July 17, 2020

As “tip-to-tail” aircraft connectivity technology continues to mature, choosing solutions that meet safety, compliance, financial and passenger demands has become more complex.

Understanding the aircraft’s three unique connectivity domains, as recognized by the International Civil Aviation Organization (ICAO), can help decision-makers better evaluate their options. A full breakdown of these domains is featured in the latest NBAA GO Maintenance Conference session, Connectivity Tip-to-Tail, which will be held on Monday, July 20. The session will also explore the future of connectivity, from advanced onboard systems to the European Space Agency’s “Iris” air traffic management program.

Beginning with the cockpit, the Aircraft Control Domain (ACD) is the most operationally critical domain – and the most strictly regulated with regard to redundancy and all-weather connection stability requirements. This domain supports cockpit safety and aeronautical operational control, including communication, navigation and surveillance needs, such as ADS-B and controller-pilot data link communications (CPDLC) systems.

“The ACD needs high reliability,” said presenter Bill Rowell, technical sales manager with Inmarsat. “We want to ensure that the pilots and controllers on the ground have a robust connectivity link during all stages of the flight.”

All ACD connections must perform at ICAO Global Operational Data Link Document (GOLD) standards, but do not require as much bandwidth capacity – a less sophisticated L-band frequency. This offers data throughputs ranging from 2.4 kilobytes per second (kbps) to 432 kbps, which will typically suffice.

Cockpit, Systems and Passenger Domains

Maintenance and operational efficiency can be enhanced through the Airline Information Services Domain (AISD), which hosts non-mission-critical functions kept separate from passenger-accessed networks.

Though the least critical in terms of meeting regulatory standards and passenger communication needs, AISD connections can make a significant financial difference in the operation of the aircraft. Connectivity in this domain enables advanced tracking, such as aircraft health monitoring and predictive maintenance that enables faster, more efficient coordination with an MRO.

While an L-Band connection can support some AISD functions, such as an electronic flight bag, Rowell noted that advanced engine and airframe data collection and transmission will likely require air-to-ground systems, or more advanced satcom connections using Ku-band, which has 1-12 megabytes per second (mbps) throughput, or Ka-band, with 1-33 mbps throughput.

Principals will likely be most concerned with the Passenger Entertainment and Network Services Domain (PIESD), which provides connectivity for passenger needs, such as web browsing, video streaming and inflight communications.

Driven by a large increase in onboard devices – a Satcom Direct study shows that today’s business jet passengers will on average carry at least one smartphone, one PC and one tablet – PIESD communications have been the driving factor behind the growth of Ku- and Ka-band systems, which best support this domain’s substantial broadband needs.

For more information on these domains, including purchasing considerations related to cybersecurity and expanded functionality, watch the Connectivity Tip-to-Tail session and join the live Q&A at 3 p.m. (EDT) on Monday, July 20.