Night Vision Goggles for Helicopter Pilots

By Mike Becker

Night Vision Goggles for Helicopter Pilots is written by Captain Mike Becker, one of Australia's most

experienced helicopter instructors. With over 16,000 helicopter flight hours and recipient of the "Captain John

Ashton Award for Flight Standards and Aviation Safety" by the Guild of Air Pilots and Air Navigators of

London, Mik

• Language: English
• Publisher: Becker Helicopter Services Pty Ltd
• Release date: Apr 21, 2022
• ISBN: 9781876770129

Mike Becker

Mike Becker is one of Australia's most experienced helicopter instructors, with over 16,000 hours of rotary-wing flight experience. His career has taken him from the mountains in New Zealand to the outback of Australia and the jungles of Papua New Guinea. He has also worked in the United States, Italy and Borneo.He has flown a range of helicopter types - the Robinson R22, Robinson R44, Bell 47, Hughes 269, Hughes 500, Bell 206, Bell 427, Bell 212, EC120, Dragon Fly, Brantley B2B, Enstrom EF28, Sikorsky S62A, Hiller H12ET, Aerospatial AS350, Agusta 109E Power, Agusta 109S Grand, and the Agusta 119 Koala.He is experienced in a comprehensive range of helicopter operations, including high altitude, remote area operations, mustering, firefighting, tourism, sling load operations, specialised long-line operations, search and rescue, and Night Vision Goggles operations.Mike is a Grade One Flight Instructor and Flight Examiner who holds an Australian Air Transport Pilots Licence (Helicopter) and an Australian Commercial Pilots Licence (Fixed Wing).Mike is the Chief Pilot and Head of Training for his own business Becker Helicopters, in Australia. He, and his wife Jan, established Becker Helicopters in 1997 with one Bell 47 and have grown the company through a love of helicopters, hard work, and determination.Mike is the recipient of many awards, including the "Captain John Ashton Award for Flight Standards and Aviation Safety" by the Guild of Air Pilots and Air Navigators of London, which was awarded in recognition of over 18,000 accident-free flight training hours at Becker Helicopters. Mike has also authored "Mike Becker's Helicopter Handbook", first published in 1986, and a range of theory books and instructional videos.

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About this Publication

Title:

Night Vision Goggles

Series:

For Helicopter Pilots

Edition:

First published 2011, Third Edition, January 2022

Principal Author:

Mike Becker, ATPL(H), FIR, FER, Diploma (Training and Assessment)

Editor:

Bev Austen, BTech(CompSt), MEd(DTL)

Copyright

Copyright © 2022 Becker Helicopter Services Pty Ltd

Photos and Illustrations

Most photos and illustrations in this document have been sourced from Becker Helicopter Services Pty Ltd.  The remainder is taken from the internet from various sources; Every effort has been made to ensure images with Creative Commons Licences have been used and/or appropriate attribution provided. 

Disclaimer

Nothing in this text supersedes any operational documents issued by any civil aviation authority or regulatory body, aircraft, engine, and avionics manufacturers or the operators of aircraft throughout the world. No responsibility is taken for the interpretation and application of the information contained in this document. Managing the safety of the aircraft is the sole responsibility of the pilot-in-command.

Every possible effort has been made to establish the accuracy of the information contained in this book; however, the author, Becker Helicopter Services Pty Ltd, accept no responsibility for errors or omissions.

The Publisher and the Author make no representations or warranties for the accuracy or completeness of the contents of this work and expressly disclaim all warranties, including without limitation warranties of fitness for a particular purpose.  No warranty may be created or extended by sales or promotional materials.  The advice and strategies contained herein may not be suitable for every situation.  This work is sold with the understanding that the author is not engaged in rendering legal, accounting, or other professional services.  If professional assistance is required, the services of a competent professional person should be sought.  Neither the Publisher nor the Author shall be liable for damages arising therefrom. 

The fact that an organisation or website is referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organisation or website may provide or recommendations it may make.  Further, readers should be aware that internet websites listed in this work may have changed or disappeared between when this work was written and when it is read.

Contents

About this Publication

Contents

About this Book

About the Author

The History of Light

Electricity

The Intensifier Tube

Summary

Science of Light

A Star: The Source of Light

Photons

Light Spectrum

Speed of Light

Colours of the Spectrum

White

Black

Grey

Tints, Shades, and Tones

Infrared Light

Atoms, Energy and Heat

Thermal Imaging

Night Vision Devices (NVDs)

Light Terminology

Candlepower

Foot-candle

Lumen or LUX

Newton's Inverse Square Law

Radiance

Illuminance

Luminance

Summary of Light Terminology

What is a Laser

Laser Classification System

Laser Warning and Classification Labels

Laser Type and Wavelength

Components of the NVG

Binocular Housings

Lenses

Convex Lens

Convex Lens Image Inversion

Concave Lens

Planar Lens

Compound Lens

NVG Objective Focal Adjustment

NVG Filters

Light Intensity Filter (LIF)

Class A and B Cockpits

Class A and B Filters

Modified Class B Filters

Current NVG Requirements

NVG Eyepiece and Dioptric Focus Lens

Intensifier Tube

Gain

Tube Gain

System Gain

MTTF (Mean Time To Failure)

Photocathode

Geometric Distortion

Making a Photocathode for NVG

Photosensitivity

Generational Change

Vacuum Chamber

Microchannel Plate

Making a Microchannel Plate

Ion Barrier Film

Phosphor Screen

What are Phosphors?

Making a Phosphor Screen

Fibre Optic Inverter

What is Fibre Optics?

Distortion

S-Distortion

Sheer Distortion

Electrical Supply

Anode and Cathode

Controlling the Amount of Light

Blooming

Halo Effect

Bright Source Protection (BSP)

Automatic Brightness Control (ABC)

Autogain

Autogating

Operational Defects

Unacceptable Defects

Shading

Edge Glow

Emission Points

Flashing, Flickering or Intermittent Operation

Acceptable Defects

Bright Spots

Black Spots

Fixed Pattern Noise (FPN)

Chicken Wire

Honeycomb

Scintillation

Signal to Noise Ratio (SNR)

Resolution

Figure of Merit (FOM)

Power Supply

Battery Compartment

Battery Usage Plan

Electrical Circuit Within the Intensifier Tube

Low Battery Indicator

Mounting System

Helmet Mounting

Mount Assembly

Locking Pin

Vertical Adjustment

Tilt Adjustment Lever

Fore and Aft Adjustment Knob

Eye Span Distance Adjustment Knob

Breakaway

Electrical Connection

Problems in NVG Adjustment

Tube Alignment

Collimation

Optical Image Differences

Focus Lane

Summary

Hoffmann 20/20 Focus Box

Controls and Indicators

Checking NVG System Resolution and Dynamic Range

The Resolution Pattern

Greyscale Outer Ring

Hoffmann 20/20 Focusing Procedure

The Generation Game

Omnibus

Generations

Full Face Goggles

Displaced Goggles

Generation 0

Generation I

Generation II

Super Generation II

Generation III

Generation III Plus and Generation III Omnibus X

Generation IV

XR5

Comparing US and European Classifications

More Terms

Figure of Merit (FOM)

Performance-based Not Technology-based

Summary

Aeromedical Factors When Using NVGS

Eyes When Using NVGs

Field of View (FOV)

Field of Regard (FOR)

Scanning Techniques

Scanning Patterns

Unaided Scan

Ambient or Artificial Light

NVG Eye Factors

Eye Stress and Fatigue

Night Adaptation

Eyes That Need Corrective Lenses

Visual Illusions

False Horizons

Flicker Vertigo

Fascination (Fixation)

Confusion of Ground Lights

Relative Motion Illusion

Lack of Motion Illusion

Wave Drift Illusion

Waterfall Illusion

Autokinesis

Structural Illusion

Height Perception Illusion

Size Distance Illusion

Altered Planes of Reference

Reversible Perspective Illusion

Crater Illusion

Light

Infrared Light

Monochromatic Adaptation

Ears When using NVGs

Proprioceptive System When Using NVGs

Postural Right Reflex

Vestibular Ocular Reflex

Fatigue When Using NVGs

NVG Fitting

Fitting Your Helmet

Balance Your Helmet

Building Your Fitness

Side Effects

Terrain and Environmental Factors

Illumination

Lumination

Natural Sources

Moon

Night Sky Illumination

Solar Influence

Artificial Sources of Light

Terrain

Terrain Reflectivity (Albedo)

Terrain Contrast

Terrain Shadowing

Weather and Atmospheric Obscurants

Atmospheric Absorption

Absorption

Scattering

Refraction

Reflection

Weather

Airborne Obscurants

Atmospheric Influence

Clouds

Thunderstorms and Lightning

Rain

Snow

Haze, Mist, Fog

Salt, Dust, Smoke, Ash, Pollen, Leaves, Grass and Bugs

Wind

Aircraft Configuration

Windshield

Shape

Wavelengths

Distance from User

Condition

Lighting

Cockpit Lighting

External Lighting

Cockpit Design

Risk Management for NVG Operations

Quick Review of Risk Management

Risk Management Plans

Risk Management Plan (RMP) Process

Risk Management Plan (RMP) Content

RMP Headings

Risk Matrix

Consequence Rating

Likelihood Rating

RMP Example

Threat Error Management (TEM) for NVG Operations

Threat

External Threats

Internal Threats

Organisational Threats

Error

Management

Pre-flight Brief

Crew Resource Management and Phraseology

Standard Phraseology

Crew Resource Management (CRM)

Eyes Inside/Outside Drill

NVG Scanning Procedures

Scanning

NVG Scanning Arcs Of Responsibility

Standard Words and Phrases

Standard Crew Interactions

NVG Standard Phraseology

Hover And Taxi Management Phraseology

In-Flight Phraseology

Identifying and Avoiding Obstacles Phraseology

Take-Off And Landing Phase Below 500 ft AGL Phraseology

Checks

Pre-lift-off and Pre-landing checks

Hover Checks

Instrument Performance Checks

Power Wind Plan (PWP) Statement

Use of Lights For NVG

External Lights in General

Position Lights

Anti-Collision Light

Strobe Lights

Landing Light / Searchlight / Night Scanner

Torch

Lip Light / Finger Light

Goggle Up/De-Goggle Procedure

On the Ground

Goggle Up Procedure : On the Ground

De-Goggle Procedure  : On the Ground

Goggle Up Procedure : In The Air

De-Goggle Procedure : In The Air

NVG Departure Profile

Restricted Instrument Flight Take-off (RIFTO)

Constant Angle and Standard Airfield Departure

Encountering Low Contrast Situations

NVG Approach Profiles

Standard NVG Approach Profile

HLS NVG Pinnacle Approaches

Departing an HLS

Arriving at an HLS

NVG Navigation

NVG Low-level Flight

Transition Between Flight Categories

Transition from NVG Flight to IFR Flight

Transition from IFR Flight to NVG Flight

Transition from NVG Flight to NVFR Flight

Transition from NVFR Flight to NVG Flight

NVG Emergencies

Helicopter Emergencies With NVGs In General

NVG Specific Emergencies

Radio Altimeter (RADALT) Failure

Goggle Failure Drill

Flying Pilot Goggle Failure

Non-flying Pilot Goggle Failure

Single Tube Failure

Inadvertent IMC (IIMC) Procedure

Entering IMC (IIMC)

AHTA Drill

During IIMC

Loss of Visual Reference (Brownout/Whiteout)

Landing Techniques

Take-off Techniques

Planning an NVG Flight

NVG Checklist

1.  NVGs

2.  AIRCRAFT

3.  CREW

4.  MISSION

5.  ROUTE

6.  WEATHER

7.  FLIGHT PLANNING

8.  POST FLIGHT

Explaining the NVG Checklist

1.  NVGs: Checklist Explained

Serviceable And Released

Mounted To Helmet And Focused

Battery Life

Backup If Required

2.  Aircraft: Checklist Explained

Serviceable And Released

NVFR or IFR Approved

Pre-flight Inspection

Ancillary Equipment

Weight And Balance

3.  Crew: Checklist Explained

Rested And Within Flight And Duty Times

Stop Time Calculated

Currency And Recency

4.  Mission: Checklist Explained

Purpose

Flight Timings

Airspace

Aerial Work Activity

5.  Route : Checklist Explained

Route And Working Area Selected and Assessed

Terrain Appreciation

LSALT Calculated

Wires And Obstacles Noted

Best Way To Look For Wires

Negotiating Wires and Obstacles

Wire Maps

6.  Weather : Checklist Explained

Australia: For NVG Operations, The Following Weather Requirements Will Apply And Are The Legal Minimums Within Australia

Five Key Elements Of The Weather

1.  Cloud Amount and Base

2.  Visibility

3.  Freezing Level

4.  Alternates and Holding Fuel

5.  Ambient Light

7.  Flight Planning: Checklist Explained

Flight Log

Mud Map

Flight Plan With Air Traffic Services (ATS).

Crew Briefing and Co-Ordination

Risks and Threats Discussed

IIMC Recovery Plan

NVG Sortie Crew Plan

8.  Post Flight: Checklist Explained

NVG Map Hints and Tips

Map Marking

Creating A Mud Map

Abbreviations and Acronyms

Glossary

Bibliography

About this Book

Night Vision Goggles for Helicopter Pilots is written by Captain Mike Becker, one of Australia's most experienced helicopter instructors. With over 16,000 helicopter flight hours and recipient of the Captain John Ashton Award for Flight Standards and Aviation Safety by the Guild of Air Pilots and Air Navigators of London, Mike's experience provides invaluable insights and real hands-on knowledge.

Mike Becker has been operating a helicopter flight school since 1995.  As Chief Pilot and Head of Training Operations, Mike has managed and operated a fleet of over 20 helicopters while employing a team of more than 30 instructors to deliver over 10,000 turbine training hours per year.  This book captures his experience as Chief Pilot and Chief Flight Instructor and the breadth of knowledge of the team of flight instructors who, over the years, have contributed to the continual improvement of this book.

This experience is evident in this practical, hands-on guide to NVG civilian operations.  It is written by a helicopter pilot for a helicopter pilot and demystifies the world of NVGs.

The information and teaching material in Night Vision Goggles for Helicopter Pilots covers the issues of sourcing and using NVGs, understanding how they work and operate, dealing with unique hazards and risks, flight planning for NVG operations, crew resource management considerations, helicopter emergencies, and establishing safe and regulatory-compliant operational systems. New terms like Omnibus, Gen III, ANVIS 9, microchannel plate, lumen, photocathode, infrared, chicken-wire, and more are clearly explained and simplified.

Although a technical theory book, it is written in plain English with easy-to-understand explanations supported by many photographs, illustrations and diagrams.

This book is a ground-breaking world-first comprehensive text.  It is a must for the new and current NVG helicopter aviator, bringing you out of the dark and into the light in terms of the depth of knowledge required for civilian NVG operations.

About the Author

Mike Becker is one of Australia’s most experienced helicopter instructors, with over 16,000 hours of rotary-wing flight experience. His career has taken him from the mountains in New Zealand to the outback of Australia to the jungles of Papua New Guinea. He has also worked in the United States, Italy and Borneo.

He has flown a range of helicopter types – the Robinson R22, Robinson R44, Bell 47, Hughes 269, Hughes 500, Bell 206, Bell 427, Bell 212, EC120, Dragon Fly, Brantley B2B, Enstrom EF28, Sikorsky S62A, Hiller

H12ET, Aerospatial AS350, Agusta 109E Power, Agusta 109S Grand, and the Agusta 119 Koala.

He is experienced in a comprehensive range of helicopter operations, including high altitude, remote area operations, mustering, firefighting, tourism, sling load operations, specialised long-line operations, search and rescue, and Night Vision Goggles operations.

Mike is a Grade One Flight Instructor and Flight Examiner who holds an Australian Air Transport Pilots Licence (Helicopter) and an Australian Commercial Pilots Licence (Fixed Wing).

Mike is the Chief Pilot and Head of Training for his own business Becker Helicopters, in Australia. He, and his wife Jan, established Becker Helicopters in 1997 with one Bell 47 and have grown the company through a love of helicopters, hard work, and determination.

Mike is the recipient of many awards, including the Captain John Ashton Award for Flight Standards and Aviation Safety by the Guild of Air Pilots and Air Navigators of London, which was awarded in recognition of over 18,000 accident-free flight training hours at Becker Helicopters. Mike has also authored Mike Becker’s Helicopter Handbook, first published in 1986, and a range of theory books and instructional videos. 

The History of Light

Since the beginning of time, darkness has been a source of protection, whereby those who could not see in the dark could hide away in a secure place to rest and be protected, additionally, those who could see in the dark could use its protection for hunting for food or attacking an enemy.  In most cases, with darkness being a source of protection, animals that were a danger to man were naturally afraid of light.  Therefore light, during times of darkness, evolved as a tool for man’s protection.

Therefore, the first Night Vision Device (NVD) can find its history in fire as the simple torch.  This torch may have consisted of a burning stick, possibly with fat or skin wound around one end, which shed light so that it allowed the holder to see in the dark.

As history progressed, better ways of seeing in the dark were invented.  This included using lanterns powered by oil, gas, and electricity to generate light, enabling man to utilise the dark for continued productivity and protection.

Man’s greatest predator has always been another man.  So, during times of war, the ability to see at night would be an advantage.  The question was how to make a device that allows you to see in the dark without being seen yourself?

As humankind began to accelerate into the technological age during World War I and II, we discovered and utilised artificial ways to generate light.  Initially, this was related to the light bulb and electricity use.  Probably the most famous was the searchlight.  As aviation began its steady improvement, aircraft flew night missions under the protection of darkness and height to bomb cities in enemy countries.  Large searchlights would penetrate the dark to search the sky, trying to light up a plane and give their gunners something to at which to aim.  The searchlight is a night vision device because it allows you to see into the darkness.

These NVDs are known as active night vision systems because they emit light to see.  However, active night vision systems have a significant problem; they emit light, allowing the enemy to identify your position.  This is not good if you don’t want to be seen or shot.  So, scientists began to experiment with various light types to develop a night vision system that would allow the user to see in the dark without being seen.  The creation of a device that would enable you to see in the dark without emitting any form of light is known as a passive night vision system.

Electricity

Scientists began to experiment with electricity to create a passive night vision device.  The original logic was that if electricity is a medium that is easily able to be modulated (increased or decreased) in strength, then if you turned whatever visible light that was available into electricity amplified the electricity before turning it back into visible light again, you might just be able to see in the dark by amplifying the visible image.

To prove the logic, all you had to do was look at past inventions where all sorts of electrical devices take in a small electrical current (flow of electricity) at one end and amplify it to produce a bigger flow at the other.

We know this works for sound, but what about light?

To work for light, something new had to be invented that replaced the sound amplifier.  This would become the job of the light intensifier tube.

The Intensifier Tube

Although this will be covered later in more detail, in its most straightforward description, the intensifier tube is a small vacuum-sealed device that collects light in one end and converts that light into electricity.  The electricity is then amplified before it is converted back into light that we can see as an intensified image on a viewing screen.

Summary

A Night Vision Device (NVD) is anything that will help the human eye "see" in the dark.  This may be using either an active or a passive NVD

To create a passive NVD, the light intensifier tube was invented, which takes whatever light available, amplifies it, then projects that intensified image onto a viewing screen so that the user can literally "see in the dark".

It is essential to understand that if there is no light, then there is nothing to be amplified, and, therefore, there is no image that can be seen on the viewing screen.

Science of Light

Light is something that we seem to take for granted, but we very rarely take the time to understand just what it is.  We often fail to realise that it is something physical, has various components, and can manipulate it, just like we do water or air.  To understand the more complex technical explanations of Night Vision Devices that will follow in this book, you need a basic understanding of what light is, how we describe it, and how it is divided.

The universe is made up of matter, the building blocks of matter being atoms, which are, in turn, made up of protons, electrons, and neutrons held together by an electrochemical bond.  This electro-chemical bond, consisting of positively charged protons, negatively charged electrons and neutral (no charge) neutrons, is essential in understanding how we use technology to enhance light.

Some of this matter is collected into objects.  These objects can be:

as large as suns, planets, asteroids, moons, etc.

as small as trees, animals, dust

artificial objects such as a desk, a car, a building, etc.

Some of this matter, particularly within a star, is burning.  However, the bulk of it is spread throughout the galaxy as hydrogen atoms, and since the universe is supposedly infinite in size, it logically means that there is an infinite supply of hydrogen atoms.

Hydrogen is the most prolific atom in the galaxy and is referred to as the building block of the universe.

A Star: The Source of Light

A star is a large celestial body of hot gases held together by gravity that radiates energy derived from thermonuclear hydrogen fusion.  In essence, it is a large atomic bomb exercising the full power of Einstein’s formula of E=MC².

(Energy = Mass x the speed of light squared (C2))

Our sun converts over 657 million tons of hydrogen into 653 tons of helium every second.  The missing 4 million tons of mass is discharged into space as energy.  It is calculated that the earth receives only about one two-billionths of this energy as the rest continues off into space.

As a star releases its power (energy), it pushes out photons.  A photon is several atoms grouped into packets that we detect and describe as light.  This explanation describes light as being made up of actual particles of matter (atoms) travelling outwards away from their source towards infinity.

Photons

There is much scientific debate regarding what makes up a photon.  It is probably most helpful to apply an analogy or example to help grasp a basic understanding. A photon is created when two or more atoms collide.

To give an example of a wave, simply drop a rock into a pond of water.  As the rock hits the water, its energy can be seen moving outwards in the form of a wave.

It is interesting to note here that the water itself is not necessarily moving away from the rock; instead, the energy wave is passed on from one particle of water to the next.  This is the basis of an energy wave.

The electromagnetic wave or electromagnetic radiation emitted from our sun is classified into several types according to the frequency of its wave; these types include (in order of