CAT II/III Workshop

Flight Operations View

CAT II/III Flight Operations View

• General Concepts ICAO/JAA/FAA

• Approval Process– Aircraft Requirements

– Aerodrome Requirements

– Air Operator

CAT II

• CAT II DH<200 (60m)>=100(30m) and RVR >= 1200ft (350m) (JAA 1000 (300JAA 1000 (300))

• Sufficient visual reference for a manual landing

• Equivalent level of safety by; of safety by;– airborne equipmentairborne equipment– ILS FacilityILS Facility

CAT II

• Equivalent level of safety by:– visual aids– flight crew training/procedures– ATC procedures– aircraft maintenance– airfield maintenance– criteria for obstacle clearance

CAT III

• ICAO/FAA - CAT IIIA DH <100(30m) or no DH and RVR >= 700ft (200m) (JAA always DH)

• ICAO/FAA - CAT IIIB DH <50ft (15m) or no DH RVR < 700ft (200m) not <150ft (50m) (JAA 250ft(75m))

• ICAO/FAA - CAT IIIC 0/0 (No JAA)

CAT III

• Not sufficient references to permit visual landing• Minimum to allow pilot to decide whether aircraft

will land in touchdown zone (CAT IIIA) and ensure safety during roll-out (CAT IIIB)

• Desired level of safety achieved with more stringent requirements

DH/DA

• Decision altitude/height (DA/H) - is the wheel height above the runway elevation by which a go-around must be initiated unless adequate visual reference has been established and the aircraft position and approach path have been assessed as satisfactory to continue the approach and landing in safety (JAA)

Decision Height

• JAA - for CAT II and CAT IIIA the visual reference to contain not less than a 3 light segment

• JAA - CAT IIIB visual reference to contain one centreline light

Alert Height

• Alert Height - height above runway based on the characteristics of the aeroplane and its fail operational automatic landing system, above which a CAT III approach would be discontinued and a missed approach initiated if a failure occurred in one of the redundant parts of the automatic landing system, or in the relevant ground equipment

Alert Height• Fail-operational automatic landing system - if in

the event of a failure, the approach, flare and landing can be completed by the remaining part of the automatic system.

• Fail-passive automatic landing system - in the event of a failure there is no significant deviation of aeroplane trim, flight path or altitude but the landing will not be completed automatically.

Alert Height

• Go-around above Alert Height for failures (AFM) affecting fail operational system

• Below Alert Height continue except for Autoland warning

• Height evaluated during certification - typically 100 - 200feet

• Operators can select lower Alert Height

RVR

• Runway Visual Range - range over which a pilot of an aircraft on the centreline of the runway can see the runway surface markings or the lights delineating the runway or identifying its centreline

• Transmissometers strategically located• Three basic portions of runway - the touchdown

zone (TDZ), the mid-runway portion (MID) and the rollout portion or stop end

RVR

• For CAT II TDZ required

• For CAT III TDZ and Mid required

• For lowest weather FAA requires all

• For CAT III with no DH JAA require only one

• RVR is not the Slant Visual Range (SVR) seen by the pilot

RVR Minima

• Pilots require 1-3 seconds to establish visual contact• To establish lateral position pilots required to see not

less than three lights• To maintain lateral most pilots require to be able to see a

lateral element of ground pattern• Vertical plane - see a point which has low apparent

movement relative to the aircraft

RVR Minima

• Establish an RVR to to be associated with that DH to ensure required visual reference is established

• Correlation between visual segment SVR - RVR

• Eye position is important

• Landing lights can obscure required visual reference in CAT III

Minimum Approach Break-off Height

• MABH is the lowest height above ground measured by radio-altimeter such that if a missed approach is initiated without external references:– in normal operation, the aircraft does not touch the

ground during the procedure

– with an engine failure it can be demonstrated that an accident is extremely improbably

Minimum Approach Break-off Height

• Used by JAA but being phased out

• Replaced by minimum DH or indication in AFM of altitude loss during automatic go around - either MABH or altitude loss in AFM can be use to determine minimum DH in CAT III operation

Types of Minima

• Airfield Operating Minima - established in accordance with aerodrome OCH

• Operator Minima - Lowest minima approved by authority for use by an air operator

• Crew Minima - lowest for a crew depending on their qualification/experience

• Aircraft minima - demonstrated during aircraft certification and found in the AFM

Approval Process

Aircraft

Flight Crew Air Operator

Aerodrome

Safety

Regulatory Approval

Aircraft requirements Airfield requirements

CAT II/III cert ification CAT II/III facilities

Operator’s duties

Crew training

Flight Procedures

Maintenance programme

Airf ield operating minima

FILE

Simulator training

Operational demonstration

Approval

In-line operation Monitoring

Approval Process

Topics

• Aircraft Requirements

• Aerodrome Requirements

• Air Operator

• Approval Process

Aeroplane andAeroplane and

EquipmentEquipment

• Aircraft requires CAT II/III approval

• Operational approval is required

• JAR AWO section 1 (Autoland), Section 2 CAT II and section 3 (CAT III)

• FAA AC20-57A (autoland), AC 120-29 (CAT II) and AC 120-28D (CAT III)

Aeroplane and Equipment Certification

• Equipment listed in AFM to be operative

• MEL indicate status of CAT II/III

• Automatic landing certification requires simulations, assessments and flight test

• Touchdown, roll-out, automatic landing with various configurations and conditions tested

Aeroplane and Equipment Certification

• Successful approach– No system failure from 150m

– Speed maintained +/- 5 knots (no turbulence)

– Position of the aircraft between 90m and the DH - deviation of Glide path and Localizer do not exceed the values for excess deviation alerts

Aeroplane and Equipment Certification

Aerodrome Requirements

• Standards and Recommendations from ICAO Annex 10 (ILS) and ICAO Annex 14 (Aerodrome) are internationally accepted

• Additional requirements/variants may be found in national regulations

• Summary view of typical CAT II/III airfield

Aerodrome Requirements - Runway

• Runway length - operational requirement• Runway width - normally < 45m• Slope 1st/last quarter < 0.8%• Auto Landing - maximum 2% per 30m in area just before

threshold (60m by 200m)• Objects on runway strip - nil within 60m of centreline

(except frangible)• Taxi-holding positions not < 90m

Aerodrome Requirements Visual Aids -Aerodrome

• Markings centreline, touchdown, taxiway, taxi-holding position markings

• High intensity threshold, runway end lights, runway touchdown zone lights and runway centreline lights, taxiway centreline lights if <400m visibility, stop bars <400m visibility

Aerodrome Requirements Visual Aids - Approach

• Approach Lights required for CAT II only

• Extended centreline, side row, crossbar

Aerodrome RequirementsObstacle Clearance Area

• Obstacle Clearance Altitude/Height (OCH/OCA) - lowest height above threshold (aerodrome) used in establishing compliance with appropriate obstacle clearance criteria

• Minimum DH for CAT II cannot be less than established OCH/A

• OCH/A is a function of aircraft category

Aerodrome RequirementsObstacle Clearance Area

• Obstacle Free Zone– airspace above inner approach surface, inner

transitional and balked landing surfaces and that portion of the strip

– not penetrated by obstacles except frangible mounted required for air transportation purposes

Aerodrome RequirementsILS Facility

• Three categories (Annex 10)

– 60m (200ft) for CAT I

– 15m (50ft) for CAT II (acceptable to be used for CAT III with the highest minima (DH not< 50ft)

– Runway surface and along the runway for CAT III

Aerodrome RequirementsILS Facility

• ILS Critical Area - aircraft/vehicles are excluded during all ILS operations because they will cause disturbances to ILS signal

• ILS Sensitive Area - area extending beyond the critical area where movement and/or parking of aircraft and vehicles is controlled to prevent the possibility

• ILS beam to be protected by longitudinal separation

Aerodrome RequirementsRVR Measurements

• Number depend on type of operation• Generally 110 to 150m from centreline• Nominally 5m-10m in height

• ICAO recommends readout of 50m increments when RVR less than 800m and 25m increments when RVR less than 150m

• Normally ATC give Mid unless the others lower

Aerodrome RequirementsMaintenance

• % of unserviceable lights not to exceed 5%

• Recommended not adjacent lights

• Secondary power supply with switchover of maximum of 1 second

• ILS installations ground and flight checked

Aerodrome RequirementsATC

• Each Aerodrome to develop Low Visibility Procedures to include:– Procedures for ATC to be quickly informed of all

degradations of ILS performance– Procedures for ATC to be quickly informed of

any degradations in visual aids– Procedures for protection of OFZ by control of

ground traffic

Aerodrome RequirementsATC

• Each Aerodrome to develop Low Visibility Procedures to include:– Procedures for protection of ILS critical and

sensitive areas and between aircraft– Procedures for met services– Procedures for maintenance– Procedures for security

Air Operator Approval

• Aircraft type - AFM (Certification)• Aerodrome equipment - qualify• Aerodrome Operating Minima• Flight Crew Training• Flight Crew Procedures• Maintenance Program• Operational Demonstration

Air Operator Approval

• Operator take account of:– aircraft performance– composition of flight crew– runway which may be used– adequacy of visual and non-visual aids– aircraft navigation equipment– obstacle clearance height– availability of met reports

Air Operator Approval Minima

• Air Operator to ensure DH not lower than:– DH specified in the AFM– Minimum DH to which precision approach can

be used– The OCH for category of aircraft– The DH for which the flight crew is authorised– 100ft(30m)

Air Operator Approval CAT II DH

• An air operator to ensure that DH not lower than:– Minimum DH in the AFM

– Minimum DH to which the precision approach can be used

– The DH to which the crew is authorised

Air Operator Approval CAT III DH

– ICAO/JAA/FAA slight differences

– RVR Minimum related to DH

– Increase DH Increase RVR

– For RVR values less than 300m a go-around is assumed in event of auto-pilot failure

Air Operator Approval CAT II/III RVR

Air Operator ApprovalFlight Crew Procedures

• Satisfactory check of aircraft equipment• Effect on minima of failures - aircraft and ground• Procedures for approach, flare and roll-out• Procedures for failures/warnings• Minimum visual reference• Importance of correct seating eye position• Action to take if visibility deteriorates

Air Operator ApprovalFlight Crew Procedures

• Allocation of crew duties to permit PIC to devote himself to supervision/decision making

• Calls below 200ft - one pilot on instruments at all times

• Requirement for localizer area to be protected

• Use of information relating to wind, turbulence

• Procedures to use for practice approaches• Information on maximum deviation allowed

Air Operator ApprovalFlight Crew Procedures

• Flight preparation procedures

• Approach preparation procedures

• Approach Procedures

• Failures and associated actions– Continue– Revert to higher minimum– Go Around and reassess

Air Operator ApprovalFlight Crew Procedures

• Failures - Continue/Revert/Go Around– > 1000 Continue with higher DH if conditions met– < 1000 Go around and reassessment– Below AH go around required for autoland warning

• Abnormal Procedures– Provided in AFM– Simplified procedures found in FCOM

Air Operator ApprovalFlight Crew Training

• CAA requirements to be met– Ground training requirements

– Simulator Training requirements

– Initial, recurrent, conversion training/checking

– Type and command experience

• Airbus aircraft CAT II/III inherent functions

• Air operator required to seek approval from CAA

• Specific maintenance program

• Reliability program to be extended to monitor, track and control - > 95%

Air Operator ApprovalMaintenance

• Procedures to govern the capability of aircraft• Upgrading/downgrading procedure to be defined• Dispatch policy based on MEL• Dispatch criteria and status recorded in the

Technical Log • Requirements for tests to verify the CAT III

capability to be established

Air Operator ApprovalMaintenance

• To establish that the air operator can carry out CAT II/III with the appropriate success rate and level of safety

• Performance and reliability meet airworthiness certification

• Attention given to flight and maintenance procedures

Air Operator ApprovalOperational Demonstration

• Flight reports and/or recordings

• Recordings required for DH < 50ft

• Resulting approach/landing success rate

• Unsuccessful approaches due to ATC factors and/or ground facility difficulties may be excluded if proofs provided

Air Operator ApprovalOperational Demonstration

• Data Collection Crew Report:– airfield and runway used– weather conditions– time, adequacy of speed control– out of trim– capability of information (FD, AFCS, raw)– position through 100 ft and at touchdown– reason for failure if approach aborted

Air Operator ApprovalOperational Demonstration

• New Type:– 6 months at 200ft with procedures for lower

limits in place– Summary report to indicate to 90% confidence

level that 95% would be successful– No failure for 30 approaches– then 6 months at 50 ft with procedures for

lower limits in place

Air Operator ApprovalOperational Demonstration

• New Type:– then 6 months at 50 ft with procedures for

lower limits in place– summary report to indicate to 90% confidence

level that deviations are not worse than recorded during the certification programme

– typically 100 landings– sources of data distributed evenly

Air Operator ApprovalOperational Demonstration

• Continue to provide reports of service

• Number of approaches, by type where CAT II or III equipment was utilised to make satisfactory, actual or practice approaches to the applicable CAT II or III minima

• Unsatisfactory approaches by aircraft/airfield

• Detect any decrease in the level of safety

Air Operator ApprovalContinuos Monitoring

• Training purposes or data gathering

• CAT I beam - to be checked

• Terrain profile to be checked

• Generally accepted without activation of low visibility procedures

• Crew authorisation to be required

• Crew procedures established

• Vigilant for ILS disturbances

Air Operator ApprovalAutoland in > CAT I

Aircraft requirements Airfield requirements

CAT II/III cert ification CAT II/III facilities

Operator’s duties

Crew training

Flight Procedures

Maintenance programme

Airf ield operating minima

FILE

Simulator training

Operational demonstration

Approval

In-line operation Monitoring

Approval Process

Questions/Comments