Features Innovations New Technologies
A View to Safer Flying

Night vision systems offer pilots the ability to literally see in the dark, reducing the risk of accidents and collisions. If you haven’t put a new generation set on, you owe it to yourself just to admire the technology. Enhanced vision systems in contrast improve the operator’s ability to deal with limited or reduced vision systems, and as such do not bring operators into situations they would not otherwise fly in without the technology. They can aid in darkened situations, but also in light fog, rain, and smoke.

Training is paramount to safety. Here Night Readiness LLC’s Virtual Terrain Board System (VTB) provides 360 degree panoramic views in a virtual environment for NVG training for flight and ground operations.

Still, all this wonder technology comes with limits, chiefly around how and where it is applied. In Canada, the industry is considering the future direction of much of this technology in a NVIS Working Group under the Helicopter Association of Canada in conjunction with Transport Canada. It is being headed up by Bob Toews, chair of HAC’s IFR Committee and long-time member of the aviation team at STARS – Alberta’s not-for-profit EMS provider that has considerable NVIS experience. The group will hold its first meeting at the HAC convention in April in Quebec City.

In the meantime, to find out what they are and learn more about NVS, Helicopters magazine convened a ‘virtual round table’ of four respected NVS equipment suppliers, as well as one enhanced vision systems supplier. Many of these are also vastly experienced military, EMS and civilian pilots invloved in both equipment and training.

A Eurocopter EC-130 with the Max-Viz EVS camera on the right lower nose. The system helps out in low, or almost no, light situations as well as light fog, rain, snow, or smoke. (Photo courtesy Night Flight Concepts and Night Readiness)

Our virtual panellists are Casey Howlett, project coordinator with Aero Dynamix; Kim J. Harris, director of operations with Aviation Specialties Unlimited; Bob Yerex, director of sales with Max-Viz; Randy Rowles, VP business development and director of training with Night Flight Concepts; and REBTECH president Richard Borkowski. In all cases, the need for training, education, and informed purchasing come to the fore.

Helicopters: What precisely are Night Vision Systems (NVS)?
Kim Harris: When the term “Night Vision Systems” is used, the image most people may think of is the pilot with a set of Night Vision Goggles (NVGs) mounted to a helmet. There is more.

Casey Howlett: Complete night vision systems are much more complicated than that and then add in the extra requirements as set forth by the FAA and other governing agencies, it can be a very difficult system to design and provide.

Richard Borkowski: Night vision systems for helicopters consist of NVGs and the proper lighting of instrument panel, exterior lights and any other lights associated with the aircraft that can be illuminated while in flight.

Helicopters: How do NVGs ‘see in the dark’?
Randy Rowles: NVGs work by taking the ambient light available, multiplying that light by thousands of times, and then displaying an electronic image created by the varied level of energy brought into the image tube. The image begins as photonic energy … and is converted into electrons. Once converted, the electrons are intensified thousands of times. This electronic image is then converted back to photonic energy (photons) and displayed on a screen for the eye to see.

There are several different NVGs within the US industry. They are ITT F4949, L3 (Litton) M949, and the Nivisys NVAG-6. The Nivisys NVAG-6 is the only FAA approved NVG obtaining TSO C-164 approval in 2008 (Ed note: An FAA Technical Standing Order means an article meets specific airworthiness requirements; it is not necessarily an indication of its optical performance).

Helicopters: In the same vein, what are Enhanced Vision Systems (EVS) and how do they work?
Bob Yerex: Enhanced Vision Systems (EVS), which utilize infrared technology, sense very small temperature differences in objects and their background to allow the pilot to view the imagery on dedicated installed monitors, multi-function displays (MFDs) or other appropriate video-capable displays. The image presented by EVS is grey scale, and from the pilot’s perspective appears like a real-time black and white video of the outside environment.

Helicopters: What is the state of the art in NVS today?
Borkowski: State of the art these days includes the aircraft being filtered to the point where there is absolutely no interference to the [night vision] goggles. The colors of the display can remain the same as they were prior to the filtering. Newer and more advanced filters allow for these changes and are incorporated internal to the instrument or display.

Howlett: Goggles are forever evolving as new technologies present themselves. Operators need to do their homework and investigate all available goggles and cockpit modification techniques to make sure they are getting the highest optical performance.

Cockpit modifications and lighting are crucial to proper NVG implementation. From left are unfiltered instruments through NVGs; filtered instruments through NVGs; and filtered with the unaided eye. (Photos courtesy REBTECH)

Yerex: In enhanced vision, the second generation Max-Viz EVS-1500, having a dual optical Field of View (FoV), provides the pilot with both a wide angle FoV of 53 degrees wide by 40 degrees vertical; with the addition of a narrow FoV of 30 degrees wide by 22.5 degrees vertical. The ability to have both a “situation awareness” FoV in the wide angle, and a slightly better than 1:1 image compared to the naked eye in a second generation sensor design provides the pilot with the best of both worlds.

Howlett: Technological advancements in IR suppression filters and lamps have made great improvements possible for providing NVG compatible lighting to the cockpit environment. With new types of filter and new types of lamps, it is now possible to find the right combination for maintaining proper colors and light levels for any application.

Helicopters: What NVS tech is under development?
Harris: ITT is constantly working on improving existing technology as well as developing new systems that will provide greater performance in a broad array of conditions and lighting environments while reducing the size and weight of the units.

Howlett: Type VI & Type VII Edge Lit Panels are now starting to hit the market with the Bell  being the first OEM aircraft to come off of the assembly line with Type VII panels. Both Type VI and Type VII panels are built using the latest LED technologies. Type VI panels allow for thinner panel applications than ever before and because they are both LED-based, their power consumption is considerably less than alternative versions.

Helicopters: The Big Question – Do Night Vision Systems reduce accidents?
Harris: That is a difficult question. Does any new equipment [such as] NVGs, TAWS, TCAS reduce accidents? Until definitive studies have been conducted, we cannot realistically answer this question.

Howlett: I do not have any evidence that supports the stance that NVGs reduce accidents since NVGs have not yet been mandated for night operations by the FAA. However [The FAA fact sheet ‘Helicopter Emergency Medical Service Safety’] does identify Controlled Flight Into Terrain (CFIT) and pilot spatial disorientation/lack of situational awareness in night operations as two of the main causes for night operation crashes. Operators who fly night time missions such as EMS, law enforcement, and search and rescue typically have low level flight routines and landings that take them into uncontrolled areas where safety factors such as trees, power lines, towers and terrain could have been avoided had the crews been using NVGs.

Yerex: EVS technology is effective both day and night, and because the flight appropriate go/no-go decisions are still limited by the naked eye, is safety specific in its application. The drawback of EVS is that neither the FAA nor the NTSB has taken the time to fly the technology and evaluate the effectiveness as a risk mitigation technology.

Borkowski: Night vision goggles increase situational awareness which increases aircraft and aircrew safety. However the use of NVGs should not change your minimum flight requirements.

Rowles: [In] Using NVGs … the industry must respect the product for its capability and more often its limitations. They are not in any way a silver bullet or smoking gun to a safer industry, but they do provide a safer operating environment for pilots and crews with proper training and comprehensive procedural structure. The fact is a pilot can see at night what he/she could not see before. This within itself is safer, but there are limitations to this capability.  

Helicopters thanks all our roundtable participants. The views expressed here are not necessarily those of the magazine.