The Latest in Night Eyes: White Phosphor NVGs

 - September 21, 2015, 8:16 AM
White phosphor displays for night-vision goggles provide more contrast and more visual acuity than their green counterparts, according to ASU, which makes the white display.

White phosphor night-vision goggles (NVG) provide more detail and cause less eye strain than the traditional green phosphor now dominating the industry, advocates for their use claimed at the recent annual NightCon convention in Dallas.

“Almost 25 years ago the Department of Defense (DOD) predicted the demise of light-amplifying night-vision goggles. That said, their vision was that NVG technology would be outmoded before the end of the 20th century,” said Aviation Specialties Unlimited (ASU) president Jim Winkel. “They predicted everything would go to thermal.” But war intervened, beginning with the first Gulf War in the 1990s, and suddenly the military was ordering thousands of units. “That allowed companies to make an investment in NVG technology, which still applies today,” said Winkel.

With military money pouring in, ASU and other NVG makers found new ways to make technological advances, keeping the technology alive over the past 20 years or so. At last year’s NBAA Convention, ASU announced one such innovation: white phosphor displays for night-vision goggles. The white phosphor provides a significant advantage over green, said ASU’s Dr. Joe Estrera: “There’s more information available to the eye with white phosphor than with green,” Estrera explained. “In fact, green is one of the colors embedded in white because white is a combination of all colors. So instead of providing information to the brain through just one set of receptors [green], [white phosphor technology] provides much more information to all the visual receptors in the brain.”

In addition, white phosphor has the same response command as green while providing more contrast and more visual acuity. And while green phosphor targets just one set of receptors in the eye’s complex makeup, white targets all receptors. The result, said Estrera, is much less eye strain. (Most pilots who have flown with night-vision goggles report that just a couple of hours of use will lead to “pink or brown vision,” which is what happens when the receptors sensitive to green light have been oversaturated.)

Although the white phosphor NVG technology was introduced nearly a year ago, most aircraft have not yet been approved for their use. Still, Winkel is bullish on the product.

“We’ve had an overwhelming response to white phosphor,” he said. “Seventy percent of those who’ve seen it want it.” In fact, he said, “The first reaction most people have when we demo them is ‘Wow!’”

But that is not a universal opinion.

Steven Todd Whaley flies an AS350BA AStar on night missions for the Flagler County Fire Department in Florida. He became a night-vision instructor and expects to achieve Part 135 NVG certification soon.

When he read about the white phosphor innovation, he immediately wanted a first-hand demonstration. He tried the displays and reported, “I couldn’t tell a wonderful difference.” Whaley’s supervisor tried them as well. They compared notes. Together, they decided white phosphor was not for them. The primary driver in the decision was the fact that the devices are not STC’d for the company’s aircraft. However, “There were some other things that we think can be improved.”

FAA Regs Need To Catch Up                                                                                             

In the regulatory realm it has always been a difficult for the night-vision industry and the FAA to reach consensus. The FAA has often been accused of feeling its way along in the dark when it comes to approving night-vision technology, said conference organizer Lyn Burks, publisher of Rotorcraft Pro Magazine. “But in part, because of this conference, we’ve been able to change that. Now, the FAA is an active advocate of night-vision technology,” Burks said. Still, at this year’s NightCon, the agency figuratively shook a finger at Part 61 NVG instructors who teach and certify other instructors.

They can’t.

In an advisory dated Aug. 21, 2015, the FAA directed that only the FAA can do that. It also requires new language on the endorsement authorizing NVG instructors to read: “This endorsement does not provide the authority to endorse another flight instructor as a night-vision-goggle instructor.”

But more change is in the wind, according to Chris Holiday, at the FAA’s ASF-250 Branch.

“I want to head off some of the criticism, feedback, questions and darts, because I write the OpSpecs for the Part 135 operations…When you get to Part 135, people pay you to fly. They have, therefore, a greater expectation of safety. So we’re going to write things different from Part 61. So I really don’t want to hear, ‘Why don’t you guys write the specs the same as you do for Part 61?’ Right now, the OpSpec refers to Part 61.57F for currency. Enjoy it while you’ve got it.”