Wednesday, October 1, 2014
NVGs: Getting Certified
NVGs are becoming critical components to modern airframes. What does it take to get your NVG certified?
|Panel of an NVG modified Bell 407 operated by ALERT Air Ambulance, Kalispell, Montana. Photo by R&W|
The use of NVGs is clearly a trickle-down technology originating with the military. But there is a distinct difference from certain military applications that should not be overlooked. The military uses NVGs to achieve flight when it would be otherwise impossible, such as during Nap of the Earth flying. With civilian use of NVGs, goggles are to be used only when conducting visual flight operations as defined by the current regulations. It will not enable any mode of flight that cannot be flown visually within the framework of the existing rules. This doesn’t mean that NVGs can’t help you fly safer or with more precision. It means that legally speaking, NVGs do not make flight possible. All operations must meet the requirements of the regulations as if NVGs were not used.
|Checking out the fit of a new panel before making the final adjustments and installation. Photo by R&W|
The NVIS currently consists of five elements: NVGs, interior and exterior lighting aircraft modifications, cockpit windows, crew station design and components, and a radar altimeter. Each of these areas must meet a minimum level of performance, as outlined by the MOPS. Adding such a system to your existing aircraft begins with applying for a Supplemental Type Certificate (STC). Companies such as Aero Dynamix, Aviation Specialties Unlimited, and Rebtech specialize in NVIS installations and continued maintenance, and hold STCs for numerous aircraft models. For your STC to be issued, your goggles must satisfy the specifications described in Technical Standard Order TSO C-164, your aircraft lighting and cockpit must be modified without invalidating any of the already existing rotorcraft certification requirements listed in FAR parts 27 and 29, and it must possess the proper required instruments to complete the system. Selecting an FAA-approved NVIS modification to be installed through a reputable vendor will ensure that each of the five elements mentioned will be in conformity.
|CNC machines, such as the one shown here, allow for cuts to highly precise specifications for panel modifications so that no unwanted light will leak out. Photo by R&W|
What happens next depends on the type of operation you have. If you fly Part 135, consult FAA Order 8900.1 in the FAA Inspector’s Handbook. Volume 4, Chapter 7, Section 4 outlines what additional items will be required for any Part 135 operator to gain approval to operate with night vision goggles. In it, you will find references to the three RTCA documents mentioned above.
|High‐tech machines such as this spectroradiometer owned by Aerodynamix measure the color and radiance of light being emitted at every frequency – visible as well as infrared – in order to determine how bright that light will appear under the goggles. Photo by R&W|
Once your proposed procedures and program changes are evaluated, observed, and found to be effective, you will be issued two operation specifications, or more specifically, OpSpec A050, Helicopter Night Vision Goggle Operations (HNVGO), and OpSpec D093, Helicopter Night Vision Goggle Operations (HNVGO) Maintenance Program. These two OpSpecs, along with your aircraft’s STC approval, will allow you to conduct legal helicopter night vision goggle operations! Wow. Piece of cake, right?
If your operation falls under the rules of FAR part 91, you should [as of this writing] consult Notice 8900.237 for details authorizing the use of NVIS. Simply put, the notice says that you do not need operational approval to operate night vision goggles under Part 91, unless you are operating under part 91K, or under a Letter of Agreement. However, your NVIS installation must still be FAA-approved, and the goggles used must be compatible with the NVIS installation. Also, all pilots and operators, including those operating under part 91, must comply with the applicable NVG regulatory requirements in 14 CFR parts 61 and 91. As often happens in the minutia of regulation, this brings up a possible paradox. Under part 91, we are required to follow the instructions in the Pilot’s Operating Handbook of our aircraft. As was mentioned earlier, the flight manual supplement that accompanies every NVIS STC states you must have FAA approval to operate using NVGs. Although Notice 8900.237 states the contrary, it would be in your best interest to contact your local Flight Standards District Office (FSDO) and let them know you are conducting NVG operations just to be sure. Notice 8900.237 is set to be canceled on September 19, 2014, at which time it should be incorporated into Order 8900.1.
|Left to right: ALERT Air Ambulance Director of Maintenance Brett Reilly discusses tweaks to the layout of his panel with Mike Guinn of Aerodynamix. Photo by R&W|
|Panel elements taped off and ready for another coat of precisely applied paint dispensed by a robotic paint arm. Photo by R&W|
There are no specified requirements for NVIS in public use aircraft. However, if you are flying NVG operations in a public use capacity, it would be a wise investment to modify your aircraft using an approved STC. The cost may be offset by lower insurance premiums, and certainly cannot be compared to the cost of an incident or accident involving NVGs.
Once your NVIS is up and running, what will it take to maintain it? The successful implementation of NVGs into any operation will only be as good as its ongoing maintenance and training programs. Instructions for continued airworthiness, as well as unscheduled maintenance issues, can vary with each type of NVIS. The unique operational requirements of flying in the civil environment dictate that training be tailor-made to suit it. These issues and more will be explored in the next segment of this multipart night vision goggle series.