Airbus is helping make the skies more efficient and reduce the aviation sector’s environmental footprint through its participation in developing the initial 4D (i4D) concept for a more connected airspace. 
This is a key part of Europe’s SESAR (Single European Sky ATM Research) joint undertaking, with Airbus taking an active role in industry partnerships that are focused on developing breakthrough technology for trajectory-based air traffic management (ATM) operations via real-time information exchange between aircraft and controllers. 
“We believe in the potential for more efficient aircraft operations and arrival sequences with the i4D concept, which has become a key focal point in Airbus’ involvement with SESAR,” said Jérôme Condis, Airbus Engineering Data Link and FMS Manager. 
Condis added that Airbus is in an important position to help lead advances in air traffic management by leveraging its expertise as an aircraft manufacturer that pioneers technological breakthroughs, and its reputation as a world leader, to encourage industry stakeholders on the way forward. 
Taking the next steps forward in research 
Research and development for i4D is taking a major step forward this year – transitioning from smaller projects to demonstrate technical feasibility and benefits to a wider scope that will include initial deployment in real revenue flight conditions through 2022. 
“So far, we have supported the evaluation of the Extended Project Profile (EPP) – which is a key technological brick in i4D as the link that provides aircraft trajectory information from the air to the ground using ‘ADS-C’ (Automatic Dependent Surveillance-Contract),” said Jean-Louis Bigot, Airbus ATM Engineering, SESAR Demonstration Project Coordinator. “Now, the goal is to integrate the EPP trajectory information into the larger air traffic management system to allow controllers to sequence traffic at a given waypoint.” 
With the i4D concept, aircraft would be able to automatically adapt their speed and trajectory in-flight to arrive at a given position at the appropriate time – meaning, for example, aircraft holding time around an airport to wait for a landing slot could be significantly reduced or eliminated. 
“This would be a huge revolution in the way air traffic is managed,” Condis explained. “It would help fulfill major targets of SESAR by reducing fuel burn and the aviation sector’s environmental footprint through optimized traffic sequencing, improved arrival/departure management and increased airspace capacity, while also further enhancing safety.” 
DIGITS: it all adds up
The initial deployment of the i4D concept in airline conditions is part of the DIGITS (Demonstration of ATM Improvements Generated by Initial Trajectory Sharing) project within the scope of SESAR 2020 – the second wave of research projects based on the results from the initial SESAR 1 phase. 
From 2016-2019, the DIGITS consortium is focused on establishing and certifying the appropriate ground infrastructure to integrate the EPP information in air traffic controller operations. In late 2018, the project aims to start equipping commercial airliners for the real-time exchange of EPP data, with the goal of fitting approximately 100 aircraft by end of 2019. 
“We’re going a step further than what already has been done – taking our advancements to the real world!” Bigot said. “We are being very proactive to develop solutions for the future!” 
DIGITS brings together a range of industry stakeholders, from aircraft manufacturers to air traffic controllers, air navigation service providers, equipment manufacturers and airlines. Among the SESAR 1 projects that it builds on is PEGASE (Providing Effective Ground & Air data Sharing via Extended Projected Profile) – in which Airbus conducted some 60 test flights to support the initial evaluation of the EPP system.