Miscommunication errors can be prevented

by Christopher Rieken, Director, Operational Safety, NAV CANADA and Anthony McKay, Vice President and Chief Safety and Quality Officer, NAV CANADA

Aviation safety, in the air and on the ground, is a shared responsibility between all aviation stakeholders. Communications are essential to safety, and safety investigations often cite communications as a primary contributing factor in safety events. It is easy to forget that the voice on the other end of the radio is a person, too. If everyone begins with the same foundation of standard phraseology, there is less room for error or misinterpretation.

Miscommunications can happen between even the most experienced professionals. Increasing awareness of some of the potential miscommunication errors identified as contributing hazards in safety events may prevent them from reoccurring. Some of these opportunities for miscommunication can be mitigated by using standard phraseology and communications, including:

• Flight plans or NOTAMs being filed using incorrect local time rather than Zulu/UTC

  All of aviation, including air traffic services (ATS) staff and their systems, use Zulu/UTC as the primary time datum. When filing a flight plan, submitting a NOTAM or advising ATS of planned aviation activity, Zulu/UTC shall be used to avoid misfiling and activation of a flight plan or NOTAM or negating alerting services for a flight.

• Flight plans or NOTAMs being filed using spoken letters from the alphabet or the airport name rather than using phonetics from the airport ident Figure 1

  Was that Sidney or Sydney? Over the phone or VHF, C-Y-Q-Y sounds a lot like C-Y-Q-I. charlie – yankee – quebec – yankee is very clear. Do it right the first time, and “slow down to go faster” so that if something goes wrong, Search and Rescue is looking for you around Sydney instead of the miscommunicated Yarmouth.

• Readback/hearback errors

  While not all air traffic control (ATC) clearances and instructions require a pilot to readback the instruction, it is easy for a pilot or ATS to hear what they expect to hear. Miscommunication risk is increased on busier frequencies, when ATS or pilots speak too fast or when vigilance is reduced due to complacency when operating in a familiar or routine operation.

• Similar sounding call signs

  Aircraft civil registrations or commercial air operator call signs can often sound similar. Identical letters or numbers at the beginning or the end of a call sign and call sign “anagrams” can lead to a pilot mistakenly responding to or actioning a clearance from ATS intended for another aircraft. The risk of miscommunication can be increased by abbreviating a callsign in a readback or by grouping numbers. ATS will endeavour to inform pilots when similar sounding call signs may be on the same frequency to raise awareness and attention. It is imperative that civil idents use phonetics for the full registration and that call signs use the correct and full aircraft call sign prior to the number.

Figure 1 - Text version

A – Alpha
B – Bravo
C – Charlie
D – Delta
E – Echo
F– Foxtrot
G – Golf
I – India
J – Juliet
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

Z – Zero
1 – Wun (One)
2 – Two
3 – Tree (Three)
4 – Fower (Four)
5 – Five
6 – Six
7 – Seven
8 – Alt (Eight)
9 – Niner (Nine)

NAV CANADA has worked extensively with flight training units, commercial aviation leaders and aviation councils to develop several Operational Guides and reference materials for critical areas of communication, such as instrument flight rules (IFR), visual flight rules (VFR) and ground traffic phraseology, NOTAMs, flight planning, and Aviation Weather Services. These guides are learning tools and reference documents supporting standardized communications between pilots, ATS and other aviation stakeholders. The guides are on the NAV CANADA website at NAVCANADA.CA—Operational Guides.