An emerging AI-based technology for flight simulators offers a virtual traffic environment and fully automated synthetic ATC services, enabling a flight crew training experience that is significantly closer to real-world operations, reports Aimée Turner.

Simulated Air Traffic Control Environment, or ‘SATCE’, automates ATC to the point where its champions claim that combining SATCE with an out-the-window visual system and weather simulation ‘completes’ the synthetic environment. Equally applicable to military and civil, fixed-wing and rotary-wing pilot training, SATCE also provides flight crews with far more realistic workloads in scenario-based training as instructors are freed from having to play the role of controller and consequently have more time to observe.

As SATCE supports the adoption of real-time scenario-based training, it is well placed to enhance competency-based training approaches and programmes such as the Multi-crew Pilot Licence (MPL) and evidence-based training traffic simulation, and ease into use new Air Traffic Management (ATM) procedures associated with the FAA’s NextGen and the EU’s SESAR programme as well as new aircraft technologies such as ADSB-IN and Data Link communications. 

While SATCE is not yet required for flight simulation training devices, except by the European Union Aviation Safety Agency for one particular licence, organisations across the global flight training industry are starting to integrate SATCE into their pilot training programmes and flight training devices.

Dr Jeremy Goodman believes that once widely established and proven in training, SATCE will become an essential mandatory component of synthetic flight training programmes. “SATCE will likely be adopted and in use with several training providers by the end of this year,” he tells CAT. Goodman is the SATCE product lead for Quadrant Group. He is also the industry editor for the Flight Simulator Engineering and Maintenance Committee (FSEMC) Working Group on SATCE that has published ARINC Specification 439A and has helped lead Quadrant’s development of a fully automated, dynamic and interactive SATCE solution. 

“The pandemic has served to highlight the case for using SATCE in flight training and in terms of ‘bang for buck’, SATCE delivers a lot of training value and efficiency for the investment. We think it’s the next obvious big jump in simulation fidelity,” Goodman noted.

He points to several reports, including an analysis of voluntary submissions to NASA's Aviation Safety Reporting System (ASRS) by Embry-Riddle Aeronautical University, which showed a sharp 1000% increase in the number of incident reports filed by pilots which had a proficiency-related Covid-19 aspect, highlighting the unintended consequences of long periods of absence and lack of recent operational exposure. “That gap between current simulator experience and real-world operations is particularly obvious concerning the synthetic environment outside the cockpit which is missing complexity without other traffic and realistic ATC. It may never be possible to create a simulation that fully matches real-world complexity, but SATCE serves to further close the gap,” says Goodman.

“Current deficits in the simulation fidelity reduce the ability of regular and refresher flight training to fully prepare pilots for a return to work after a period of not flying,” he says. “SATCE delivers valuable exposure to more realistic operations in the simulator that enhances preparedness. The logic is that higher simulator fidelity incorporating SATCE results in more realistic workloads, greater familiarity with operational procedures, and enhanced training transfer. These support the development of pilot core competencies that ultimately contribute to building proficiency and resilience. More proficient and resilient flight crews deliver efficient operations and augment flight safety.”

Quadrant has supported trials of its AI-based SATCE solution, ‘Interact’, on a full-flight simulator and on several fixed-base high-fidelity FTDs involving both ab initio and experienced flight crews. Interact has been integrated on several simulation platforms and with multiple visual systems, with ongoing development and testing involving FlightSafety International in the US and high-fidelity FTD manufacturer MPS in the Netherlands. 

Goodman reports that Quadrant has observed marked benefits during these trials, with interviews after flight crews’ exposure clearly reflecting their enthusiasm. As well as expanding its data to support training at multiple European and North American airports and associated airspace, Quadrant’s recent R&D activity has further involved immersive and 3D gaming technologies, which offer the prospect of exciting new applications. Indeed, Goodman says integrating SATCE with 3D VR environments makes perfect sense as this adds missing traffic and realistic radio and data communications, even arguing that XR-based training tools actually require SATCE, as old ways of simulating ATC using human actors are impossible. 

Communication Muscle Memory

SATCE’s champions also cite the technology’s ability to support the adoption and use of ICAO Standard Phraseology for radio communications and so supports the use of the English language in simulator training for non-native English speakers. Nick Papadopoli believes the value of this is significant. He worked for Adacel as a subject matter expert at a time when the business was the sole developer of a SATCE solution and still works on continually improving all aspects of SATCE operations. A commercial pilot, he understands SATCE from a crucial safety perspective. “I would say that SATCE is primarily a safety enhancer,” Papadopoli says. “The principles of flying are Aviate, Navigate and Communicate, and the communications aspect remains the weakest link in the chain. It is a recurring data point where incident analysis demonstrates that communications invariably stand to be enhanced because in a lot of cases it comes down to a lack of focus on applying standard Aviation English which, if it is not used in the correct way, leaves you wide open to misinterpretation. All too often the holes will line up to create the Swiss cheese model.”

Papadopoli says SATCE is a tool to exercise and practise depending on the level of fidelity in use which means that if the AI component in SATCE is good, practise can happen. “It gives context to training which is crucial. It does not matter how much you practise, your training needs to correlate the input with the most effective response, especially in an emergency situation. The communications ‘muscle memory’ must be developed so it’s not neglected or rushed.”

He insists that flight crew need to be as good as controllers in terms of their high, rigorous standards which are frequently quality tested and recommends that SATCE becomes standard for all early career pilots. “Covid has resulted in a huge number of inexperienced pilots with less operational experience,” he argues, “creating a global workforce that is ‘not entirely versed’ in how to apply their communications training.” This is, in his opinion, a deficiency that is more serious, he says, in non-native speakers. Papadopoli advises airlines to test their early career flight crew with emergency scenarios to find their weakest point but also more experienced crews too, pointing out that “they may have experience in managing the flight but they may have scant experience managing the operation.”

Five Years in the Field

Neil Waterman is ASTi’s Commercial Aviation Director, which has delivered 52 systems across a significant variety of devices. The first ASTi SATCE system, known by the name SERA (Simulated Environment for Realistic ATC), was deployed in November 2017 – so the business today has five years of real use. The first customer was military although second was a global airline using the system on two new Level D FFSs. 

“This experience has been invaluable in allowing us to fully understand the real training requirements for the spectrum of possible use-cases that SATCE ‘fits’, and it turns out SATCE brings ‘value’ at all phases of flight training, from ab initio new pilots through experienced flight crew with thousands of hours in their log book,” says Waterman, who adds that one of his favourite analogies is “flight training without ATC and other traffic is like training for a hurdles race without the hurdles or the lane lines”.

For Waterman, the benefits of SATCE are essentially through providing a framework where all training is conducted according to regional standards as it is better at developing phraseology and offering improved situational awareness. 

He explains how the business started developing the system in 2006 although, because it did not believe it had a viable solution, launched nothing as it did not want the pilot community frustrated to the point of turning off any fielded system. In the early days ASTi integrated third-party text-to-speech and speech-recognition solutions but soon learned early that Aviation English is so highly specific that current solutions are all developed in-house today. “We purposefully did not expose ourselves to the sharp end of the stick until we were fully ready, and I believe we got our timing one hundred percent right in that respect,” he says.

“We feel quite confident that this technology will make a significant impact in pilot training,” Waterman says. “We understand how people want to use these systems. ASTi’s background is in flight simulator sound and communications systems, so we know the perspective from the cockpit. This is unique in the marketplace, as all other potential SATCE suppliers come from an ATC tower training perspective.” He believes this is a critical difference as an ATC tower is, by default, a geographically fixed entity, hence, any technology developed to solve this problem does not have to handle the vast diversity of pilot speech accents and variation of phraseology that a flight simulator will support.

“Consider,” he says, “an airline LOFT scenario which may start with the aircraft departing from a city in Europe under EASA flight rules and phraseology, and arriving into a city in the USA, with FAA standard terminology, crewed by a crew from Asia, for example. The next use of that same simulator may be completely different, with new MPL students practising takeoffs and landings at an airport in Japan.”

 Asti SATCE Simthetiq.jpg

ASTi’s Simulated Air Traffic Control Environment (SATCE) product has been integrated with Simthetiq’s image generator, library of airports and 3D simulation entity models. Image credit: Simthetiq.

Embry-Riddle Aeronautical University has deployed multiple SERA systems as part of a new initiative for its pilot training programme, and its independent research results has shown an overall reduction of time to solo flight of better than 30% for the autumn 2021 student intake. This was a significant piece of research since this was the first important hard data showing the benefits of using SATCE. “The cost saving in terms of equivalent time saved plus the reduction in necessary remedial training is a validation of the industry’s effort to develop SATCE,” Waterman says.

He adds the business has worked with 15 or so flight simulator manufacturers and believes that the key to the future of SATCE is to allow them to get their hands on a system to actually try it out. “That’s when they press the green light,” he says. In terms, however, of the future uptake of SATCE, Waterman believes it is likely to be spearheaded by new training providers who will be the future innovators as SATCE is essentially ‘invasive’ to existing training programmes. 

“The issue here,” he says, “is that creating a training programme in itself is work, so it takes quite some effort to rework an existing programme to use a new capability like SATCE. A new training provider doesn’t have that baggage and can innovate, using SATCE from the very earliest elements of the programme.” He says this may include elements before a new student sees a flight simulator, such as the ASTi Pilot Phraseology Trainer (Pilot PT) Aviation English training tool, which uses the same core speech recognition and text-to-speech technologies from the ASTi SERA product to allow a novice pilot to learn how to speak like a pilot, using an interactive web-based application.

While SATCE is appropriate for both civil and military flight training, it is arguably most applicable in military flight training for transport category aircraft flight crews who operate increasing hours in civil airspace, as well as for disaster-relief type operations offering not only efficiency savings but also a reduction in environmental impact. The British RAF is also known to be conducting a rigorous SATCE evaluation programme with its pilots exposed to one of two streams – one with SATCE, and one without – to figure out where the main benefits lie.

UFA, a US business specialising in ATC simulation products and voice-recognition technologies, has developed the ATWorld simulation solution, a FSTD plug-in providing an automated, realistic and contextually correct ATC environment, simulating traffic operating in and around the airport, airborne and ground. ATWorld has been integrated successfully with the T-1A Jayhawk aircraft, E-3 AWACS and C-17 flight simulators. UFA president Larry Pennett tells CAT the reason for this interest from military trainers: “We observed that military organisations showed increased interest in SATCE to provide pseudo-realistic training operating in a congested airport environment similar to major civilian airports since military pilots’ exposure to this environment is limited.”


Industry standards describing SATCE can now be considered mature with the publication in August 2020 of ARINC Specification 439B, which marked the culmination of years of industry-wide collaboration involving a wide range of stakeholders, including the FAA. The technical requirements for a SATCE system detailed in ARINC 439B have now been harmonised and outlined in ICAO guidance (ICAO Doc 9625) and EASA draft certification specifications for training devices (NPA 2020-15).

Quadrant’s Goodman believes SATCE is “in the wings” since it has been defined but not yet mandated by international regulators. Indeed, EASA has included SATCE as part of the environment simulation in proposed future FSTD specifications in NPA 2020-15 where SATCE is part of an FSTD ‘capability signature’ (FCS). Goodman also notes further developments stateside: “Although not yet incorporated into FAA qualification standards, the FAA plans to test and to evaluate SATCE in one of its research simulators with follow-on guidance for its possible use in flight training.”

ASTi’s Waterman is confident that within a decade every flight simulation system will have SATCE. Globally, there are at least three specialist suppliers offering mature SATCE solutions, all of which are outside the major training device manufacturers. However, Goodman reports that sim manufacturers are watching the technology with interest, especially as customer requests for SATCE have been increasing recently and new applications for using SATCE are emerging. 

“SATCE technology has massive potential,” Goodman says, “and once it is adopted and delivering obvious benefits there will be no going back.” Why? He says it is hard for instructors and flight crews to go back to training at a sterile airport, empty airspace and with a silent radio once they’ve experienced a full environment simulation. “As SATCE is progressively adopted, we expect it will become an industry standard and all the major training device manufacturers will begin to offer it. They will either form partnerships with vendors or secure the technology via acquisition. We don’t expect there will be the appetite to develop SATCE themselves, however, as it takes time and considerable investment.”