Regulations and Control
Not publishedof exam
Operating Procedures
Not publishedof exam
Emergency Communications
Not publishedof exam
MAYDAYPAN PANDistress RelayRadio SilenceCancellation
Equipment and Frequencies
Not publishedof exam
ConnectionsFusesStation LicencesFrequency BandsEmergency Frequency
Quick Facts
- Certificate
- ROC-A
- Authority
- ISED Canada
- Exam basis
- RIC-21
- Official written exam
- 25 questions
- Pass mark
- 70% or more
- Materials
- Closed book
- Examiner
- ISED-accredited examiner
- Possible exercises
- Written, practical, oral
- Certificate term
- Life
- Revalidation
- Not required
- Exam time
- Not published
- Domain weights
- Not published
Top Six Priorities
Distress, urgency, direction, safety, weather, regularity.
DistressUrgencyDirection-findingFlight SafetyMeteorologicalFlight Regularity
Ground-Air vs Air-Air Control
Ground-Air
- Ground station normally controls
- Aircraft follows instructions
Air-Air
- Called aircraft controls
- Calling aircraft follows
Priority-call initiator overrides normal control.
Certificate and Exam
- Certificate purpose
- Aeronautical radio operation
- Covered stations
- Aircraft and aeronautical land stations
- Exam administrator
- ISED-accredited examiner
- Official written exam
- 25 random questions
- Passing score
- 70% or more
- Written materials
- Closed book
- Possible exercises
- Written, practical, oral
- Eligibility
- No age or nationality restrictions
- Identification
- Presented at examination
- Certificate validity
- Issued for life
Communication Priority
- Priority 1
- Distress communications
- Priority 2
- Urgency communications
- Priority 3
- Radio direction-finding
- Priority 4
- Flight safety messages
- Priority 5
- Meteorological messages
- Priority 6
- Flight regularity messages
- Priority 7
- United Nations Charter messages
- Priority 8
- Priority government messages
- Priority 9
- Telecommunication service communications
- Priority 10
- Other aeronautical communications
Control and Discipline
- Ground-air control
- Ground station normally controls
- Aircraft-aircraft control
- Called aircraft controls
- Priority-call control
- Initiating station controls
- Aircraft station operation
- Pilot or responsible person controls
- Privacy duty
- Preserve communication privacy
- Privacy exceptions
- Distress, urgency, safety, ALL STATIONS
- Prohibited communications
- Superfluous, profane, obscene
- Permitted interruption
- Higher-priority traffic only
- False distress
- Knowingly transmitting is prohibited
Routine Call Order
You, THIS IS, me, frequency, OVER.
Called StationTHIS ISCalling StationFrequencyOVER
OVER vs OUT
OVER
- Transmission finished
- Reply expected
OUT
- Conversation finished
- No reply expected
Never combine OVER and OUT.
Routine Radio Exchange
- Before calling→Listen for interference
- Channel clear→Say called station first
- Identify origin→Say THIS IS
- Continue call→Give own call sign
- Before inviting reply→Give transmitting frequency
- Invite reply→Say OVER
- Message complete→Say OUT
Speech, Time, and Numbers
- Speech rate
- Constant, neither fast nor slow
- Speech rhythm
- Ordinary conversation rhythm
- Filler sounds
- Avoid er and um
- Time format
- Four-figure, twenty-four-hour clock
- Standard time
- UTC avoids zone confusion
- Local time
- Allowed within one zone
- Date-time group
- Day plus four-figure time
- Most numbers
- Pronounce every digit separately
- Whole thousands
- Digits then thousand
- Decimal point
- Say decimal
- Aircraft headings
- Use three digits
- Flight levels
- Use separate digits
Readability Scale
Bad, poor, fair, good, excellent.
1 Bad2 Poor3 Fair4 Good5 Excellent
ROGER vs WILCO
ROGER
- Transmission received
- Compliance not promised
WILCO
- Instructions understood
- Compliance promised
Receipt differs from compliance.
ITU Phonetic Alphabet
- A
- Alfa
- B
- Bravo
- C
- Charlie
- D
- Delta
- E
- Echo
- F
- Foxtrot
- G
- Golf
- H
- Hotel
- I
- India
- J
- Juliett
- K
- Kilo
- L
- Lima
- M
- Mike
- N
- November
- O
- Oscar
- P
- Papa
- Q
- Quebec
- R
- Romeo
- S
- Sierra
- T
- Tango
- U
- Uniform
- V
- Victor
- W
- Whiskey
- X
- X-ray
- Y
- Yankee
- Z
- Zulu
CORRECTION vs SAY AGAIN
CORRECTION
- Sender made error
- Correct version follows
SAY AGAIN
- Receiver requests repetition
- Missing transmission repeated
Fix yours; request theirs.
Procedure Words
- ACKNOWLEDGE
- Confirm receipt and understanding
- AFFIRM
- Yes
- CORRECTION
- Transmission error follows
- DISREGARD
- Treat transmission as unsent
- GO AHEAD
- Proceed with message
- I SAY AGAIN
- Repeat for clarity
- MONITOR
- Listen on frequency
- NEGATIVE
- No or incorrect
- OUT
- Conversation ended; no response
- OVER
- Transmission ended; response expected
- READ BACK
- Repeat exactly as received
- ROGER
- Last transmission received
- SAY AGAIN
- Repeat last transmission
- STANDBY
- Wait; caller will return
- WILCO
- Received, understood, will comply
- WORDS TWICE
- Send each word twice
Calling and Replies
- Before transmitting
- Listen for harmful interference
- Called station
- Speak identifier first
- Calling separator
- Say THIS IS
- Calling station
- Speak identifier next
- Transmitting frequency
- Speak before OVER
- Invitation
- Finish initial call with OVER
- Ready reply
- Use GO AHEAD
- Delayed reply
- Use STAND BY
- Unknown caller
- STATION CALLING, SAY AGAIN
- Communication ending
- Finish with OUT
- Transmission correction
- CORRECTION, last correct phrase
- Message planning
- Plan before transmitting
Signal Checks
- Check duration
- Maximum ten seconds
- Test identity
- Transmit station call sign
- Scale 1
- Bad; unreadable
- Scale 2
- Poor; intermittently readable
- Scale 3
- Fair; difficult reading
- Scale 4
- Good; readable
- Scale 5
- Excellent; perfectly readable
- Airborne test
- Signal check
- Before departure
- Preflight check
- Ground maintenance
- Maintenance check
Distress Message Core
Nature, help, intentions, position, people, details.
NatureAssistanceIntentionsPositionPersonsRescue Details
MAYDAY vs PAN PAN
MAYDAY
- Grave and/or imminent danger
- Immediate assistance required
- Absolute priority
PAN PAN
- Urgent safety concern
- No immediate assistance
- Below distress priority
Match signal to assistance urgency.
Distress Response
- Grave and/or imminent danger→Declare MAYDAY
- Current channel works→Transmit there first
- Contact fails→Try 121.5 MHz
- Message transmitted→Listen for acknowledgment
- No acknowledgment→Repeat distress message
- Distress traffic interfered→Impose radio silence
Distress Procedures
- Distress condition
- Grave and/or imminent danger
- Distress signal
- MAYDAY three times
- First frequency
- Air-ground frequency currently used
- Emergency frequency
- 121.5 MHz
- Distress priority
- Absolute priority
- Distress message prefix
- MAYDAY once
- Immediate follow-on
- May omit signal and call sign
- Message essentials
- Nature, help, intentions, position
- Additional details
- Persons, injuries, rescue information
- Distress traffic
- MAYDAY precedes each transmission
- Acknowledgment ending
- RECEIVED MAYDAY
- Relay signal
- MAYDAY RELAY three times
- Control silence
- SEELONCE MAYDAY
- Other-station silence
- SEELONCE DISTRESS
- End distress silence
- SEELONCE FEENEE
Hearing Priority Traffic
- Hear MAYDAY→Stop interfering transmissions
- Distress unacknowledged→Consider distress relay
- Help remains necessary→Relay distress message
- Hear PAN PAN→Avoid urgency interference
- No urgency message→Listen three minutes
- Action no longer needed→Cancel urgency message
Urgency Procedures
- Urgency condition
- Safety concern; no immediate help
- Urgency signal
- PAN PAN three times
- Urgency authority
- Person in charge
- Urgency priority
- Below distress; above others
- Initial frequency
- Air-ground frequency currently used
- Backup frequency
- 121.5 MHz or available frequency
- Listen after signal
- At least three minutes
- Message elements
- Nature, intentions, position, details
- Cancellation addressee
- ALL STATIONS
Certificate vs Station Licence
ROC-A
- Operator certificate
- Issued for life
Station licence
- Radio authorization
- May have exemption
Operator authority differs from station authorization.
Equipment and Licensing
- Connections
- Keep tight and clean
- Weather protection
- Silicone prevents corrosion and water
- Short circuit
- Bare conductors touching
- Open wire
- Conductor broken inside covering
- Fuse replacement
- Never use higher rating
- Blown fuse
- Correct fault before replacement
- Fuse safety
- Keep hands dry
- Station licence
- Required unless exempt
- Licence inspection
- Make licence available
- Licence contents
- Call sign, frequencies, conditions
Frequency Assignments
- 108.1000–111.9750 MHz
- Aeronautical radionavigation
- 111.9750–117.9750 MHz
- Aeronautical radionavigation
- 117.9750–121.9625 MHz
- Air traffic control
- 121.9825–123.5875 MHz
- General aviation communications
- 123.5875–128.8125 MHz
- Air traffic control
- 128.8125–132.0125 MHz
- Aeronautical operational control
- 132.0125–136.0000 MHz
- Air traffic control
- 121.5 MHz
- Aeronautical emergency frequency
Common Traps
MAYDAY Is Not PAN PAN
Immediate assistance required ≠ No immediate assistance
OVER Is Not OUT
Reply expected ≠ No reply expected
ROGER Is Not WILCO
Receipt confirmed ≠ Compliance promised
Repeat Is Not Standard
Use SAY AGAIN ≠ Avoid REPEAT
Call Sign Order Matters
Called station first ≠ Calling station second
Emergency Frequency Is Backup
Current frequency first ≠ Then 121.5 MHz
Higher Fuse Is Unsafe
Use rated fuse ≠ Never increase rating
Last Minute
- 1.MAYDAY = immediate assistance
- 2.PAN PAN = urgent safety
- 3.Distress outranks every transmission
- 4.Use current frequency first
- 5.121.5 MHz is emergency backup
- 6.Called station comes first
- 7.OVER expects a reply
- 8.OUT expects no reply
- 9.Signal checks: ten seconds maximum
- 10.Readability runs one through five
- 11.Use phonetics for call signs
- 12.Never install higher-rated fuses
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