and Section 8.5 for SMGCS Plans.
6.2.9. Navigation Reference Datum Compatibility (e.g.,WGS-84/Other Datum).
Outside the U.S., it is important for operators using FMS, GPS and RNAV to be aware of, and where necessary, take precautions to address potential differences in the Navigation Data Base (NDB) "reference datum" used by their aircraft's navigation system, and the datum used en route and at destination or alternate airports. Some States specify aeronautical data (e.g., NAVAID locations, runway locations, waypoint locations), including data for instrument procedures, using a reference datum other than the standard WGS-84 datum, or equivalent.
Addressing this difference can be important to preclude significant navigation errors. If not appropriately addressed, aircraft actual position may significantly differ from indicated position when flying in these areas. Aircraft may experience navigation difficulty including:
• Incorrect FMS position updating,
• Incorrect navigation to a waypoint, NAVAID, runway, or other geographic location,
• Violation of airspace or obstacle clearance during approach or missed approach,
• Displacement from the desired flight path, or runway misalignment following completion of an instrument approach, or
• Significant map shift, if FMS position is based on updates from NAVAID(s) referenced to a local datum inconsistent with that of the aircraft's navigation data base.
Also, this issue can be important when flying with FMS using a WGS-84 referenced navigation data base with "GPS updating capability" installed, but not operative (e.g., as for an FMS MEL dispatch, with GPS inoperative, GPS updating inoperative; or GPS updating inhibited).
For Category III procedures, the issue of use of an appropriate Navigation "Reference Datum" principally applies to flying RNAV initial or intermediate approach segments, or missed approach segments. Final approach segments of ILS or MLS procedures typically are not adversely affected by a difference in reference datum because of direct use of the localizer course. GLS or RNP procedures, while depending on specification of an appropriate reference datum for final approach, are otherwise protected from this datum difference through other criteria which assures consistent datum use for procedure development.
Information about the navigation reference datum used in particular locations outside of the United States is typically available on the Internet. An example of a commercial web site containing this information may be found at: http://www.jeppesen.com/wgs84.html Accordingly, when operating outside United States airspace and when WGS-84 is not used locally as the reference datum for NAVAID’s or procedures, or a reference datum equivalent to WGS-84 is not used, operators should take suitable precautions, as described below. These precautions apply to any RNAV segments flown as part of any instrument approach procedure or missed approach procedure (including Category III procedures, if applicable) for:
• FMS equipped aircraft capable of GPS updating, or
• GPS "stand alone" equipped aircraft, or
• FMS equipped aircraft.
a. Aircraft Equipped With FMS Having GPS Updating Capability, or Equipped With "GPS Stand Alone" Navigation Systems.
For operations outside the United States, where the local datum is not WGS-84, or WGS-84 equivalent, or where the operator is uncertain as to whether the local datum is significantly different than WGS-84, the operator should take one or more of the following precautions, as necessary:
1) Verify that the datum is WGS-84, or equivalent,
2) Conduct an assessment of the difference in the datum used, to determine that any difference is not significant for the procedures to be flown,
3) Develop and use special RNAV procedure segments or aeronautical data referenced to WGS-84 or equivalent, as necessary,
4) Manually inhibit GPS updating of the FMS while flying the approach, or segments of the approach affected by the difference in reference datum,
5) Only use FMS or GPS Stand Alone systems to fly pertinent RNAV segments of the approach where it is possible to use other NAVAID raw data to confirm correct aircraft position along the flight path,
6) Conduct simulation verification, or in-flight verification or confirmation of suitable navigation performance,
7) Preclude FMS or GPS use on segments of the approach affected by the difference in reference datum, or
8) Use any other method proposed by the operator, and found acceptable to FAA, to assure that a difference in the NDB Reference Datum from the local datum does not cause loss of navigation integrity.
For GLS or RNP procedures or procedure segments, since the reference datum is consistent with WGS-84 by procedure design, operators of aircraft using GPS updating of FMS, or "GPS Stand Alone" systems for RNAV need not apply the special precautions listed above, unless otherwise advised (e.g., by NOTAM, or equivalent).
b. FMS Equipped Aircraft That Do Not Have GPS Updating Capability.
While possible, FMS equipped aircraft that do not have GPS updating capability may be less likely to experience this particular datum reference difference issue. This is because navigation data bases, local NAVAID’s, and local instrument procedures typically address and resolve datum issues consistently on a local basis, and in a consistent manner within the locally used coordinate frame of reference.
However, even though the datum difference issue may be less likely, it nonetheless may occur.
Precautions should be applied by operators, as necessary, if there is significant doubt as to Navigation Data Base datum differences.
The precautions listed above in item a. should not be interpreted to discourage GPS installation and use.
GPS updating of FMS can significantly increase both navigation accuracy and integrity, and reduce the risk of other types of navigation errors, including map shifts, yielding a significant safety increase.
7. TRAINING AND CREW QUALIFICATION. Training and crew qualification programs pertinent to Category III should include provisions for appropriate ground training, flight training, initial qualification, recurrent qualification, recency of experience, and re-qualification. The operators program should provide appropriate training and qualification for each pilot in command, second in command and any
other crewmember expected to have knowledge of or perform duties related to Category III landing or low visibility takeoff operations (e.g., Flight engineer).
Pilots in command are expected to have a comprehensive level of knowledge with respect to each of the ground training subjects and have performed each of the specified maneuvers and demonstrated skill in accomplishing each of the tasks specified for flight training. Second in command pilots should have a comprehensive knowledge of the subjects specified in the ground training program, and are expected to perform those relevant procedures or maneuvers applicable to the second in command is assigned duties during Category III landing operations or for low visibility takeoff. Other crewmembers are expected to have the knowledge required and the demonstrated skills to perform their assigned duties.
7.1. Ground Training.
7.1.1. Ground System and NAVAIDs for Category III. Ground systems and NAVAID’s are considered to include characteristics of the airport, electronic navigation aids, lighting, marking and other systems (e.g., RVR) and any other relevant information necessary for safe Category III landing or low visibility takeoff operations.
The training and qualification program should appropriately address the operational characteristics, capabilities and limitations of at least each of the following:
1. NAVAID’s. The navigation systems to be used, such as the instrument landing system with its associated critical area protection criteria, marker beacons, distance measuring equipment, compass locators or other relevant systems should be addressed to the extent necessary for safe operations. As applicable, operationally relevant characteristics of NAVAID types to be used should be addressed. For example for ILS or MLS, any characteristics of beam bends, overflight disturbances, beam switchover to secondary transmitters or power sources, flare of the glide slope signal at low altitudes may need to be explained or addressed depending on the characteristics of the particular flight guidance system used. If non ground based systems (e.g., GNSS) are used, any characteristics or constraints regarding that method of navigation, must be addressed (e.g., proper procedure waypoint selection and use, integrity assurance, coping with space vehicle (SV) loss of availability or failure, SV terrain masking).
2. Visual aids. Visual aids include approach lighting system, touchdown zone, centerline lighting, runway edge lighting, taxiway lighting, standby power for lighting and any other lighting systems that might be relevant to a Category III environment, such as the coding of the center line lighting for distance remaining, and lighting for displaced thresholds, stop ways, or other relevant configurations should be addressed.
3. Runway and Taxiways and SMGCS Plans. The runway and taxiway characteristics concerning width, safety areas, obstacle free zones, markings, hold lines, signs, holding spots, or taxi way position markings, runway distance remaining markings and runway distance remaining signs should be addressed. The SMGCS plan use should be addressed as applicable. This should include any
necessary briefings to be conducted and crew coordination, particularly for crash and rescue, evacuation, or other non-normal events, if different for low visibility situations.
4. Weather Reporting. Weather reporting and transmissometer systems, including RVR locations, readout increments, sensitivity to lighting levels set for the runway edge lights, variation in the significance of reported values during international operations, controlling and advisory status of readouts, and requirements when transmissometers become inoperative should be addressed.
5. Facility Status. Facility status, proper interpretation of outage reports for lighting components, standby power, or other factors and proper application of NOTAM’s regarding the initiation of Category III approaches or initiation of a low visibility takeoff should be addressed.
7.1.2. The Airborne System. The training and qualification program should address the characteristics, capabilities, limitations, and proper use of each appropriate airborne system element applicable to Category III landing or low visibility takeoff including the following:
1. Flight Guidance. The flight control system, flight guidance system, instruments and displays and annunciation systems including any associated flight director, landing system and roll out system, or takeoff systems, if applicable. For automatic or manual systems which require crew input for parameters such as inbound course or automatic or manually tuned navigation frequencies, the crew should be aware of the importance of checking that proper selections have been made to assure appropriate system performance.
2. Speed Management. The automatic throttle, FMC or other speed management system, if applicable.
3. Instruments. Situation information displays, as applicable.
4. Supporting Systems. Other associated instrumentation and displays, as applicable, including any monitoring displays, status displays, mode annunciation displays, failure or warning annunciations and associated system status displays that may be relevant.
5. Aircraft Characteristics. Any aircraft characteristics that may be relevant to Category III, such as cockpit visibility cutoff angles and the effect on cockpit visibility of proper eye height, seat position or instrument lighting intensities related to transition through areas of varying brightness visual conditions change. Pilots should be aware of the effects on flight visibility related to use of different flap settings, approach speeds, use of various landing or taxi lights and proper procedures for use of windshield wipers and rain repellent. If windshield defog, anti-ice, or de-icing systems affect forward visibility, pilots should be aware of those effects and be familiar with proper settings for use of that equipment related to low visibility landing.
7.1.3. Flight Procedures and Associated Information.
1. Operations Specification. Pilots and aircraft dispatchers should be familiar with, and properly able to apply, operations specifications applicable to Category III landing or low visibility takeoff.
2. Normal and Non-normal Procedures. Pilots should be familiar with appropriate normal and non-normal procedures including crew duties, monitoring assignments, transfer of control during normal operations using a "monitored approach," appropriate automatic or crew initiated call-outs to be used, proper use of standard instrument approach procedures, special instrument approach procedures, applicable minima for normal configurations or for alternate or failure configurations and reversion to higher minima in the event of failures.
3. Weather and RVR. Pilots and aircraft dispatchers should be familiar with weather associated with Category III and proper application of runway visual range, including its use and limitations, the determination of controlling RVR and advisory RVR, required RVR equipment, appropriate light settings for correct RVR readouts and proper determination of RVR values reported at foreign facilities.
4. Use of DA(H) or Alert Height. Pilots should be familiar with the proper application of Decision Height or Alert Height, as applicable, including proper use and setting of radar altimeter bugs, use of the inner marker where authorized or required due to irregular underlying terrain and appropriate altimeter setting procedures for the barometric altimeter consistent with the operators practice of using either QNH or QFE.
5. Use of Visual Reference. Pilots should be familiar with the availability and limitations of visual reference encountered for taxi, takeoff, and approach.
Approach visual reference limitation information should at least address aircraft geometry limitations on visual reference, actions to take with loss or partial loss of visual reference, risks of inappropriate use of visual reference, and necessary visual references for continuation after Decision Height, if a Decision Height is applicable. Issues listed in section 6.2.7 above for continuation or discontinuation of an approach in deteriorating weather conditions should be comprehensively addressed.
Pilots should be familiar with procedures for an unexpected deterioration of conditions to less than the minimum visibility specified for the procedure during an approach, flare or roll out including the proper response to a loss of visual reference or a reduction of visual reference below the specified values when using a Decision Height and prior to the time that the aircraft touches down. The operator should provide some means of demonstrating the expected minimum visual references that occur on approach when the weather is at acceptable minimum conditions, and the expected sequence of visual queues during an approach in which the visibility is at or above the specified landing minimums. This may be done using simulation, video presentation of simulated landings or actual landings, slides or pictures showing expected visual references, computer based reproductions of expected visual references, or other means acceptable to the FAA.