GNSS. RNAV, PBN Course outline with guidelines

• The NAVSTAR Global Positioning System is a satellite navigation
system owned by the United States
• Comprising a constellation of satellites in medium Earth orbit, GPS
provides accurate positioning, velocity, and timing information
globally
• Consists of at least 24 satellites in various orbits to ensure continuous
coverage and redundancy
• Essential for en-route, terminal, and approach navigation,
contributing to precise navigation during all phases of flight

GLONASS
• GLONASS, or Global Navigation Satellite System, is the Russian counterpart
to GPS
• Similar to GPS, GLONASS provides global coverage, employing a
constellation of satellites in medium Earth orbit
• Offers redundancy and enhances navigation accuracy, especially in regions
where GPS signals may be compromised
• Integration of both GPS and GLONASS signals can improve navigation
accuracy and reliability for aviation applications
• Galileo is the European Union's satellite navigation system, designed to be
independent of other GNSS systems
• Aims to provide Europe with its own reliable and accurate positioning
information for various applications, including aviation

GLONASS
• Galileo offers a global constellation of satellites in medium Earth
orbit, enhancing navigation performance and ensuring availability

Beidou-2
• Beidou, also known as Compass, is China's satellite navigation system
• It consists of both regional and global components, providing
navigation services primarily in the Asia-Pacific region and expanding
globally
• The system enhances navigation accuracy, contributing to the overall
reliability of satellite navigation for aviation

2. World Geodetic System 1984
• The World Geodetic System 1984 is a global reference system used for
defining positions on the Earth's surface, including the coordinates
provided by GNSS
• WGS84 is the foundation for satellite navigation systems like GPS,
GLONASS, Galileo, and Beidou
• The system consists of a reference ellipsoid, a mathematical model
approximating the Earth's shape, and a geocentric coordinate system
• GNSS receivers use WGS84 coordinates to determine an aircraft's position,
altitude, and velocity accurately
• WGS84 coordinates include latitude, longitude, and altitude
• The WGS84 datum is regularly updated to account for the Earth's dynamic
nature

2. World Geodetic System 1984
• Crew members need to be aware of the importance of WGS84 in
coordinating navigation with various air traffic management systems
worldwide
• GNSS systems, when configured to WGS84, provide standardized and
interoperable navigation data, allowing for consistent and reliable air
traffic management across international airspace

3. Components of the GNSS
• Satellites and Orbits
• The Space Segment is the backbone of the Global Navigation Satellite System ,
consisting of a constellation of satellites meticulously placed in medium Earth
orbit
• Typically, GNSS systems like GPS maintain a constellation of at least 24
satellites, ensuring comprehensive global coverage and redundancy
• Orbits are carefully designed to optimize coverage, allowing multiple satellites
to be visible from any point on Earth at any given time, facilitating accurate
and continuous signal reception

Control Segment
• Master Control Station
• The Control Segment oversees the coordination, monitoring, and control of
the entire GNSS constellation
• The MCS manages satellite orbits, adjusts timing parameters, and monitors
overall system health, guaranteeing the reliability of signals transmitted to
users
• Monitoring Stations
• Ground-based Monitoring Stations are strategically located to track and
assess signals from GNSS satellites in real-time
• These stations collect crucial data related to satellite health, signal accuracy,
and system performance

Control Segment
• Data Uploading Stations
• Data Uploading Stations play a pivotal role in transmitting essential updates
and corrections to satellites
• The continuous communication between Data Uploading Stations and
satellites ensures that the GNSS constellation remains finely tuned and
capable of providing accurate navigation information

User Segment
• GNSS Receiver
• The User Segment involves the equipment onboard aircraft and other users
that receive and process GNSS signals for navigation purposes
• GNSS Receivers decode signals from multiple satellites to determine the
user's precise position, velocity, and time
• TSO-C129 / C
• Compliance with Technical Standard Order specifications, specifically C129 and C146, is
crucial for GNSS equipment
• Displays
• Displays are integral components that provide real-time information to the flight crew
based on data derived from the GNSS receiver
• These displays offer a comprehensive view of the aircraft's position, waypoints, routes,
and other pertinent navigation details, significantly enhancing situational awareness for
the crew

User Segment
• GNSS Antennas
• GNSS Antennas are responsible for receiving signals from satellites and are
instrumental in determining the accuracy of position fixes
• These antennas are designed to minimize interference and optimize signal
reception, playing a critical role in ensuring the overall performance and
reliability of the GNSS system

GPS Satellite Signals
• The GPS satellite signals operate in the L-band, a frequency band ranging
from 1 to 2 GHz
• Specifically, the GPS signals are transmitted in two frequency bands within
the L-band: L1 and L
• L1 frequency is centered around 1575.42 MHz, and it is used for civilian purposes
• L2 frequency is centered around 1227.60 MHz and is used for both military and
civilian purposes
• The L-band frequencies were chosen for satellite navigation due to their
ability to penetrate the Earth's atmosphere with relatively low signal
attenuation, making them suitable for reliable navigation signals
• The Almanac is a set of data transmitted by each GPS satellite that provides
information about the entire GPS constellation

GPS Satellite Signals
• It includes the approximate orbital parameters of all satellites in the
constellation, their health status, and information about other
satellites in the network
• The Almanac is essential for GPS receivers to acquire satellite signals
efficiently

Ephemeris Data
• Ephemeris data provides precise information about the orbits of
individual GPS satellites
• This data includes the satellite's position in orbit, velocity, and the
time of the satellite's clock
• Ephemeris data is crucial for accurate positioning calculations by GPS
receivers
• GPS receivers download ephemeris data from satellites to make real-
time calculations, ensuring accurate positioning information for
navigation

How the GPS Receiver Determines Position
• To determine a three-dimensional position , a GPS receiver needs signals
from a minimum of four satellites
• With signals from four satellites, the receiver can solve for its three-
dimensional position and the clock offset
• Three satellites are sufficient for a 2D position fix , but the fourth satellite is
necessary to account for the receiver's clock error
• The GPS receiver calculates the distance to each satellite by measuring the
time it takes for the satellite's signal to travel to the receiver
• The propagation time is determined by multiplying the signal travel time by
the speed of light
• By knowing the distance to at least four satellites, the receiver can
determine its position through trilateration

• Pseudorange is the apparent range between a GPS satellite and the
receiver, but it includes errors like clock errors and signal delays
• The GPS receiver calculates pseudoranges by measuring the time it takes
for the signal to travel from each satellite to the receiver and multiplying it
by the speed of light
• Trilateration is the mathematical technique used by the GPS receiver to
determine its position by intersecting spheres around each satellite
• Each satellite's signal provides a range or pseudorange, creating a sphere of
possible locations
• Ephemeris errors result from inaccuracies in the predicted satellite
positions transmitted by the satellites
• GPS receivers need accurate ephemeris data to calculate precise satellite
positions

• The ionosphere can delay GPS signals, causing errors in the calculated distance
• Dual-frequency GPS receivers can mitigate ionospheric errors by using the
difference in signal delay between the L1 and L2 frequencies
• Multipath occurs when GPS signals reflect off surfaces before reaching the
receiver, causing the receiver to calculate an incorrect distance
• Tall buildings, mountains, or other reflective surfaces can lead to multipath errors
• Antenna placement and signal processing techniques are used to minimize
multipath effects
• DOP is a measure of the geometric arrangement of satellites in the sky relative to
the receiver's location
• The four main types of DOP are Position DOP , Horizontal DOP , Vertical DOP , and
Time DOP

• Lower DOP values indicate better satellite geometry and result in
more accurate position fixes

• WAAS is a satellite-based augmentation system developed by the Federal
Aviation Administration in the United States
• It improves the accuracy, integrity, and availability of GPS signals over a
wide geographic area, including North America
• WAAS uses a network of ground-based reference stations to monitor GPS
satellite signals and correct errors, providing enhanced accuracy for
aviation applications
• EGNOS is the SBAS designed for Europe, providing augmentation to the
GPS signals over the European region
• Similar to WAAS, EGNOS uses ground reference stations to monitor and
correct GPS signals, enhancing navigation accuracy for aviation users in
Europe

• EGNOS improves the integrity and availability of GPS signals,
contributing to safer and more precise navigation
• RAIM is an ABAS feature that allows the GPS receiver onboard an
aircraft to autonomously monitor the integrity of the received
satellite signals

• It detects and alerts the pilot if there is a potential issue with the GPS
signals, such as a satellite malfunction or signal interference
• Fault Detection
• FD is a part of RAIM that identifies when there is a fault in one or more satellite signals,
potentially affecting the accuracy of the navigation solution
• Fault Detection and Exclusion
• FDE goes beyond FD by not only identifying faulty satellite signals but also excluding
them from the navigation solution, ensuring the accuracy and integrity of the position
calculation
• AAIM is an advanced version of RAIM that provides additional layers
of integrity monitoring and fault detection for aviation applications

• AAIM enhances the reliability of the GPS-based navigation solution by
continuously monitoring the integrity of the signals and taking
corrective actions in case of anomalies
• LAAS is a precision landing system that falls under the category of
GBAS
• It is designed to provide highly accurate and reliable navigation
guidance during the approach and landing phases of flight
• LAAS utilizes a network of ground-based reference stations to
augment GPS signals, allowing for precision approaches with vertical
guidance

3. Describe Required Navigational
Performance
• Definition
• Required Navigational Performance is a navigation specification that defines
the minimum level of accuracy and performance required for an aircraft to
operate within a specific airspace or along a defined route
• Key Principles
• Precision Navigation
• RNP specifies the accuracy, integrity, and performance criteria necessary for an aircraft
to navigate precisely within a designated airspace or along a specific route
• Risk Management
• RNP is designed to manage navigation risks by ensuring that aircraft operating in a
particular airspace can meet the required performance standards

Performance
• Components of RNP
• RNP Values
• RNP values are expressed in nautical miles and represent the lateral accuracy
requirements for the aircraft
• For example, an RNP 0.3 specification requires the aircraft to navigate within 0.3 NM of
the intended path for at least 95% of the total flight time
• Advanced Avionics
• Aircraft meeting RNP requirements are equipped with advanced avionics and navigation
systems, such as GPS or inertial navigation systems, capable of achieving the specified
performance levels

Performance
• Applications of RNP
• Terminal Operations
• RNP is often applied in terminal areas, allowing for precision navigation during approach
and departure procedures
• This is particularly beneficial in busy airports where accurate navigation is crucial for safe
and efficient operations
• En-Route Navigation
• RNP specifications are also used for en-route navigation, ensuring that aircraft can
maintain the required level of accuracy while traversing specific airways or waypoints

Performance
• Advantages of RNP
• Increased Precision
• RNP enhances navigation precision, allowing for more accurate and predictable aircraft
trajectories
• This precision is essential for managing airspace efficiently and minimizing conflicts between
air traffic
• Improved Safety
• By defining and adhering to specific performance standards, RNP contributes to enhanced
safety in air navigation
• The precise navigation allowed by RNP helps prevent navigation errors and reduces the risk of
mid-air collisions
• Flexibility in Procedures
• RNP specifications provide flexibility in designing and implementing navigation procedures,
contributing to optimized airspace utilization and efficient air traffic management

Performance
• Example: Consider an airspace where RNP 1 specifications are in place
• Overview of Navigation Inputs to an On-board RNAV System

Navigation Inputs
• Ground-Based Navigation Aids
• Traditional ground-based navigation aids, such as VOR and NDB , can provide
position information to the RNAV system
• While RNAV systems are designed for navigation without relying on ground-
based aids, they may use them as additional information sources, especially
in areas with limited satellite coverage
• Ground-Based Augmentation Systems
• GBAS, such as the Local Area Augmentation System , can provide highly
accurate and precise position corrections to the RNAV system during
approach and landing phases

Navigation Inputs
• Inertial Navigation Systems
• INS is an onboard navigation system that relies on accelerometers and
gyroscopes to continuously calculate the aircraft's position based on its initial
known position
• The RNAV system can use INS inputs to maintain accurate navigation
information, especially in situations where satellite signals may be
temporarily unavailable
• DME/DME Updating
• Distance Measuring Equipment paired with another DME or VOR/DME can
provide additional position updates to the RNAV system
• DME/DME updating helps enhance position accuracy by triangulating the
aircraft's position using multiple ground-based stations

Navigation Inputs
• Global Navigation Satellite Systems
• GNSS, such as GPS, is a primary space-based navigation input for RNAV
systems
• GPS provides highly accurate and continuous position updates to the RNAV
system, allowing for precise navigation in en-route, terminal, and approach
phases of flight
• Galileo, GLONASS, BeiDou
• Other GNSS constellations like Galileo , GLONASS , and BeiDou can also
contribute to RNAV when available
• Multi-constellation capability enhances system robustness, especially in areas
with potential signal obstructions or jamming

Integration of Inputs
• RNAV systems integrate inputs from these diverse sources to
determine the most accurate and reliable position information
• Advanced avionics and algorithms process the inputs in real-time,
ensuring seamless and continuous navigation, even in challenging
environments

• Example: Consider an aircraft equipped with an RNAV system flying
through a region with good GNSS coverage
• Position Calculation
• Function: Accurate and continuous calculation of the aircraft's position using available
navigation inputs
• Importance: Fundamental for RNAV systems to provide reliable navigation information
• Waypoint Sequencing
• Function: Sequencing and navigating to predefined waypoints or fixes along the flight
route
• Importance: Enables the aircraft to follow a predetermined route efficiently
• Navigation Mode Selection
• Function: Allows the crew to select different navigation modes, such as lateral navigation
, vertical navigation , or approach modes

• Importance: Facilitates flexibility in managing the aircraft's trajectory based on the phase of
flight
• Performance Monitoring
• Function: Monitoring and alerting the crew if the RNAV system deviates from specified
performance parameters
• Importance: Ensures the system operates within defined tolerances, enhancing safety
• Alerting System
• Function: Providing timely alerts to the flight crew in case of navigation anomalies or
deviations
• Importance: Supports situational awareness and prompt action in response to unexpected
events
• Multiconstellation GNSS Receiver
• Function: Capability to receive signals from multiple GNSS constellations

• Importance: Enhances system resilience and availability, especially in challenging signal
environments
• Barometric Vertical Navigation
• Function: Integration of barometric altitude for vertical navigation calculations
• Importance: Supports vertical navigation during approaches and altitude-sensitive procedures
• Terrain and Obstacle Database Integration
• Function: Incorporation of terrain and obstacle databases for terrain awareness and obstacle
clearance
• Importance: Enhances safety by providing visual and audible alerts for potential terrain
conflicts
• Updatable Navigation Database

• Function: Capability to update navigation databases with the latest information,
including waypoints, airways, and procedures
• Importance: Ensures the system uses current and accurate data for navigation
• Function: Ability to conduct RNAV/RNP instrument approaches, including procedures
with vertical guidance
• Importance: Supports precision approaches, enhancing accessibility to airports with
varied infrastructure
• Primary Navigation Display
• Type: Dedicated display presenting essential navigation information
• Importance: Centralized display for critical navigation data
• Flight Plan Display

• Type: Display of the programmed flight plan, including waypoints and route segments
• Importance: Enables the crew to review and modify the planned route
• Alerts and Warnings Display
• Type: Display for presenting alerts, warnings, and system status messages
• Importance: Ensures timely crew awareness of system status and potential issues
• Terrain and Obstacle Display
• Type: Display providing terrain and obstacle awareness
• Importance: Enhances situational awareness, especially during low-altitude operations
• Weather Information Display

• Type: Integration of weather data, such as radar or satellite imagery
• Importance: Supports weather-informed decision-making during flight
• Navigation Status and Performance Metrics Display
• Type: Display presenting real-time navigation status and performance metrics
• Importance: Assists the crew in monitoring the system's performance and adherence to
specified parameters

RNAV and RNP Navigation Specifications in
South Africa
• RNAV Specification: RNAV 10
• RNP Specification: RNP 10

Approach
• RNAV Specification: RNAV 0.3
• RNP Specification: RNP 0.3
• RNAV and RNP specifications in South Africa, as in many regions, are aligned with
the global standards set by ICAO
• The lateral accuracy values represent the distance within which the aircraft is
expected to stay for at least 95% of the flight time

Approach
• RNP specifications include on-board performance monitoring and
alerting, ensuring that the navigation system meets the required
performance standards
• Definition
• Advanced Required Navigation Performance is an advanced navigation
specification that defines specific performance standards for aircraft
navigation during critical flight phases
• A-RNP emphasizes a higher level of precision, flexibility, and sophistication
compared to standard RNP specifications

Approach
• Key Characteristics
• Enhanced Accuracy
• A-RNP requires a higher degree of accuracy in both lateral and vertical dimensions
• Flexibility in Procedures
• A-RNP provides operators and air traffic management with increased flexibility in
designing and implementing navigation procedures
• This flexibility is particularly advantageous for tailoring routes in congested airspace or
designing precise arrival and departure procedures
• Integration of Advanced Avionics
• Aircraft operating under A-RNP must be equipped with advanced avionics, including
sophisticated navigation systems capable of meeting the stringent performance
standards

Approach
• Key Characteristics
• These avionics systems often include multi-constellation GNSS receivers, advanced
inertial navigation systems, and on-board performance monitoring and alerting
capabilities
• Complex Terminal Procedures
• A-RNP is commonly applied in complex terminal areas, especially at busy
airports with multiple runways and high traffic volume
• Example: A-RNP may be utilized for precision approaches, allowing aircraft to
follow highly accurate paths during descent and landing

Approach
• Special Use Airspace
• A-RNP may be a requirement for operations in special use airspace, where
specific navigation precision is essential
• Example: Military operations or flights in restricted airspace may necessitate
A-RNP capabilities to ensure accurate navigation and compliance with
operational requirements
• Tailored Routes
• A-RNP allows for the creation of tailored routes based on the unique
capabilities of the aircraft and specific airspace requirements
• Example: Aircraft equipped with A-RNP capabilities can follow optimized and
customized routes, avoiding congested areas and minimizing fuel
consumption

Approach
• Aircraft Equipment
• To comply with A-RNP specifications, aircraft must be equipped with
advanced avionics that meet or exceed the performance requirements
• Example: Aircraft equipped with a state-of-the-art Flight Management System
capable of precise navigation and route optimization
• Operator Procedures
• Operators must establish and adhere to procedures that ensure compliance
with A-RNP specifications during flight planning, execution, and monitoring
• Example: Development and implementation of standard operating
procedures that consider A-RNP requirements in pre-flight planning and
during actual operations

Approach
• Regulatory Approval
• Regulatory authorities, such as the civil aviation authority of a country, grant
approval for A-RNP operations based on the certification of both the aircraft and the
operator's procedures
• Example: An airline may need regulatory approval to conduct A-RNP operations, and
this approval is contingent on meeting specific criteria outlined by the aviation
authority
• Increased Precision and Safety
• A-RNP delivers heightened navigation precision, enhancing safety and predictability
during critical phases of flight
• Example: During precision approaches in low-visibility conditions, A-RNP ensures that
aircraft can follow accurate glide paths, reducing the risk of runway incursions

Approach
• Optimized Airspace Utilization
• The flexibility provided by A-RNP allows for optimized airspace utilization,
supporting efficient traffic management and reducing congestion
• Example: A-RNP enables more direct routes, reducing fuel consumption and
contributing to overall airspace efficiency
• Tailored Operations
• A-RNP enables operators to tailor navigation procedures based on the unique
capabilities of their aircraft, promoting operational efficiency
• Example: Airlines can optimize routes based on specific aircraft performance
characteristics, leading to more fuel-efficient and environmentally friendly
operations

Note
• A-RNP is often introduced to accommodate the growing demand for
precision navigation in complex and congested airspace
• The specifics of A-RNP requirements may vary by region and
regulatory authority, and operators must ensure compliance with
applicable standards and procedures

Note
• Overview: Lateral Navigation is a component of GNSS-based approach
guidance that focuses on providing horizontal or lateral guidance to
the aircraft during approach and landing phases

Approach Minima
• Definition
• LNAV approach minima refer to the specified minimum criteria for lateral
navigation accuracy during a GNSS-based approach
• These criteria define the minimum lateral distance allowed between the
aircraft's actual position and the intended path or track
• Requirements
• LNAV approach minima are typically expressed in terms of lateral accuracy,
such as a certain number of nautical miles from the centerline or track
• For example, the approach minima for an LNAV approach might require the
aircraft to maintain a lateral accuracy within 0.3 nautical miles from the
intended track

Approach Minima
• Examples
• LNAV Approach with Lateral Deviation
• An LNAV approach might specify that the aircraft must remain within a defined lateral
corridor, such as ±0.3 nautical miles from the intended track
• If the aircraft deviates beyond this lateral corridor, it may no longer meet the approach
minima, and a missed approach or a transition to a higher level of precision may be
required
• Visual Criteria
• LNAV approach minima may also include visual criteria, such as visibility requirements
and cloud base heights, to ensure that the pilot maintains visual reference to the runway
environment
• LNAV is considered a non-precision approach, providing lateral
guidance without vertical guidance

Approach Minima
• While LNAV provides accurate lateral guidance, additional vertical
guidance may be provided by other systems or procedures, such as
Barometric Vertical Navigation or Localizer Performance with Vertical
Guidance

Approach Minima
• Example Scenario: Consider an aircraft conducting an LNAV approach
to a runway

Approach with Vertical Guidance
• Overview: An Approach with Vertical Guidance is a type of approach
that provides both lateral and vertical guidance to the aircraft during
the approach and landing phases
• Definition
• BARO VNAV approach minima refer to the specified minimum criteria for vertical
navigation accuracy during an approach where barometric altitude information is used
for vertical guidance
• These criteria define the minimum vertical distance allowed between the aircraft's actual
altitude and the intended glide path
• Requirements
• BARO VNAV approach minima are typically expressed in terms of vertical accuracy, such
as a certain number of feet from the glide path

• For example, the approach minima for a BARO VNAV approach might require the aircraft
to maintain a vertical accuracy within 50 feet from the intended glide path
• Effect of Temperature
• Temperature can impact barometric altimetry, and BARO VNAV systems account for
temperature effects to ensure accurate vertical guidance
• As temperature decreases, true altitude increases
• Examples
• Vertical Navigation with Temperature Compensation
• During a BARO VNAV approach, the aircraft's altimeter setting is adjusted to compensate for
temperature variations

• If the actual temperature is lower than the standard temperature, the altimeter setting is
increased, preventing the aircraft from descending below the intended glide path
• Definition
• LPV is an APV approach that provides both lateral and vertical guidance using satellite-
based augmentation systems , such as the Wide Area Augmentation System in the
United States
• Approach Minima
• LPV approach minima specify the minimum criteria for both lateral and vertical accuracy
during the approach
• These criteria define the allowable deviations in both horizontal and vertical dimensions

• Requirements
• LPV approach minima are typically more precise than non-SBAS approaches, providing a
high level of accuracy for both lateral and vertical navigation
• For example, the approach minima for an LPV approach might require the aircraft to
maintain a lateral accuracy within 0.1 nautical miles and a vertical accuracy within 50
feet
• Example Scenario
• LPV Approach with SBAS
• An LPV approach utilizes the precise vertical guidance provided by the SBAS, allowing the
aircraft to follow a three-dimensional path to the runway

• LPV approach minima are designed to ensure that the aircraft maintains a high level of
accuracy, allowing for safe and efficient landings in various weather conditions

Note
• APV approaches, particularly those using SBAS, provide a level of
accuracy and integrity close to that of ILS approaches
• LPV approaches are gaining popularity globally due to their accuracy
and accessibility in regions equipped with SBAS infrastructure

Note
• Overview: Lateral accuracy is a critical component of Performance-
Based Navigation , defining the precision with which an aircraft can
navigate laterally along its intended path
• Definition
• Total System Error represents the cumulative effect of errors within the navigation
system that contribute to lateral inaccuracies
• It includes errors arising from satellite geometry, signal integrity, atmospheric conditions,
and other factors that may impact the accuracy of the aircraft's lateral position
• Calculation
• TSE is typically expressed as a distance in nautical miles and represents the maximum
allowable lateral deviation between the aircraft's actual position and its intended track
• Calculation of TSE

Note
• Let's consider a PBN operation with a lateral accuracy requirement of 1 nautical mile
• If the TSE is specified as 0.5 nautical miles, it means that the overall system error,
considering all contributing factors, should not exceed 0.5 nautical miles
• Satellite Geometry
• The arrangement of satellites in the sky affects the quality of the navigation signals
received by the aircraft
• Signal Integrity
• Signal disruptions or interference, such as ionospheric disturbances or multipath
reflections, can introduce errors in the navigation signals and impact TSE
• Atmospheric Conditions

Note
• Changes in atmospheric conditions, such as ionospheric delays or changes in
temperature, can affect the accuracy of the GNSS signals and contribute to TSE
• Receiver Performance
• The quality and capability of the aircraft's GNSS receiver play a crucial role in
determining TSE
• Operational Approval
• PBN operations, including specific approach procedures or airspace requirements, are
subject to lateral accuracy criteria, often expressed through parameters like TSE
• Equipment and Procedure Compliance

Note
• Aircraft must be equipped with navigation systems and avionics that meet or exceed the
lateral accuracy requirements specified for the intended PBN operation
• Risk Mitigation
• Managing and mitigating TSE is crucial for ensuring the safety and efficiency of PBN
operations, especially during critical flight phases
• TSE is one of several parameters used to define the accuracy of PBN
operations

) Integrity
• Overview: Integrity in the context of Performance-Based Navigation refers
to the system's ability to provide timely warnings to the user when the
navigation solution falls below the required performance standards
• Definition
• Integrity is the measure of the trustworthiness of the navigation information provided by the
system
• It addresses the system's capability to detect and report errors, ensuring that the user is
aware when the navigation solution may be compromised
• Risk Mitigation
• Integrity plays a crucial role in mitigating the risk of using inaccurate navigation information,
especially during critical phases of flight
• Raim
• One example of an integrity monitoring system is RAIM, which is often employed in GNSS-
equipped aircraft

) Integrity
• Overview: Integrity in the context of Performance-Based Navigation refers
to the system's ability to provide timely warnings to the user when the
navigation solution falls below the required performance standards
• RAIM continuously monitors the navigation solution and detects anomalies
• Satellite Geometry
• Poor satellite geometry can increase the risk of integrity threats
• Redundancy
• Redundant sensors or multiple constellations can enhance integrity by providing alternative
sources of navigation information
• Fault Detection Algorithms
• Advanced fault detection algorithms within the navigation system contribute to the system's
ability to identify and mitigate integrity threats
• System Design

) Integrity
• Overview: Integrity in the context of Performance-Based Navigation
refers to the system's ability to provide timely warnings to the user
when the navigation solution falls below the required performance
standards
• The design of the navigation system, including the integration of integrity monitoring
features, is a key factor in ensuring the system's overall integrity
• Approach Procedures
• Integrity is crucial during precision approach procedures, where the aircraft relies on
accurate navigation information for safe descent and landing
• En-Route Operations
• In en-route operations, integrity ensures that the aircraft maintains accurate lateral and
vertical navigation along the intended route
• Safety-Critical Phases

) Integrity
• Overview: Integrity in the context of Performance-Based Navigation
refers to the system's ability to provide timely warnings to the user
when the navigation solution falls below the required performance
standards
• During safety-critical phases, such as takeoff and landing, integrity alerts are particularly
important to prevent hazardous situations

Continuity
• Overview: Continuity in PBN refers to the ability of the navigation system to
provide seamless and uninterrupted navigation information, especially
when transitioning between different navigation sources or phases of flight
• Definition
• Continuity ensures that the navigation system maintains a consistent and reliable flow of
information, preventing disruptions or gaps in navigation guidance
• Transitions
• It addresses the smooth transition between different navigation modes, sources, or
procedures
• Transition between GPS and Baro-VNAV
• During an RNAV approach, if an aircraft transitions from relying on GPS to using Barometric
Vertical Navigation due to loss of satellite signals, continuity ensures a seamless shift without
compromising accuracy
• Redundancy

Continuity
• Overview: Continuity in PBN refers to the ability of the navigation
system to provide seamless and uninterrupted navigation
information, especially when transitioning between different
navigation sources or phases of flight
• Redundant systems and multiple navigation sources contribute to continuity by providing
alternative information if one source becomes unavailable
• Smooth Transitions
• Well-designed transition procedures and algorithms ensure that changes in navigation
sources or modes occur smoothly, minimizing disruptions
• Dynamic Environment Adaptation
• The ability of the system to adapt to dynamic environmental conditions, such as changes
in satellite visibility, enhances continuity
• Approach and Departure Procedures

Continuity
• Overview: Continuity in PBN refers to the ability of the navigation
system to provide seamless and uninterrupted navigation
information, especially when transitioning between different
navigation sources or phases of flight
• Continuity is vital during approach and departure procedures, especially in situations
where the aircraft transitions between different navigation sources or phases
• Transition to Non-GPS Navigation
• In case of temporary loss of GPS signals, continuity ensures that the aircraft seamlessly
transitions to alternative navigation sources, such as inertial navigation or ground-based
aids

Availability of Systems
• Overview: Availability in PBN refers to the reliability and accessibility of the
navigation system, ensuring that it is operational and able to provide
navigation information when needed
• Definition
• Availability addresses the percentage of time the navigation system is operational and
capable of delivering accurate information
• Downtime
• It considers factors that may lead to system downtime, such as maintenance, system failures,
or environmental conditions
• Availability During Adverse Weather
• In adverse weather conditions, the availability of satellite signals may be affected
• System Reliability
• The reliability of the navigation system components, including sensors and receivers, directly
influences availability
• Maintenance Procedures

• Overview: Availability in PBN refers to the reliability and accessibility
of the navigation system, ensuring that it is operational and able to
provide navigation information when needed
• Effective maintenance procedures and regular system checks contribute to minimizing
downtime and ensuring high availability
• Redundancy and Backup Systems
• Redundant components and backup systems enhance availability by providing
alternatives in case of primary system failures
• Critical Phases of Flight
• Availability is particularly critical during safety-sensitive phases of flight, such as takeoff,
landing, and approach
• Operational Planning

• Overview: Availability in PBN refers to the reliability and accessibility
of the navigation system, ensuring that it is operational and able to
provide navigation information when needed
• Pilots and operators consider the availability of navigation systems when planning flights,
especially in regions or conditions where certain systems may be less reliable
• System Outages
• Availability considerations are essential for mitigating the impact of potential system
outages and ensuring that alternative navigation methods are available when needed

T-Bar - Initial Approach Fix Layout
• Overview: The T-Bar is a design concept used in aviation to depict the
arrangement of Initial Approach Fixes in the airspace
• Description
• The T-Bar consists of a primary feeder route leading to the initial approach fix and secondary
feeder routes forming a "T" shape with the primary route
• The primary feeder route represents the main entry point to the approach procedure, and
the secondary feeder routes form the crossbar of the "T."
• Usage
• Pilots use the T-Bar layout to identify the specific feeder route to follow when entering an
instrument approach procedure with multiple IAFs
• T-Bar in an Approach Chart
• Imagine an instrument approach chart depicting a T-Bar layout for an airport with two
runways and multiple IAFs
• Decision Point

T-Bar - Initial Approach Fix Layout
• Overview: The T-Bar is a design concept used in aviation to depict the
arrangement of Initial Approach Fixes in the airspace
• When approaching the T-Bar, pilots decide which feeder route to follow based on their
position, direction of arrival, and air traffic instructions
• Enhanced Situational Awareness
• The T-Bar layout enhances pilot situational awareness by providing a clear visual
representation of the available feeder routes and the primary entry point to the
approach procedure
• Flexible Entry Points
• The T-Bar allows for flexibility in choosing entry points based on factors such as wind
direction, traffic, or routing preferences, contributing to efficient and safe approach
operations

Y-Bar - Initial Approach Fix Layout
• Overview: Similar to the T-Bar, the Y-Bar is another design concept
used in aviation to illustrate the layout of Initial Approach Fixes on
instrument approach charts
• Description
• The Y-Bar consists of a primary feeder route leading to the initial approach fix and two
secondary feeder routes forming a "Y" shape with the primary route
• The primary feeder route represents the main entry point to the approach procedure,
and the secondary feeder routes form the arms of the "Y."
• Usage
• Pilots use the Y-Bar layout to identify and choose the appropriate feeder route for
entering an instrument approach procedure, especially when there are multiple IAFs
• Y-Bar in an Approach Chart
• Consider an instrument approach chart for an airport with multiple IAFs

• Decision Point
• As pilots approach the Y-Bar, they make a decision on which secondary feeder route to
follow based on their position, aircraft capabilities, and air traffic conditions
• Clear Entry Points
• The Y-Bar layout provides clear visual indications of the available entry points, aiding
pilots in making informed decisions on the appropriate feeder route to follow
• Enhanced Decision-Making
• The Y-Bar enhances decision-making by presenting a structured and easily interpretable
depiction of the IAF layout, contributing to safer and more efficient approach operations

• Both the T-Bar and Y-Bar layouts are tools used in approach chart design to
assist pilots in understanding the spatial arrangement of Initial Approach Fixes

Terminal Arrival Altitude - Reference Points
• Overview: The Terminal Arrival Altitude is a specified minimum
altitude at which an aircraft should arrive at a specific point within a
terminal area during an instrument approach
• Description
• Reference points within the TAA are typically prominent geographic features or
navigation fixes that serve as visual cues for pilots during the descent phase
• These points aid pilots in maintaining situational awareness and positioning the aircraft
correctly as they transition from en-route navigation to the terminal phase
• Usage
• Pilots use reference points within the TAA to cross-check their position, cross the
specified fixes at the prescribed altitudes, and align the aircraft with the final approach
course
• TAA with Reference Points

• Consider an instrument approach with a TAA that includes reference points such as
VORs, intersections, or geographic features
• Visual Cues
• Reference points may include visual cues on the ground or identifiable features on
navigation displays, enabling pilots to cross-check their position and make altitude
adjustments as needed
• Situational Awareness
• Reference points enhance situational awareness by providing visual cues that assist
pilots in confirming their position within the terminal area
• Vertical Profiling

• Pilots use reference points to execute a proper vertical profile during the descent,
ensuring that the aircraft reaches the appropriate altitudes at specific points within the
TAA

Terminal Arrival Altitude - Clearance Provided
• Overview: Clearance provided within the Terminal Arrival Altitude
specifies the altitudes at which an aircraft is cleared to descend while
transitioning from the en-route phase to the terminal phase of an
instrument approach
• Description
• Clearance provided within the TAA includes specific altitudes or altitude constraints
assigned to different segments of the approach procedure
• These clearances guide the descent of the aircraft and ensure it reaches the final
approach fix at the correct altitude for a stabilized approach
• Usage
• Pilots adhere to the clearance provided within the TAA to meet altitude constraints,
comply with procedural requirements, and maintain safe separation from other traffic
• ATC Clearance Instructions

instrument approach
• Air Traffic Control may provide clearance instructions such as "Descend and maintain
7,000 feet until established on the final approach course" within the TAA
• Pilots follow these instructions to descend to the specified altitude and establish the
aircraft on the final approach course in preparation for the approach
• Altitude Constraints
• Altitude constraints within the TAA may include crossing specific fixes at prescribed
altitudes, ensuring a step-down descent that aligns with the approach profile
• Compliance with Procedures

instrument approach
• Clearance provided within the TAA ensures compliance with established procedures,
helping pilots navigate the terminal phase safely and efficiently
• Collision Avoidance
• Altitude clearances within the TAA contribute to maintaining safe vertical separation
between arriving aircraft, reducing the risk of collisions
• Stabilized Approach
• Clearance instructions help pilots execute a stabilized approach by reaching key altitudes
at designated points within the TAA, facilitating a smooth transition to the final approach
segment

instrument approach
• TAA procedures are designed to facilitate the safe and orderly arrival of
aircraft into terminal airspace, and adherence to altitude clearances is crucial
for maintaining separation and ensuring a stabilized approach to the runway

RNAV Waypoint Types - Fly-By Waypoint
• Overview: RNAV waypoints are designated points in space used for
navigation by aircraft equipped with RNAV systems
• Definition
• A fly-by waypoint is a navigational point at which an aircraft begins a turn to the next leg
of its route before reaching the actual waypoint
• The aircraft's flight path passes to the side of the waypoint, and the turn initiation occurs
prior to reaching the waypoint itself
• Characteristics
• The aircraft's flight path is tangential to the waypoint, and the turn is initiated in advance
• This type of waypoint is often associated with a desired curved path through the airspace
• Fly-By Waypoint in a Procedure Turn
• Consider a procedure turn during an instrument approach
• RNAV SID or STAR Procedures

RNAV Waypoint Types - Fly-By Waypoint
• Overview: RNAV waypoints are designated points in space used for
navigation by aircraft equipped with RNAV systems
• In Standard Instrument Departures or Standard Terminal Arrival Routes , fly-by waypoints
are commonly used to define the lateral path and facilitate efficient turns
• Improved Path Predictability
• Fly-by waypoints contribute to a more predictable flight path, allowing for smoother
turns and precise lateral navigation
• Optimized Turn Management
• Aircraft equipped with RNAV systems can manage turns more effectively when
waypoints are designated as fly-by, enhancing operational efficiency

RNAV Waypoint Types - Fly-Over Waypoint
• Overview: Fly-over waypoints are another category of RNAV
waypoints, and their characteristics differ from fly-by waypoints
• Definition
• A fly-over waypoint is a navigational point that an aircraft passes directly over before
initiating a turn to the next leg of its route
• The aircraft's flight path intersects the waypoint, and the turn to the next leg occurs after
passing directly over the waypoint
• Characteristics
• The aircraft's flight path passes directly over the waypoint
• Turn initiation occurs after the aircraft has crossed over the waypoint
• Fly-Over Waypoint in Holding Procedures
• Imagine an aircraft in a holding pattern with a fly-over waypoint at the holding fix
• RNAV Arrival Procedures

• In RNAV arrival procedures, fly-over waypoints may be used to define specific points
where the aircraft follows a designated path before making turns to align with the final
approach course
• Precision in Turn Execution
• Fly-over waypoints provide precision in turn execution, allowing the aircraft to cross over
specific points before initiating turns to the next leg
• Alignment with Procedures
• Certain procedures, such as holding patterns or arrival routes, may be designed with fly-
over waypoints to achieve specific navigation and sequencing requirements

• The selection of fly-by or fly-over waypoints depends on the desired path
characteristics, procedure design, and specific operational considerations

Segment Minimum Altitudes in the Final
Approach Segment
• Overview: The Final Approach Segment of an instrument approach
procedure is a critical phase during which the aircraft aligns with the
runway for landing
• Definition
• Segment minimum altitudes are specified altitudes for different segments of the final
approach
• Shaded Boxes
• Shaded boxes on the approach chart represent specific segments where minimum altitudes
apply
• FAF Shaded Box
• The shaded box at the Final Approach Fix indicates the segment where the aircraft begins its
final descent to the runway
• Intermediate Shaded Boxes
• Intermediate shaded boxes may appear along the final approach course, each representing a
segment with its own minimum altitude
• ILS Approach with Shaded Boxes

Approach Segment
runway for landing
• Consider an ILS approach chart
• RNAV Approach
• In an RNAV approach, shaded boxes depict minimum altitudes for various segments
• Obstacle Clearance
• Segment minimum altitudes ensure obstacle clearance during the descent phase,
providing a safety buffer between the aircraft and potential obstacles
• Stabilized Approach
• Standardized segment minimum altitudes contribute to a stabilized approach, allowing
pilots to maintain a consistent descent profile for a safe landing
• Aircraft Separation

Approach Segment
runway for landing
• Minimum altitudes within shaded boxes contribute to vertical separation between
arriving aircraft, enhancing safety during the final approach phase
• Pilot Responsibility
• Pilots are responsible for adhering to segment minimum altitudes and ensuring that the
aircraft is at or above the specified altitude at each relevant point along the final
approach
• Air Traffic Control
• Air Traffic Control provides clearances and instructions to ensure that aircraft comply
with segment minimum altitudes, facilitating safe and orderly sequencing

Approach Segment
• Note: Segment minimum altitudes, as depicted in shaded boxes, are
crucial for maintaining safe and standardized descent profiles during
the final approach

Initial Fix
• Explanation: The Initial Fix is the point at which the aircraft intercepts
the final approach course
• Often named using the airport code or a relevant identifier
• "IA" or "IF" is commonly appended to indicate it as an initial fix
• Airport: Los Angeles International Airport
• LAXIA
• Identifier: XYZ
• XYZIF

Intermediate Fix
• Explanation: Intermediate fixes are waypoints along the final
approach course between the initial fix and the final approach fix
• A combination of the airport code or identifier, a numerical sequence, and
"IF."
• The numerical sequence indicates the order along the approach course
• Airport: Chicago O'Hare International Airport
• ORD01IF, ORD02IF, ORD03IF, .
• Identifier: ABC
• ABC01IF, ABC02IF, ABC03IF, .

Final Approach Fix
• Explanation: The Final Approach Fix is the point where the aircraft
transitions from the intermediate or en-route phase to the final
approach segment
• Similar to the initial fix but with "FAF" at the end
• Airport: San Francisco International Airport
• SFOFAF
• Identifier: DEF
• DEFFAF

Missed Approach Point
• Explanation: The Missed Approach Point is the point in space where,
if the required visual reference is not established, a missed approach
procedure is initiated
• Similar to the final approach fix but with "MAP" at the end
• Airport: Miami International Airport
• MIAMAP
• Identifier: GHI
• GHIMAP

Considerations
• Consistency Across Procedures
• Naming conventions should remain consistent across different approach
procedures at the same airport or within the same airspace
• Review Local Documentation
• Pilots and aviation personnel should review local Aeronautical Information
Publications or relevant documentation for any specific variations or
additional naming conventions used in a particular region

Considerations
• Review of Weather
• Objective: Understand the current and forecasted weather conditions
• Activities
• Analyze METAR and TAF reports
• Interpret weather charts and NOTAMs
• Discuss implications on the flight plan

Considerations
• Flight Planning
• Objective: Develop a comprehensive flight plan considering route, altitude,
and fuel requirements
• Activities
• Use flight planning tools
• Consider alternate airports
• Develop a fueling strategy

Aircraft Inspection
• Objective: Ensure the aircraft's airworthiness and readiness for flight
• Activities
• Conduct a pre-flight walk-around
• Inspect key components: control surfaces, tires, fluids, etc
• Review the aircraft logbook

Aircraft Inspection
• Safety Briefing
• Objective: Discuss safety procedures and emergency protocols
• Activities
• Review emergency checklists
• Discuss evacuation procedures
• Address specific safety considerations for the day

Aircraft Inspection
• CRM Discussion
• Objective: Emphasize effective communication and decision-making
• Activities
• Discuss roles and responsibilities in the cockpit
• Emphasize the importance of clear communication
• Review scenarios requiring effective CRM

Aircraft Inspection
• Preflight Briefing
• Objective: Review the flight plan and key considerations with the student
• Activities
• Go over the intended route
• Discuss key waypoints and potential challenges
• Review weather updates

Aircraft Inspection
• Aircraft Entry and Cockpit Setup
• Objective: Ensure a methodical and organized cockpit setup
• Activities
• Confirm documentation is onboard
• Set up avionics and navigation equipment
• Perform a cockpit check

Aircraft Inspection
• Start-up and Taxi
• Objective: Execute a safe engine start and taxi
• Activities
• Conduct pre-start checks
• Initiate engine start
• Taxi to the runway adhering to ATC instructions

Aircraft Inspection
• Takeoff and Initial Climb
• Objective: Safely and smoothly take off and climb to the initial cruising
altitude
• Activities
• Complete pre-takeoff checks
• Execute takeoff procedures
• Climb to the assigned altitude

Aircraft Inspection
• En-route Procedures
• Objective: Follow the planned route, monitoring navigation systems and
weather conditions
• Activities
• Navigate using avionics and charts
• Monitor weather updates
• Practice communication with ATC

Aircraft Inspection
• Approach and Landing
• Objective: Execute a stabilized approach and safe landing
• Activities
• Receive and follow ATC instructions
• Execute approach procedures
• Perform a safe landing

Aircraft Inspection
• Post-flight Review
• Objective: Evaluate the flight and discuss learning points
• Activities
• Review key aspects of the flight
• Discuss any deviations from the plan
• Address opportunities for improvement

Aircraft Inspection
• Documentation and Logbook
• Objective: Ensure proper documentation and logbook entries
• Activities
• Record any discrepancies or observations
• Complete post-flight paperwork
• Update logbook entries

1. Airmanship
• Precision Navigation: Execute precise navigation techniques using
GNSS/RNAV systems
• Situational Awareness: Maintain a clear understanding of the
aircraft's position, terrain, and airspace
• Adherence to Procedures: Strictly follow published procedures and
adhere to assigned altitudes and courses

Example Scenario
• Prioritize precise navigation during an RNAV approach by cross-
referencing waypoints and aircraft position on the moving map
display

Safety Measures
• Terrain Awareness: Constantly monitor terrain clearance using Terrain
Awareness and Warning System during the approach
• Collision Avoidance: Use Traffic Collision Avoidance System to
maintain separation from other aircraft
• Weather Monitoring: Continuously assess weather conditions, and be
prepared to execute a missed approach if weather parameters are not
met

Example Scenario
• While conducting a GNSS approach, if the weather deteriorates below
minimums or there's conflicting traffic, prioritize safety by
immediately executing the missed approach procedure

Understanding System Limitations
• Satellite Availability: Acknowledge potential satellite signal
interruptions and the impact on navigation accuracy
• Database Currency: Ensure that navigation databases are current and
not expired to avoid reliance on outdated information
• Equipment Functionality: Be aware of any limitations in the aircraft's
GNSS/RNAV equipment

Example Scenario
• If the GNSS signal is temporarily lost, pilots should revert to alternate
navigation methods or follow the published missed approach
procedure

Effective Communication
• Crew Briefing: Conduct a thorough pre-flight briefing, emphasizing
roles and responsibilities during the approach
• Clear Communication: Use concise and clear communication with the
crew and air traffic control throughout the approach
• Prior to the approach, conduct a CRM briefing discussing the
approach procedure, expected altitudes, and potential contingencies,
ensuring both pilots are aware of the plan

Pre-flight Planning
• Airmanship: Thoroughly review the RNAV approach procedure and
associated NOTAMs
• Safety: Check weather forecasts, ensure equipment functionality, and
discuss potential threats during the CRM briefing
• Limitations: Verify the currency of navigation databases and assess
satellite availability

Pre-flight Planning
• Initial Approach and Descent
• Airmanship: Begin the descent from the appropriate IAF, following the published
RNAV path
• Safety: Monitor terrain clearance using TAWS and maintain a stabilized descent
profile
• CRM: Communicate altitude changes, cross-check waypoints, and ensure both pilots
are actively engaged
• Intermediate Approach Phase
• Airmanship: Execute turns and altitude changes precisely, adhering to RNAV lateral
and vertical profiles
• Safety: Continuously monitor for traffic using TCAS and maintain awareness of the
surrounding airspace
• Limitations: Be prepared for any loss of GNSS signal and have alternate navigation
methods in mind

Final Approach
• Airmanship: Execute a stabilized final approach, maintaining proper
airspeed and descent rate
• Safety: Continuously monitor for obstacles and other traffic
• CRM: Communicate any deviations from the plan promptly and be
ready to initiate a missed approach if necessary

Final Approach
• Missed Approach
• Airmanship: Execute the missed approach procedure precisely, climbing to
the specified altitude
• Safety: Avoid obstacles, maintain positive aircraft control, and communicate
intentions to ATC
• CRM: Confirm with the other pilot that the missed approach procedure is
being executed, and communicate any changes to ATC

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