A helmet-mounted display (HMD) is a device used in aircraft to project information to the pilot's eyes. Its scope is similar to that of

head-up display A head-up display, or heads-up display, also known as a HUD (), is any transparent display that presents data without requiring users to look away from their usual viewpoints. The origin of the name stems from a pilot being able to view informa ...

s (HUD) on an aircrew's visor or reticle. An HMD provides the pilot with

situation awareness Situational awareness or situation awareness (SA) is the perception of environmental elements and events with respect to time or space, the comprehension of their meaning, and the projection of their future status. An alternative definition is tha ...

, an enhanced image of the scene, and in military applications cue weapons systems, to the direction their head is pointing. Applications which allow cuing of weapon systems are referred to as helmet-mounted sight and display (HMSD) or helmet-mounted sights (HMS).

Requirement

Aviation HMD designs serve these purposes: * using the head angle as a pointer to direct air-to-air and air-to-ground weapons seekers or other sensors (e.g.,

radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...

FLIR Forward-looking infrared (FLIR) cameras, typically used on military and civilian aircraft, use a thermographic camera that senses infrared radiation. The sensors installed in forward-looking infrared cameras, as well as those of other thermal ...

) to a target merely by pointing his head at the target and actuating a switch via

HOTAS HOTAS, an acronym of hands on throttle-and-stick, is the concept of placing buttons and switches on the throttle lever and flight control stick in an aircraft's cockpit. By adopting such an arrangement, pilots are capable of performing all vit ...

controls. In close combat prior to HMDs, the pilot had to align the aircraft to shoot at a target. HMDs allow the pilot to simply point his head at a target, designate it to weapon and shoot. * displaying targeting and aircraft performance information (such as

airspeed In aviation, airspeed is the speed of an aircraft relative to the air. Among the common conventions for qualifying airspeed are: * Indicated airspeed ("IAS"), what is read on an airspeed gauge connected to a Pitot-static system; * Calibrated ...

altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context ...

, target range, weapon seeker status, "g", etc.) to the pilot while "heads-up", eliminating the need to look inside the flightdeck. * displaying sensor video for the purpose of: ** verification that the chosen sensor has been cued to the right target or location without requiring the pilot to look inside the flightdeck ** viewing outside terrain using sensor video in degraded visual conditions. HMD systems, combined with High Off- Boresight (HOBS) weapons, results in the ability for aircrew to attack and destroy nearly any target seen by the pilot. These systems allow targets to be designated with minimal aircraft maneuvering, minimizing the time spent in the threat environment, and allowing greater lethality, survivability, and pilot

situational awareness Situational awareness or situation awareness (SA) is the perception of environmental elements and events with respect to time or space, the comprehension of their meaning, and the projection of their future status. An alternative definition is tha ...

History

In 1962,

Hughes Aircraft Company The Hughes Aircraft Company was a major American aerospace and defense contractor founded on February 14, 1934 by Howard Hughes in Glendale, California, as a division of Hughes Tool Company. The company was known for producing, among other ...

revealed the Electrocular, a compact CRT, head-mounted monocular display that reflected a TV signal onto a transparent eyepiece. From 1966 throughout the early 1970s , Mirage 3CZ and Mirage F1AZ of the SAAF (

South African Air Force "Through hardships to the stars" , colours = , colours_label = , march = , mascot = , anniversaries = , equipment ...

) was the first to use a locally developed helmet mounted sight. South Africa was the first country to develop and use HMSs in combat, a locally developed helmet-mounted sight integrated with the Armscor V3A heat seeking missile. This enables the pilot to make off-bore attacks, without having to maneuver to the optimum firing position. After the South African system had been proven in combat, playing a role in downing Soviet aircraft over Angola, the Soviets embarked on a crash program to counter the technology. As a result, the

MiG-29 The Mikoyan MiG-29 (russian: Микоян МиГ-29; NATO reporting name: Fulcrum) is a twin-engine fighter aircraft designed in the Soviet Union. Developed by the Mikoyan design bureau as an air superiority fighter during the 1970s, the Mi ...

was fielded in 1985 with an HMD and a high off-boresight weapon ( R-73), giving them an advantage in close maneuvering engagements. Several nations responded with programs to counter the MiG-29/HMD/R-73 (and later

Su-27 The Sukhoi Su-27 (russian: Сухой Су-27; NATO reporting name: Flanker) is a Soviet-origin twin-engine supermaneuverable fighter aircraft designed by Sukhoi. It was intended as a direct competitor for the large US fourth-generation j ...

) combination once its effectiveness was known, principally through access to former East German MiG-29s that were operated by the unified German Air Force. One of the first aircraft with simple HMD devices appeared for experimental purpose in the mid-1970s to aid in targeting heat seeking missiles. These rudimentary devices were better described as Helmet-Mounted Sights. The

US Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

's Visual Target Acquisition System (VTAS), made by

Honeywell Honeywell International Inc. is an American publicly traded, multinational conglomerate corporation headquartered in Charlotte, North Carolina. It primarily operates in four areas of business: aerospace, building technologies, performance ma ...

Corporation was a simple mechanical "ring and bead"–style sight fitted to the front of the pilot's helmet that was flown in the 1974–78

ACEVAL/AIMVAL The Air Combat Evaluation (ACEVAL) and the Air Intercept Missile Evaluation (AIMVAL) were two back-to-back Joint Test & Evaluations chartered by the United States Department of Defense that ran from 1974-78 at Nellis Air Force Base in Nevada. Both ...

on U.S. F-14 and

F-15 The McDonnell Douglas F-15 Eagle is an American twin-engine, all-weather tactical fighter aircraft designed by McDonnell Douglas (now part of Boeing). Following reviews of proposals, the United States Air Force selected McDonnell Douglas's ...

fighters. VTAS received praise for its effectiveness in targeting off-boresight missiles, but the U.S. did not pursue fielding it except for integration into late-model Navy F-4 Phantoms equipped with the

AIM-9 Sidewinder The AIM-9 Sidewinder (where "AIM" stands for "Air Intercept Missile") is a short-range air-to-air missile which entered service with the US Navy in 1956 and subsequently was adopted by the US Air Force in 1964. Since then the Sidewinder has prove ...

from 1969. HMDs were also introduced in

helicopters A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attribu ...

during this time - examples include the

Boeing AH-64 Apache The Boeing AH-64 Apache () is an American twin- turboshaft attack helicopter with a tailwheel-type landing gear arrangement and a tandem cockpit for a crew of two. It features a nose-mounted sensor suite for target acquisition and night v ...

with the Integrated Helmet and Display Sighting System (IHADSS) demonstrated in 1985. One successful HMD was the

Israeli Air Force The Israeli Air Force (IAF; he, זְרוֹעַ הָאֲוִיר וְהֶחָלָל, Zroa HaAvir VeHahalal, tl, "Air and Space Arm", commonly known as , ''Kheil HaAvir'', "Air Corps") operates as the aerial warfare branch of the Israel Defens ...

Elbit DASH series, fielded in conjunction with the Python 4, in the early 1990s. The U.S., UK, and Germany pursued a HMD combined with

ASRAAM The Advanced Short Range Air-to-Air Missile (ASRAAM), also known by its United States designation AIM-132, is an imaging infrared homing (heat seeking) air-to-air missile, produced by MBDA UK, that is designed for close-range combat. It is in ...

systems. Technical difficulties led to the U.S. abandoning ASRAAM, instead funding development of the AIM-9X and the Joint Helmet-Mounted Cueing System in 1990. American and European fighter HMDs became widely used in the late 1990s and early 2000s. The first civilian use of HMD on aircraft was the Elbit SkyLens HMD on ATR 72/42 airplane.

Technology

While conceptually simple, implementation of aircraft HMDs is quite complex. There are many variables: * precision – the angular error between the line-of-sight and the derived cue. The position of the ''helmet'' is what is used to point the missile; it thus must be calibrated and fit securely on the pilot's head. The line between the pilot's eye and the

reticle A reticle, or reticule also known as a graticule, is a pattern of fine lines or markings built into the eyepiece of an optical device such as a telescopic sight, spotting scope, theodolite, optical microscope or the screen of an oscilloscop ...

on the visor is known as the

line of sight The line of sight, also known as visual axis or sightline (also sight line), is an imaginary line between a viewer/observer/ spectator's eye(s) and a subject of interest, or their relative direction. The subject may be any definable object taken ...

(LOS) between the aircraft and the intended target. The user's eye must stay aligned with the sight; in other words, current HMDs cannot sense where the eye is looking, but can place a "

pipper The predicted impact point (PIP) is the location that a ballistic projectile (e.g. bomb, missile, bullet) is expected to strike if fired. The PIP is almost always actively determined by a targeting computer, which then projects a PIP marker (a "pi ...

" between the eye and the target. * latency or slew rate – how much lag there is between the helmet and the cue. * field of regard – the angular range over which the sight can still produce a suitably accurate measurement. * weight and balance – total helmet weight and its

center of gravity In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force ma ...

, which are particularly important under high "''g''" maneuvers. Weight is the largest problem faced by fighter aircraft HMD designers. This is much less a concern for helicopter applications, making elaborate helicopter HMDs common. * safety and flightdeck compatibility, including

ejection seat In aircraft, an ejection seat or ejector seat is a system designed to rescue the pilot or other crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rock ...

compatibility. * optical characteristics – calibration, sharpness, distant focus (or '

Collimation A collimated beam of light or other electromagnetic radiation has parallel rays, and therefore will spread minimally as it propagates. A perfectly collimated light beam, with no divergence, would not disperse with distance. However, diffraction ...

', a technique used to present the images at a distant focus, which improves the readability of images),

monocular A monocular is a compact refracting telescope used to magnify images of distant objects, typically using an optical prism to ensure an erect image, instead of using relay lenses like most telescopic sights. The volume and weight of a mono ...

vs. binocular imagery, eye dominance, and binocular rivalry. * durability and ability to handle day-to-day wear and tear. * cost, including integration and training. * fit and interfacing the aviator's head to the aircraft – head

anthropometry Anthropometry () refers to the measurement of the human individual. An early tool of physical anthropology, it has been used for identification, for the purposes of understanding human physical variation, in paleoanthropology and in various atte ...

and facial

anatomy Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having i ...

make helmet-fitting a crucial factor in the aviator's ability to interface with the aircraft systems. Misalignment or helmet shift can cause an inaccurate picture.

Head tracking

HMD designs must sense the orientation (elevation, azimuth and roll) and in some cases the position (x, y, and z) of the pilot's head relative to the airframe with sufficient precision even under high "''g''", vibration, and during rapid head movement. Five basic methods are used in current HMD technology – inertial, optical, electromagnetic, sonic, and hybrid. Hybrid trackers use a combination of sensors such as inertial and optical to improve tracking accuracy, update rate, and latency.

Hybrid inertial optical

Hybrid inertial tracking systems employ a sensitive

Inertial Measurement Unit An inertial measurement unit (IMU) is an electronic device that measures and reports a body's specific force, angular rate, and sometimes the orientation of the body, using a combination of accelerometers, gyroscopes, and sometimes magnetomet ...

(IMU) and an optical sensor to provide reference to the aircraft. MEMS based IMUs benefit from high update rates such as 1,000 Hz but suffer from precession and drift over time, so they cannot be used alone. In this class of tracker, the optical sensor is used to constrain IMU drift. As a result, hybrid inertial/optical trackers feature low latency and high accuracy. The

Thales Thales of Miletus ( ; grc-gre, Θαλῆς; ) was a Greek mathematician, astronomer, statesman, and pre-Socratic philosopher from Miletus in Ionia, Asia Minor. He was one of the Seven Sages of Greece. Many, most notably Aristotle, regarded ...

Scorpion® HMCS and HMIT HMDs utilize a tracker made by InterSense called the Hybrid Optical-based Inertial Tracker (HObIT).

Optical

Optical Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultravio ...

systems employ

infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of Light, visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from ...

emitters on the helmet (or flightdeck) infrared detectors in the flightdeck (or helmet), to measure the pilot's head position. The main limitations are restricted fields of regard and sensitivity to sunlight or other heat sources. The MiG-29/AA-11 Archer system uses this technology. The Cobra HMD as used on both the Eurofighter Typhoon and the JAS39 Gripen both employ the optical helmet tracker developed by Denel Optronics (now part of Zeiss Optronics).

Electromagnetic

Electromagnetic In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions o ...

sensing designs use coils (in the helmet) placed in an alternating field (generated in the flightdeck) to produce alternating electrical

voltage Voltage, also known as electric pressure, electric tension, or (electric) potential difference, is the difference in electric potential between two points. In a static electric field, it corresponds to the work needed per unit of charge to ...

s based on the movement of the helmet in multiple axes. This technique requires precise magnetic mapping of the flightdeck to account for

ferrous In chemistry, the adjective Ferrous indicates a compound that contains iron(II), meaning iron in its +2 oxidation state, possibly as the divalent cation Fe2+. It is opposed to " ferric" or iron(III), meaning iron in its +3 oxidation state, suc ...

and

conductive In physics and electrical engineering, a conductor is an object or type of material that allows the flow of charge (electric current) in one or more directions. Materials made of metal are common electrical conductors. Electric current is gene ...

materials in the seat, flightdeck sills and canopy to reduce angular errors in the measurement.

Sonic

Acoustic sensing designs use ultrasonic sensors to monitor the pilot's head position while being updated by computer software in multiple axes. Typical operating frequencies are in the 50 to 100 kHz range and can be made to carry audio sound information directly to the pilot's ears via subcarrier modulation of the sensong ultrasonic sensing signals.

Optics

Older HMDs typically employ a compact CRT embedded in the helmet, and suitable

optics Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultrav ...

to display

symbology A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different co ...

on to the pilot's visor or reticle, focused at

infinity Infinity is that which is boundless, endless, or larger than any natural number. It is often denoted by the infinity symbol . Since the time of the ancient Greeks, the philosophical nature of infinity was the subject of many discussions am ...

. Modern HMDs have dispensed with the CRT in favor of micro-displays such as liquid crystal on silicon (LCOS) or liquid crystal display (LCD) along with an LED illuminator to generate the displayed image. Advanced HMDs can also project FLIR or NVG imagery. A recent improvement is the capability to display color symbols and video.

Major systems

Systems are presented in rough chronological order of

initial operating capability Initial operating capability or initial operational capability (IOC) is the state achieved when a capability is available in its minimum usefully deployable form. The term is often used in government or military procurement. The United States D ...

Integrated Helmet And Display Sight System (IHADSS)

Integrated Helmet and Display Sighting System

In 1985, the

U.S. Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cl ...

fielded the

AH-64 Apache The Boeing AH-64 Apache () is an American twin- turboshaft attack helicopter with a tailwheel-type landing gear arrangement and a tandem cockpit for a crew of two. It features a nose-mounted sensor suite for target acquisition and night v ...

and with it the Integrated Helmet and Display Sighting System (IHADSS), a new helmet concept in which the role of the helmet was expanded to provide a visually coupled interface between the aviator and the aircraft. The

M142 IHADSS is fitted with a 40°-by-30° field of view, video-with-symbology monocular display. IR emitters allow a slewable

thermographic camera Infrared thermography (IRT), thermal video and/or thermal imaging, is a process where a thermal camera captures and creates an image of an object by using infrared radiation emitted from the object in a process, which are examples of infrared ...

sensor, mounted on the nose of the aircraft, to be slaved to the aviator's head movements. The display also enables

Nap-of-the-earth Nap-of-the-earth (NOE) is a type of very low-altitude flight course used by military aircraft to avoid enemy detection and attack in a high-threat environment. Other, mostly older terms include "ground-hugging", "terrain masking", "flying under t ...

night navigation. IHADSS is also used on the Italian

Agusta A129 Mangusta The Agusta A129 Mangusta ( en, Mongoose) is an attack helicopter originally designed and produced by Italian company Agusta. It is the first attack helicopter to be designed and produced wholly in Europe. It has continued to be developed by Agus ...

. :

ZSh-5 / Shchel-3UM

The Russian designed Shchel-3UM HMD design is fit to the ZSh-5 series helmet (and later ZSh-7 helmets), and is used on the

and

in conjunction with the

R-73 (missile) The R-73 (NATO reporting name AA-11 ''Archer'') is a short-range air-to-air missile developed by Vympel NPO that entered service in 1984. Development The R-73 was developed to replace the earlier R-60 (AA-8 'Aphid') weapon for short-range use b ...

. The HMD/Archer combination gave the MiG-29 and Su-27 a significantly improved close combat capability and quickly became the most widely deployed HMD in the world.

Display and sight helmet (DASH)

The

Elbit Systems Elbit Systems Ltd. is an Israel-based international defense electronics company engaged in a wide range of programs throughout the world. The company, which includes Elbit Systems and its subsidiaries, operates in the areas of aerospace, land ...

DASH III was the first modern Western HMD to achieve operational service. Development of the DASH began during the mid-1980s, when the IAF issued a requirement for F-15 and F-16 aircraft. The first design entered production around 1986, and the current GEN III helmet entered production during the early to mid-1990s. The current production variant is deployed on IDF F-15, and

F-16 The General Dynamics F-16 Fighting Falcon is a single-engine multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successf ...

aircraft. Additionally, it has been certified on the

F/A-18 The McDonnell Douglas F/A-18 Hornet is an all-weather, twin-engine, supersonic, carrier-capable, multirole combat aircraft, designed as both a fighter and attack aircraft (hence the F/A designation). Designed by McDonnell Douglas (now part ...

and F-5. The DASH III has been exported and integrated into various legacy aircraft, including the

MiG-21 The Mikoyan-Gurevich MiG-21 (russian: Микоян и Гуревич МиГ-21; NATO reporting name: Fishbed) is a supersonic jet fighter and interceptor aircraft, designed by the Mikoyan-Gurevich Design Bureau in the Soviet Union. Its nickn ...

. It also forms the baseline technology for the US JHMCS. The DASH GEN III is a wholly embedded design, where the complete optical and position sensing coil package is built within the helmet (either USAF standard HGU-55/P or the Israeli standard HGU-22/P) using a spherical visor to provide a collimated image to the pilot. A quick-disconnect wire powers the display and carries video drive signals to the helmet's

Cathode Ray Tube A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms ( oscilloscope), ...

(CRT). DASH is closely integrated with the aircraft's weapon system, via a

MIL-STD-1553 MIL-STD-1553 is a military standard published by the United States Department of Defense that defines the mechanical, electrical, and functional characteristics of a serial data bus. It was originally designed as an avionic data bus for use with ...

B bus. Latest model DASH IV is currently integrated on India's

HAL Tejas The HAL Tejas is an Indian, single engine, delta wing, light multirole fighter designed by the Aeronautical Development Agency (ADA) in collaboration with Aircraft Research and Design Centre (ARDC) of Hindustan Aeronautics Limited (HAL) for ...

Joint Helmet-Mounted Cueing System (JHMCS)

After the U.S. withdrawal from

, the U.S. pursued and fielded JHMCS in conjunction with the

Raytheon Raytheon Technologies Corporation is an American multinational aerospace and defense conglomerate headquartered in Arlington, Virginia. It is one of the largest aerospace and defense manufacturers in the world by revenue and market capitali ...

AIM-9X, in November 2003 with the 12th and 19th Fighter Squadrons at

Elmendorf AFB Elmendorf Air Force Base is a United States Air Force (USAF) facility in Anchorage, Alaska. Originally known as Elmendorf Field, it became Elmendorf Air Force Base after World War II. It is the home of the Headquarters, Alaskan Air Command (AL ...

, Alaska. The Navy conducted RDT&E on the

C as lead platform for JHMCS, but fielded it first on the F/A-18 Super Hornet E and F aircraft in 2003. The USAF is also integrating JHMCS into its F-15E, F-15C, and F-16C aircraft. JHMCS is a derivative of the DASH III and the Kaiser Agile Eye HMDs, and was developed by Vision Systems International (VSI), a joint venture company formed by

Rockwell Collins Rockwell Collins was a multinational corporation headquartered in Cedar Rapids, Iowa, providing avionics and information technology systems and services to government agencies and aircraft manufacturers. It was formed when the Collins Radio Co ...

and

Elbit Elbit Systems Ltd. is an Israel-based international defense electronics company engaged in a wide range of programs throughout the world. The company, which includes Elbit Systems and its subsidiaries, operates in the areas of aerospace, land ...

(Kaiser Electronics is now owned by Rockwell Collins).

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and ...

integrated the system into the

and began low-rate initial production delivery in fiscal year 2002. JHMCS is employed in the

A++/C/D/E/F, F-15C/D/E, and

Block 40/50 with a design that is 95% common to all platforms. Unlike the DASH, which is integrated into the helmet itself, JHMCS assemblies attach to modified HGU-55/P, HGU-56/P or HGU-68/P helmets. JHMCS employs a newer, faster digital processing package, but retains the same type of electromagnetic position sensing as the DASH. The CRT package is more capable, but remains limited to monochrome presentation of cursive symbology. JHMCS provides support for raster scanned imagery to display FLIR/ IRST pictures for night operations and provides collimated symbology and imagery to the pilot. The integration of the night-vision goggles with the JHMCS was a key requirement of the program. When combined with the AIM-9X, an advanced short-range dogfight weapon that employs a Focal Plane Array seeker and a thrust vectoring tail control package, JHMCS allows effective target designation up to 80 degrees either side of the aircraft's nose. In March 2009, a successful 'Lock on After Launch' firing of an ASRAAM at a target located behind the wing-line of the ‘shooter' aircraft, was demonstrated by a Royal Australian Air Force (RAAF) F/A-18 using JHMCS.

TARGO II

designed system is used by Qatar and India on

Rafale The Dassault Rafale (, literally meaning "gust of wind", and "burst of fire" in a more military sense) is a French twin-engine, canard delta wing, multirole fighter aircraft designed and built by Dassault Aviation. Equipped with a wide rang ...

F3R

Helmet Mounted Integrated Targeting (HMIT)

introduced the Scorpion® Head/Helmet-Mounted Display System to the military aviation market in 2008. In 2010, Scorpion was the winner of the USAF/ANG/AFRes Helmet Mounted Integrated Targeting (HMIT) program. The HMIT system was qualified and deployed on both A-10 and F-16 platforms in 2012. Starting in 2018, the installed base of HMIT systems went through a helmet tracker upgrade. The original AC magnetic tracking sensor was replaced by an inertial-optical hybrid tracker called Hybrid Optical based Inertial Tracker (HObIT). The HObIT was developed by InterSense and tested by Thales in 2014. Scorpion has the distinction of being the first HMD introduced and deployed that can display full-color conformal symbology. It is used along with the aircraft mission system to cue the aircraft targeting pods, gimbaled sensors, and high off-boresight missiles. Scorpion provides an "eyes out" capability: even when objects may be obscured from view, Scorpion can provide visual graphic cues to the near-field display. Unlike most HMDs which require custom helmets, Scorpion was designed to be installed on a standard issue HGU-55/P and HGU-68/P helmets and is fully compatible with standard issue U.S. Pilot Flight Equipment without special fitting. It is also fully compatible with standard unmodified AN/AVS-9

Night Vision Goggles A night-vision device (NVD), also known as a night optical/observation device (NOD), night-vision goggle (NVG), is an optoelectronic device that allows visualization of images in low levels of light, improving the user's night vision. The dev ...

(NVG) and Panoramic Night Vision Goggles (PNVG). Pilots, using Scorpion, can view both the night vision image and the symbols on the display. Scorpion uses a novel optical system featuring a light-guide optical element (LOE) which provides a compact color collimated image to the pilot. The display can be positioned by each pilot, thereby eliminating the need for precise helmet position on the user's head or special helmet fitting. Software correction accommodates the display position, providing an accurate image to the pilot and allowing the Scorpion HMCS to be installed onto a pilot's existing helmet. A visor can be deployed in front of the display providing protection during ejection. The visor can be clear, glare, high contrast, gradient, or laser protective. For night operations, an NVG mount can be installed in place of the visor during flight. Once installed, NVGs can be placed in front of the display, thus allowing the pilot to view both the display symbols as well as the NVG image simultaneously. Scorpion is also used by Tactical Air Support Inc. on F-5AT, by French Air Force for

F4, by the Spanish Airforce on EF-18s, the AC-130W Stinger II Gunship, and the

Lockheed Martin F-22 Raptor The Lockheed Martin F-22 Raptor is an American single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). As the result of the USAF's Advanced Tactical Fighter (ATF) program, th ...

Aselsan AVCI

Aselsan of Turkey is working to develop a similar system to the French TopOwl Helmet, called the AVCI Helmet Integrated Cueing System. The system will also be utilized into the

T-129 The TAI/AgustaWestland T129 ATAK is a twin-engine, tandem seat, multi-role, all-weather attack helicopter based on the Agusta A129 Mangusta platform. The T129 was developed by Turkish Aerospace Industries (TAI) in partnership with Leonardo (Ag ...

Turkish Attack Helicopter.

TopOwl-F(Topsight/TopNight)

The French thrust vectoring

Matra Matra (an acronym for Mécanique Aviation Traction) was a French industrial conglomerate. During its years of operation, it was engaged in a wide range of business activities, primarily focused around automobiles, bicycles, aeronautics and wea ...

MICA (missile) The Missile d’Interception, de Combat et d’Auto-défense (English: "Interception, Combat and Self-protection Missile") or MICA is a French anti-air multi-target, all weather, fire-and-forget short and medium-range missile system manufactured ...

for its

Dassault Rafale The Dassault Rafale (, literally meaning "gust of wind", and "burst of fire" in a more military sense) is a French twin-engine, canard delta wing, multirole fighter aircraft designed and built by Dassault Aviation. Equipped with a wide range ...

and late-model

Mirage 2000 The Dassault Mirage 2000 is a French multirole, single-engine, fourth-generation jet fighter manufactured by Dassault Aviation. It was designed in the late 1970s as a lightweight fighter to replace the Mirage III for the French Air Force (' ...

fighters was accompanied by the Topsight HMD by Sextant Avionique. TopSight provides a 20 degree FoV for the pilot's right eye, and cursive symbology generated from target and aircraft parameters. Electromagnetic position sensing is employed. The Topsight helmet uses an integral embedded design, and its contoured shape is designed to provide the pilot with a wholly unobstructed field of view. TopNight, a Topsight derivative, is designed specifically for adverse weather and night air to ground operations, employing more complex optics to project infrared imagery overlaid with symbology. The most recent version the Topsight has been designated TopOwl-F, and is qualified on the Mirage-2000-5 Mk2 and Mig-29K.

Eurofighter Helmet-Mounted Symbology System

Royal Air Force Typhoon Pilot's Helmet MOD 45158393

The

Eurofighter Typhoon The Eurofighter Typhoon is a European multinational twin-engine, canard delta wing, multirole fighter. The Typhoon was designed originally as an air-superiority fighter and is manufactured by a consortium of Airbus, BAE Systems and Leonardo ...

utilizes the Helmet-Mounted Symbology System (HMSS) developed by

BAE Systems BAE Systems plc (BAE) is a British multinational arms, security, and aerospace company based in London, England. It is the largest defence contractor in Europe, and ranked the seventh-largest in the world based on applicable 2021 revenue ...

and

Pilkington Optronics Pilkington is a Japanese-owned glass-manufacturing company which is based in Lathom, Lancashire, United Kingdom. In the UK it includes several legal entities and is a subsidiary of Japanese company NSG Group. Prior to its acquisition by NSG ...

. Named the Striker and later version Striker II. It is capable of displaying both raster imagery and cursive symbology, with provisions for embedded NVGs. As with the DASH helmet, the system employs integrated position sensing to ensure that symbols representing outside-world entities move in line with the pilot's head movements.

Helmet-Mounted Display System

Vision Systems International (VSI; the

joint venture) along with Helmet Integrated Systems, Ltd. developed the Helmet-Mounted Display System (HMDS) for the

F-35 The Lockheed Martin F-35 Lightning II is an American family of single-seat, single-engine, all-weather stealth multirole combat aircraft that is intended to perform both air superiority and strike missions. It is also able to provide elect ...

Joint Strike Fighter aircraft. In addition to standard HMD capabilities offered by other systems, HMDS fully utilizes the advanced avionics architecture of the F-35 and provides the pilot video with imagery in day or night conditions. Consequently, the F-35 is the first tactical fighter jet in 50 years to fly without a HUD. A BAE Systems helmet was considered when HMDS development was experiencing significant problems, but these issues were eventually worked out. The Helmet-Mounted Display System was fully operational and ready for delivery in July 2014.

Jedeye

Jedeye is a new system recently introduced by Elbit Systems especially to meet Apache and other rotary wing platform requirements. The system is designed for day, night and brownout flight environments. Jedeye has a 70 x 40 degree FOV and 2250x1200 pixels resolution.

Cobra

Sweden's

JAS 39 Gripen The Saab JAS 39 Gripen (; English: ''griffin'') is a light single-engine multirole fighter aircraft manufactured by the Swedish aerospace and defense company Saab AB. The Gripen has a delta wing and canard configuration with relaxed stabilit ...

fighter utilizes the Cobra HMD. The helmet is a further development and refinement of the Striker helmet developed for the Eurofighter by BAE Systems. The refinement is done by BAE in partnership with Denel Cumulus.

Future technology

* RCEVS is developing a standard view Night Vision Cueing & Display (NVCD) for the U.S. Navy. * Eye tracking – Eye trackers measure the point of gaze relative to the direction of the head, allowing a computer to sense where the user is looking. These systems are not currently used in aircraft. * Direct retinal projection – Systems that project information directly onto the wearer's

retina The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which the ...

with a low-powered

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The ...

(

virtual retinal display A virtual retinal display (VRD), also known as a retinal scan display (RSD) or retinal projector (RP), is a display technology that draws a raster display (like a television) directly onto the retina of the eye. History In the past similar s ...

) are also in experimentation.

References

Bibliography

External links

USAARL Helmet Mounted Displays- Sensation, Perception and Cognitive Issues

Thales Visionix

Vision Systems International

User survey of HMD requirements

{{Mixed reality Display technology Eyewear Military electronics Avionics Equipment of the United States Air Force Wearable computers