RV Camping

Night Vision Goggles and Civilian Aviation

2005-12-17T07:51:00.000-08:00

Presented by The Night Vision Store and The OpticStore, authorized ITT Retailers

Night Vision Goggles and Civilian Aviation
The introduction of night vision goggles into civilian aviation imposes additional demands not only on the pilot but on the aircraft itself. In addition to the expense of procuring goggles, the pilot is required to obtain specialized training in goggle utilization. The goggles, although greatly beneficial to the pilot in enhancing his night vision capabilities, do require that the cockpit instruments and displays be modified in order to be compatible with goggle usage.During the past few years, the Federal Aviation Agency (FAA) has been acutely aware of the need for regulations governing the use of goggles and the peripherals, including cockpit illumination. In order to ensure goggles safety by qualified users, the FAA has issued a policy statement in Change 16 to Order 8300.10, Safety Inspector’s Handbook, and in Volume 2, Chapter 1 of the Advisory Circular. In essence, the FAA requires a Supplementary Type Certificate (STC) for "flight deck lighting changes to support night vision goggle use or any approval related to night vision goggles."
In order for the cockpit lighting to be compatible with goggles, the illumination of the cockpit’s instruments and displays will require modification. The modification dictates that the inherent infrared associated with the illumination be eliminated, leaving only visible light available to the pilot or flight crew. This elimination of the infrared permits the goggles to acquire miniscule amounts of infrared available outside of the cockpit. The infrared available from the night sky added by the goggles’ gain control amplification allows for maximum visibility in a nighttime environment.The elimination of the infrared within the cockpit can be accomplished in a number of ways.
Current methods of modification include the use of "open ring" bezels, and the addition of adjunctive lighting systems that may include flood lighting, postlight modification and the modification of the instrument or display itself. Some of these methods require that the cockpit’s integral illumination be eliminated so these secondary lighting alternatives can be effective. Most of these secondary lighting alternatives filter the light source with an NVIS Green filter that not only retards the infrared but changes the lighting color to green. Where postlights are utilized, instruments traditionally are without inherent lighting, so the postlights are thus utilized to provide reflective illumination. In this instance, the postlight can be modified with a filter that retards the infrared but also permits the choice of green or white lighting.
The method of choice is to filter the lighting of the instrument. Currently, there are filters, such as SHADOWS™, that permit modification of the instrument's lighting by removing the instrument's cover glass and replacing it with an infrared retardant filter. This modification process is gradually being accepted by the FAA through the use of "process specifications". There is such a vast assortment of instruments of varying designs and manufacturers that the acquisition of "process specifications" for all instruments becomes a long and arduous task.
An alternative used with great success during the past year in achieving a number of STCs for law enforcement and EMS operators is the use of external filters (SHADOWS SCREENS™) for both instruments and displays. For flight and engine instruments, infrared retardant filters constructed of glass or poly carbon can be employed. The filter selection is predicated on the light source, whether incandescent, florescent, LCD or LED. The filters can be mounted in an aluminum frame and affixed over the instrument’s bezel utilizing the existing mounting screws. The frame for the filter is approximately 0.100" thick, and when placed in position, minimizes any reduction in the cone of visibility. Mechanical or electrical modification to the cockpit or airframe is not required, thus eliminating costly installation charges. In addition, the external filter approach allows the instrument to remain generic, thereby eliminating the need for a special maintenance program and retaining the advantages of local repair and/or overhaul.
A distinct advantage of the infrared retardant filter is the utilization of the instrument's inherent white lighting. Retaining the white lighting eliminates the need for repainting dials or warning flags that are generally affected by the saturated green illumination of the NVIS Green filters. In addition, the transmission of visible lighting with the infrared filters is two and half times greater than transmission with green filtered lighting. This advantage is particularly noticeable when a pilot or crew comes off of the goggles to view the instruments. The transmission advantage of the infrared retardant filter permits immediate recognition of the instrument's function without any adjustment of pupil dilation which often occurs with the lower transmission of green lighted instruments.
Those considering the use of infrared retardant filters as the modification method should be forewarned that there are a number of infrared filters available for instrument modification and all of them exhibit some degree of a light blue tint. Some of these filters have a deeper blue coloring than others. The deeper the color, the less transmission is available and the day time visibility can be greatly diminished.
Today, many cockpits include not only electro-mechanical instruments but also solid-state displays. Regardless of the light source of these displays - CRT or active matrix LCDs - a filter solution is available. In numerous instances, the filter is again mounted in a frame and placed directly over the display’s surface. The lighting contractor should provide modification options for consideration. It is imperative that the fit of the frame is such that light leaks from the display are eliminated.
Consulting with your lighting contractor is an important aspect of any modification project. He may offer suggestions based on his previous installation experience so that other options can be discussed and decided upon. These options may include placing and sealing the filter directly to the display’s surface with optical adhesive or by possibly replacing the LRUs existing Polaroid filter with one specifically designed as a compatible replacement. Many of the NAV/COMM displays are modified by replacing the original filter with an infrared retardant filter. It has been found that double filtering (infrared filter over an existing filter provided by the OEM) does not meet the sunlight readability criteria required by the FAA. Replacing the existing filter allows for the modified LRU to be night vision goggle compatibile as well as sunlight readable.
If new or updated accessories are being added to your cockpit, check with your lighting contractor or with the manufacturer of the equipment/system in question to determine if an off-the- shelf version is already available NVG compatible. Many system manufacturers are considering NVG compatible lighting versions of their equipment due to the increasing demands of the military, law enforcement, and EMS operators. An example of a LRU incorporating NVG compatibility is the Avalex monitor. The Avalex monitor incorporates NVG compatibility off the shelf, saving the aircraft user the added expense of having the modification accomplished after the fact.
An area of the modification process that has yet to be clarified for the civilian aviation market is how military specifications for NVG/ANVIS compatibility come into play. If we believe that truth is a moving thing, we must consider that the mil specs that dominate our NVG thinking are good guides, but only that, good guides. In a number of instances, the mil specs provide modification latitude that is acceptable criteria for military programs but are somewhat restrictive for civilian lighting upgrades. Today’s filter and goggle technology has advanced to a point where we are now able to accomplish upgrades that were unheard of only a few years ago or after the mil specs were made public.
The largest area of contention between the dedicated use of the mil specs and today’s technology deals with the filtering of illuminated pushbutton switches and master caution/warn displays. The mil specs have recommended chromaticity coordinates that permit diluted color intensities for the aviation red and amber (yellow) colors. The mil spec color coordinates provides a peach or watermelon color for red and orange/lime color for yellow. Today, there are available various modification methods that allow the maintenance of the original red/red and amber/amber colors that are the mainstay for universal caution and warning alert. In addition, the traditional colors provide superior sunlight readability over the mil spec colors.
Many of the latest modifications have included the need for illuminated panels. Panel upgrades are generally determined by their function and location, with a final determination being made by the FAA for that particular airframe model. Should the panels require NVG compatibility, modification is available in green and white lighting. Consult with your lighting contractor to determine if new panels are required or if the existing panels can be modified. Cost and lead time become an important factors.
It should be remembered that modifications to NVG compatible lighting can be an expensive proposition. To control the costs and to establish exactly what you are contracting for, it is important that you consider the following:
· Is there an STC currently available for my particular model airframe? If not, what are the ramifications?
· Where is the modification accomplished? Can it be done locally?
· How long will it take to accomplish the modification?
· Who and where are the various lighting contractors located?
· Are examples of their work available and who are their customers?
· Is specialized aftermarket support required?
When soliciting a quotation for the NVG lighting modification, the lighting contractor should be totally aware of your cockpit configuration. A survey visit by the lighting contractor often pays dividends in the long run. Digital photos are a great aid in cockpit asset accountability and work towards eliminating any cost increase surprises. In return, the lighting contractor should provide you with an itemized listing of the requirements for modification, not just a total lump sum cost, so that you will be aware of exactly what you are paying for. Remember, it’s your money and your airframe. Be an educated consumer, and don’t be afraid to ask questions
Or visit http://www.nightvisionstore.com and http://www.opticstore.com

HOW NIGHT VISION WORKS

2005-12-01T17:41:00.000-08:00

HOW NIGHT VISION WORKS
Author - C. J. Boedeker - The Night Vision Store & The Opticstore
http://www.nightvisionstore.com/http://www.opticstore.com/
During the history of warfare, operations at night have always been degraded significantly, if not totally avoided. Typically, soldiers fighting at night have had to resort to artificial illumination, e.g., at first fire and later with light sources such as searchlights. The use of light sources on the battlefield had the detrimental result of giving away tactical positions and information about maneuvers. The advent of new technologies initially in the 1950's and continuing into the present time has changed this situation. The engineers and scientists at the Night Vision & Electronic Sensors Directorate (NVESD) have discovered ways to capture available electro-magnetic radiation outside that portion of the spectrum visible to the human eye and have developed equipment to enable the American soldier to fight as well at night as during the day in order to "Own the Night".
Image Intensification: Image intensifiers capture ambient light and amplify it thousands of times by electronic means to display the battlefield to a soldier via a phosphor display such as night vision goggles. This ambient light comes from the stars, moon or sky glow from distant manmade sources, such as cities. A soldier can conduct his combat missions without any active illumination sources using only image intensifiers. The main advantages of image intensifiers as night vision devices are their small size, light weight, low power requirements and low cost. These attributes have enabled image intensifier goggles for head-worn, individual soldier applications and resulted in hundreds of thousands of night vision goggles to be procured by the US Army. Research and development continues today on image intensifiers in the areas of longer wavelength spectral response, higher sensitivity, larger fields of view, increased resolution, advanced displays and image fusion.
Night Vision technology consists of two major types: image intensification (light amplification) and thermal imaging (infrared). Most consumer night vision products are light amplifying devices.
Light amplification technology takes the small amount of light, such as moonlight or starlight, that is in the surrounding area, and converts the light energy (scientists call it photons), into electrical energy (electrons). These electrons pass through a thin disk that's about the size of a quarter and contains over 10 million channels. As the electrons travel through and strike the walls of the channels, thousands more electrons are released. These multiplied electrons then bounce off of a phosphor screen which converts the electrons back into photons and let you see an impressive nighttime view even when it's really dark. All image intensified night vision products on the market today have one thing in common: they produce a green output image. In the night vision world there are generations that reflect the level of technology used. The higher the generation, the more sophisticated the night vision technology.
Generation 0 - The earliest (1950's) night vision products were based on image conversion, rather than intensification. They required a source of invisible infrared (IR) light mounted on or near the device to illuminate the target area.
Generation 1 - The "starlight scopes" of the 1960's (Vietnam Era) have three image intensifier tubes connected in a series. These systems are larger and heavier than Gen 2 and Gen 3. The Gen 1 image is clear at the center but may be distorted around the edges. (Low-cost Gen 1 imports are often mislabeled as a higher generation.
Generation 2 - The microchannel plate (MCP) electron multiplier prompted Gen 2 development in the 1970s. The "gain" provided by the MCP eliminated the need for back-to-back tubes - thereby improving size and image quality. The MCP enabled development of hand held and helmet mounted goggles.
Generation 3 - Two major advancements characterized development of Gen 3 in the late 1970s and early 1980s: the gallium arsenide (GaAs) photocathode and the ion-barrier film on the MCP. The GaAs photocathode enabled detection of objects at greater distances under much darker conditions. The ion-barrier film increased the operational life of the tube from 2000 hours (Gen 2) to 10,000 (Gen 3), as demonstrated by actual testing and not extrapolation.
Thermal Imaging:
Most objects in natural scenes, as well as human beings and manmade objects emit electro-magnetic radiation in the form of heat. Thermal imagers or infrared viewers (also known as FLIRs) gather the infrared radiation and form an electronic image for the soldier. Since they do not rely on reflected ambient light, thermal imagers are totally light-level independent. They also have significant penetration capabilities through obscurants such as fogs, hazes, and conventional battlefield smokes. There are two varieties of thermal imaging systems: cooled and uncooled. Cooled thermal imaging requires cryogenic cooling. Lower performing uncooled thermal imaging systems require no detector cooling but have sufficient performance to provide the low to medium performance required by individual soldier sights, infantry vehicles, navigation, robotics and missile seekers. Present research and development in cooled thermal imaging are pursuing multi-spectral imaging, improved sensitivity and resolution, and embedded signal processing to aid the soldier in target acquisition missions. Current uncooled research is directed at smaller size packages and power consumption with lower cost and increased sensitivity, resolution and field of view. Small, palm-sized uncooled thermal imagers are now available.
About the Author
C. J. Boedeker provides Night Vision equipment and Consulting for both Professional and Hobbyist applications. He can be reached at http://www.nightvisionstore.com/ or http://www.opticstore.com/

Camping In A RV For Fun And Pleasure

2005-11-28T07:37:00.000-08:00

Camping In A RV For Fun And Pleasure by Sintilia Miecevole
Presented by The Night Vision Store and The OpticStore, authorized ATN Retailers
Camping for most people means a tent and sleeping on a mat on the ground. If that doesn't really appeal to you, then camping in an RV is what you need. It is the ultimate camping adventure.
RV's come in many sizes and shapes. They start with campers that fit in the back of a pickup truck. These can have full kitchens, beds, a shower and toilet in them.
Next there are van conversions called Class B motorhomes that are basically a cargo van converted into a camping vehicle. These can have a raised roof for more head room. They also contain the same amenities as the truck camper.
Next up is the Class C motorhome. The front end looks like a pickup truck, but the similarity ends there. There is a sleeper extension over the cab and the back end looks like any motorhome you are probably familiar with. Basically a cargo box with windows, but much prettier. The Class C has all the amenities of home. A kitchen, bathroom, bedroom and living room. You could live in a Class C.
The next step us is the Class A motorhome. This is roomiest of all motorized RVs. These motorhomes are like a mini one bedroom apartment. They are fully self contained. From the queen sized bed to the dinette that seats four people you find luxury. A refrigerator and stove are complimented by a microwave oven. You might even have an ice maker capable of making over 20 pounds of ice a day. Party ready!
If that weren't enough choices, there are still the trailers. First is the travel trailer you can pull behind a larger sedan or SUV. Then the 5th wheel trailer that hooks into the back of a pickup truck. Both of these trailers are equally as luxuriant as the best motorhome. An advantage is they cost a lot less.
You can buy new or used. Whichever way you choose, you should do a lot of research on the internet first. Learn all you can about RVing. There are RV forums that you can find by doing a search in your favorite search engine.
When you decide that an RV might be for you, attend an RV show or two. There are major RV shows at fairgrounds and stadiums where many dealers and vendors are selling every type of RV there is. There are also local RV shows usually put on by one or two dealers to show and sell some of their inventory.
If you really are not sure you would like to spend $40,000 or $250,000 on a hobby you are not sure you would like, buy a used RV. You can get into RVing in a 34 foot used Class A motorhome for under $10,000.
The older and larger the motorhome the less fuel efficient it will be. You may get 5 to 7 miles per gallon on many older motorhomes. 7-9 mpg is realistic for mid 1990's motorhomes and up to 12 miles a gallon on new ones.
Camping in an RV is a fun adventure awaiting you and your family.
About the Author
Sintilia Miecevole loves camping and now has a site http://www.uncampingcar.com for you to enjoy. Check out http://www.uncampingcar.com and find information from campsites, trailers, supplies, rvs and reservations to hiking, equipment and much more.
Or visit http://www.nightvisionstore.com and http://www.opticstore.com