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[BT~Teacher]

Since we've entered the Vietnam era and beyond in Il-2, I was thinking if it's possible to add nightvision? Maybe in a form of a filter?
Could really spice up some 60's and 70's night ops.

[CWMV]

What sort of NVG's were in use in 'Nam?
Starlight scopes were way too big for use by aviators

[BT~Teacher]

What sort of NVG's were in use in 'Nam?
Starlight scopes were way too big for use by aviators

Not sure.
But historical or not, they would make night missions with jets much more enjoyable and possible.

[crazyflak]

But historical or not,

uh? sorry, but *if* it is not going to be historical why not requesting nightvision to make WWI missions more interesting? 

(it just wouldn't make any sense, right? better request an Apache Helicopter ).

Since you don't even know if it is historical, I guess it is useless to expect some technical data that -by request guidelines- is mandatory?

[BT~Teacher]

But historical or not,

uh? sorry, but *if* it is not going to be historical why not requesting nightvision to make WWI missions more interesting? 

(it just wouldn't make any sense, right? better request an Apache Helicopter ).

Since you don't even know if it is historical, I guess it is useless to expect some technical data that -by request guidelines- is mandatory?

Would be fun to shoot down Red Baron with an Amraam in zero visibility conditions.

Anyways, since we have so many "what if stuff" flying around, what harm would a NVG option add?

[Kazegami]

Would be fun to shoot down Red Baron with an Amraam in zero visibility conditions.

Well we'd first need an AMRAAM 

[BT~Tarik]

http://www.davi.ws/avionics/TheAvionicsHandbook_Cap_7.pdf

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In 1971 the USAF began limited use of the SU-50 Electronic Binoculars. In 1973 the Army adopted the
Gen II AN/PVS-5 as an “interim” NVG solution for aviators, although there were known deficiencies in
low-light-level performance, weight, visual facemask obstruction, and refocusing (due to incompatibility
with cockpit lighting systems). The
aviator’s
night vision imaging system (ANVIS) was the first NVG
developed specifically to meet the visual needs of the aviator. The NV&EOL started ANVIS development
in 1976 utilizing third-generation image intensifier technology and requiring high-performance, lightweight,
and improved reliability and maintainability.


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An
image intensifier
is an electronic device that amplifies light energy. Light energy, photons, enter into
the device through the objective lens and are focused onto a photocathode detector that is receptive
to both visible and near-infrared radiation. Generation III devices use gallium arsenide as the detector.
Due to the photoelectric effect, the photons striking the photocathode emit a current of electrons. Because the emitted electrons scatter in random directions, a myriad of parallel tubes (channels) is required to
provide separation and direction of the electron current to assure that the final image will have sharp
resolution. Each channel amplifier is microscopic — about 15m in diameter. A million or so microchannels
are bundled in a wafer-shaped array about the diameter of a quarter. The wafer is called a
microchannel plate (MCP). The thickness of the MCP, which is the length of the channels, is about 0.25
in. Each channel is an electric amplifier. A bias potential of about 1000 V is established along the tube, and each electron produced by the photoelectric effect accelerates through the tube toward the anode.
When an electron strikes other electrons in the coated channel, they are knocked free and continue down
the tube hitting other electrons in a cascade effect. The result of this multiplication of electrons is a greatly
amplified signal. The amplified stream of electrons finally hits a phosphor-type fluorescent screen which,
in turn, emits a large number of photons creating an image.
The microchannel plate is a solid-state light amplifier. The intensity of the image is a product of the
original signal strength (i.e., the number of photons in the night scene) and the amplification gain within
the channel. The fine resolution of the total image is a product of the pixel size from the MCP array and
the focusing optics.
The manufacture of MCPs requires complex processes which are dependent on a two-draw glass
reduction technique. A concentric tube of an outer feed glass and an inner core glass is drawn into a
fine fiber about 1 mm in diameter. Then a bundle of thousands of the fibers is draw to form a multiple
fiber about 50 mm in diameter. The core glass is etched out leaving a matrix of hollow glass tubes.
Wafer sections are sliced, and the wafers are plated with the metallic coatings necessary for the signal
amplification.
The finished product is an NVG which contains an MCP packaged inside an optical housing. The
housing will contain objective lens and eyepieces appropriate for the NVG’s utilization. For aviators using
the NVG for pilotage, a one-to-one magnification is required. The pilot’s perceived NVG image of the
outside world must be equal to the actual size of the unaided-eye image of the outside real world to
provide natural motion and depth perception. The image is displayed to the observer on an energized
viewing screen at about 1 footLambert (fL). Screens may be the P20 or P25 phosphors. The light
amplification may be 2000 or more, and to prevent phosphor damage, an automatic gain control (AGC)
circuit limits the gain in high ambient conditions.



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7.2.2 Amplification of the Night Scene
Second-generation image intensifiers utilize multi-alkali photocathodes that are sensitive in the visible
and near-IR bandwidth of 400–900 nm. Gen II utilization is generally limited to a minimum of quartermoon
or clear sky illumination.
Third-generation image intensifiers utilize galium arsenide (GaAs) photocathodes which are more
sensitive than Gen II and have a bandwidth of 600–900 nm. Gen III NVIS can be used in starlight and
overcast conditions

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7.2.4 Integration into Aircraft
The integration of NVIS into an aircraft crew station usually requires very little modification with respect
to the crew compartment space (volume). The primary aircraft requirements are
1. Adequate helmet and NVIS motion envelope;
2. Acceptable visual fields of view (FOV) and windshield transparency in the NVIS range;
3. Compatible cockpit lighting and displays;
4. Compatible interior (cabin) and exterior lighting.
The alerting quality of warning/caution/advisory color coding can be diminished with NVIS compatible
(Class A) cockpit lighting. Audio or voice warning messages may be considered to augment the alerting
characteristics.
The NVIS is normally a self-contained standalone sensor that is powered by small batteries. The cost of
a typical NVIS unit is $10,000, whereas the cost of an aircraft-mounted IR sensor system is 10 to 20 times
that amount. The integration of an NVG HUD requires more modification to the aircraft than the NVIS.
Incorporation of NVIS produces some advantages and some disadvantages for the aircraft and missions.
NVIS advantages usually outweigh disadvantages
. The advantages are
• NVIS allows 24-hour VFR operations (pilots say: “I’d rather fly with them.”)
• Enhanced situation awareness; pilots can see the terrain.
The disadvantages are
• Limited instantaneous FOV which requires deliberate head movement;
• Neck strain and fatigue (due to increased helmet weight & increased head movement);
• Cost of equipment (NVIS

compatible lighting);
• Pilot training; currency; proficiency;
• Not useful in IMC weather or fog;
• Safety — if there is inadequate training or overexpectations of system capability.
There are known limitations of the NVIS imposed by the limited FOV. Training is required to emphasize
the required head motion scanning to compensate for the FOV. Depth perception is sometimes reported
as a major deficiency, although it is most likely that inadequate motion perception cues due to limited
peripheral vision are a contributor to this perception.
Military training programs have been implemented to exploit the capabilities of the NVIS sensor for
various types of covert missions, and to improve safety and situation awareness. Curricula have been
developed “…
to assure that there is an appropriate balance of training realism and flight safety
.” Training
programs include visual aids, laboratory, and simulation to cover:
• Theory of operation;
• FOV, FOR, adjustment;
• Moon, weather, ambient conditions;
• Different visual scans, head motion.[/quote]

[code]7.3 Applications and Examples
7.3.1 Gen III and AN/AVS-6 ANVIS
To aid night flying, in the 1980s the Army developed the Aviator’s Night Vision Imaging System (ANVIS)
which is a third-generation (Gen III) NVG. The ANVIS is designated as AN/AVS-6. ANVIS is lightweight
(a little over 1 lb) and mounts on the pilot’s helmet. The 25-mm eye relief allows the pilot to see around
the eyepieces for viewing the instruments in the cockpit. The Gen III response characteristics are more
sensitive than Gen II and the spectral range covers 600 to 900 nm. This spectral range takes advantage of the night sky illumination in the red and IR. Luminance gain is 2000 or greater. The FOV is 40° circular
and the resolution is about 1 cy/mr. The total weight is 1.2 to 1.3 lb. There are several adjustment features on the ANVIS to accommodate each pilot’s needs:
• Inter-ocular adjustment
• Tilt adjustment
• Vertical adjustment
• Eye relief (horizontal) adjustment
• Focus adjustment
• Diopter adjustment
The pilot can also flip up the ANVIS to a “helmet stow” position. The mount has a break-away feature
in case of a high
g
load or crash.
Early production models of ANVIS units produced system luminance gains of 2000 fL/fL. With
improvements in manufacturing techniques and yields, and with increased photocathode sensitivities,
newer units have system gains of over 5000. The Army procured large lot quantities of AN/AVS-6
through “omnibus” purchase orders. Omni IV and Omni V AN/AVS-6 have system luminance gains of
5500. The luminance gains of the intensifiers may be 10,000 to 70,000, depending on the ambient
illumination being amplified, but with optics and system throughput losses, the overall system gains
are 5000

. Presently, the two major suppliers in the U.S. for AN/AVS-6 are ITT and Litton, and the
Army splits the procurement of the Omni lots. Adaptations and improved versions of the AN/AVS-6
include the AN/AVS-8 with a 45

FOV, and the AN/AVS-9 which has a front-mounted battery to allow
use in ejection seats. The AN/AVS-9 also has a “leaky green” sensitivity to allow viewing of the HUD
symbology.

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7.3.2 Gen II and AN/PVS-5 NVG
The generation II AN/PVS-5 is outdated and is not now recommended for aviators. The AN/PVS-5 is
discussed here because it was the most common device allowing night flying with NVG aided vision. The
AN/PVS-5A provided Army ground forces with enhanced night vision capability. Later, pilots used the
NVG to fly helicopters. Tests indicated that pilots using NVG could fly lower and faster than pilots without
NVG, and concluded that NVG provided considerable improvement over unaided, night-adapted vision. The AN/PVS-5A weighs 2 lbs and has a full face mask. Wearing these NVG requires the pilot to make
all visual observations via the NVG, including cockpit instrument scanning. The pilot must move his
head and refocus the lens to read the instruments. Annoyance, discomfort, and fatigue result from these
restrictions. The spectral range of the Gen II NVG is from 350 to 900 nm which includes the entire visual spectrum
(380–760) plus some near-IR coverage. Most 1970s cockpits had red incandescent lamp lighting which
had large red and IR emissions. The NVG’s automatic gain control (AGC) shuts down the NVG in the
presence of large amounts of radiant energy in the goggles’ range. Therefore, the use of Gen II NVG
requires that all visible lighting must be reduced below the pilot’s visual threshold in order that the
lighting does not degrade the NVG operation. Commonly, this is accomplished by extinguishing the
lights or using a “superdim” setting. Under these conditions, crew members without NVG cannot read
the cockpit instruments. Crew members with NVG must refocus from outside viewing to read the
instruments. Research in the U.S. and U.K. on shared-aperatures and shared-lens attempted to provide
viewing of the cockpit instruments with the NVG. Modifications to the face mask to provide peripheral
and in-cockpit vision produced the “cut-away” mask.
The utilization of AN/PVS-5 NVG in aviation was controversial. The incorporation of NVG into
aviation somewhat repeated the development of aviation itself, with a period of trial and error incorporation,
sometimes with inadequate or inappropriate equipment, producing some pioneering breakthroughs
and some accidents. In the 1980s there were nighttime accidents often involving NVGs. The
Orange County Register
published a lengthy investigative article because several of the helicopter crashes
took place within the county.
14
A congressional hearing was convened to review the safety and appropriateness
of NVGs in military helicopters.
15
The necessity of NVGs for night flight operations was
confirmed along with an emphasis on better equipment and training. A review of AN/PVS-5 and
AN/AVS-6 testing concluded both were acceptable.
16
Since that time, AN/AVS-6 ANVIS has become the
preferred device for aviators.

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7.3.3 Cat’s Eyes
The “Cat’s Eye” is a Type II (projected image) Gen III NVIS made by GEC-Marconi, and [b]is standard
in the AV-8 series of Harrier aircraft[/b]. The weight is slightly over 1 lb. The two optical combiner lenses
have the image displayed for out-of-the-cockpit viewing. The combiner has see-through capability
to view the aircraft’s HUD. When the pilot is looking at the HUD, the imagery is automatically
turned off to allow visibility of the HUD symbology. The combiner glass see-through transmission is
30%. The Cat’s Eye has a 25-mm eye relief to allow look-under for cockpit instrument viewing.

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7.3.4 NVG HUD
Systems termed “NVG HUD” have been produced that add head-up display (HUD) symbology onto the
displayed night vision imagery provided by the NVG. Usually the HUD portion is a CRT image projected
onto a combiner glass mounted in front of one of the NVG objective lens. The symbology displayed is
aircraft information (attitude, altitude, airspeed, navigation data, etc.) that is generated in a processor
box integrated to the aircraft systems.
There is way more in the pdf, for those who are interested.

Did anybody ask for technical data... 

 

[crazyflak]

Anyways, since we have so many "what if stuff" flying around, what harm would a NVG option add?

You have a point

[Telmo]

I know that Tiger tank had last night visions. They had small roles in the last day in war but they had a superiority against one!
So I think that with aerial combat could have been the same. The Wehrmacht had the first prototypes of night vision . She had built a dozen for his Sturmgewehr 44.

I apologize for something I have not had the courage to read in your article MilanTarik, I hope it was not written on it.

[BT~Tarik]

Dont worry, the article is about nightvision for airplanes  And I definitely understand that you didnt read it, its quite long !