February 1, 2003

Accessories: Being Green—Then Seeing Green

A firsthand report from two high-time pilots who went through Bell Helicopter’s new civilian night vision goggle training course.

by Ron and Shannon Bower, Reporting from Fort Worth, Texas

Editor’s Note: A father/son team of dual-ATP rated pilots, Ron and Shannon Bower recently attended the first (and only) FAA-approved Part 141 training course for civil aircrews using night vision goggles (NVGs) at Bell Helicopter Textron’s Customer Training Academy in Fort Worth, Texas. Neither Ron nor his son Shannon had previously flown with night vision goggles.

In this report, they describe their educational experience and the state of this safety-enhancing NVG technology, as it applies to civil helicopter operations. They also walk you though the curriculum for the ground and flight training "under the goggles."

Ron and Shannon have a combined 58 years and 15,000 hours of licensed flying experience, including hundreds of hours of night VFR and IFR cross-country.

This new five-night course included eight hours of classroom instruction and 7.5 hours of night flight instruction using NVGs. Shannon graduated from both the ground and flight portions, while Ron graduated from the ground portion and rode in the back seat of the helicopter on all of Shannon’s flights taking the NVG pictures for this report. Ron also flew a 40-minute NVG familiarization flight.

Both men researched and wrote this article together. It is written in Ron’s voice and from his perspective.

THERE IS NO DOUBT, AFTER attending the Bell NVG course, that my long-held perspective on NVG use in helicopters was quite wrong. Prior to taking this course, I viewed NVG use as dangerous, deadly, and very expensive. I harbored the preconceived notion that NVGs were only for military use, where sacrificial risks were part of the job.

My perspective has drastically changed. I now see NVGs as an essential safety-enhancing mission tool for many civil helicopter operations—particularly emergency medical services (EMS), airborne police, search and rescue, and other parapublic missions.

Today’s NVGs can significantly enhance safety in night flying, and are astoundingly useful tools in accomplishing any nighttime mission. They’re not just for remote areas with limited light sources.

Flying over the DFW metroplex, the dark areas that might be selected as emergency landing areas for non-NVG pilots became lit up showing unseen obstacles; shadowed and darkened backyards and parking lots were now bright, leaving no place for villains to hide; and dark, wire-strung rescue or medevac scenes showed almost like daytime.

I now wholeheartedly believe it to be much, much safer to use NVGs, than not using them for any night flying operation. Also, instead of being very expensive, the cost of installing NVG equipment in helicopters has being greatly reduced.

The reaction most people have to their first NVG helicopter experience at Bell’s NVG course is similar to the "WOW" reaction to a first helicopter flight. That was certainly my reaction. As I sat in the back seat for seven-plus hours wearing NVGs, I couldn’t seem to get over how "black" it was outside when I would flip the goggles up, and then how bright, clear, and defining it was when the goggles were down.

I don’t care how good your landing or searchlight is, or how good your pilot skill is; without NVGs, you’re missing significant, possibly critical, visual input at night. Today’s NVGs represent a quantum leap in improved safety.

NVGs were not available when I flew helicopters in Vietnam in 1965-66. The infantry was "experimenting" with early Starlight scopes that were large, heavy, fragile, and produced grainy images. If a Starlight scope were turned on during the day, it would burn itself out, a natural self-destruct mechanism for captured devices.

Early military helicopter NVGs in the 1970s and ’80s had many operational limitations. If a bright light was encountered, rather than burnout, protection circuitry was added to automatically shut them off —a rather unhandy feature. They, too, were heavy, peripheral-view blocking, and grainy, not offering the clear image quality that is available today.

In the case of newer NVGs, you put them on when you are ready for takeoff and leave them on until after you land. At Bell, the heliport ramp was lit with bright Halogen lamps, and they caused no noticeable degradation or problems. Also, in an almost pitch-black night, we simulated an EMS scene by landing near a fire truck with all of its strobes, headlights, and flashing lights on. Again, vision was far better with NVGs than without them. The internal circuitry of the NVGs automatically adjust to bright lights.

I know that many older helicopter pilots ("helicopterus-rex") share my previously negative opinion of NVGs. Some, as I was, have no first hand or recent (within the last four or five years) NVG experience. Many of these "seasoned" veterans are in decision making positions in flying organizations, and I suspect in aviation regulatory agencies worldwide. I strongly urge any organization whose mission requires safe night flying management to seriously look into today’s NVGs—you will really like what you see.

Learning to fly NVGs safely

With NVGs, as with any flying skill, initial and recurrent training is necessary. Bell Helicopter’s Customer Training Academy recognized the benefits of NVGs and developed the first (and still the only) FAA Part 141 Approved NVG Special Operations Course for civil helicopter flying. As with any new certification effort in aviation, it proved to be a lengthy process.

Two highly experienced NVG Bell pilots, Cornelius "Mac" MacMillan (chief NVG instructor), and Scott Baxter, (assistant chief instructor) led in the development and certification effort with the FAA. MacMillan and Baxter have more than 2,500 hours of NVG flight experience between them.

While the NVG course was designed for pilots, it is also valuable to other air crew members, helping them understand how night vision works, both in human eyes and with NVG equipment. Non-flying observers/crewmembers may attend the ground-school portion of the course, as well, to develop a better understanding of NVG operation. Short-course refresher training also is available.

The Bell 206 JetRanger is an excellent training platform for NVG training. But, the training is not aircraft specific, rather it is focused on NVG transferable concepts to any aircraft. Training of additional Bell NVG instructors is underway, and Spanish language NVG instruction will soon be available. In addition, for many public-use operators, the Bell NVG instructors will conduct custom on-site training in your own aircraft

For additional information on the Bell NVG course, go to www.bellhelicopter.textron.com/content/training/courses/nv/nvg.htm.

NVG hardware: What does it take?

The NVG industry terminology of "aided" versus "unaided" is an accurate way of describing how you conduct night flights. If you don’t use NVGs for night flying, you are flying "unaided." Why would someone choose to fly unaided, if "aided" flying is available, and significantly safer?

As with GPS, you don’t have to have a GPS to aid you in navigation—you can still navigate unaided using basic piloting (a map, compass, and clock). However, GPS drastically improves pilots’ positional awareness and results in a far safer method of navigating. Maybe in an even more drastic way, NVGs enhance safety for any night flying by letting the pilot see what was previously unseen.

We were previously unclear as to what hardware was required to fly NVGs. There are two separate major components: 1.) the NVG "goggles" system, and 2.) having an "NVG-compatible cockpit."

The word "goggles" is really a misnomer with negative connotations. It may make one think of uncomfortable, view limiting, swimming goggles, or maybe the old-fashioned flying goggles—both that fit tight across your face and block peripheral vision.

New-technology NVG "goggles" aren’t like that at all. They don’t even touch your face, but are positioned about 0.75 to 1.25 inches in front of your eyes, held in place by a clever mounting system on a flight helmet. The distance from your eyes to the goggles allows you to look around and under them, increasing your peripheral visual cues. The field of vision of the NVG goggles is about 40°, so a proper scanning technique is taught.

The goggle system we used at Bell was the Northrop Grumman (Litton) M949, a Generation III, civilian system. The useful life of the M949 is 10,000 hours, 2.5 times longer than the earlier AN/PVS-5 goggles.

The goggle system is completely independent of the aircraft’s electrical power, operating for ten to 22 hours from a pair of AA alkaline batteries.

The batteries are in a plastic dual pack that is Velcroed to the back of the flight helmet. The battery pack holds two sets of two AA batteries (one pair is a backup) and has a three-position to let you select which side you want to use. A single wire connects the batteries to the helmet mount in front.

A small, unobtrusive red blinking light above the goggles warns of low battery power. With a flip of the battery selector switch, the backup batteries give you another ten to 22 hours of use. (The battery selector switch is also handy to the NVG instructor to reach and flip to "off" for simulated goggle failure, and Bell’s training curriculum includes preparing for this very rare occurrence.)

The mount firmly holds the goggles in position, yet allows you to pivot them up by hand when not in use. When rotated upward, the battery power to the goggles is disconnected to conserve the batteries. The goggles can be attached and removed from the mount easily for storage or daytime flying, yet are designed to stay attached to the mount up to 15Gs.

The older technology goggles were larger and heavier, often requiring a counter weight to be placed on the back of the helmet. However, counterweights increased the total weight. The new technology goggles weigh only 19 ounces, and the four AA batteries provide an ample counterweight.

The helmet was still comfortable after eight hours of wearing it with the NVG unit attached. Most police, EMS, and SAR pilots already wear flight helmets. Because the goggle system is self-contained, you can keep them operational if you exit the aircraft on the ground, as I did on several occasions to take photos.

I noticed no eyestrain as a result of the NVG flights. Flying with NVGs is less stressful than flying unaided, particularly with the GEN III technology.

Since most NVG operations have a pool of goggles, rather than each of the pilots having their own, a brief adjustment and focusing procedure is accomplished as part of nighttime prestart check. It takes less than a minute to get them adjusted just the way you want them. If you wear glasses, you can still wear them with the new NVG goggles.

Unlike binoculars, however, you don’t look through NVG goggles, you look into them. Think of it as looking into miniature display screens at the back end of the goggles. Ambient light enters the front of the NVG goggles and is multiplied 2,000 to 3,000 times, then converted into green-tinted, monochromatic images on the screen.

NVG-compatible cockpit

We were under the misconception that the cockpit had to be lit in such a way as to allow the pilot to see and read the instruments through the NVG goggles. This used to be the case in early technology NVG goggles.

Because of focusing problems, in two-pilot aircraft the co-pilot would focus his goggles for close work to handle the inside of the aircraft (instruments, radios, maps), while the pilot would focus to infinity for distance and handle the flying. The other bad choice was for the pilot to focus one eye for close work inside, and the other eye for outside flying distance. I can understand why accidents occurred during the early days of NVGs, especially in low-level and formation flying.

With new-technology NVGs, the smaller off-the-face goggles are focused for flying and the crew simply looks below or around the goggles to adjust radios and to see the instruments and maps. Yet, the interior lights must not interfere with the NVGs. In some missions, such as EMS, even aft cabin auxiliary lighting must be made NVG compatible.

The Bell 206 JetRanger we flew has a low-cost STC’d night vision-compatible lighting system from Texas Aviation Services of Fort Worth, Texas. This lighting system, called the Spider Illumination System, uses the latest ANVIS-white light color, rather than the older technology blue-green lights.

According to Tim Woodard, vice president, Texas Aviation Services, "the Spider system costs about one-third of traditional NVG compatible cockpits." To learn more, go to www.texasaviationservices.com.

Ground school

We found the ground training to be informative and well presented. Numerous photos, graphs, and charts helped in understanding the smoke-and-mirrors of being able to see in the dark. The eight hours of afternoon classroom time was paced to match the night flying schedule.

Topics covered in the ground school included an introduction to the NVG hardware and system including NVG preflight adjustments, emergency procedures and limitations, physiological considerations, night terrain interpretation, and night mission planning. Also included was "blind" cockpit training so you can be familiar with the general location of critical system switches and circuit breakers.

Through the years, we have been to numerous JetRanger, LongRanger, and 407 flight training classes, both initial transition and recurrent courses, at Bell’s Training Academy. The syllabus of required maneuvers in this course seems identical to the day/VFR pilot training courses—except all of the 7.5 hours were done at night and under the NVG goggles.

The NVG course’s detailed maneuver guide listed the training object, performance requirements, common errors, and special NVG considerations.

Bell considers its NVG course to be unique, in that it covers all emergency procedures that are normally taught in daylight flying. Detecting visual cues, when looking through a 40° field of vision in 2-D instead of 3-D, is different than in daytime flying. Our training periods were in accordance with the maneuver guide.

Included were all the normal tasks for preflight, engine start, run-up and before takeoff. The NVG goggles were put on and adjusted before takeoff. Hovering required scanning to pick up more visual cues to keep stationary. Normal and steep approaches and running landings were procedurally the same as daytime.

We performed numerous touchdown night autorotations from all flight regimes—hover, takeoff, landing, straight-in, 180°, and even a hover out of ground effect (HOGE) at the top of the H/V curve, all under the NVGs. In addition, a variety of emergency landing procedures were performed, including hydraulics failure, left and right stuck pedal, and go-arounds.

Since inadvertent flight into instrument meteorological conditions (IMC) is more likely at night, we performed inadvertent weather recovery procedures, including basic instrument flying (with the goggles switched off) and then a flight to a nearby airport to shoot an ILS approach. Other important maneuvers were "mission realistic"—confined area takeoffs and landings, slope operations, wire obstacles, and even low-altitude hover in a simulated search pattern.

NVG flying confirms the age-old truisms: "The helicopter doesn’t know it is dark" and "black air provides lift." The difference with NVGs is that the pilot can now see what was previously unseen.

At the conclusion of Bell’s new NVG course, my son Shannon and I were convinced that we gained NVG competence.

With this new technology, special skills must be developed and "best practices" understood. Bell’s new NVG course helps make NVG pilots safer and aviation organizations more effective in carrying out their nighttime missions.