VALIDATION & IMPLEMENTATION CONSIDERATIONS Lead Instructor: Walter.White@AirTraffic.Biz
OBJECTIVE This module provides an overview of airspace concept and flight procedure validation and considers aspects of PBN implementation.
Why do validation? • Validate Airspace Concept and resultingroutes/instrument flight procedures • Assess if ATM objectives are achieved • Confirm flyability of Instrument Flight Procedures • Identify possible problems and develop mitigations • Provide evidence design is safe Validation is an ongoing process
CAUTION GARBAGE IN RUBBISH OUT!!!
Validation methods Airspace Concept • Chalk and talk • Modelling • FTS • RTS Flight Procedures • PC based simulation • Flight simulators • Ground checks • FMS simulator • Live trials
Airspace Concept Validation • General Considerations • Aircraft performance • Sterile environment?/Secondary traffic • Special events
Advantages of Modeling • Flexible • Simple • ‘What if’ investigations • Easy to test large number of traffic samples • Data derived from real traffic and ATC environment
Modeling - Limitations • Crude • Only high level data • Basic aircraft performance • Does not replicate controller interventions • Simplified • Subjective
Fast Time Simulation (FTS) • Used for sector capacity • Quality data • Flexible • Good acceptance of results • Evaluate TLS • Used for Safety Case
FTS - Limitations • Simplified model • Only statistical data • No active controller interaction during FTS • Accuracy of models is key • Aircraft performance • Met conditions
Real Time Simulation (RTS) • Best method to simulate ATC trials • High quality data • Feed controllers/ pseudo pilots • Human factor • Can be part of Safety Case • No risk to live ops • Unlimited scope
RTS - Limitations • Limited scope • Designed for training ATC • Aircraft performance not representative • Not designed for post simulation evaluation needed for Airspace concept evaluation
Flight Simulator • High quality data • Confirm design aspects • Fly-ability • Efficiency • Met impact • Possible link to RTS
Flight Simulator - Limitations • Manual data collection • For range of aircraft types/meteo conditions time consuming and expensive • Pilots needed to fly the simulator
Live ATC Trials • Most accurate • Real data • Feedback from all users
Live ATC Trials - Limitations • Safety mitigations required • High detail required – large effort for a concept evaluation • Limited scope • Limited flexibility
Procedure Validation • Ground Validation • Obstacle clearance • Charting • Coding • Flyability
Procedure Validation • Flight Validation • Data verification • Obstacle verification (optional) • Flyability (workload, charting, manoeuvring) • Infrastructure • Database Validation
Ground Validation • Obstacle clearance • Independent review by procedure designer • Charting • Independent review • Coding • Software tool • Expert review • Flyability – software tools (from PC-based to full flight simulator) • Not necessarily an issue with standard procedures (e.g. ‘T’ approaches), but critical for some aircraft types • Range of aircraft and meteo conditions Independent review – can be part of same organisation
Flyability • Independent assessment • Use of validation tools • Use of aircraft simulators • more than one type • Flight checks • Initial operational checks
Validation Tools /2 B737-300 ISA -20 Wind 250/25 B737-300 ISA +40 Wind 320/20
Different Aircraft & Different Conditions CA 500ft AGL; DF LL001; TF FARKS; TF… No wind designed path A319 B737/400 B747/400 A340/300 A320/319
Wind Effect CA 500ft AGL; DF LL001; TF FARKS; TF… Wind from 045° A319 B737/400 B747/400 A340/300 A320/319
Mitigation by Speed Restriction CA 500ft AGL; DF LL001; TF FARKS [210kts]; TF… Wind from 045° A319 B737/400 B747/400 A340/300 A320/319
Leg Length - Too Short CA 2000ft AGL; DF BRW02 No wind ATR42 B 747-400 A340-300 2.7NM
Leg Length - Acceptable CA 2000ft AGL; DF BRW02 No wind ATR42 B 747-400 A340-300 4.6NM
Flight Procedure Validation • Obstacle verification • Has full obstacle survey been completed • TAWS / GPWS alerts • Flyability • Detailed workload and charting assessments • High level qualitative assessment of manoeuvring via accurate flight simulator. • Infrastructure assessment • Runway markings, lighting, communications, navigation, etc
Flight Inspection • Flight Inspection often confused with Validation • Flight Inspection Addresses: • Navaidperformance and receptionfor DME/DME • Unintentional interference for GNSS • Flight Validation may not fully address Navaid Infrastructure issues (example: inspect DME/DME reception)
RNAV Procedure Description • Procedures are currently published as charts and as textual descriptions. • The charts are used by the pilots and ATC. • Database providers require clear, and unambiguous procedure descriptions and use the charts to validate/check.
RNAV Procedure Description • RNAV procedures defined by: • Sequence of waypoints • Identifier • Co-ordinates • Fly-over/fly-by/fixed radius • Path Terminators - ARINC 424 • Altitude restrictions • Speed restrictions • Direction of turn • Required navaid
Charting PT118 PT119 PT121 PT120 203° RW20 5000 Waypoint sequence 4000 113° 169° ARZ 29.3NM 236° ALM 27.4NM FAF Fly-over/fly-by/fixed radius 293° 4000 Speed/Altitude Restrictions 4500 Leg distance & magnetic track Fix information Turn direction MAPt 350° PT125
Procedure Description for Database Providers preferred by data houses • Textual description is usually used to provide formal statement of procedure. • Often open to interpretation. • RNAV procedures require more specific details including path terminators. • Can result in lengthy descriptions. • Alternative descriptive methods have been adopted by OCP: • Tabular layout • Formalised textual description • Formalised short-hand description
Waypoint Identification • IFPP introduced concept of strategic and tactical waypoints • Strategic waypoints: • identified by co-located navaid or by unique five-letter pronounceable “name-code” (5LNC). • 5LNCs may be misinterpreted when issuing “direct” or vector instructions (ALECS, ALEKS, ALYKS). • Tactical Waypoints may be used in a specific terminal area for vectoring, identification, and sequencing. • Tactical waypoint naming is specific to area.
Strategic Waypoint • A waypoint in the terminal area which is: • Of such significance to the ATS provider that it must be easily remembered and stand out on any display, or • Used as an ‘activation point’ to generate a message between computer systems when an aircraft passes it. • Strategic waypoints are identified with 5LNCs unless they are co-located with a navaid, when the 3 letter navaid ID is used.
Tactical Waypoint • Tactical: a waypoint which is defined solely for use in the specific terminal area and has not been designated a strategic waypoint. • Identified as AAXNN, where: • AA - the last two characters of the aerodrome location indicator; • X - a numeric code from 3to 9 (N, E, W and S may be used instead if a State has a requirement for quadrantal information) • NN - a numeric code from 00 to 99.
RNAV Procedure IdentificationNaming Conventions • “RNAV(GNSS) RWY 23” - is RNP approach • “RNAV(RNP) RWY 23” - is RNP-AR approach *ICAO State Letter SP 65/4-13/24, proposed change 1 DEC 2022 to: RNP and RNP(AR)
Charting Altitude Restrictions • An altitude window : FL220 • 10,000 • A “hard” altitude : 3000 • An “at or below” altitude : 5000 • An “at or above” altitude: 7000
FMS/RNAV limitations • Airspace Designers often want STARS to a metering fix and additional STARs to join to initial approach Fix for each runway • Cannot have two STARs in same flight plan in FMS • Airway and approach transitions needed
Implementation/1 • Implementation decision • PRE IMPLEMENTATION REVIEW!!!! • ATC system consideration • TRAINING • AIRAC cycle
Implementation/2 • Monitor process • Support OPS • Redundancy or contingency procedures • Support controllers and pilots • Maintain log • Post Implementation Safety Assessment
Post Implementation • Safety Assessment • Have objectives been met • Have any safety issues been identified • What improvements could be made • Is there a continuing quality process