Enhanced Vision Systems (EVS) are stepping up as a superior set of eyes onboard the aircraft to help the pilot see in darkness and “through” haze, smog, smoke and light fog, presenting a real-time picture of what’s ahead and allowing the pilot to both fly and land the aircraft more safely in low visibility. The technology provides an output from an infrared camera and incorporates information from multiple sensors on board the aircraft to provide a picture that improves situational awareness, enables pilots to conduct flight operations in low-visibility conditions and perform lower landing minimums.
Companies feel that as systems become more affordable alongside upcoming FAA certification this may allow for lower landing minimums. With the technology, rotorcraft, general aviation and commercial markets aren’t far behind the more mature business aviation industry. Avionics Magazine’s 2015 Enhanced Vision Systems survey backs up this assertion, with nearly 60 percent of respondents citing that they have the need to acquire EVS technology for their current fleet of aircraft.
|The view from Elbit Systems’ Enhanced Vision System (EVS) camera.
Photo: Elbit Systems
Enhanced Vision Systems (EVS) are slowly but steadily becoming standard in the business aircraft market. With biz av operators more likely to take the risks posed by new technology and more willing to cough up the cash, systems have become standard on aircraft such as the Pilatus PC-24 jet and Gulfstream G500/G600.
Gulfstream was the first manufacturer to certify for Enhanced Flight Vision System (EFVS) in civil aviation and is continuing its efforts by making Elbit Systems EVS III standard on all G500/G600 business jets.
The EVS III, a third-generation infrared system, builds on earlier systems (EVS I and II). It uses an infrared sensor with four times the resolution of their previous EVS to detect approach and landing lights in low-visibility conditions. The image from the EVS III is displayed on a Head-Up Display (HUD) and depicts a real-time picture of the scene in front of the aircraft. It also qualifies as an EFVS, according to the FAA, and pilots can use it to continue approach to 100 ft solely using the enhanced vision system, provided they see the landing area at or above decision height, Mike Mena, director of G500/G600 flight deck, electric power and wiring at Gulfstream Aerospace, says.
While biz av operators often have the cash and inclination to try out new tech, Mena notes that EVS can also allow them to stay competitive in the market where other markets, such as GA or air transport, don’t have the need.
“Business aviation has a competitive need to provide its customers capabilities in terms of mission performance and safety,” Mena says. “Unlike airlines that fly fixed routes, business jets fly almost anywhere — and often into smaller airports that don’t have the ground infrastructure that large airports do, such as CAT III Instrument Landing Systems (ILS).” EVS is just one of the necessary technologies that business aviation operators have on board to minimize reliance on ground infrastructure, with Synthetic Vision Systems (SVS), Required Navigation Performance (RNP), Localizer Performance with Vertical Guidance (LPV) and other technologies also playing a role.
EVS and these technologies can help business aviation operators land in difficult, smoggy or less-equipped airports, particularly in countries with less infrastructure, as they are often asked to do. “When you start to go East to Asia, China, South America and those areas, airports start to be less-and-less equipped, and also those places like India and China, suffer quite a lot from air pollution or smog. This limits visibility quite significantly,” says Dror Yahav, vice president of commercial aviation for Elbit Systems. “When we analyze the business case, the research shows that in these particular areas — South America, China, India and so on — the value of enhanced vision systems is rising quite significantly in terms of operational efficiency and safety.”
Nearly a quarter of respondents to our 2015 EVS survey said they use Elbit Systems EVS aboard their aircraft, and the already successful technology is continuing to evolve. The most notable upgrade is the company’s ClearVision EVS, which has been selected by Dassault Falcon for its 7X jet. It includes a fusion of sensor images and synthetic vision and is available as a Head up Display (HUD) or as a wearable technology for the pilot. The six-sensor, multi-spectral EVS maximizes detection capabilities by viewing in various spectral bands. Over current EVS benefits, the system also offers pilots the ability to detect LED and incandescent runway lights at long ranges in low visibility, something EVS that rely on heat sensing can’t currently accomplish.
“The traditional EVS we have out in the market are designed to see heat, they are infrared technology and they are designed to see the heat that each camera produces,” says Yahav. “More-and-more, airports are starting to use LED lighting and these lights are cold lights, which requires that we develop new cameras to see those LEDs because they can’t be detected by traditional technology.”
ClearVision is looking to up the ante in other ways as well. Most recently, developers integrated functions into the system that will allow it to detect volcanic ash, something that, until now, was previously undetectable by EVS and which is often imperceptible to the naked eye. Elbit is looking to continue evolving the system, not entirely through enhanced functions, but through a wider range of functions that will eventually act as something of an automated co-pilot.
“The aircraft has a lot of information that is being gathered by the systems, but it doesn’t have another set of eyes looking independently of the pilot outside and analyzing the environment from a visual perspective,” said Yahav. “EVS can be, or should be, or will be, another pair of eyes for the pilot, utilizing all those sensors that we have out there we can see much more of the environment than the pilot can see.”
Rotorcraft and General Aviation
|Honeywell’s combined vision system, which marries enhanced vision systems with synthetic vision systems, in a helicopter cockpit. Photo: Honeywell
In November 2014, Astronics Max-Viz, headquartered in Portland, Ore., launched the Max-Viz 1400 Enhanced Vision System for GA and helicopter pilots. The system, like many EVS, is thermal-based and uses heat, rather than light, in the form of an infrared camera to create a 640 x 480 pixel resolution picture of the world ahead. The company, which was established in 2001 for the purpose of designing and certifying EVS, has previously developed systems for the business aviation sector and launched their first model (the Max-Viz 1000) in 2003 when high-end EVS going into intercontinental business jets coupled with HUD were going for almost $1 million, according to Elliot Troutman, executive vice president of Max-Viz operations.
Now, however, systems are becoming cheaper and therefore, more accessible to civil aviation pilots, who tend to have tighter budgets than deep-pocketed business aviation operators. To make the systems affordable and amenable to GA and helicopter operations, the systems that companies use for civil EVS tend to be less sophisticated, but can still provide plenty of benefits.
“The functionality of the Max-Viz 1400 system for GA and helicopters is fundamentally the same as the systems found in higher-end more expensive systems. Some of the higher end systems have greater resolution/sensitivity or may be coupled with additional sensors (e.g. visible light detectors) to provide a better picture, but they all have the same objective: to enhance our human vision when visible light is low (e.g. night) or obscured (e.g. smoke),” Troutman says.
The Max-Viz 1400, which is expecting FAA Type Certification and Standard Type Certification (STC) this year, enables pilots to see four to 10 times better than unaided vision. Still, the technology isn’t perfect and Troutman admits that there are certain fogs the EVS cannot see through.
“If the fog is thick enough and the water droplets are big enough, the thermal energy that the EVS detects cannot get through. These fogs are almost always the ones you cannot see through with your eyes,” says Troutman. To mitigate these hazardous situations, Troutman suggests a certain amount of “common sense” when operating aircraft in reduced visibility.
Knowing the limitations, helicopter and GA pilots can still see plenty of benefits from the systems, depending on the amount they fly in reduced visibility conditions. One area that Troutman sees the technology as being particularly valuable is in firefighting operations.
“Max-Viz systems see through smoke like it is not there,” says Troutman. “That means that pilots of firefighting aircraft can see through the smoke, spot and target the fire in ways they cannot do today.” In this way, Troutman believes the fire can be put out more quickly, with fewer sorties and, therefore, less cost, saving property along the way.
Much like business operators, EVS can also extend benefits to general aviation pilots at many of the smaller and less sophisticated airports they fly to regularly.
“Not all airports have the costly, ground-based technology and infrastructure of an O’Hare airport that enables high traffic volume to operate safely. EVS is a cost-effective way to “light up” secondary airports so that the pilot can see and clearly avoid aircraft, wildlife and other obstructions that might be in the way. That makes those airports safer and more usable — and those airports cost less to use and maintain,” says Troutman.
EVS has yet to enter the air transport market, with cost and regulation acting as the main deterrent.
“The effective reason why EVS hasn’t moved beyond the business jet market is that there has been no regulatory framework for it to do so,” says Alan Hnatiw, director of advanced warning vision systems and satellite communications at Esterline Communications. “Right now, there’s no way to get FAA approval for reduced landing credits for air transport or part 121 aircraft operators. Hopefully, with the FAA working on new regulations for EVS for the new air transport market, which are expected to come out this year, that will have a significant impact on the air transport market.”
Hnatiw sees this changing effectively within the next few years, as the technology becomes, cheaper, more sophisticated and its benefits to the air transport market become better understood.
“We’re quite confident that EVS being used in the air transport market is the next major market for EVS,” says Hnatiw. “The main obstacle is getting people familiar with it. Going forward, one of the key areas is education, allowing operators to understand the benefits of the automation.”
Pending Lower Landing Minimums
The FAA has recently put forth a Notice of Proposed Rulemaking (NPRM) to allow operators to use EVS in lieu of natural vision to continue descending from 100 feet above the touchdown zone to the runway and land on straight-in instrumentation approach procedures under new Instrument Flight Rules (IFR).
“Prior to the rule, the pilot still has to make that transition at 100 feet. Now, the rule is saying that you can transition without ever having natural vision,” Thea Feyereisen, technology fellow in the flight safety group at Honeywell Aerospace says. “In some ways it makes the operation easier from a pilot point of view in not having to make that transition.”
According to ur 2015 EVS survey, only 13 percent of respondents were interested in acquiring EVS for the sole purpose of performing lower landing minimums. Improved situational awareness ranked in as the top reason, followed closely by the ability to conduct operations in low visibility.
While it may not be the main driver, regulation permitting lower landing minimums may help encourage pilots to equip with EVS, with some U.S. operators already seeing the benefits. “FedEx petitioned for, and the FAA granted, an exemption that permits them to use EFVS-equipped aircraft to continue an approach to destination airport when the weather is reported to be below minimums,” the FAA says.
The FAA is still evaluating the NPRM, but operators expect the rule to take effect sometime this year. And as the technology evolves, the new landing minimums using EVS can offer continued improvements.
“The EFVS NPRM proposed a performance-based rule, so that additional EFVS operations could be approved in increasingly lower-visibility conditions as the technology matures and improves,” the FAA says.