Editor's Note: Synthetic Vision: Time for Standards

Synthetic vision (SV), the database-driven presentation of terrain outside the cockpit, is gaining momentum. Avionics magazine has described development work by Rockwell Collins, Honeywell, BAE Systems (with partner Nav3D) and Boeing. We have covered Chelton and Universal Avionics, both of whom have received FAA certification for general aviation (GA) products. Military and business aviation are the next big opportunities.

Synthetic vision technology clearly could enhance flight safety, as air traffic densities increase. Many questions must be answered, including how to monitor database integrity in real time. But the "all-weather" technology promises to pay its freight by increasing pilot situational awareness, particularly in the initial approach and missed approach phases of flight.

Bizjet original equipment manufacturers (OEMs) have adopted or are adopting infrared (IR) capability (known as enhanced vision) on head-up displays. And their customers are now permitted to reap limited operational benefits. The next step may be to combine SV and IR technologies, head-down. Kollsman recently exhibited an enhanced/synthetic vision system (ESViS) prototype at the National Business Aviation Association show. The company aims to introduce a product in 2007. The time is coming for synthetic vision, enhanced/synthetic vision, and further enhancement of IR-based systems.

BAE Systems sees an opportunity for its millimeter-wave (MMW) radar to complement existing IR systems. The company has developed a method to fuse IR and MMW radar inputs on the head-up display, while presenting synthetic information on a head-down display. It recently demonstrated this, using an SV component by Nav3D, as part of a NASA program. The combination of IR and MMW--with its ability to see through fog--could increase the probability that business aircraft pilots can descend safely to 100 feet above ground level before seeing the runway or approach lights unaided, as FAA now permits them to do. MMW has issues such as antenna size, but promises value.

BAE foresees SV elements entering the corporate market in the next four to five years, a sentiment echoed by Collins. Honeywell anticipates new entrants in the next two to three years. It stresses SV's boost to situational awareness. Synthetic portrayal of terrain on a primary flight display (PFD)--as Honeywell has shown in concept form--using its time-tested enhanced ground proximity warning system (EGPWS) database, could ease workload by allowing information to be more easily integrated by the pilot. Pilots learn to fly visually and spend 80 to 90 percent of their time flying in visual conditions. SV retains those cues, making it seem natural to fly. (Honeywell is looking at real-time sensors, too.)

Kollsman is also bullish on its planned ESViS product, the current version of which insets and registers an infrared image with a surrounding synthetic image on the PFD. This double presentation allows pilots to compare the two images and spot obstacles on the runway.

Clearly, all this investment anticipates demand, if not now, then in the not too distant future. FAA needs to move ahead to develop guidance for designers of Part 25 avionics in order to avoid case-by-case certifications of technology now in the pipeline. Guidance is "way past due," complains an observer at a major avionics firm. This is not to say FAA is standing still. It has put out a draft advisory circular regarding synthetic vision for Part 23 airplanes.

Developers expect FAA will request RTCA to form a special committee some time this year. Industry experts are volunteering to co-chair this panel, which will craft a consensus-based, minimum operational performance standard (MOPS) that should form a basis for regulatory guidance--a technical standard order (TSO). FAA has expressed interest in doing this. The agency, with NASA's assistance, is preparing to finalize its requirements and may widen the scope to include enhanced vision, too. Let's hope FAA moves ahead with all due speed. The alternative would be for it to work with manufacturers one by one, an expensive and inefficient process fraught with risk.