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Commercial air transport operations

Ramp inspections

Rules for issuing; maintaining; amending; limiting; suspending or revoking

Privileges and responsibilities

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REACT immediately

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PREPARE for Action

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ACAS - Airborne Collision Avoidance System - a.k.a. - TCAS

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ACAS - Airborne Collision Avoidance System - a.k.a. - TCAS

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Reduces the risk of collision

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Besides altitude (C) it also send the identification and more info

24 BITS

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Should always be ON

In the absence of any ATCdirections on regional air navigation agreements - MODE A 2000

SQUAK IDENT only when requested by ATC

Mode A always ON, however if the aircraft has MODE C - IT”S ALWAYS C THAT STAYS ON

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Start for IFR - FL10
Start for VFR - FL35

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Additional buffer area extends 9.3km( 5.0NM) beyond the boundary of the holding area

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All turns - bank 25 or a rate of 3degrees per second, whichever requires the lesser bank

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All turns - bank 25 or a rate of 3degrees per second, whichever requires the lesser bank

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30Degrees maximum of approaching angle

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All EXAmples of calculations in this documente are 2000 ft agl and +15 c (double ISA)

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Required Navigation Performance (RNP) is a type of performance-based navigation (PBN) that allows aircraft to fly precisely defined paths without the need for ground-based navigation aids. It specifies the level of accuracy, integrity, continuity, and availability needed for a specific operation. Here are the key aspects:

### Key Components of RNP

1. **Accuracy**: The aircraft's ability to stay within a certain lateral and vertical distance from the intended flight path. RNP levels are expressed as a distance in nautical miles (e.g., RNP 0.3 means the aircraft must stay within 0.3 nautical miles of the path).

2. **Integrity**: The ability of the navigation system to provide timely and valid information, ensuring that errors are detected and alerted to the crew.

3. **Continuity**: The capability of the navigation system to perform its function without interruption during a specific operation.

4. **Availability**: The availability of the necessary equipment and signal coverage to perform the navigation.

### Types of RNP Operations

1. **RNP APCH**: Required Navigation Performance Approach, used for approach procedures to airports.

2. **RNP AR APCH**: Required Navigation Performance Authorization Required Approach, which requires special authorization due to the stringent requirements for accuracy and integrity.

3. **RNP 1, RNP 2, etc.**: Different levels of RNP are used for various phases of flight, including enroute, terminal, and approach operations. The number indicates the accuracy in nautical miles.

### Advantages of RNP

1. **Enhanced Safety**: By providing precise flight paths, RNP reduces the risk of controlled flight into terrain (CFIT) and enhances obstacle clearance.

2. **Increased Efficiency**: RNP allows for more direct routes and optimized flight paths, reducing fuel consumption and flight time.

3. **Improved Airspace Utilization**: RNP enables tighter spacing of aircraft, which can increase the capacity of airspace and reduce congestion.

4. **Environmental Benefits**: More efficient routing and descent profiles can lead to lower emissions and reduced environmental impact.

### RNP in Modern Aviation

RNP is part of the broader PBN framework, which includes both RNP and Area Navigation (RNAV). While RNAV provides lateral navigation using waypoints without specific accuracy requirements, RNP adds the dimension of required performance levels, particularly in terms of accuracy and monitoring.

### Implementation and Use

- **Equipment**: Aircraft must be equipped with advanced navigation systems, including GPS and flight management systems (FMS), to meet RNP requirements.
- **Training and Certification**: Pilots and airlines must undergo specific training and certification processes to conduct RNP operations, particularly for RNP AR APCH.
- **Procedures**: Airlines and air traffic control (ATC) must develop and adhere to specific procedures for RNP operations to ensure safety and efficiency.

Overall, RNP represents a significant advancement in aviation navigation, contributing to safer, more efficient, and environmentally friendly flight operations.

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Designated instrument flight rule (IFR)

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When to Do a Procedure Turn | Procedure Turns and GPS | IFR Training

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When to Do a Procedure Turn | Procedure Turns and GPS | IFR Training

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VOR (VHF Omnidirectional Range) is a type of radio navigation system for aircraft, enabling pilots to determine their position and stay on course by receiving radio signals transmitted by a network of fixed ground radio beacons. Here's a brief overview:

How VOR Works
- **Signal Transmission**: VOR stations transmit two signals. One is a reference signal (continuous) and the other is a variable signal (rotates 360 degrees). The variable signal's phase changes as it rotates.
- **Phase Comparison**: The aircraft receiver compares the phase difference between the reference and variable signals. This phase difference corresponds to the aircraft's bearing from the station, known as the radial.
- **Radial Interpretation**: The receiver displays this information to the pilot, indicating the aircraft's position relative to the station and whether it is on the selected radial.

VOR and Modern Navigation
While VOR remains an essential part of air navigation, it is increasingly being supplemented or replaced by more advanced systems like GPS. However, VOR is still maintained as a backup system due to its reliability and independence from satellite signals.

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RNAV (Area Navigation) is a method of navigation that allows an aircraft to fly on any desired flight path within the coverage of ground- or space-based navigation aids, or within the limits of the capability of self-contained aids, or a combination of these. This capability allows for more flexible and efficient use of airspace and more direct routes.

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For RNAV flights - 4000feet
For VOR & NDB - 8000feet

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Minimum descent Altitude or Height - 2D lateral

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RNAV (Area Navigation) is a method of navigation that allows an aircraft to fly on any desired flight path within the coverage of ground- or space-based navigation aids, or within the limits of the capability of self-contained aids, or a combination of these. This capability allows for more flexible and efficient use of airspace and more direct routes.

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Lateral and vertical

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Lateral navigation guidance only

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45 degrees must be between the runaways

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Memorize Holding Pattern Entries for Good

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Memorize Holding Pattern Entries for Good

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4 minutes holding pattern maximum

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System for approach and landing operations utilising GNSS, augmented by a ground based augmentation system

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Radio separation

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Responsibility of investigation
Is in the state where the accident occurs it’s the same state responsible

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From 1992 law changed things completely.

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Weapons could be carried by passengers if they had a license, from then rules stated that these should be handout to the captain.

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The Schengen Agreement is a treaty that led to the creation of the Schengen Area, an area comprising 27 European countries that have abolished passport and other types of border control at their mutual borders.

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Radar position indication with MAP

When available, information obtained from SSR

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IDENT should only be activated if the ATC specifically requests.

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RWY in use
QNH
Visibility if less that 20 km or RVR if applicable
The correct time(watch not anymore, but still necessary something to measure time(phone))

Any significant changes in wind or dangerous weather conditions

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Will get the aircraft ready(engines and ready to go) and then will be passed to Ground

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Tower control, all the aircraft’s flying within the area and runways

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Responsible for traffic on the manoeuvring area except for RUNWAYS

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20NM distance

DME stands for Distance Measuring Equipment. It is a radio navigation aid used in aviation to provide accurate distance information between an aircraft and a ground station. DME operates by measuring the time it takes for a radio signal to travel between the aircraft and the ground station and then calculating the distance based on the speed of light.

DME provides accurate and reliable distance information to pilots, allowing for precise navigation and approach procedures, especially in instrument flight conditions or when radar coverage is limited or unavailable.

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Radio navigation encompasses various ground-based radio navigation aids used in aviation for aircraft navigation. Here are some of the most common types:

1. **VOR (VHF Omnidirectional Range)**: VOR stations transmit VHF radio signals in all directions, allowing aircraft equipped with VOR receivers to determine their radial position relative to the VOR station. VOR navigation is widely used for en-route navigation, instrument approaches, and holding patterns.

2. **NDB (Non-Directional Beacon)**: NDBs transmit low-frequency radio signals in all directions. Aircraft equipped with ADF (Automatic Direction Finder) receivers can determine their bearing or direction relative to the NDB station. NDB navigation is used for en-route navigation and instrument approaches.

3. **DME (Distance Measuring Equipment)**: DME stations provide distance information from the aircraft to the ground station. DME operates in conjunction with VOR or ILS (Instrument Landing System) navigation, providing distance information to the aircraft.

4. **ILS (Instrument Landing System)**: ILS is a precision approach system that provides lateral and vertical guidance to aircraft during the approach and landing phases of flight. It consists of two main components: a localizer for horizontal guidance and a glide slope for vertical guidance.

5. **GPS (Global Positioning System)**: GPS is a satellite-based navigation system that provides accurate positioning and timing information to aircraft equipped with GPS receivers. GPS navigation has become increasingly common and is used for en-route navigation, instrument approaches, and precision approaches.

6. **RNAV (Area Navigation)**: RNAV systems allow aircraft to navigate along predefined routes using onboard navigation equipment, such as GPS or inertial navigation systems. RNAV navigation provides flexibility in route planning and navigation.

These are just a few examples of the many radio navigation aids used in aviation. Each type of navigation aid has its own characteristics, advantages, and limitations, and pilots may use a combination of these aids depending on the requirements of their flight and the available infrastructure.

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Vertical

Longitudinal

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5nm standard minimum distance - radar

RADAR5

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Special air-reports shall be made by all aircraft
Mainly weather observations made by pilots whilst flying

Turbulence
Icing
Mountain Wave
TS with or without hail
Dust storm or heavy sandstorm
Volcanic ash
Pre eruption or eruption activity

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Transponder mode refers to the operating mode of an aircraft transponder, which is a device that responds to radar interrogations by ground-based radar systems or other aircraft. Transponders play a crucial role in air traffic control and surveillance by providing information about an aircraft's identity, altitude, and other parameters to radar controllers.

Here's a comparison of ADS-B, ADS-C, and transponder mode:

**Transponder Mode**:
- Transponder mode refers to the operating mode of an aircraft transponder, which responds to radar interrogations by ground-based radar systems or other aircraft.
- Transponders provide information about an aircraft's identity (Mode A), altitude (Mode C), and other parameters when interrogated by radar.
- Transponders are essential for radar surveillance and air traffic control, providing radar controllers with information about aircraft positions and enabling the safe separation of air traffic.

In summary, ADS-B, ADS-C, and transponder mode are all surveillance technologies used in aviation, but they operate in different ways and serve different purposes. ADS-B and ADS-C provide surveillance independent of radar, while transponders respond to radar interrogations to provide information to air traffic control. Each technology has its own advantages and applications in different types of airspace and operational environments.

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Transponder mode refers to the operating mode of an aircraft transponder, which is a device that responds to radar interrogations by ground-based radar systems or other aircraft. Transponders play a crucial role in air traffic control and surveillance by providing information about an aircraft's identity, altitude, and other parameters to radar controllers.

Here's a comparison of ADS-B, ADS-C, and transponder mode:

**Transponder Mode**:
- Transponder mode refers to the operating mode of an aircraft transponder, which responds to radar interrogations by ground-based radar systems or other aircraft.
- Transponders provide information about an aircraft's identity (Mode A), altitude (Mode C), and other parameters when interrogated by radar.
- Transponders are essential for radar surveillance and air traffic control, providing radar controllers with information about aircraft positions and enabling the safe separation of air traffic.

In summary, ADS-B, ADS-C, and transponder mode are all surveillance technologies used in aviation, but they operate in different ways and serve different purposes. ADS-B and ADS-C provide surveillance independent of radar, while transponders respond to radar interrogations to provide information to air traffic control. Each technology has its own advantages and applications in different types of airspace and operational environments.

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1. **ADS-B**:
- Advantages: Provides real-time, continuous broadcast of aircraft position information. Offers enhanced situational awareness for pilots and air traffic control. Relatively low-cost equipment and easy installation.
- Limitations: Coverage may be limited in remote or mountainous areas without adequate ground stations. Vulnerable to signal interference and spoofing.

2. **ADS-C**:
- Advantages: Can be used in areas without radar coverage, such as oceanic and remote airspace. Operates on a contractual basis, allowing flexibility in reporting intervals. Provides surveillance in areas where ADS-B coverage is limited.
- Limitations: Relies on periodic reporting rather than continuous broadcast, potentially resulting in less frequent updates. Requires data link infrastructure for communication between aircraft and ground stations.

The "best" surveillance technology often depends on the specific operational requirements and objectives. In some cases, a combination of ADS-B and ADS-C may be used to provide comprehensive surveillance coverage across different types of airspace. Additionally, newer technologies such as space-based ADS-B and multilateration systems are being developed to further enhance surveillance capabilities in areas with limited radar coverage.

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ADS-C stands for Automatic Dependent Surveillance-Contract. It is a surveillance technology used in aviation that relies on periodic position reports sent by aircraft to air traffic control (ATC) via satellite communication or other data link systems. Unlike ADS-B, which broadcasts aircraft position information continuously, ADS-C operates on a contractual basis, with aircraft only transmitting position reports when requested by ATC.

ADS-C is commonly used in oceanic and remote areas where radar coverage is limited or nonexistent. It allows for more efficient use of airspace and provides improved surveillance and tracking capabilities for ATC. ADS-C is often used in conjunction with other surveillance technologies, such as ADS-B, to provide comprehensive coverage of aircraft movements.

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ADS-B stands for Automatic Dependent Surveillance-Broadcast. It is a surveillance technology used in aviation that relies on aircraft broadcasting their own GPS-derived position and other relevant information to ground stations and other aircraft. ADS-B Out refers to the transmission of this information from an aircraft, while ADS-B In refers to the reception of this information by other aircraft or ground stations.

ADS-B technology is a key component of modern air traffic management systems and is being mandated by regulatory authorities in many regions as part of efforts to improve airspace efficiency, safety, and situational awareness. It provides more accurate and timely position information compared to traditional radar-based surveillance systems, allowing for more precise tracking of aircraft and better management of air traffic.

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First half hour
After, every hour.

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At every check point as soon as possible

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At every check point as soon as possible

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A position report for an aircraft typically includes essential information about the aircraft's current location, altitude, heading, and other relevant details. Here are some common contents of a position report:

1. **Aircraft Identification**: The unique identifier for the aircraft, such as its registration number or flight number.

2. **Position**: The aircraft's current geographical location, often given in terms of latitude and longitude coordinates or in reference to a navigational waypoint or fix.

3. **Altitude**: The aircraft's current altitude above sea level, expressed in feet or meters.

4. **Heading**: The direction in which the aircraft is pointing, typically given as a compass bearing in degrees (e.g., 045° for northeast).

5. **Speed**: The aircraft's groundspeed, or the speed at which it is moving relative to the ground, often expressed in knots.

6. **Time**: The time at which the position report is made, usually provided in Coordinated Universal Time (UTC).

7. **Additional Information**: Depending on the circumstances and the requirements of air traffic control or other authorities, additional information may be included in the position report, such as the aircraft's intended route, next waypoint, fuel status, and any relevant remarks or observations.

Position reports are essential for maintaining communication and situational awareness between aircraft and air traffic control, especially in areas where radar coverage or other surveillance systems may be limited. They help ensure the safe and efficient operation of air traffic in both controlled and uncontrolled airspace.

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For intermediate positions along the runway - 3 minutes

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For intermediate positions along the runway - 3 minutes

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Waiting time - minimum 2 minutes between Light or Medium

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Waiting time - minimum 2 minutes between Light or Medium

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Heavy.(H) -more than 1360000 kg

Medium (M)- between 7000kg and 136000kg

Light (L) - less than 7000kg

Super (J) - ex A380

When

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ATC, shouldn’t request more than this when on in circuit to land

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-Runway in use
Altimeter settings
SSR codes
Level instructions
Heading and speed instructions
Whether issued by the controller

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STAR stands for Standard Terminal Arrival Route. A STAR is a predefined arrival procedure published by aviation authorities to provide a standard and orderly way for aircraft to transition from the en-route phase of flight to the approach phase for landing at an airport.

STARs typically consist of specific routing, altitudes, and speed restrictions to follow from a designated entry point or fix down to the initial approach fix (IAF) for a particular instrument approach procedure. These procedures help manage the flow of arriving air traffic, sequence aircraft for landing, and ensure safe and efficient operations, especially in busy airspace. Pilots are expected to adhere to STAR procedures unless instructed otherwise by air traffic control.

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A SID, or Standard Instrument Departure, is a predefined departure procedure published by aviation authorities to provide a standard and orderly way for aircraft to depart from an airport, especially in busy airspace or under certain environmental conditions. SIDs are designed to ensure the safe and efficient flow of departing air traffic while minimizing conflicts with other aircraft and obstacles.

SIDs typically consist of specific routing, altitudes, and speed restrictions to follow immediately after takeoff until reaching a specified point or altitude. Pilots are required to comply with SID procedures unless otherwise instructed by air traffic control. Following SIDs helps streamline departures, reduce controller workload, and enhance safety.

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Controller Pilot Data Link Communications (CPDLC)

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CPDLC is a two-way data-link system by which controllers can transmit non urgent 'strategic messages to an aircraft as an alternative to voice communications. The message is displayed on a flight deck visual display.

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Introduction

This article gives an overview of Controller Pilot Data Link Communications (CPDLC). It describes the main principles, the different data link services and the basics of CPDLC operations, including related phraseology. The goal is to provide background information for understanding the safety issues related to this technology.

Definition

Controller Pilot Data Link Communications (CPDLC) is a means of communication between controller and pilot, using data link for ATC communications. (ICAO Doc 4444: PANS-ATM)

Description

CPDLC is a two-way data-link system by which controllers can transmit non urgent 'strategic messages to an aircraft as an alternative to voice communications. The message is displayed on a flight deck visual display.

The CPDLC application provides air-ground data communication for the ATC service. It enables a number of data link services (DLS) that provide for the exchange of communication management and clearance/information/request messages which correspond to voice phraseology employed by air traffic control procedures.

The controllers are provided with the capability to issue ATC clearances (level assignments, lateral deviations/vectoring, speed assignments, etc), radio frequency assignments, and various requests for information.

The pilots are provided with the capability to respond to messages, to request/receive clearances and information, and to report information. A "free text" capability is also provided to exchange information not conforming to defined formats.

The CPDLC is being globally implemented and currently is in different implementation stages. The global communication procedures are detailed in the ICAO Provisions: Annex 10 Volume III Part 1 Chapter 3. The CPDLC message set is contained in ICAO Doc 4444: PANS-ATM, Annex 5.

The implementation of CPDLC for the European airspace users operating above FL285 and ANSPs is addressed in the Data Link Services Implementing Rule.

Data Link Services Implementing Rule

The Data Link Services Implementing Rule (DLS-IR) was adopted on 16 January 2009 by the European Commission and published as Regulation 29/2009 - Data link services for the Single European Sky. The DLS-IR is legally binding and applies directly to Air Navigation Service Providers (ANSPs) and to Aircraft Operators.

Air navigation service providers and operators have reported technical issues when implementing Regulation (EC) No 29/2009, particularly disconnections, known as Provider Aborts ('PAs'), of existing air-ground data communications enabling the operations of data link services ('DLS') and which are beyond acceptable performance levels. For that reason certain air navigation service providers took mitigation measures, consisting of the restriction of DLS operations to aircraft equipped with specific avionics through so-called 'white lists', so as to address potential safety impacts of those PAs in the operations of data link service.

At the request of the Commission, the European Aviation Safety Agency ( EASA) conducted an investigation to identify the root cause or causes of those technical issues and to recommend measures to address them. The investigation revealed that the random PA occurrences could not be attributed to a single, predictable cause but rather to a combination of factors related to the radio frequency environment and to the current single frequency implementation of the data link infrastructure. It was found that this excessive rate of random PAs causes a degradation in the network performance potentially presenting aviation safety risks by increasing the pilots and controllers' workload and creating confusion leading to a loss of situational awareness.

EASA concluded in its investigation report that acceptable data link performance levels can only be established by deploying a multi-frequency infrastructure, which is also to be optimised for radio frequency interference prevention. It recommended establishing and implementing a plan of actions to further investigate the identified technical issues and to validate the necessary technical solutions. However, these measures require time and EASA therefore recommended to reconsider the date of application of Regulation (EC) No 29/2009 and the timeframes of that Regulation.

Therefore, particularly due to the observed technical difficulties and shortcomings in the performance of the deployed DLS infrastructure and their potential impact on aviation safety and given that the necessary studies and actions to identify and remedy them are expected to be completed during the course of 2018, the date of application of Regulation (EC) No 29/2009 has been deferred to 5 February 2018 as stated in Regulation 310/2015 amending Regulation No 29/2009 on data link services for the SES.

Data Link Services

The following data link services are available:

Data Link Initiation Capability (DLIC) - this service provides the necessary information to make data link communications possible between an ATSU and aircraft. The DLIC service is executed prior to the first use of any other data link application.

ATC Communications Management Service (ACM) - this service provides automated assistance to flight crew and controllers for the transfer of ATC communications (voice and CPDLC).

ATC Clearances Service (ACL) - this service allows flight crews and controllers to conduct operational exchanges - flight crews can send requests and reports and controllers can issue clearances, instructions and notifications.

ATC Microphone Check Service (AMC) - this service allows controllers to send an instruction to all CPDLC capable aircraft on a given frequency (at the same time) to verify that their voice communication equipment is not blocking a given voice channel.

Departure Clearance (DCL) - this service provides automated assistance for requesting and delivering departure clearances to aircraft.

Downstream Clearance Service (DSC) - this service is provided for flight crews who are required to request and obtain clearances from ATS units that are not yet in control of the aircraft when they cannot get the clearance information via the current ATS unit through unit to unit coordination.

The DLS-IR mandated the implementation of the the first four services only, notably DLIC, ACM, ACL and AMC.

Expected Benefits of CPDLC

Less communication on the ATC frequency;

Increased sector capacities;

More pilot requests can be dealt with simultaneously;

Reduced probability of miscommunication (e.g. due call sign confusion);

Safer frequency changes, hence fewer loss of communication events.

Main Principles of CPDLC Exchange

The following underlying principles are applicable to the use of CPDLC:

Voice and data link shall co-exist as a means of ATS communication. Implementation of CPDLC is intended as a supplementary means of communication to the use of voice communication.

CPDLC shall only be used in the context of non-time-critical communications. Time-criticality is mainly determined by the following factors: ATC traffic situation, end-to-end performance (systems and flight crew/controller response time) and recovery time. Users should be aware that while a voice response is generally expected in a few seconds the latency of CPDLC is usually much longer (up to several minutes).

The decision to use either voice or CPDLC shall be at the discretion of the controller and/or pilot involved.

The provisions regarding the use of CPDLC shall respect the following standard as provided in ICAO Annex 11, Chapter 3, par. 3.5.1: "A controlled flight shall be under the control of only one air traffic control unit at any given time".

CPDLC Operations

Flight planning. Operators of CPDLC capable aircraft shall insert the letter J and a corresponding number (1 for ATN VDL mode 2, 2-7 for different FANS implementations) in Item 10 and COM/CPDLC in Item 18 of the ICAO flight plan form. More than one of these can be inserted depending on the aircraft equipment (e.g. J1J2 means the aircraft is equipped with both ATN VDL mode 2 and FANS 1/A HFDL).

Transfer of CPDLC. If an aircraft is transferred from an ATS unit where CPDLC is not available to an ATS unit where CPDLC is available, the aircraft uses DLIC to log on to the unit that is CPDLC equipped. The procedures and timings are detailed in the respective AIP.

If both adjacent ATS units are using CPDLC the transfer of voice communications and CPDLC commences concurrently. The transferring unit being the Current data authority (CDA) designates the receiving unit as Next data authority (NDA). The purpose of this designation is to reduce the possibility of logging on to an improper data authority (which is equivalent to switching to the wrong radio frequency in voice communications).

If an aircraft is transferred from an ATS unit where CPDLC is available to an ATS unit where CPDLC is not available, CPDLC termination commences concurrent with the transfer of voice communications.

Use of CPDLC. The extent to which CPDLC can replace voice communications is largely subject to local implementation choices. Although the technology allows a wide array of complex messages the most commonly used are:

Change of SSR code;

Transfer of control and communication;

ATC clearances (e.g. level changes, vectoring, direct routing, speed control) that are not time-critical;

Response to aircraft CPDLC requests;

CPDLC message composition.The messages are composed in standard format, in plain language or in abbreviations and codes, as prescribed in Annex 10, paragraph 3.7. Plain language should be avoided when the length of the text can be reduced by using appropriate abbreviations and codes. Nonessential words and phrases, such as expressions of politeness, are not to be used. Sets of mandatory and optional uplink (ground-to-air) and downlink (air-to-ground) messages have been developed for each data link service. It is therefore possible that either the airborne or the ground system supports a larger array of messages. Proper handling of unsupported messages (e.g. responding with appropriate error messages) is an essential part of CPDLC system development and implementation.

CPDLC messages can be single element or multi-element. A maximum of 7 elements in one message is allowed according to ICAO ATN SARPs and the EUROCAE-Document ED-110B. Systems compliant to the EUROCONTROL Specification [1] should allow downlink messages, containing maximum 2 elements.

Example of a single element message: CLIMB TO [level].

Example of a multi-element message: CLIMB TO [level], CLIMB AT [vertical rate] MINIMUM.'

A single element message response to a multi-element message applies to all message elements. If any part of a multi-element message cannot be complied with, the pilot shall send an "UNABLE" response for the whole message (which means that the pilot will not comply with any of the message elements). This could result in an unnecessarily prolonged communication exchange. Therefore the use of messages with multiple elements should be avoided where possible. They should be used when it is necessary to execute the set of clearances or instructions in its entirety (dependent clearances).

Only one open dialogue of the same type with the same aircraft at any given time is allowed. The possible types are:
It is possible to have open dialogues for a speed restriction and a level change with one aircraft at the same time. It is not possible to have open dialogues for a heading and a direct route with one aircraft at the same time.
Reverting from CPDLC to Voice

Usually when a controller or pilot communicates via CPDLC, the response should be via CPDLC. When a controller or pilot communicates via voice, the response should be via voice. The following circumstances describe potential situations where the air ground communications should revert to voice:

When it is required to clarify the meaning or the intent of any unexpected, inappropriate or ambiguous CPDLC message;

When it is necessary to ensure the timely execution of an instruction issued by CPDLC;

When corrective actions are required with respect to unintended messages that have been sent using CPDLC;

When a system generates a time-out or an error for a CPDLC message.

CPDLC Related Phraseology

When voice communication is used to correct a CPDLC message the following phrase is used:

(call sign) DISREGARD CPDLC (message content or type) MESSAGE, BREAK, (corrected message).

Example: BTD123 DISREGARD CPDLC CLIMB MESSAGE, BREAK, CLIMB FLIGHT LEVEL 310.

When receiving an alert for a single CPDLC message failure, the controller or pilot either confirms via voice the actions that will be undertaken with respect to the related dialogue, prefacing the information with the phrase '"CPDLC MESSAGE FAILURE" or uses CPDLC to reissue the message that failed.

When receiving an alert that CPDLC has failed the controller or pilot should revert to voice, and inform the other side using the phrase "CPDLC FAILURE".

In case of a complete CPDLC ground system failure the controller should use a general call: ALL STATIONS CPDLC FAILURE (unit name).

When a controller requires all stations or a specific flight to avoid sending CPDLC requests for a limited period of time, the following phrase shall be used: ((call sign) or ALL STATIONS) STOP SENDING CPDLC REQUESTS [UNTIL ADVISED] [(reason)]

The resumption of the normal use of CPDLC shall be advised by using the following phrase: ((call sign) or ALL STATIONS) RESUME NORMAL CPDLC OPERATIONS

SKYclip

Related Articles

Further Reading
ICAO European Commission EUROCONTROL FAA
References

^ EUROCONTROL Specification on Data Link Services, Edition 2.1, January 2009.

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Controller Pilot Data Link Communications (CPDLC)

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CPDLC is a means of communication between pilots and controllers using data link to exchange short messages.

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Unique comb of 24 bits available for assignment to an aircraft for the purpose of air-ground communications

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Great website with current European airspace, delayed flights causes, predicted daily

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Service establish with the objective of contributing to Safe, orderly and expeditious flow of air traffic by ensuring that ATC cavity is ruse to the maximum extent possible and that the traffic volume is compatible with capacities declared by the appropriate ATS authority

It’s implemented where there’s high traffic demand

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RVSM (Reduced Vertical Separation Minimum) and VSM (Vertical Separation Minimum) are both standards used in aviation to increase airspace capacity and efficiency by reducing the vertical separation between aircraft. However, they operate at different flight levels and have different separation standards:

1. RVSM: RVSM applies to altitudes between FL290 (Flight Level 290) and FL410. In RVSM airspace, the standard vertical separation between aircraft is reduced from 2,000 feet to 1,000 feet. This allows for more aircraft to operate in the same airspace, increasing capacity and efficiency.

2. VSM: VSM typically applies to altitudes below FL290. The standard vertical separation between aircraft in non-RVSM airspace is 2,000 feet. VSM is used in airspace where RVSM standards are not implemented or applicable.

In summary, RVSM is used at higher flight levels (FL290 to FL410) with reduced vertical separation, while VSM is used at lower flight levels (below FL290) with standard vertical separation.

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Regional Supplementary Procedures

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Guarded continuously by all ACCs and FICs

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Must acknowledge and record the position to the craft in distress if given

Take a bearing on the transmission

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Following the alert phase, widespread evidence indicates to urgency

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Failed communication - when cleared to land 5 min.

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Failed communication - reference time 30 min