Max-Viz Enhanced Vision Systems FAQ

How EVS Works and EVS Specifications

Enhanced Flight Vision Systems (EFVS) are currently defined in FAA exemption 91.175. This exemption requires the use of a Heads Up Display (HUD) or a Head Mounted Display (HMD) coupled with a specially qualified Enhanced Vision System (EVS). Under the certain conditions of this exemption (and at certain airports and in an IMC flight), if a pilot reaches the published Decision Height or Minimum Descent Altitude and is unable to see the runway landing environment except through a regulatory compliant EFVS system, the pilot is allowed to descend down to an altitude of 100 feet above touchdown zone elevation. At that point, the landing environment must be acquired with the pilots natural vision and if not, the pilot is required to abort the landing attempt. The proposed new rule would eliminate minimum height and, under certain conditions/restrictions allow the pilot to effectively land the aircraft using only the EVS displayed on the HUD. For flight crews to take advantage of EFVS, they must be specially trained and the EVS equipment needs to meet special requirements (and be tailored for use with each specific HUD).
Conventional IR systems are cryogenically cooled, that is, they require a mechanical cooler to keep the detector very cold in order to "see" small temperature differences. The Astronics Max-Viz system uses new, uncooled microbolometer technology to attain equivalent performance without the need for complicated, heavy and expensive cooling mechanics. Some of the older, cooled system are sold today at up to $500,000 per system. Astronics Max-Viz technology is designed to be simply installed and incorporated into aircraft operations to improve existing operational flight safety.
  • Dimensions: Camera: 2.8″ (71mm) diameter x 6.8″ (172 mm) length Power Module: 3.75″ (95mm) width x 5.0′ (127mm) height x 2.25″ (57.2mm) depth
  • Weight Camera: 2.5 Lbs (1.13kg) Power Module: 2.65 Lbs (1.20kg)
The EVS has heaters that prevent the accumulation of ice that otherwise might adversely affect normal operations. Heater operations are automatic dependent on ambient temperature and are thoroughly tested during manufacturing. Qualification and production performance tests performed on our systems have met or exceed FAA requirements.
Astronics Max-Viz products produce a video signal that interfaces with RS-170/NTSC (basically black and white video) compatible displays. Astronics Max-Viz has effectively interfaced for display on PFD / PND, MFD and EFB as well as countless quality dedicated displays. Contact your authorized Astronics Max-Viz dealer or Astronics Max-Viz directly for additional details and to find out what display options are recommended with your EVS system or airframe. We have a solution that will work for you.

EVS and EFVS Regulations:

Regulatory Position Papers:

Helpful Links:

In contrast to visible light energy, infrared energy typically passes through dirt or bug-debris build-up on the window. As such, the Sensor window requires only occasional cleaning with mild liquid soap and water or isopropyl alcohol, and a soft cloth. The use of corrosive cleaners such as Corrosion X can damage the RTV seals and coating on the germanium window. Cover the exposed Astronics Max-Viz system completely before using products like Corrosion X and Ammonia. Do not use abrasive cleansers or cleaning pads on the germanium window. Abrasive cleaning can damage the window coating. Do not use any cleansers with ammonia. Ammonia will remove the window coating.

How EVS Compares To or Is Used In Conjunction with Other Systems

EVS is real time and updated every 17 milliseconds ("live" for all practical purposes); SVS data may be days or weeks old. SVS cannot show real time obstructions such as aircraft, people, wildlife, construction equipment or fuel trucks. Current SVS versions may also be missing new airport infrastructure such as buildings, taxiway markers, signs and fences. On approach, EVS can help you get a good look at unfamiliar airports before landing. In an emergency at night away from the airport, SVS doesn’t show trees, buildings, highways or streets. EVS, on the other hand, can help you find a safe place to land.
Synthetic Vision Systems (SVS) provide situational awareness by placing a 3D geographical image on a cockpit display using terrain, obstacle and other databases. Navigation and positional information is obtained from GPS and Inertial Reference Systems. SVS presents a very nice "clear day" view of the world, but is only as good as the most recent update to the database which can be days, weeks, or even months old. By contrast, Enhanced Vision Systems (EVS) provide pilots with a clear live video image of the world that he could not otherwise see at night, and in poor visibility. Combined Vision Systems (CVS) is a term applied to the combination of EVS and SVS whereby EVS is used to provide a real time confirmation (validation) of the SVS environment. In CVS the pilot is doing the comparison and alignment of the two systems. Verified Combined Vision Systems (VCVS) is a term applied to use of smart processing to verify and correct GPS positional error (if any), automatically resolve differences between SVS and EVS and align the images.

NVG’s and EVS systems are entirely different. Each system has its own strengths and weaknesses. EVS systems utilize thermal imagery based upon Infrared sensors "microbolometers " that are heat sensitive and can detect temperature changes of less than 1/10th of 1 Degree C. These sensors detect Long-Wave Infrared (LWIR), Short-Wave Infrared (SWIR), or Mid-Wave Infrared (MWIR) energy, depending upon the manufacture and type of sensors being utilized. Astronics Max-Viz EVS systems utilize un-cooled LWIR microbolometer based sensors that detect energy in the 8-12 micron range, presenting that energy in a black and white "video appearing" format. This image can be displayed in the cockpit on dedicated displays as well as many multi-function, primary flight or primary navigational displays. The EVS image can also be presented in cabin displays as desired by the end-user.

Night Vision Goggles use light-amplifying technology. This technology takes the small amount of light that is available in the surrounding area (such as moonlight or starlight), and converts that light energy (scientists call it photons) into electrical energy (electrons) presenting an enhanced visible image to the pilot. These electrons pass through a thin disk that’s about the size of a quarter which contains more than 10 million channels. As the electrons go through these channels, they strike the channel walls and thousands more electrons are released. These multiplied electrons then bounce off of a phosphor screen which converts the electrons back into photons presenting a green- hued amplified re-creation (think T.V.) of the scene being observed through the NVG eyepiece.

EVS provides daylight vision in darkness, poor visibility, smoke, haze, smog, dust, and light fog. EVS can see through these conditions because thermal energy from the environment is able to penetrate the density of the atmospheric particles when they are smaller than 12 microns. EVS can be limited in heavier atmospheric conditions or when the environment does not have thermal variation (or contrast) which is necessary to present a temperature based image. At rare times, a phenomenon called "thermal cross-over" occurs where objects in the environment transition through an identical thermal gradient. At these times, an object in the foreground may fade to very low contrast or may not be visible for a very brief period of time even during period of clear VFR operations. EVS can also be degraded during periods of heavy rain depending upon sensor mounting location, airspeed and airflow. This can be compared to driving a vehicle in heavy rain without windshield wipers.

NVGs are operationally effective at night and will not work in complete darkness without additional IR illumination. NVG’s can only be utilized during the day with training filters and prolonged use is not recommended since it can damage the image intensifier. New Gen 3 and Gen 4 NVG technology is very good and it is possible to see through thin / light obscurations such as smoke, haze, smog and fog. However, it is important to note that NVG’s may actually be lulling you into a false sense of security, since these conditions may be deteriorating to a point where visibility through the goggles is no longer possible. Continued flight into denser atmospherics can result in the NVG’s shutting down and leaving the pilot unaided in an Inadvertent Instrument Meteorological Condition (IIMC) scenario. NVG’s cannot see through dust, heavy snow, heavy rain. Degraded NVG operations can also occur in mountainous terrain due to shadow’s affecting the NVG’s ability to gather light. NVG’s can also subject to dimming during periods of high illumination that could be caused by bright moon light, ambient light from large cities or high intensity search lights. Aircraft cockpit lighting, internal lighting, and external lighting, must also be modified for use with NVG’s so that they do not cause interference or degrade NVG viewing capabilities.
One should note that each one of these systems complements the other during nighttime operations. EVS utilized in combination with NVG’s provides optimal viewing results. EVS image through the various atmospheric conditions much more effectively than NVG’s. EVS additionally can better differentiate between MVFR and IFR conditions during en route flight which provides a significant improvement in IIMC avoidance. NVG’s, however, improve the lateral situational awareness and are very effective in providing good imagery during periods of low thermal contrast. It is the synergy of these two technologies looking at the environment through an enhanced visual and thermal comparison that provides this overlapping safety solution. The combination of these two systems will change the way night operations are conducted by increasing safety, while preserving precious assets such as flight crewmembers and aircraft during periods of reduced visibility and darkness.
Helicopter Terrain Awareness and Warning System (HTAWS) is a helicopter variant of the fixed wing Terrain Awareness and Warning System (TAWS) or Ground Proximity Warning System (GPWS) equipment that was developed and implemented to reduce the occurrences of Controlled Flight into Terrain (CFIT) in fixed wing aircraft. HTAWS presents both aural and visual indication of closure rates or proximity to terrain or objects that are resident within the HTAWS database.
HTAWS systems are highly developed and can take multiple inputs from the aircraft (i.e. power, airspeed, attitude, climb or descent rates, etc.) and flight path data to determine if the aircraft will approach or impact terrain and / or manmade objects that are resident within the independent database.
HTAWS indications are either aural (cautions or warnings of terrain or obstacles or proximity of the tail of the aircraft in some instances to the ground) or visually presented on multi-function displays (MFDs) or navigation displays in varied colors associated with the severity of the flight profile. The HTAWS system takes the aircraft flight profile and compares that data to the resident digitized terrain and obstacle information within the system and correlates the closure rates to provide the pilot with adequate reaction times to reduce the potential of a hazardous condition.
HTAWS data bases require regular updates to ensure that new hazards, obstacles, and terrain updates are displayed accurately. It is also important to note that HTAWS data bases could display variances depending upon GPS accuracy and actual aircraft position. Astronics Max-Viz EVS systems complement HTAWS by providing real time views of the actual position in relation to terrain, hazards, and obstacles. Pilots can process visual information quickly, confirming HTAWS reliability resulting in optimal situational awareness and safer operational parameters.

FAA Rulings on EVS

Astronics Max-Viz embraces the FAA initiative to accept Enhanced Vision Systems (EVS) as a time tested technology that is a reliable and useful tool in allowing pilots to taxi, take off, and land in situations where they are not permitted to do so today. Astronics Max-Viz agrees that a HUD is a viable means to provide EVS information to the pilot, but does not believe it is the only mechanism for safely displaying EVS information. Various members of the Canadian and European regulatory and aviation communities believe EVS information can be safely displayed on a Head Down Displays (HDD) particularly when there are two crewman in the cockpit. Astronics Max-Viz also believes that Synthetic Vision Systems (SVS) when properly registered to the real world (i.e. validated by EVS) and presented on a HDD can be used with an equivalent level of operational safety in similar approach, landing, and take-off profiles.
Not as written; unless using a system currently qualified under the specifics associated with FAA 91.175. This proposed ruling is sure to prompt discussion among helicopter operators and may lead to a separate proposed rule that is rotary specific; taking into account the unique environment and the special procedures under which helicopters opereate?
You do not need to be concerned. Approval for installation of the Astronics Max-Viz system on your aircraft comes from a Type Certificate (TC), Service Bulletin (SB) or Supplemental Type Certificate (STC). The label only lists models for which Astronics Max-Viz has FAA Parts Manufacturer Approval (PMA). The reason there is a label on the EVS system is all PMA holders are required to label their products (Title 14 of the Code of Federal Regulations (14 CFR), part 21 Certification Procedures for Products and Parts, section 21.316).

Yes. This announcement will generate more discussion about EVS and we suspect the non-HUD providers will get actively involved in trying to get the ruling amended to include other kinds of devices. All of this discussion will find its way into the news and that means that more people will become aware of the current and potential benefits of EVS.

Questions About the Value and Financial Justification for EVS

With EVS, pilots can see better in situations where natural vision may be compromised (such as at nighttime, smoke, smog, or haze); if the pilot can see, he can avoid. EVS cost is typically less than 5% of the hull value of the aircraft. Without taking into account the potential (or cost) for harm to humans, accidents involving Controlled Flight Into Terrain (CFIT), runway incursions, and ground related incidents due to loss of visual reference or spatial disorientation often exceed the cost of EVS. EVS can lower the potential for (and cost of) accidents, so insurance companies, such as Aggressive Insurance, offer discounts on aircraft insurance premiums.
Because EVS is a safety and productivity enhancement that adds value to the aircraft, you may be able to take advantage of favorable tax treatment. Please consult your accounting department and/or tax advisor for additional advice as to whether you qualify. Additionally, numerous Astronics Max-Viz customers have reported insurance savings associated with the addition of EVS to their airframe, however, we are not qualified to provide specific insurance information and therefore you should consult your insurance professional.
Max-Viz was founded in 2001 by industry veterans; supported by some of the country’s finest venture capital firms. In 2012, the company was purchased by Astronics Corporation but remains intact as a business unit and wholly owned subsidiary. As a wholly owned subsidiary, we don’t release financial information, but our parent company is publicly held (NASDAQ: ATRO) and information is available on the parent company website (

EVS Export Information

No. Astronics Max-Viz products do not fall under ITAR Regulations. All Astronics Max-Viz EVS products have been designated to be under the Department of Commerce (DoC) Jurisdiction.
Yes. Astronics Max-Viz EVS, like other EVS Thermal Imaging Camera technology, is Export restricted, and must meet Export license requirements. An Export license exception maybe applicable, see the EAR for requirements prior to exporting EVS technology.
Astronics Max-Viz exports our EVS technology directly to the Purchaser, for any sale outside the United States. The US Government form BIS-711 is required to be completed by the purchaser, together with a Statement of Ultimate Consignee or the Max-Viz Foreign Customer information form
Export applications normally take 30-45 days. However, complex applications may extend the approval time.
Once Astronics Max-Viz has a program commitment, a Purchase Order, and deposit, we ask the customer for a completed BIS-711 and Astronics Max-Viz Foreign Customer Information form. The document links are available below. The Export license application is submitted to the DoC, and the application process is underway, and can take 30-45 days. If additional information is needed, the customer is notified by Max-Viz.  The DoC may send Terms and Conditions that require the End-User to acknowledge and accept. The terms and conditions, once accepted, are sent back to the DoC, and the export license can be finalized. Astronics Max-Viz is authorized to ship the EVS equipment upon receipt of the Export license.
Yes, the United States has determined certain countries as Export Controlled or Embargoed Countries, per the Export Administration Regulations (EAR), §746, “Embargos and other Special Conditions”.  Because these designations can change rapidly, please consult the EAR and or the Department of State for further information. See the links below for assistance.
The Export Administration Regulation §740.20, Strategic Trade Authorization (STA) License Exception, allows exports without obtaining an export license if all the conditions listed in the STA exception §740.20 of the EAR can be met. Complete a BIS-711 and an STA Foreign Customer Information (below) and submit to Max-Viz with your Purchase order. If the Export qualifies, and the export destination is to one of the STA countries listed below, an STA Exception may apply:

Australia – Austria – Belgium – Bulgaria – Canada – Cyprus – Czech Republic – Denmark – Estonia – Finland – Germany – Greece – Hungary – Iceland – Ireland – Italy – Japan – Latvia – Lithuania – Luxembourg – Malta – Netherlands – New Zealand – Norway – Poland – Portugal – Romania – Slovakia – Slovenia – South Africa – South Korea – Spain – Sweden – Switzerland – Turkey – United Kingdom

This would be a violation of the Export Administration Regulations (EAR). We would not be authorized to sell product to anyone under these conditions. Astronics Max-Viz, Inc. Enhanced Vision Systems products are regulated by the U.S. Department of Commerce in accordance with the Export Administration Regulations.

Astronics Max-Viz Sales Assistance:
If you need further information, contact Astronics Max-Viz sales.

Export Administration Regulations:

U.S. Government BIS-711 form:

Contact Astronics Max-Viz

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