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Standard Calls (OGHFA BN)
|Content source:||Flight Safety Foundation|
|Operator's Guide to Human Factors in Aviation|
Clear and precise communication among crewmembers is essential for maintaining situational awareness and thereby maximizing the safety of flight. This briefing note discusses the important role that standard calls play in generating effective two-way communication.
Standard phraseology is essential to ensure effective crew communication, particularly in today’s operating environment, which increasingly features:
- Two-pilot operation
- Culturally diverse crewmembers having different native languages and functioning in operating environments around the world
Standard calls include commands and responses predefined to be precise and unambiguous so that information transfer is maximized and situational awareness is maintained. The use of standard calls results in timely, effective and efficient crew coordination. The absence of a standard call at the appropriate time, or the omission of an acknowledgement of a standard call, may result in loss of situational awareness with an associated increase in safety risk.
Standard calls may need to be tailored to specific:
- Aircraft models — based on flight deck and systems design
- Airlines — to suit their operating philosophy and standard operating procedures (SOPs)
- Regulatory requirements and notices to airmen (NOTAMs)
The Flight Safety Foundation Approach and Landing Accident Reduction (ALAR) Task Force found that an absence of standard calls was a factor in approach and landing accidents and serious incidents worldwide. These data clearly point to the consequences of poor communications that lead to a loss of situational awareness and poor crew coordination. The Foundation has also noted that insufficient horizontal or vertical situational awareness or inadequate understanding of prevailing conditions is a causal factor in more than 50 percent of approach and landing accidents.
4 Design and Use of Standard Calls
Standard calls should be alerting or attention-getting in order to be:
- Clearly identified by the listener, the pilot flying (PF) or the pilot not flying (PNF)
- Readily distinguishable from other intra-cockpit or air traffic control (ATC) communications
- Given appropriate priority among all of the other information competing for a pilot’s attention
Standard calls must convey required information with a minimum of words and an unambiguous meaning for all crewmembers. The clarity inherent in a standard call and its acknowledgement reduces the risk of tactical (short-term) decision-making errors (e.g., in selecting modes, setting targets, selecting aircraft configurations).
Standard calls are used to:
- Give a command
- Delegate a task
- Acknowledge a command
- Initiate or complete the transfer of information (prompt or response)
- Ask a question
- Call out a change of indication (e.g., a mode transition or reversion)
- Identify a specific event (e.g., crossing an altitude or flight level)
The importance of using standard calls increases under high workload situations such as critical flight phases and abnormal or emergency situations. The clarity and efficiency of standard calls are essential when there is little time to explain what is said.
In addition to being concise and unambiguous, standard calls should be in harmony with the design and operating philosophy of the aircraft, airline SOPs and applicable regulations. They should also be consistent with the cultural patterns and idioms of the range of crewmembers likely to be flying.
Standard calls should be included in the flow sequence of a company’s SOPs (or summarized at the end of the SOPs) and should be illustrated in the flight patterns published in the (company aircraft operating manual AOM) or quick reference handbook (QRH).
Standard calls should be performed in accordance with the defined PF/PNF task-sharing for the type of operation the crew selects (e.g., hand flying versus autopilot operation) and the type of conditions encountered (e.g., normal versus abnormal or emergency).
Training and SOPs should acknowledge that crewmembers sometimes forget to give a standard call. If a standard call is omitted by one crewmember, good crew resource management (CRM) practice dictates that the other crewmember should suggest the call if the omission is noted. The absence of a standard call at the appropriate time or the absence of an acknowledgment may be the result of a system or equipment malfunction or the incapacitation of a crewmember. Therefore, flight crews should always announce and correct missed calls or responses to maintain situational awareness.
Standard calls may be generated automatically by aircraft systems using synthetic voice messages (e.g., radio-altimeter callouts, ground-proximity warning system/terrain awareness and warning system (GPWS/TAWS) alert messages, reactive or predictive wind shear alert messages). This standardizes the message and eliminates the chance of error in the terminology used. Because systems may fail, however, a needed callout may still be omitted. If there is a system malfunction, the PNF should verbally make the appropriate standard call.
5 Examples of Standard Calls
Many standard calls are universal or generic and can be adopted by virtually all airlines and used by all pilots. Others are specific to particular aircraft, operators, operating environments and events.
5.1 Universal standard calls
The following standard calls are widely used to issue or respond to a command:
- “Check” (or “Verify”)
- a command for the other pilot to check or validate an item
- a confirmation that an item has been validated
- a response confirming that information has been validated at both pilot stations
- a command for the other pilot to input a target value or configuration
- a command for the other pilot to arm an autopilot (AP) or flight director (FD) mode (or to arm a system)
- a command for the other pilot to select an AP/FD mode (or to initialize
- “(System Name) On/Off”
- “on” or “off” following the name of a system is either:
- a command for the other pilot to select/deselect the announced system, or
- a response confirming the status of the system
- “on” or “off” following the name of a system is either:
5.2 Situations requiring specific standard calls
Some standard calls must be based on the specifics of an aircraft’s design or an airline’s operations. The following situations can benefit from the definition and use of specific standard calls:
- Flight crew/ground personnel communications
- Engine start sequence
- Thrust setting
- Specific event-markers during the takeoff phase
- Landing gear and slats/flaps selection (retraction or extension)
- Initiation, interruption, resumption and completion of normal paper or electronic checklists
- Initiation, sequencing, interruption, resumption and completion of abnormal and emergency paper or electronic checklists
- AP or FD engagement
- Manual AP mode engagement
- Mode transitions and reversions (annunciation of flight-mode annunciator (FMA) changes)
- Target selections confirmation (annunciation of indications on the primary flight display (PFD) and/or navigation display (ND) scales)
- Capture phases (e.g., annunciation of navigation leg, radial, localizer, glideslope)
- Altimeter setting changes
- Approaching the cleared altitude or flight level
- Traffic-alert and collision avoidance system (TCAS) traffic advisory (TA) or resolution advisory (RA)
- PF/PNF transfer of controls
- Specific points/targets along the instrument approach path
- Excessive deviation from the typical value of a flight parameter
- Unstabilized approach when reaching the applicable stabilization height or if the approach becomes destabilized below the applicable stabilization height
- Approaching and reaching minimums
- Acquisition or loss of visual references
- Landing or go-around decision
- Specific event markers during the landing roll
- Communication between the flight crew and cabin crew covering both normal conditions (departure and arrival) and abnormal or emergency situations (e.g., cabin depressurization, on-ground emergency evacuation, crew incapacitation, forced landing or ditching, etc.)
6 Standard Calls and Automation
The use of standard calls is of paramount importance for the optimum use of automation (e.g., to promote awareness of arming or engaging modes by calling FMA changes, target selections, FMS entries). Standard calls should support automation by:
- Immediately generating the question “What do I want to fly now?” and, thus, lead to a clear indication of:
- which mode the pilot wishes to arm or engage
- which target the pilot wishes to set
- Clearly transmitting the intention of the PF to the PNF, thereby facilitating:
- cross-check of the FMA and PFD/ND, as applicable
- teamwork (crew coordination), cross-check and backup between the pilots
7 Harmonization of Standard Calls
When an airline operates multiple types of aircraft, there can be benefits to harmonizing standard calls across the fleet, whether the fleet is uniform or mixed. The quest for commonality, however, should not constrain the development of the best possible standard calls for each aircraft type. Cockpit layouts and systems can vary widely, making it difficult or impossible to develop an optimum universal standard call.
The harmonization of standard calls across fleets becomes essential when crewmembers rotate among the different aircraft types (e.g., for communication between cockpit and cabin or between cockpit and ground). Within the cockpit of aircraft with cockpit commonality, however, pilots must use those standard calls most appropriate for that particular flight deck and systems design.
When defining standard calls, standardization must be carefully balanced with the primary goal of operational efficiency and effectiveness.
8 Key Points
- Standard calls promote effective crew interaction and communication, which are needed for good situational awareness and safety of flight.
- The call/command and the response/acknowledgement are of equal importance
to support timely and correct action.
- Standard calls support the rapid and unambiguous transfer of information between crewmembers and the confirmation that the information was correctly received.
- Some standard calls are universal or generic, while others must be tailored to the specific design of the aircraft, its operations and its operating environment.
- An airline may need multiple sets of standard calls to cover all aircraft types and configurations they use.
- Harmonization of standard calls across fleets is desirable, but should not be allowed to degrade the effectiveness of the calls themselves.
9 Associated OGHFA Material
- Adherence to SOPs
- Automated Cockpit Guidelines
- Normal Checklists and Crew Coordination
- Managing Interruptions and Distractions
10 Additional Reading Material and Website References
- International Civil Aviation Organization (ICAO). Annex 6, Operation of Aircraft; Part I, International Commercial Air transport — Aeroplanes; Appendix 2, 5.13.
- ICAO, Preparation of an Operations Manual (Doc 9376).
- Joint Aviation Requirements — Operations (JAR-OPS) 1.1045 and associated Appendix 1, Operations Manuals — structure and contents.
- U.S. National Transportation Safety Board (NTSB). Special Report NTSB-AAS-76-5: Special Study: Flight Crew Coordination Procedures in Air Carrier Instrument Landing System Approach Accidents.
- Airbus SOP Briefing Note - Standard Calls