[Avionics Magazine 04-27-2016] Spectralux Avionics unveiled a new dual stack Future Air Navigation Systems (FANS) 1/A Aeronautical Telecommunication Network (ATN) Link 2000+ Controller to Pilot Data Link Communications (CPDLC) data link box, Envoy, at the 2016 Avionics Maintenance Committee (AMC) / Airline Electronic Engineering Committee (AEEC) Conference. The Redmond, Wash.-based data link solutions provider announced the new hardware, the third generation version of its existing data link line, in response to operational demand for an all-in-one data link solution.
Spectralux Envoy Data Link. Image: Spectralux.
While operators have been using FANS for CPDLC in the oceanic environment for more than two decades, new mandates taking effect in Europe and within the North Atlantic Track System have created a need for more aircraft to become equipped with data link capabilities then ever before. The various mandates, aircraft systems, hardware obsolescence and the current split between continental U.S. FANS and European ATN communication channels have added new levels of complexity to equipping aircraft with this arability to enable operational benefits.
"The ATN CPDLC protocol versus the FANS CPDLC protocol is quite different from one another. From the user's perspective it’s the air traffic services via CPDLC, the message sets are not identical but they are functionally similar between ATN and FANS; that's where the similarity ends. Behind the scenes, the protocol, the message handling, the network access is completely different the communication stacks for each are large complex systems by themselves. So you look at it as two independent separate applications running inside the box, one for ATN and one for FANS. From the avionics developer perspective it is as if you are developing two completely independent products and then just hosting them on this computer," Frank Hummel, director of engineering for Spectralux, told Avionics Magazine.
Targeting entry into service and availability of production units for shipping by the third quarter of 2017, Spectralux plans on featuring three separate avionics modules in the certified version of Envoy. These include a Communications Management Unit (CMU) Controller Display Unit (CDU) and a VHF Data Radio (VDR).
Currently, operators that fly in the United States and Europe need separate boxes on their aircraft to digitally exchange CPDLC messages with Europe's VHF Data Link Mode 2 (VDL Mode 2) infrastructure, and the FANS 1/A Data Comm infrastructure that the FAA
is implementing. Recently, Avionics Magazine interviewed
Universal Avionics on a similar topic: the use of its own data link solution for DCL in the United States, for which the company is going to introduce a software update to include VDL Mode 2 functionality. Spectralux is looking to feature this type of functionality upon entrance into the marketplace with Envoy.
For operators that do equip with Envoy or other products that provide dual stack ATN and FANS 1/A functionality, there will be some training involved on how to use the capability in different airspace.
"Think of a flight crossing the Atlantic and going into Warsaw, so it crosses the Atlantic using the FANS protocol when it gets into the U.K. NATS airspace, it would log off of FANS and the pilot would have to do a manual log on again to ATN CPDLC, then stay logged on to ATN to perform CPDLC functionality in European airspace. So, there is a bit of training requirements by flight crews," Ian Gilbert, avionics consultant for Spectralux, told Avionics Magazine.
"The interaction with the unit is exactly the same, whether he's operating FANS over the North Atlantic or CPDLC over Poland. The only difference is [the pilot] gets a slightly more limited network set when he's over continental Europe than when he's over the North Atlantic; but from an operational point of view it's exactly the same user interface in any airspace," Gilbert said.
Interestingly enough, the dual stack capability is not the only forward-thinking functionality for Envoy. Responding to direct requests from its customers, Spectralux also added a Bluetooth transmitter under the faceplate of the Envoy box to provide operators with the capability to allow the system to interact with Electronic Flight Bags (EFBs) or smart tablets in the cockpit.
"What that means is all the [Aircraft Communications Addressing and Reporting System] ACARS Out-Off-On-In (OOOI) reports, any type of ACARS report carries on in this box as it always had been. It is sent by Bluetooth over to the EFB — we're designing an app for that — when the pilot then takes his iPad [and] walks into the crew room or ops center, the iPad connects to the Wi-Fi and all those ACARS messages are sent. There's no cost to the airline at all, so he has his ACARS functionality; not all of it, because there are some real time aspects of ACARS that we can't do like digital ATIS or real time weather reports, but the routine stuff that your ops center needs or maintenance control needs all that can be done without using an ACARS network," said Gilbert.
Hummel admits that the Bluetooth functionality providing a user with the ability to distribute non-time critical ACARS messages to an iPad is not a complete industry "leap" in capability. However, it could provide a big benefit to operators in terms of data needing to be received, derived or computed as soon as the aircraft lands.
Going forward, Gilbert said Envoy appears to address about 25 percent of aircraft flying between the U.S. and Europe today.