Approach Plate Symbology: A US Pilot’s Guide

Approach plates, standardized by the FAA, constitute a crucial resource for pilots navigating instrument approaches. This guide focuses on approach plate symbology, the standardized graphical language essential for interpreting these charts. Jeppesen charts, an alternative to government-produced charts, also employ unique symbology conventions with similar intent. Proficiency in decoding approach plate symbology directly impacts a pilot’s ability to safely execute instrument procedures, particularly in challenging environments like those frequently encountered at Denver International Airport (DIA). Mastery of approach plate symbology is a critical component of crew resource management (CRM), ensuring shared understanding and effective communication during flight operations.

Navigating with Precision: Understanding Instrument Approach Plates

Instrument approach plates are the cornerstone of safe and efficient flight operations under Instrument Flight Rules (IFR). They are detailed charts designed to guide pilots during the approach and landing phases of a flight when visual references are limited or nonexistent.

These plates provide a structured and standardized method for transitioning from en route flight to a safe landing, particularly in adverse weather conditions. Understanding their intricacies is paramount for any pilot operating in the IFR environment.

Defining Instrument Approach Plates

An instrument approach plate is essentially a graphical and textual representation of a specific instrument approach procedure. It outlines the course to be flown, altitudes to be maintained, and distances to be traversed, all predicated on established navigational aids and predetermined criteria.

The plate incorporates information from various sources, including ground-based navigational aids (such as VORs and ILS), satellite-based systems (GNSS), and obstacle clearance data.

This integrated approach ensures a reliable and predictable path to the runway.

The Indispensable Role in IFR Flight

In the realm of IFR flight, where pilots rely solely on instruments for navigation and control, approach plates are absolutely essential. They provide the sole source of guidance during critical phases of flight, allowing for controlled descents and precise alignment with the runway.

Without instrument approach plates, safe landings in low-visibility conditions would be virtually impossible.

Moreover, these plates are not merely aids; they are legally mandated documents that pilots must possess and understand to operate under IFR.

The Guardians of the Skies: Regulatory and Charting Bodies

The integrity and accuracy of instrument approach plates are maintained through the diligent efforts of regulatory and charting bodies. Organizations such as the FAA (Federal Aviation Administration) in the United States, and similar aviation authorities worldwide, set the standards and oversee the creation and maintenance of these crucial documents.

Charting organizations, such as NACO (National Aeronautical Charting Office) also play a critical role in surveying, compiling, and publishing the data that forms the foundation of each approach plate. These bodies, working in concert, ensure that pilots have access to reliable and up-to-date information.

Regulatory and Charting Bodies: The Architects of Approach Plates

Navigating the complexities of instrument flight requires a foundation of trust in the information presented. The reliability of instrument approach plates hinges on the rigorous processes and unwavering commitment of the organizations responsible for their creation, maintenance, and regulation. Understanding the roles of these entities is paramount to appreciating the precision and standardization inherent in these critical navigational tools.

The FAA’s Oversight Role

The Federal Aviation Administration (FAA) stands as the primary governing body for aviation within the United States. Its mandate encompasses far more than just air traffic control; it also includes the crucial task of establishing and enforcing standards for air navigation products.

The FAA sets the criteria for instrument procedures, ensuring that they adhere to stringent safety requirements. This oversight extends to the design and publication of approach plates, guaranteeing a consistent and reliable experience for pilots nationwide.

The FAA’s influence is not limited to creating new procedures; it also oversees the ongoing maintenance and amendment of existing ones. This involves continuous monitoring of airspace, obstacle surveys, and other factors that may necessitate changes to approach plates.

NACO/NGS: Charting the Course

Within the FAA structure, the National Aeronautical Charting Office (NACO), in conjunction with the National Geodetic Survey (NGS), plays a vital role in the actual production of charts. NACO is directly responsible for collecting, processing, and disseminating aeronautical information, transforming raw data into usable charts for pilots.

NGS, a component of the National Oceanic and Atmospheric Administration (NOAA), provides the geodetic foundation upon which these charts are built. Their work ensures the accurate positioning of airports, navigational aids, and other critical features.

The collaboration between NACO and NGS ensures the accuracy and reliability of the geographic data presented on approach plates. This includes everything from airport layouts to obstacle heights. This partnership is essential for maintaining safe separation from terrain and other hazards during instrument flight.

Jeppesen: A Commercial Partner in Safety

Jeppesen, a Boeing company, stands as a prominent commercial provider of flight information services, including instrument approach charts. While not a regulatory body, Jeppesen plays a significant role in the dissemination and accessibility of approach plates worldwide.

Jeppesen meticulously adheres to FAA and ICAO standards in the creation of its charts. This ensures consistency and compatibility with government-produced resources.

Furthermore, Jeppesen often enhances its charts with additional features designed to improve situational awareness. This commitment to quality and usability has made Jeppesen a trusted resource for pilots globally.

ICAO’s Global Influence

The International Civil Aviation Organization (ICAO), a specialized agency of the United Nations, sets the global standards for aviation. While the FAA governs US airspace, ICAO’s influence extends worldwide, promoting harmonization and interoperability across national borders.

ICAO establishes the fundamental principles for instrument approach procedures, ensuring a consistent level of safety and predictability across different countries. These standards address everything from obstacle clearance criteria to charting symbology.

The adoption of ICAO standards facilitates international air travel and enhances safety by promoting a common understanding of instrument flight procedures. This global harmonization is critical in an interconnected world.

Core IFR Concepts: Building Blocks for Understanding Approach Plates

Navigating the world of instrument approach plates demands a solid grasp of underlying IFR (Instrument Flight Rules) principles. These concepts form the bedrock upon which the interpretation and execution of instrument approaches are built.

Without this foundation, the complexities of approach plates can become overwhelming. This section dissects those core elements, providing the necessary knowledge to confidently and safely navigate IFR conditions.

Essential IFR Terminology and Their Implications

IFR (Instrument Flight Rules)

Instrument Flight Rules (IFR) govern flight operations when visual references are limited or absent. Approach plates are indispensable under IFR, providing the necessary guidance to safely descend and land at an airport. They are designed to ensure obstacle clearance and maintain standardized procedures in low visibility conditions.

Altitude and Obstacle Clearance: MSA, MEA, MOCA, MAA

MSA (Minimum Safe Altitude)

The Minimum Safe Altitude (MSA) provides a minimum altitude within a specified radius of a navigation facility or airport, ensuring obstacle clearance of 1,000 feet above the highest obstacle within that area. It is important to note that MSA is for emergency use and may not provide radio navigation signal coverage.

MEA (Minimum Enroute altitude)

The Minimum Enroute Altitude (MEA) is the lowest published altitude between radio fixes which assures acceptable navigational signal coverage and meets obstacle clearance requirements between those fixes. MEA ensures reliable navigation signal reception and obstacle clearance along a specific route.

MOCA (Minimum Obstruction Clearance Altitude)

The Minimum Obstruction Clearance Altitude (MOCA) is the lowest published altitude in effect between radio fixes on VOR airways, off-airway routes, or route segments, which meets obstacle clearance requirements for the entire route segment. MOCA only assures acceptable navigational signal coverage within 22 nautical miles of a VOR.

MAA (Maximum Authorized Altitude)

The Maximum Authorized Altitude (MAA) is the highest altitude on a Federal airway, jet route, VOR airway, or other direct route for which an MEA is designated. MAA is established to prevent signal interference between navigation facilities operating on the same frequency.

Vertical Transition Points: Transition Altitude/Level

The transition altitude is the altitude at or below which the altimeter is set to the local QNH (local atmospheric pressure reduced to sea level). The transition level is the lowest flight level available for use above the transition altitude. These concepts are designed to standardize altitude references during ascent and descent.

Approach Procedure Components

Procedure Turn: Reversal Maneuver

A procedure turn is a maneuver prescribed when it is necessary to reverse direction to establish an aircraft on the intermediate approach segment or final approach course. It allows for course alignment when a direct approach is not feasible.

Holding Pattern: Controlled Delay

A holding pattern is a predetermined maneuver which keeps an aircraft within a specified airspace while awaiting further clearance from air traffic control. Holding patterns are used to manage air traffic flow and allow for spacing between aircraft.

Key Fixes: FAF and MAP

Final Approach Fix (FAF)

The Final Approach Fix (FAF) is the point on an instrument approach procedure where the final approach segment begins. This is where the aircraft transitions from the intermediate segment to the final descent toward the runway.

Missed Approach Point (MAP)

The Missed Approach Point (MAP) is the point in an instrument approach procedure at or after which the prescribed missed approach procedure must be executed if the required visual reference has not been established. It’s the point of no return, dictating a climb to a safe altitude and further instructions from ATC.

Vertical Guidance Benchmarks: DA/DH and MDA

Decision Altitude (DA) / Decision Height (DH)

Decision Altitude (DA) or Decision Height (DH) is a specified altitude or height in a precision approach at which a missed approach must be initiated if the required visual reference to continue the approach has not been established. DA is referenced to mean sea level (MSL), while DH is referenced to the threshold elevation.

Minimum Descent Altitude (MDA)

The Minimum Descent Altitude (MDA) is the lowest altitude, expressed in feet above mean sea level, to which descent is authorized on final approach or during circle-to-land maneuvering in execution of a non-precision approach. If visual reference is not established at MDA, a missed approach must be executed.

Visual Aids: VDP

The Visual Descent Point (VDP) is a defined point on the final approach course of a non-precision straight-in approach procedure from which normal descent from the MDA to the runway touchdown point may be commenced provided the approach threshold of that runway, or approach lights are clearly visible to the pilot.

Stepdown Fixes

Stepdown fixes permit descent to a lower MDA during an instrument approach. These fixes must be positively identified using specified navigation aids.

Circling Approach: Maneuvering for Alignment

A circling approach is a maneuvering procedure used when a straight-in approach is not possible or desired. This involves visually maneuvering the aircraft around the airport to align with a different runway for landing.

RNAV and GPS Based Approaches

RNAV (Area Navigation)

RNAV, or Area Navigation, allows an aircraft to follow a desired flight path without needing to fly directly over ground-based navigation aids. RNAV utilizes GPS or other navigation systems to determine aircraft position.

LNAV (Lateral Navigation)

LNAV (Lateral Navigation) refers to a non-precision approach utilizing RNAV guidance. It provides lateral guidance to the runway, but lacks vertical guidance.

ILS (Instrument Landing System) Components

Localizer: Lateral Guidance

The localizer is a component of the ILS (Instrument Landing System) that provides lateral guidance to the runway centerline. It transmits signals that allow the aircraft to align with the runway.

Glide Slope/Glide Path: Vertical Guidance

The glide slope (ILS) or glide path (for other precision approaches like LPV) provides vertical guidance during the final approach segment. It helps the pilot maintain the correct descent angle to the runway.

Threshold Crossing Height (TCH)

The Threshold Crossing Height (TCH) is the height above the runway threshold at which the glide slope or glide path should intercept the runway. It’s a reference point for maintaining the correct vertical profile.

Airport and Runway References

Touchdown Zone Elevation (TDZE)

The Touchdown Zone Elevation (TDZE) is the elevation of the highest point in the touchdown zone and is published on instrument approach charts, providing a reference for altitude calculations.

Airport Elevation

Airport elevation is the highest point of an airport’s usable runway surface measured in feet above mean sea level. It is a fundamental reference point for all altitude calculations.

Approach Lighting System (ALS)

The Approach Lighting System (ALS) is a configuration of lights that extends outward from the runway threshold, providing visual cues to pilots during low visibility conditions. ALS assists in transitioning from instrument to visual flight.

Supplementary Information

Aviation Chart Supplements (Chart Supplements US)

Aviation Chart Supplements (formerly Airport/Facility Directory) provides comprehensive information about airports, including services, runways, lighting, and navigational aids. It complements approach plates with detailed airport-specific data.

Flight Planning Software (ForeFlight, Garmin Pilot)

Flight planning software like ForeFlight and Garmin Pilot streamline the process of accessing, viewing, and interpreting approach plates. These tools offer features like geo-referencing, real-time weather overlays, and interactive route planning.

Decoding the Approach Plate: A Section-by-Section Guide

Instrument approach plates are dense documents, brimming with information crucial for the safe execution of IFR procedures. Mastery lies not only in understanding individual elements, but in synthesizing them into a cohesive mental picture of the intended flight path. This section dissects the approach plate, providing a structured guide to its key components and their interpretation.

Plan View: The Bird’s-Eye Perspective

The plan view offers a top-down depiction of the approach, revealing critical navigational elements. It is essential for understanding the lateral aspects of the procedure.

• Course Information: Note the inbound and outbound courses, depicted with arrows indicating the direction of flight. Pay careful attention to whether these are magnetic courses or true courses, and adjust accordingly.

• Navigational Aids: Identify the location of VORs, NDBs, and GPS waypoints, and their associated frequencies. This is paramount for verifying correct identification and tracking of these aids.

• Airspace Boundaries: Be aware of depicted airspace boundaries, special use airspace (SUA), and any relevant restrictions. Failure to comply with these restrictions can lead to serious consequences.

• Minimum Sector Altitudes (MSA): MSAs provide obstacle clearance within a specified radius of a navigation facility. These altitudes provide 1000 feet of obstacle clearance, but do not guarantee signal coverage.

• Holding Patterns: Understand the entry procedures, inbound/outbound courses, and timing associated with any depicted holding patterns. Accurate execution of holding procedures is crucial for traffic management.

Profile View: Vertical Guidance and Obstacle Clearance

The profile view provides a side-on representation of the approach, focusing on altitude restrictions and descent angles. It’s critical for maintaining proper vertical separation.

• Glide Slope/Glide Path: For precision approaches like ILS, the glide slope (or glide path for RNAV approaches) angle and intercept altitude are clearly indicated. Adherence to the glide slope ensures both vertical guidance and obstacle clearance.

• Stepdown Fixes: Non-precision approaches often utilize stepdown fixes to allow for lower descent angles. Ensure you are established at each fix before descending to the next lower altitude.

• Minimum Descent Altitude (MDA): In non-precision approaches, the MDA is the lowest altitude to which descent is authorized until the visual references are acquired. Descent below MDA without visual contact with the runway environment is strictly prohibited.

• Decision Altitude (DA) / Decision Height (DH): For precision approaches, DA/DH is the altitude at which a missed approach must be initiated if the required visual references are not established.

• Obstacle Depiction: Pay close attention to any obstacles depicted on the profile view, especially those near the final approach course. This ensures terrain awareness.

Minimums Section: Determining Approach Feasibility

This section specifies the visibility and altitude requirements for each approach type, categorized by aircraft approach category. Understanding these minimums is vital for determining whether an approach is legally and safely possible.

• Approach Category: Determine the appropriate approach category based on your aircraft’s approach speed (Vat). Note that incorrectly using an approach category can lead to unsafe maneuvering and reduced obstacle clearance.

• Decision Altitude (DA) / Decision Height (DH): If DA/DH is unavailable, then the approach is not legal.

• Minimum Descent Altitude (MDA): Carefully note the MDA for each approach type. The MDA is the lowest altitude to descend to without runway environment recognition, when the pilot must either land or execute a missed approach.

• Visibility Requirements: Pay close attention to the visibility requirements specified for each approach. This is either stated in Statute Miles (SM) or Runway Visual Range (RVR).

Notes Section: Essential Supplemental Information

This section contains critical textual information that supplements the graphical depiction on the approach plate. Ignoring the notes section can lead to misunderstandings and potentially dangerous situations.

• Radio Frequency Changes: Any changes in radio frequencies during the approach are noted here.

• Inoperative Components: Information regarding inoperative components of the navigation facility or approach lighting system are listed here. This may affect the approach’s minimums and usability.

• ATC Instructions: Specific ATC instructions or procedures unique to the approach are often detailed in the notes section.

• Timing Notes: Holding pattern minimums or other time sensitive procedures are listed here.

Communications Frequencies: Maintaining Contact with ATC

This section lists the frequencies required for communicating with Air Traffic Control during the approach.

• Clearance Delivery: For obtaining initial IFR clearance.

• Ground Control: For taxi instructions.

• Tower: For takeoff and landing clearances.

• Approach Control: For communication during the approach phase.

• Missed Approach: Identify the frequencies for communicating after a missed approach.

Lighting Information: Enhancing Visual Acquisition

This section details the available approach and runway lighting systems. Understanding the configuration of these systems can significantly improve your ability to identify the runway environment in low visibility conditions.

• Approach Lighting System (ALS): ALS configurations, such as MALSR, SSALR, or ALSF-2, are detailed here.

• Runway Lighting: This includes information on the intensity and type of runway edge lights, runway end identifier lights (REILs), and centerline lighting.

By systematically decoding each section of the approach plate, pilots can gain a comprehensive understanding of the intended flight path, altitude restrictions, communication procedures, and minimum weather requirements. This knowledge is paramount for ensuring safe and efficient IFR operations.

Putting It All Together: Practical Application of Approach Plates

Instrument approach plates are dense documents, brimming with information crucial for the safe execution of IFR procedures. Mastery lies not only in understanding individual elements, but in synthesizing them into a cohesive mental picture of the intended flight path. This section dissects the practical application of approach plates, guiding you through flight planning and execution phases, while emphasizing proactive decision-making.

The Flight Planning Phase: Building the Foundation

The journey begins well before the aircraft leaves the ground. Effective flight planning, informed by a thorough understanding of the approach plate, is paramount. This initial phase sets the stage for a safe and efficient instrument approach.

First, meticulously review the weather forecast and NOTAMs for the destination airport and alternate(s). Identify any potential hazards, such as icing conditions, thunderstorms, or temporary flight restrictions (TFRs).

Next, select the appropriate approach procedure based on prevailing conditions, aircraft capabilities, and ATC guidance. Analyze the approach plate, paying close attention to:

• Initial Approach Fix (IAF): How to enter the procedure from your current location.
• Course and Distances: Verify magnetic courses and distances between waypoints.
• Minimum Altitudes: Confirm that published minimum altitudes provide adequate obstacle clearance.
• Communications: Identify required frequencies for contacting ATC.
• Missed Approach Procedure: Understand the actions to take if a landing cannot be accomplished.
• Minimums: Assess if the weather is forecast to be at or above minimums for the selected approach.

Finally, calculate required fuel reserves, taking into account the distance to the alternate airport and potential delays. Brief the approach with all crewmembers.

Executing the Approach: A Phase-by-Phase Breakdown

Executing an instrument approach is a dynamic process that requires continuous monitoring and adaptation. Understanding the nuances of each phase – initial, intermediate, final, and missed – is crucial for maintaining situational awareness and ensuring a safe outcome.

The Initial Approach Phase

This phase involves transitioning from the enroute structure to the instrument approach procedure. Key tasks include:

• Cross-checking aircraft position against the planned route.
• Monitoring navigation equipment to ensure accurate tracking.
• Making required radio calls to ATC.
• Complying with ATC instructions.

Adjust airspeed and configuration as necessary to prepare for the intermediate approach.

The Intermediate Approach Phase

This phase aligns the aircraft with the final approach course. Focus on:

• Precisely flying the published course and altitudes.
• Monitoring airspeed and aircraft configuration.
• Completing any required checklists.

Be prepared to make timely adjustments to maintain the desired flight path.

The Final Approach Phase

The final approach phase is the most critical, demanding precise control and unwavering attention. Key considerations include:

• Maintaining the correct glide path or descent angle.
• Closely monitoring airspeed and aircraft configuration.
• Scanning for visual cues as you approach the decision altitude (DA) or minimum descent altitude (MDA).
• Being prepared to execute a missed approach if visual references are not acquired.

Precision approaches (e.g., ILS) offer vertical guidance and lower minimums, whereas non-precision approaches require the pilot to determine the appropriate descent profile. RNAV approaches utilize GPS for navigation, offering greater flexibility and efficiency.

The Missed Approach Phase

The decision to execute a missed approach should be made decisively if visual references are not acquired at the DA/MDA, or if an unsafe condition develops.

• Immediately initiate the climb and follow the published missed approach procedure.
• Notify ATC of the missed approach and your intentions.
• Re-evaluate the situation and determine the next course of action.

Remember, a well-executed missed approach is often safer than a poorly executed landing.

Staying Ahead of the Aircraft: Situational Awareness

Maintaining situational awareness is paramount throughout the instrument approach. This involves continuously monitoring aircraft position, navigation equipment, weather conditions, and ATC communications.

Use all available resources, including:

• Navigation displays
• Autopilot systems
• Electronic flight bags (EFBs)

Anticipate potential problems and develop contingency plans.

CRM: A Critical Element in Multi-Crew Operations

In multi-crew operations, effective Crew Resource Management (CRM) is essential for a safe and coordinated instrument approach.

• Clearly define roles and responsibilities.
• Encourage open communication and feedback.
• Use standard operating procedures (SOPs) to ensure consistency.
• Briefing the approach with all crewmembers helps to ensure that everyone is on the same page.

By fostering a collaborative environment, CRM can help to mitigate errors and improve overall flight safety.

Advanced Considerations and Best Practices: Mastering Instrument Approaches

Instrument approach plates are dense documents, brimming with information crucial for the safe execution of IFR procedures. Mastery lies not only in understanding individual elements, but in synthesizing them into a cohesive mental picture of the intended flight path. This section delves into advanced strategies and best practices that elevate the use of approach plates from a mere procedural task to a nuanced and proactive exercise in flight safety and operational excellence.

The Imperative of Currency: Staying Ahead of the Curve

The aviation landscape is dynamic. Regulations evolve, procedures are updated, and approach plates are revised to reflect these changes. Maintaining currency with these updates is not merely a recommendation; it is a fundamental requirement for safe IFR operations.

Pilots must establish a rigorous system for reviewing new approach plates, understanding the revisions, and integrating them into their flight planning and execution processes. Relying on outdated information can have severe consequences, leading to navigational errors, altitude deviations, and potential conflicts with terrain or other aircraft.

Mitigating Risk: A Proactive Approach to Instrument Flying

Instrument approaches inherently involve a higher degree of risk than visual flight. Reduced visibility, complex procedures, and increased workload can quickly compound, leading to hazardous situations.

Effective risk management is therefore paramount. This involves a thorough assessment of potential hazards before each flight, coupled with the implementation of strategies to mitigate these risks. Key areas of consideration include:

• Weather: Evaluate current and forecast weather conditions along the route and at the destination. Consider the impact of wind, turbulence, icing, and low visibility on aircraft performance and pilot workload.
• Aircraft Performance: Assess the aircraft’s capabilities and limitations, taking into account weight and balance, fuel endurance, and equipment functionality. Be prepared to execute a missed approach if the aircraft cannot meet the required performance parameters.
• Pilot Fatigue: Recognize the detrimental effects of fatigue on cognitive function and decision-making. Ensure adequate rest before each flight, and be willing to postpone or cancel if feeling impaired.
• Regulatory Compliance: Verify all pilot and aircraft documentation is current and in compliance with all relevant regulations.

Navigating the Unexpected: Handling Emergencies with Preparedness

Even with meticulous planning and preparation, unforeseen events can occur during instrument approaches. Equipment malfunctions, sudden changes in weather, or unexpected ATC instructions can quickly escalate into emergency situations.

Pilots must be prepared to respond calmly and decisively to these challenges. This requires a thorough understanding of emergency procedures, proficiency in aircraft systems, and the ability to prioritize tasks effectively under pressure.

Equipment Failures

Practice simulated instrument failures during training flights to develop the skills and reflexes necessary to maintain control of the aircraft and safely execute an emergency landing.

Deteriorating Weather

Establish clear criteria for abandoning an approach if the weather deteriorates below minimums. Have a pre-planned alternate airport in mind, and be prepared to divert if necessary.

The Power of Synergy: Integrating Resources for Enhanced Situational Awareness

Instrument approach plates are not designed to be used in isolation. They are one piece of a larger puzzle that includes weather briefings, NOTAMs, ATC communications, and other navigational resources. Integrating these resources effectively can significantly enhance situational awareness and improve the overall safety of the flight.

• Weather Briefings: Obtain a comprehensive weather briefing before each flight, paying close attention to potential hazards such as icing, turbulence, and low-level wind shear.
• NOTAMs: Review all relevant NOTAMs to identify any temporary flight restrictions, navigational outages, or other potential hazards along the route.
• ATC Communications: Maintain clear and concise communication with ATC, and be prepared to clarify any ambiguous instructions or requests.
• Flight Management Systems (FMS): Use FMS to augment and cross-check navigational data.

By embracing these advanced considerations and best practices, pilots can transcend the rote execution of instrument approaches and cultivate a deeper understanding of the principles and strategies that underpin safe and efficient IFR operations.

So, there you have it – a closer look at approach plate symbology and how it translates to safer, more informed flying. Keep this guide handy, review it often, and remember that mastering approach plate symbology is an ongoing process. Happy (and safe) landings!