EASA ATPL — Communications (090) Exam Prep

Correct answer: B. MAYDAY, MAYDAY, MAYDAY, (station called), (aircraft callsign), nature of distress, intention, position, altitude, souls on board, fuel remaining

The ICAO standard distress call begins with 'MAYDAY' spoken three times, followed by the station being called (if time permits), own callsign, nature of the emergency, intention of the pilot-in-command, present position, altitude/flight level, number of persons on board (souls), and fuel remaining (in time). The aircraft should squawk 7700 on the transponder. 'PAN PAN' (spoken three times) is used for urgency situations, not distress.

Correct answer: B. 7600

The transponder code for radio communication failure is 7600. The three emergency transponder codes are: 7500 = unlawful interference (hijack); 7600 = radio communication failure; 7700 = general emergency (distress). Code 2000 is the standard conspicuity code assigned when entering a secondary surveillance radar area without a specific code assignment. These codes are recognised internationally under ICAO standards.

Correct answer: B. The ICAO phonetic alphabet used to spell out letters clearly to prevent misunderstanding

The ICAO phonetic alphabet (Alpha, Bravo, Charlie, Delta, etc.) is used in radiotelephony to spell out letters clearly, preventing misunderstanding caused by similar-sounding letters. This is particularly important for communicating callsigns, waypoints, and registration marks. Each word was chosen for distinctiveness across different languages and radio transmission quality. This alphabet is standardised in ICAO Annex 10 (Volume II).

Correct answer: B. A ground station to alert a specific aircraft on HF radio using a unique four-tone code

SELCAL allows a ground radio station to alert a specific aircraft by sending a unique four-tone code on HF (or VHF) radio. Each aircraft is assigned a unique SELCAL code registered with ICAO. When the aircraft's code is transmitted, the airborne SELCAL decoder triggers an aural and visual alert. This allows the crew to turn down the HF radio volume (HF is noisy) and only be alerted when they are specifically called, reducing crew fatigue during long oceanic flights.

Correct answer: B. Digital data link communication between aircraft and airline operations, including ATIS, METAR, flight plan uplinks, and operational messages

ACARS is a digital data link system that enables the exchange of text-based messages between the aircraft and ground stations (airline operations centres, ATC). It can carry D-ATIS (digital ATIS), weather information (METAR/TAF), flight plan amendments, fuel data, maintenance reports, and CPDLC (Controller-Pilot Data Link Communications) messages. ACARS uses VHF, HF, or SATCOM as the communication medium. It was a precursor to the broader ATN (Aeronautical Telecommunication Network).

Correct answer: B. It reduces frequency congestion, eliminates read-back errors, and provides a permanent record of clearances

CPDLC is a text-based data link between ATC and the flight crew. Its primary advantages include: reduced VHF/HF frequency congestion (critical in busy airspace and oceanic areas), elimination of mishearing/read-back errors (messages are displayed as text and can be reviewed), a permanent record of all exchanges, and the ability to send pre-formatted clearances that can be loaded directly into the FMS. It is mandatory in certain airspace, including NAT HLA (High Level Airspace) and parts of European airspace.