Aeronautical phraseology

Set of communication rules of simplified English language (given, by definition by ICAO), adjusted for simpler (by grammar, semantics and phonetics), non-conflictial and standardized, clear and efficient way of substantial inter-understanding between Air Traffic Control Officer and Pilot-in-Command, between Air Traffic Control Officer and other Air Traffic Control Officer or between one Pilot-in-Command and other Pilot-in-Command, intended solely for professional aviation use, for the best theoretical and practical flight safety performance, at given level of aviation technology.

Semantic and operational strategy, scope and rules

Radio communication in aeronautical phraseologic way, is, by practical circumstances, a very predictable set of situations, and due the nature of one-channel communication, where incursions in conversation can occur in quite significant share of possible situations and in everyday practice (so called "stuck mike" or "clipped transmission"), to "pre-understand" (purport) way of hierarchy and strategy in this communications, is absolutely essential, and some of that is:

By definition, in ICAO documents, ATCO's right to give orders to the pilot is primary.
By the same definition, Pilot-in-Command (P-i-C) has ultimate right to decide upon the order from ATCO ("Pilot's Discretion").
Way of "pre-understanding" by ATCO's side is that ATCO ALWAYS gives an INDIRECT ORDER (command) to P-i-C, and in the same time, it gives announcement to all the interested pilots, an information about what is given to specific P-i-C, considering - what all the rest of present pilots should have in mind, regarding theirs future actions and "tactical plans" during present flights.
Way of "pre-understanding" by P-i-C side is that he or she shall COMPLY TO THE ORDER by ATCO, if not STATED OPPOSITE.
During all the calls to given subject of conversation (by ATCO, or by P-i-C) it should be understood that PHYSICAL RADIO-COMMUNICATION IS PROBABLE, BUT NOT ABSOLUTELY ASSURED.
Some specific words must have unique aeronautical meaning due fact that during previous cca 100 years of air traffic new occasions and not-foreseen situations have been occurring, with catastrophic aftermaths (if conversation is done under "common English language" rules), and at given level of aviation technology, including present TCAS II collision avoidance system, advantage is somewhere and sometimes given to the technology instead to the human factor. (e.g. : "roger" means -> "we have received all of yours last transmission" or, in wider context : "we have understood and we shall proceed as expected" or "you have to understand and you shall proceed as expected", in comparison to "wilco" , meaning "we shall comply")
Deviation from Aeronautical Phraseology's rules and switch to standard English language IN EMERGENCY SITUATIONS is not prohibited, but should be confined-by-time during conversations, since ICAO 4444^{[permanent dead link‍]} document basic rule is TIME SEPARATION between subjects which are trafficking in controlled airspace, so time management and efficiency during Aeronautical Phraseology's conversations is always essential.

Further, ICAO Annex 10, Vol. 2 specifies some of technique and skills for efficient aeronautical phraseology performance:

a. listen out on frequency to ensure no interference from another station

b. place microphone directly in front of your mouth

c. do not turn away from microphone while transmitting

d. use normal conversational voice, speak clearly and distinctly

e. maintain an even rate of speech (not exceeding 100 words per minute)

f. maintain speaking volume at an even level

g. use a slight pause before and after numbers to ensure understanding

h. avoid using long hesitations

i. depress microphone fully, release after complete, avoid clipped transmissions

j. avoid pleasantries

Apart from the above mentioned, for some standard procedures there is a "formula", e.g.:

CLEARANCE ISSUANCE formula (route / departure)

1. Destination

2. Route

3. Initial altitude

4. Cruising level

5. SID (Standard Instrumental Departure, which one among few possibles)

6. Squawk code (transponder code)

7. Departure frequency

Example

(DRY TEXT -> C : ATCO ; P1, 2, 3 ... P-i-Cs)

C D-23GH. Turn left heading 240° direct ROSCA. Climb FL130.

P1 Turn left heading 240° direct ROSCA. Climbing FL130. D-23GH.

C Estrella 525 heavy. Climb FL170. Pass SAAMI FL140 or higher.

P2 Climbing FL170. To be SAAMI FL140 or higher. Estrella 525 heavy.

P3 Previair 234. Good evening. DIAMA 28, FL140. PARAL 35.

C Previair 234. Good evening. Descend and maintain FL100. Squawk 3312.

P3 Descend and maintain FL100. Squawk 3312. Previair 234.

C Rabbit 487. Climb FL170. Reach SAAMI FL150 or higher.

P4 Climbing FL170. Reach SAAMI FL150 or higher. Rabbit 487.

P1 Cuiba approach, D-23GH. Level at FL110. Request immediate descent.

C D-23GH. Say reason for descent.

P1 We’re picking up rime ice. We’ve got a nose down pitch due stuck elevator. D-23GH.

C D-23GH. Roger. Descend FL70.

P1 FL70. D-23GH.

P5 DIAMA31, FL140. PARAL 38, A6-TYC.

C A6-TYC. Descend and maintain FL120. Squawk 1423.

P5 Descend and maintain FL120. Squawk 1423. A6-TYC.

P4 Cuiba approach. Rabbit 487. We’re experiencing severe chop due vortex from the heavy.

C Rabbit 487. Vectors for avoidance. Turn left heading 240°.

P4 Turn left heading 240°. Rabbit 487.

P6 Cuiba control. Cityair 687. Good evening. Passing altitude 4,000 ft.

C Cityair 687. Good evening. Climb and maintain FL70! Squawk 2254!

P6 Cityair 687. Climbing FL70. Squawk 2254.

P5 MAYDAY MAYDAY MAYDAY, Cuiba control. A6-TYC. Cessna Citation, 9 miles DME north-east PARAL, FL100. Two crew, two passengers. The captain is not well at all. Suspected stroke. Request immediate diversion to Tocaran International.

C A6-TYC. Roger MAYDAY. Stand by.

C Previair 234. Aircraft behind you requires priority handling. Hold at PARAL FL100. Expect onward clearance at time 39.

P3 Hold at PARAL FL100. Previair 234.

C A6-TYC. Continue direct PARAL. Cleared PARAL 1 alpha arrival Tocaran runway 34L. Descend and maintain altitude 6,000 feet, QNH 1007.

P5 Continue direct PARAL. Cleared PARAL 1 alpha arrival runway 34L. Descend and maintain altitude 6,000 feet, QNH 1007. A6-TYC.

P7 CMF287. FL170.

C CMF287. Contact Porto Centre 128.750.

P7 Contact 128.750. Good bye. CMF287.

C D-23GH. 12 miles south-east SAAMI, FL70. What is your situation now.

P1 We’ve regained full control of the aircraft. May we maintain this level. D-23GH.

C D-23GH. Affirm. Continue direct ROSCA FL70.

P1 Continue direct ROSCA FL70. D-23GH.

C Rabbit 487. Turn right heading 300°.

P4 Right heading 300°. Rabbit 487.

C A6-TYC. An ambulance will meet you on the south apron for a rapid transfer to hospital. Descend altitude 3,000 ft. Contact Tocaran tower on 124.450.

P5 Descend altitude 3,000 ft. Contact 124.450. Thank you. A6-TYC.

C Previair 234. Cleared PARAL 1 alpha arrival runway 34L. Descend and maintain altitude 6,000 ft, QNH 1007. Prevair 243.

P3 Cleared PARAL 1 alpha arrival runway 34L. Descend and maintain altitude 6,000 ft, QNH 1007. Prevair 234.

P2 Cuiba approach. Estrella 525. Level at FL170. We have loss of cabin pressure which we believe is from the right hand forward service door. Request lower.

C Estrella 525. Roger. Descend FL130.

P2 Descend FL130. Estrella 525.

INTERPRETATION and EXPLANATION in simple ENGLISH

(Note : Every "!" mark denotes explicit request for compliance with given order, and "?" mark denotes logical question, emphasized by grammar rules)

C Delta-2-3-Golf-Hotel (, do you copy) ?, Turn left (in) heading 2-4-0° direct ROSCA ! (and) Climb Flight Level 1-3-0 !

P1 (During) Turn left heading 2-4-0° direct ROSCA, (In) climbing (to) Flight Level 1-3-0, Delta-2-3-Golf-Hotel.

C Estrella 5-2-5 heavy (, do you copy) ?, Climb (to) Flight Level 1-7-0 ! Pass SAAMI Flight Level 1-4-0 or higher !

P2 Climbing (to) Flight Level 1-7-0, to be SAAMI (at) Flight Level 1-4-0 or higher, Estrella 5-2-5 heavy.

P3 Previair 2-3-4 (Control, do you copy ?), Good evening; DIAMA 2-8, Flight Level 1-4-0, PARAL 3-5.

C Previair 2-3-4 (, do you copy ?) Good evening; Descend and maintain Flight Level 1-0-0 ! (Set your) Squawk (to) 3-3-1-2 !

P3 (Confirmig that we are in) Descend and maintain Flight Level 1-0-0, (And to) squawk 3-3-1-2, Previair 2-3-4.

C Rabbit 4-8-7 (, do you copy)?, Climb (to) Flight Level 1-7-0 ! Reach SAAMI Flight Level 1-5-0 or higher !

P4 Climbing (to) Flight Level 1-7-0, (To) reach SAAMI Flight Level 1-5-0 or higher, Rabbit 4-8-7.

P1 Cuiba approach, (Control, do you copy)?, Delta-2-3-Golf-Hotel ; (In) level at Flight Level 1-1-0, (Can we) request immediate descent ?

C Delta-2-3-Golf-Hotel (, do you copy) ? Say reason for descent !

P1 We’re picking up rime ice, We’ve got a nose down pitch due stuck elevator, Delta-2-3-Golf-Hotel.

C Delta-2-3-Golf-Hotel (, do you copy)? Roger ! Descend Flight Level 7-0 !

P1 (In) Flight Level 7-0, Delta-2-3-Golf-Hotel.

P5 DIAMA 3-1, Flight Level 1-4-0, PARAL 3-8, Alpha-6-Tango-Yenkee-Charlie.

C Alpha-6-Tango-Yenkee-Charlie (, do you copy)? Descend and maintain Flight Level 1-2-0 ! (Set your) Squawk (to) 1-4-2-3 !

P5 (Confirming to) descend and maintain Flight Level 1-2-0, Squawk (set to) 1-4-2-3, Alpha-6-Tango-Yenkee-Charlie.

P4 Cuiba approach (Control, do you copy ?), Rabbit 4-8-7; We’re experiencing severe chop due vortex from the (previous) heavy (aircraft).

C Rabbit 4-8-7 (, do you copy) ?, (Use) vectors for avoidance ! Turn left, (to) heading 2-4-0° !

P4 (In) Turn left, (to) heading 2-4-0°, Rabbit 4-8-7.

P6 Cuiba control, (do you copy ?), Cityair 6-8-7; Good evening, Passing altitude 4000 feet.

C Cityair 6-8-7 (, do you copy)? Good evening; Climb and maintain Flight Level 7-0 ! (Set your) Squawk (to) 2-2-5-4 !

P6 Cityair 6-8-7 (Control, do you copy) ?, Climbing (to) Flight Level 7-0. Squawk (set to) 2-2-5-4.

P5 MAYDAY MAYDAY MAYDAY, Cuiba control, (do you copy ?), Alpha-6-Tango-Yenkee-Charlie ; Cessna Citation, 9 miles DME north-east PARAL, Flight Level 1-0-0; Two crew, two passengers; The captain is not well at all, Suspected stroke, (Can we) Request immediate diversion to Tocaran International !?

C Alpha-6-Tango-Yenkee-Charlie (, do you copy)? Roger MAYDAY ! Stand by !

C Previair 2-3-4. Aircraft behind you requires priority handling ! Hold at PARAL (at) Flight Level 1-0-0 ! Expect onward clearance at time 39 !

P3 (We shall be in) hold at PARAL (at) Flight Level 1-0-0, Previair 2-3-4.

C Alpha-6-Tango-Yenkee-Charlie (, do you copy)? Continue direct (to) PARAL ! Cleared PARAL 1 alpha arrival, Tocaran runway 3-4 Left ! Descend and maintain altitude 6000 feet, (Accept official) QNH (as) 1-0-0-7 (hPa) !

P5 (We shall provide in) Continue direct (to) PARAL, (After Previous, we shall have) Cleared PARAL 1 alpha arrival runway 34L, (and) Descend and maintain altitude 6000 feet, (Accepted) QNH 1-0-0-7 (hPa), Alpha-6-Tango-Yenkee-Charlie.

P7 Charlie-Mikey-Foxtrot-2-8-7 (Control, do you copy) ? ; (We are at) Flight Level 1-7-0.

C Charlie-Mikey-Foxtrot-2-8-7 (, do you copy) ? Contact Porto Centre (at) 1-2-8decimal7-5-0 (MHz) !

P7 (We shall) contact (at) 1-2-8decimal7-5-0 (MHz); Good bye, Charlie-Mikey-Foxtrot-2-8-7.

C Delta-2-3-Golf-Hotel(, do you copy)? ; (You have to be) 1–2 miles south-east SAAMI, (at) Flight Level 7-0 ! What is your situation now !?

P1 We’ve regained full control of the aircraft; May we maintain this level ? Delta-2-3-Golf-Hotel.

C Delta-2-3-Golf-Hotel (, do you copy)? Affirm(ed) ! Continue direct (to) ROSCA (at) Flight Level 7-0 !

P1 (We shall) continue direct (to) ROSCA (at) Flight Level 7-0, Delta-2-3-Golf-Hotel.

C Rabbit 4-8-7(, do you copy)? Turn right, (to) heading 3-0-0° !

P4 (We shall turn to) Right, heading 3-0-0°, Rabbit 4-8-7.

C Alpha-6-Tango-Yenkee-Charlie (, do you copy)? An ambulance will meet you on the south apron for a rapid transfer to hospital! Descend (to) altitude 3000 feet! Contact Tocaran Tower (Air Traffic Control) on 1-2-4decimal4-5-0 (MHz)!

P5 (To) descend (to) altitude 3000 feet; (To) contact 1-2-4decimal4-5-0 (MHz), Thank you, Alpha-6-Tango-Yenkee-Charlie.

C Previair 2-3-4 (, do you copy)? (You are) cleared (for) PARAL 1 alpha arrival, runway 3-4 Left! Descend and maintain altitude 6000 feet, (Set altimeter as) QNH 1-0-0-7(hPa)! (AND READ BACK,) Prevair 2-4-3!

P3 (In) Cleared (as) PARAL 1 alpha arrival, runway 3-4 Left, (To) descend and maintain altitude 6000 feet, (Have set altimeter to) QNH 1-0-0-7(hPa), Prevair 2-3-4.

P2 Cuiba approach (Control, do you copy ?), Estrella 5-2-5; (We have) level(ed) at Flight Level 1-7-0, we have loss of cabin pressure which we believe is from the right hand forward service door; (Can we) Request lower (flight level)?

C Estrella 5-2-5 (do you copy) ? Roger ! Descend (to) Flight Level 1-3-0 !

P2 (To) descend (to) Flight Level 1-3-0, Estrella 5-2-5.

References

Semantic and operational strategy, scope and rules

Example

See also

References