It’s a fact: enhancing pilot vision — especially in adverse weather conditions — can reduce the likelihood of accidents, especially on the runway. Runway safety-related incidents represent the highest number of accidents reported in the 2016 International Civil Aviation Organization (ICAO) Safety Report.
Vision system technologies are addressing safety issues by providing a direct countermeasure — creating visibility for the pilot, and thus, eliminating low-visibility conditions as a key factor in civil aircraft accidents.
The FAA’s latest enhanced flight vision system (EFVS) rule is expected to increase use of this technology, resulting in safer landings in challenging conditions. For the first time, air crews can fly certain IFR approaches all the way to landing instead of relying on “natural vision.” The ruling, which went into effect earlier this year, allows certified aircraft to descend beyond the 100 feet previously permitted to complete their landing using an enhanced vision system.
“The new ruling is going to be a major advancement for aviation in general and business aviation specifically,” said Jeff Hausmann, director of advanced flight deck for Gulfstream, the first business jet manufacturer to certify with the FAA an enhanced vision camera system for flight.
“The rule really sets a precedent. It’s the first time that an electronic means of vision is allowed through the entire approach and landing phase,” added Randy Bailey, flight deck interface technologies lead at NASA’s Langley Research Center. “Now that you have made the admission that natural vision is not required, that opens the avenue for new technologies and new capabilities.”
“This new rule improves the business case for EFVS,” noted Grant Sumpter, manager of sales and business development for Astronics Max-Viz, the Portland, Oregon-based manufacturer of enhanced vision systems (EVS). ”Because EVS can see four to 10 times further in obscurants than natural eyesight, this immediately increases the number of opportunities to land when the aircraft would not have been able to land before.”
Gulfstream executives agreed. “The new FAA rule will open up more available runways on bad weather days for EVS-equipped operators,” said Colin Miller, Gulfstream VP of flight operations. “The new rule allows operators to take credit for their enhanced vision systems and file to airports with worse weather than they could in the past, and it significantly increases the chance of a successful approach and landing in very low-visibility conditions.”
NASA’s Pioneering Role
A leader in creating the first synthetic vision systems back in 1999, NASA began to research ways synthetic and enhanced vision could reduce the number of loss-of-control accidents and improve operations through better vision capacity within U.S. airspace.
“We’ve been doing research continually since then, but we are actually getting out of part of the vision system business because the
technology has matured to the point that it can transition” to the commercial sector, said Bailey. “Systems have improved above and beyond what is out there in natural vision, whether it be clouds or other kinds of obscurants. The sensors and the computing systems tied with those sensors are much, much better, as are the displays.”
Bailey said NASA’s role increasingly is that of technology caretaker — ensuring technology transitions successfully, working with rule-making committees and industry work groups to write standards for EFVS operations.
Business Jets Lead EFVS Market Penetration
Gulfstream, an early partner with NASA on enhanced vision systems, has used EFVS systems for at least a decade, with the technology now standard on its large cabin fleet, including its G450, G550 and G650, and an option on the company’s mid-range aircraft.
“A good indicator of our customers’ interest in this technology is the take rate on our optional EVS offering for our mid-cabin — the G280 — which is a remarkable 83%,” said Miller.
Gulfstream is rolling out EVS-3, its next-generation infrared camera to the G500 and G600. It will offer improved resolution over the company’s current system, EVS-2.
“One of our top-level design goals is to continually improve airport access for our customers so they can take off from the airport they choose and land at the airport they choose, when they want to travel,” said Miller. “With this new rule and EVS equipment, you can do that to a large extent regardless of weather.”
FedEx also has adopted EFVS technology as a standard feature on its wide bodies. With over 650 aircraft, FedEx has the largest all-cargo fleet in the industry.
Dan Allen, FedEx Express managing director of flight technology regulatory compliance, said the company is already applying for new EFVS authorization. He noted the rule “would allow us to better serve our customers in all-weather conditions,” particularly on CAT 1 instrument landing system or RNAV (GPS) approaches.
The technology has made FedEx a safer operation, providing the flight crews with better awareness of the terrain and the situation of their flight path control, added Bailey, who said there is now potential for EFVS to move to the commercial airline, rotary-wing and general aviation markets as systems become more affordable.
Industry Eyes Scalability
“It’s a question of scale, so once economies of scale start happening, the price really starts to come down,” said Bailey.
Astronics Max-Viz has more than 2,500 EVS systems installed in the aviation sector, split 60/40 between fixed-wing and helicopters. “Only business and general aviation aircraft have installed the systems to date, but the company has its eye on commercial aviation as it continues to drown the cost of ownership for EVS,” Sumpter said, noting that his firm’s basic FAA-certificated system starts at $9,000. Similar systems, not certificated, are available for the experimental and home-built marketplace starting at $6,000, he added.
Sumpter said Max-Viz is planning several enhancements for its next-generation vision systems. These include introducing high-resolution infrared and visible light sensors that can be used on very large displays; adding more sensors/emitters blended with IR/visible sensors to penetrate obscurants like thick fog and clouds, and integrating synthetic vision systems to provide real-time correction of the GPS position and detection of transient or missing items in the SVS database, such as encroaching aircraft or wildlife on the runway.
“Max-Viz continues to adopt new techniques and technologies to lower the overall cost of equipment/installation and improve the quality of the picture presented,” said Sumpter, noting that the end goal is for the technology to be cost-effective, reliable and compact enough for widespread aviation adoption.
One of many operators watching EFVS developments closely is Air Methods, an air medical transport provider with more than 450 helicopters and fixed-wing aircraft in its fleet.
“Visibility is critical for all helicopter air medical operations,” said Air Methods Leo Morrissette, SVP of aviation operations. “This has led to major investments in safety technologies, systems and training. In 2013, we became 100% night-vision goggle compliant.”
Morrissette said his company is continually staying on top of technology, providing input when appropriate, including to manufacturers to support the company’s procedures and practices.
Asked about the potential for EFVS technology to enhance his fleet’s operations, Morrissette is on the lookout for new applications.
“We are looking at everything, paying attention to new opportunities and technology and identifying if it’s scalable for our company,” he said. “Any proven technology [that could] extend our safety margin and our ability to save lives would be something worth considering.”
That proof may be coming soon for the rotary-wing market.
In April, Elbit Systems said it was partnering with the FAA to research operational concepts for enhanced flight vision systems in helicopters, installing its Heli-ClearVision system in the agency’s Sikorsky S-76 at its William J. Hughes Technical Center near Atlantic City, New Jersey. In July, Astronics Max-Viz said it was teaming up with the FAA on the research, too.
Enhanced vision systems would enable use of technologies other than natural vision to land at a helipad or heliport. There are no regulations yet for such systems on helicopters that fly to onshore or offshore helipads or heliports. Officials hope the study may lead to a possible application of these systems. The Max-Viz 2300 and Max-Viz 1500 sensors will be part of the study.
New Rule Fosters Innovation
The new FAA rule for enhanced vision systems is surprisingly flexible — and deliberately so, says the industry, to avoid language that could hamper innovation.
“The FAA really wrote the rule agnostic of technology,” explained Gulfstream’s Hausmann. “Typical FAA practice would have been to describe in a lot of specificity particular technology for a capability they are certifying. The EVS land to rule was intentionally written not to do that. While the rule discusses IR-based EVS systems, it is not limited to that, so the rulemaking is already in place to allow manufacturers to innovate with other technologies.”
NASA hopes to leverage the ruling’s flexibility as it looks to develop a next-generation external vision system for supersonic aircraft. NASA has stated in published reports that these jets will not only reduce flight time for international travelers, but also will lessen jet noise to well below that of the Concorde. Bailey said the flight crew would rely entirely on electronic vision equipment.
“The next step is technologies that better penetrate all-weather conditions, such as combining millimeter-wave radar with forward-looking infrared systems,” he added, explaining that rather than having to wait for a new rule, NASA must simply “prove that we have the equivalent level of performance to meet the intended function.”
Bailey predicts that the commercial market will begin to see new EFVS systems that leverage millimeter wave radar in fewer than five years. The military sector is the innovation leader in this area, having long dealt with the problem of landing special operations rotary-wing aircraft in white-out and brown-out environments, Bailey said.
Military Visibility Requirements Driving Next Wave of EFVS Innovation
Nearly a quarter of all military aircraft crashes and 44% of aviation fatalities since combat operations began in 2002 in Afghanistan and Iraq were caused by degraded visual environments (DVEs), such as brownout, smoke, sand, snow, rain, night and fog conditions, according to statistics from the U.S. Army Combat Readiness Center. DVE occurs when aircrews experience low or zero visibility during takeoff, normal flight and landing.
“These environments restrict both commercial and military operations,” said Greg Cox, corporate VP of the communication, navigation, surveillance/air traffic management business area for Sierra Nevada Corp.
Sierra Nevada has spent more than a decade testing different EFVS sensor combinations, both on the ground and in flight. Key to solving the DVE problem using EFVS technologies, said Cox, is understanding the environmental conditions that need to be mitigated, the mission or flight profile and the obstacles requiring detection and display.
“No single sensor is capable of mitigating all forms of DVE,” said Cox. “Each sensor’s performance is a trade-off between obscurant penetration and image resolution. A truly successful EFVS sensor package will include multiple sensors, each optimized for the environment and the segment of the flight profile they perform the best in, and then fused in real time to provide the aircrews and flight computer with the required imagery and data to enable successful operations.”
Sierra Nevada said it uses a multi-sensor suite fused in real-time with terrain, imagery and obstacle data that is then integrated with symbology and command guidance to restore the visual cues for all modes of flight, in both natural and induced DVE. The company is exploring the strengths and limitations of two-dimensional and three-dimensional sensors and their application in multi-sensor fusing environments.
“Our primary sensor is a 94 GHz millimeter wave radar, which was specifically designed and optimized for mitigating DVE in aircraft. We have also tested and fused multiple light detecting and ranging (lidar) sensors and long-wave infrared (LWIR) cameras,” said Cox, who emphasized that sensor fusion is key to enabling the integration of dissimilar sensor technologies while flexibly accommodating new sensors as they become available.
“As true DVE systems are fielded, the military will be able to conduct operations without restrictions of dust, fog, snow “ and other environmental hazards, said Cox. “It also reduces the landing minimums for approaches in instrument flight rules conditions.”
Sierra Nevada expects EFVS systems to be standard on commercial aircraft within the next five years. AVS