Professional Pilot, May 2017

CPDLC is a tool to mitigate misunderstandings and language issues Controller Pilot Data Link Communications CPDLC is a digital means of exchanging messages sending requests and receiving instructions between pilots and ATC An everyday comparison is sending text messages via a mobile phone CPDLC is one component of the Future Air Navigation System FANS that traces its roots back to a report published in 1988 FANS was conceived because projections at the time indicated a rapidly escalating demand for air travel and accordingly the need for increased airspace capacity Manufacturers of transport category aircraft realized where the future was headed and introduced their own proprietary products in anticipation of demand The same technology was marketed under slightly different names The Boeing product was FANS 1 and Airbus called theirs FANS A The term FANS 1 A is now used as a universal descriptor for aircraft with specific and similar characteristics regardless of whether the airframe is an airliner or a business jet Peak performance occurs with FANS 1 A which incorporates a few upgrades to 1 A Premium installations combine ADS C and satellite based CPDLC One is possible without the other However beginning in 2020 the combination will be required to fly in the North Atlantic Track 92 PROFESSIONAL PILOT May 2017 High Level Airspace now called NAT HLA but formerly known as MNPS above FL290 Having ADS C and CPDLC in concert serves 2 functional purposes 1 automatic position reporting without resorting to a congested HF radio frequency and 2 unambiguous communication with ATC because of preprogrammed messages embedded within the CPDLC software The safety benefit of CPDLC is that it reduces or eliminates communication errors associated with language Josh Shields a corporate pilot based near Washington DC is a proponent of CPDLC and has used it in both the Global Express and Falcon 900 He believes its an important tool when flying through airspace worked by controllers with thick accents or poor quality transmitters like in parts of India Pakistan or Russia Shields points out that CPDLC is especially beneficial during reroutes One challenge of flying internationally is dealing with unfamiliar intersections The situation is exacerbated when controllers pronounce the letters that make up an intersection or fix in their native language instead of English When a clearance is received via CPDLC in lieu of voice the new route can be electronically transferred directly into the flight management system Using this technique reduces the chances of confusion Good CRM dictates the crew verifies the new points on the flight plan but its much easier to do so when looking at a written version If a crew wants to climb or descend or needs a lateral deviation for weather they can request it using the canned or standard phrases embedded in the CPDLC interface The controller who may or may not be operating at a high level of English proficiency then sees a standard ICAO request which is easier to understand CPDLC does provide a means to send free text messages between the aircraft and the ground but the practice is highly discouraged Much like voice communications once one deviates from the standard scripted exchange the likelihood of misunderstandings increases The irony is that ICAO recommends that AE training described in the proficiency matrix not be focused exclusively on standard phraseology at the expense of learning plain English Because of the time required to complete a CPDLC exchange the system is not used in the terminal environment which means that controllers must revert to voice The goal of the ICAO mandate is that standard phraseology be used as much as possible but also that non native English speakers have the ability to deviate from AE by asking questions and responding to inquiries in an appropriate manner Conclusion practice good radio techniques Pilots can help ATC by practicing good radio technique and sticking to ICAO recommended practices and terminology when flying internationally Things like the meter the box and the fish finder dont exist in the ICAO glossary used to train controllers Even simple things matter when it comes to being lost in translation like using oh instead of zero for instance Deliberately reducing the rate of spoken speech and focusing on proper annunciation can also be beneficial CPDLC is a great tool with enormous potential but a dose of flight discipline and self awareness also goes a long way in making the system better Requests made through CPDLC are standardized and easier to understand This screen depicts several options to request lateral changes to the flightpath Shannon Forrest is a current line pilot CRM facilitator and aviation safety consultant He has over 10000 hours and holds a degree in behavioral psychology