Republic F-105B with avionics layout 060831-F-1234S-046

Avionics (a blend of ''aviation'' and ''electronics'') are the electronic systems used on

aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engine ...

. Avionic systems include communications,

navigation Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...

, the display and management of multiple systems, and the hundreds of systems that are fitted to aircraft to perform individual functions. These can be as simple as a

searchlight A searchlight (or spotlight) is an apparatus that combines an extremely bright source (traditionally a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a particular direc ...

for a

police helicopter Police aviation is the use of aircraft in police operations. Police services commonly use aircraft for traffic control, ground support, search and rescue, high-speed car pursuits, observation, air patrol and control of large-scale public event ...

or as complicated as the tactical system for an

airborne early warning Airborne or Airborn may refer to: Arts, entertainment, and media Films * ''Airborne'' (1962 film), a 1962 American film directed by James Landis * ''Airborne'' (1993 film), a comedy–drama film * ''Airborne'' (1998 film), an action film sta ...

platform.

History

The term "avionics" was coined in 1949 by Philip J. Klass, senior editor at ''

Aviation Week & Space Technology ''Aviation Week & Space Technology'', often abbreviated ''Aviation Week'' or ''AW&ST'', is the flagship magazine of the Aviation Week Network. The weekly magazine is available in print and online, reporting on the aerospace, defense and aviati ...

'' magazine as a

portmanteau A portmanteau word, or portmanteau (, ) is a blend of words

Radio communication Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...

was first used in aircraft just prior to World War I. The first airborne radios were in

zeppelin A Zeppelin is a type of rigid airship named after the German inventor Count Ferdinand von Zeppelin () who pioneered rigid airship development at the beginning of the 20th century. Zeppelin's notions were first formulated in 1874Eckener 1938, p ...

s, but the military sparked development of light radio sets that could be carried by heavier-than-air craft, so that

aerial reconnaissance Aerial reconnaissance is reconnaissance for a military or strategic purpose that is conducted using reconnaissance aircraft. The role of reconnaissance can fulfil a variety of requirements including artillery spotting, the collection of imag ...

biplanes could report their observations immediately in case they were shot down. The first experimental radio transmission from an airplane was conducted by the US Navy in August 1910. The first aircraft radios transmitted by

radiotelegraphy Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for ...

, so they required two-seat aircraft with a second crewman to tap on a

telegraph key A telegraph key is a specialized electrical switch used by a trained operator to transmit text messages in Morse code in a telegraphy system. Keys are used in all forms of electrical telegraph systems, including landline (also called wire) t ...

to spell out messages by

Morse code Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code is named after Samuel Morse, one ...

. During World War I, AM voice two way radio sets were made possible in 1917 by the development of the triode

vacuum tube A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type kn ...

, which were simple enough that the pilot in a single seat aircraft could use it while flying.

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, ships, spacecraft, guided missiles, motor vehicles, ...

, the central technology used today in aircraft navigation and

air traffic control Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airs ...

, was developed by several nations, mainly in secret, as an

air defense Anti-aircraft warfare, counter-air or air defence forces is the battlespace response to aerial warfare, defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It includes surface based, ...

system in the 1930s during the runup to

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

. Many modern avionics have their origins in World War II wartime developments. For example,

autopilot An autopilot is a system used to control the path of an aircraft, marine craft or spacecraft without requiring constant manual control by a human operator. Autopilots do not replace human operators. Instead, the autopilot assists the operator' ...

systems that are commonplace today began as specialized systems to help bomber planes fly steadily enough to hit precision targets from high altitudes. Britain's 1940 decision to share its radar technology with its US ally, particularly the

magnetron The cavity magnetron is a high-power vacuum tube used in early radar systems and currently in microwave ovens and linear particle accelerators. It generates microwaves using the interaction of a stream of electrons with a magnetic field whil ...

, in the famous

Tizard Mission The Tizard Mission, officially the British Technical and Scientific Mission, was a British delegation that visited the United States during WWII to obtain the industrial resources to exploit the military potential of the research and development ( ...

, significantly shortened the war. Modern avionics is a substantial portion of military aircraft spending. Aircraft like the

F-15E The McDonnell Douglas (now Boeing) F-15E Strike Eagle is an American all-weather multirole strike fighter derived from the McDonnell Douglas F-15 Eagle. The F-15E was designed in the 1980s for long-range, high-speed interdiction without relyin ...

and the now retired

F-14 The Grumman F-14 Tomcat is an American carrier-capable supersonic aircraft, supersonic, twinjet, twin-engine, two-seat, twin-tail, variable-sweep wing fighter aircraft. The Tomcat was developed for the United States Navy's Naval Fighter Experi ...

have roughly 20 percent of their budget spent on avionics. Most modern

helicopter 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 attribute ...

s now have budget splits of 60/40 in favour of avionics. The civilian market has also seen a growth in cost of avionics. Flight control systems (

fly-by-wire Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires, and flight control ...

) and new navigation needs brought on by tighter airspaces, have pushed up development costs. The major change has been the recent boom in consumer flying. As more people begin to use planes as their primary method of transportation, more elaborate methods of controlling aircraft safely in these high restrictive airspaces have been invented.

Modern avionics

Avionics plays a heavy role in modernization initiatives like the

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...

's (FAA) Next Generation Air Transportation System project in the United States and the

Single European Sky ATM Research Single European Sky ATM Research (SESAR) is a collaborative project to completely overhaul European airspace and its air traffic management (ATM). The actual program is managed by the SESAR Joint Undertaking as a public–private partnership (PP ...

(SESAR) initiative in Europe. The Joint Planning and Development Office put forth a roadmap for avionics in six areas: * Published Routes and Procedures – Improved navigation and routing * Negotiated Trajectories – Adding data communications to create preferred routes dynamically * Delegated Separation – Enhanced situational awareness in the air and on the ground * LowVisibility/CeilingApproach/Departure – Allowing operations with weather constraints with less ground infrastructure * Surface Operations – To increase safety in approach and departure * ATM Efficiencies – Improving the ATM process

Market

The Aircraft Electronics Association reports $1.73 billion avionics sales for the first three quarters of 2017 in

business Business is the practice of making one's living or making money by producing or buying and selling products (such as goods and services). It is also "any activity or enterprise entered into for profit." Having a business name does not sepa ...

and

general aviation General aviation (GA) is defined by the International Civil Aviation Organization (ICAO) as all civil aviation aircraft operations with the exception of commercial air transport or aerial work, which is defined as specialized aviation service ...

, a 4.1% yearly improvement: 73.5% came from North America, forward-fit represented 42.3% while 57.7% were

retrofit Retrofitting is the addition of new technology or features to older systems. Retrofits can happen for a number of reasons, for example with big capital expenditures like naval vessels, military equipment or manufacturing plants, businesses or go ...

s as the U.S. deadline of January 1, 2020 for mandatory ADS-B out approach.

Aircraft avionics

The cockpit of an aircraft is a typical location for avionic equipment, including control, monitoring, communication, navigation, weather, and anti-collision systems. The majority of aircraft power their avionics using 14- or 28‑volt DC electrical systems; however, larger, more sophisticated aircraft (such as airliners or military combat aircraft) have AC systems operating at 400 Hz, 115 volts AC. There are several major vendors of flight avionics, including

The Boeing Company 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 product ...

Panasonic Avionics Corporation Panasonic Avionics Corporation (PAC) designs, engineers, manufactures, sells and installs customized in-flight entertainment and communications devices to airlines worldwide. It is a subsidiary of Panasonic Corporation of North America, the princ ...

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 ...

(which now owns Bendix/King), Universal Avionics Systems Corporation,

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 Comp ...

(now Collins Aerospace),

Thales Group Thales Group () is a French multinational company that designs, develops and manufactures electrical systems as well as devices and equipment for the aerospace, defence, transportation and security sectors. The company is headquartered in Pari ...

, GE Aviation Systems,

Garmin Garmin Ltd. (shortened to Garmin, stylized as GARMIN, and formerly known as ProNav) is an American, Swiss-domiciled multinational technology company founded in 1989 by Gary Burrell and Min Kao in Lenexa, Kansas, United States, with headquar ...

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 ...

Parker Hannifin Parker Hannifin Corporation, originally Parker Appliance Company, usually referred to as just Parker, is an American corporation specializing in motion and control technologies. Its corporate headquarters are in Mayfield Heights, Ohio, in Greate ...

UTC Aerospace Systems UTC Aerospace Systems (UTAS) was one of the world’s largest suppliers of aerospace and defense products, headquartered in Charlotte, North Carolina, United States. The company was formed in August 2012 when parent United Technologies Corporation ...

(now Collins Aerospace),

Selex ES Selex ES was a subsidiary of Finmeccanica S.p.A., active in the electronics and information technology business, based in Italy and the UK, and formed in January 2013, following Finmeccanica's decision to combine its existing SELEX Elsag an ...

(now

Leonardo S.p.A. Leonardo S.p.A., formerly Leonardo-Finmeccanica and originally Finmeccanica, is an Italian multinational company specialising in aerospace, defence and security. Headquartered in Rome, Italy, the company has 180 sites worldwide. It is the eighth ...

), Shadin Avionics, and Avidyne Corporation. International standards for avionics equipment are prepared by the Airlines Electronic Engineering Committee (AEEC) and published by ARINC.

Communications

Communications connect the flight deck to the ground and the flight deck to the passengers. On‑board communications are provided by public-address systems and aircraft intercoms. The VHF aviation communication system works on the

airband Airband or aircraft band is the name for a group of frequencies in the VHF radio spectrum allocated to radio communication in civil aviation, sometimes also referred to as ''VHF'', or phonetically as ''"Victor"''. Different sections of the band ...

of 118.000 MHz to 136.975 MHz. Each channel is spaced from the adjacent ones by 8.33 kHz in Europe, 25 kHz elsewhere. VHF is also used for line of sight communication such as aircraft-to-aircraft and aircraft-to-ATC.

Amplitude modulation Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting messages with a radio wave. In amplitude modulation, the amplitude (signal strength) of the wave is varied in proportion to t ...

(AM) is used, and the conversation is performed in

simplex In geometry, a simplex (plural: simplexes or simplices) is a generalization of the notion of a triangle or tetrahedron to arbitrary dimensions. The simplex is so-named because it represents the simplest possible polytope in any given dimension. ...

mode. Aircraft communication can also take place using HF (especially for trans-oceanic flights) or satellite communication.

Navigation

Air navigation The basic principles of air navigation are identical to general navigation, which includes the process of planning, recording, and controlling the movement of a craft from one place to another. Successful air navigation involves piloting an air ...

is the determination of position and direction on or above the surface of the Earth. Avionics can use

satellite navigation A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows satellite navigation devices to determine their location (longitude, latitude, and altitude/elevation) to high pr ...

systems (such as

GPS The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...

and

WAAS The Wide Area Augmentation System (WAAS) is an air navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability. Essentia ...

inertial navigation system An inertial navigation system (INS) is a navigation device that uses motion sensors (accelerometers), rotation sensors (gyroscopes) and a computer to continuously calculate by dead reckoning the position, the orientation, and the velocity (dire ...

(INS), ground-based

radio navigation Radio navigation or radionavigation is the application of radio frequencies to determine a position of an object on the Earth, either the vessel or an obstruction. Like radiolocation, it is a type of radiodetermination. The basic principles a ...

systems (such as VOR or

LORAN LORAN, short for long range navigation, was a hyperbolic radio navigation system developed in the United States during World War II. It was similar to the UK's Gee system but operated at lower frequencies in order to provide an improved range u ...

), or any combination thereof. Some navigation systems such as GPS calculate the position automatically and display it to the flight crew on moving map displays. Older ground-based Navigation systems such as VOR or LORAN requires a pilot or navigator to plot the intersection of signals on a paper map to determine an aircraft's location; modern systems calculate the position automatically and display it to the flight crew on moving map displays.

Monitoring

The first hints of

glass cockpit A glass cockpit is an aircraft cockpit that features electronic (digital) flight instrument displays, typically large LCD screens, rather than the traditional style of analog dials and gauges. While a traditional cockpit relies on numerous me ...

s emerged in the 1970s when flight-worthy

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), pic ...

(CRT) screens began to replace electromechanical displays, gauges and instruments. A "glass" cockpit refers to the use of computer monitors instead of gauges and other analog displays. Aircraft were getting progressively more displays, dials and information dashboards that eventually competed for space and pilot attention. In the 1970s, the average aircraft had more than 100 cockpit instruments and controls.''Avionics: Development and Implementation'' by Cary R. Spitzer (Hardcover – December 15, 2006) Glass cockpits started to come into being with the Gulfstream G‑IV private jet in 1985. One of the key challenges in glass cockpits is to balance how much control is automated and how much the pilot should do manually. Generally they try to automate flight operations while keeping the pilot constantly informed.

Aircraft flight-control system

Aircraft have means of automatically controlling flight.

Autopilot An autopilot is a system used to control the path of an aircraft, marine craft or spacecraft without requiring constant manual control by a human operator. Autopilots do not replace human operators. Instead, the autopilot assists the operator' ...

was first invented by

Lawrence Sperry Lawrence Burst Sperry (21 December 1892, Chicago, Illinois, United States – December 13, 1923, English Channel) was an aviation pioneer who invented the autopilot and the artificial horizon. Biography He was the third son of the gyrocompa ...

during

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

to fly bomber planes steady enough to hit accurate targets from 25,000 feet. When it was first adopted by the U.S. military, a

engineer sat in the back seat with bolt cutters to disconnect the autopilot in case of emergency. Nowadays most commercial planes are equipped with aircraft flight control systems in order to reduce pilot error and workload at landing or takeoff.By Jeffrey L. Rodengen. . Published by Write Stuff Syndicate, Inc. in 1995. "The Legend of Honeywell." The first simple commercial auto-pilots were used to control heading and altitude and had limited authority on things like

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that sys ...

and

flight control A conventional fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight. Aircraft ...

surfaces. In

s, auto-stabilization was used in a similar way. The first systems were electromechanical. The advent of

and electro-actuated flight surfaces (rather than the traditional hydraulic) has increased safety. As with displays and instruments, critical devices that were electro-mechanical had a finite life. With safety critical systems, the software is very strictly tested.

Fuel Systems

Fuel Quantity Indication System (FQIS) monitors the amount of fuel aboard. Using various sensors, such as capacitance tubes, temperature sensors, densitometers & level sensors, the FQIS computer calculates the mass of fuel remaining on board. Fuel Control and Monitoring System (FCMS) reports fuel remaining on board in a similar manner, but, by controlling pumps & valves, also manages fuel transfers around various tanks. * Refuelling control to upload to a certain total mass of fuel and distribute it automatically. * Transfers during flight to the tanks that feed the engines. E.G. from fuselage to wing tanks * Centre of gravity control transfers from the tail (trim) tanks forward to the wings as fuel is expended * Maintaining fuel in the wing tips (to help stop the wings bending due to lift in flight) & transferring to the main tanks after landing * Controlling fuel jettison during an emergency to reduce the aircraft weight.

Collision-avoidance systems

To supplement

, most large transport aircraft and many smaller ones use a traffic alert and collision avoidance system (TCAS), which can detect the location of nearby aircraft, and provide instructions for avoiding a midair collision. Smaller aircraft may use simpler traffic alerting systems such as TPAS, which are passive (they do not actively interrogate the

transponder In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight tran ...

s of other aircraft) and do not provide advisories for conflict resolution. To help avoid controlled flight into terrain ( CFIT), aircraft use systems such as ground-proximity warning systems (GPWS), which use radar altimeters as a key element. One of the major weaknesses of GPWS is the lack of "look-ahead" information, because it only provides altitude above terrain "look-down". In order to overcome this weakness, modern aircraft use a terrain awareness warning system ( TAWS).

Flight recorders

Commercial aircraft cockpit data recorders, commonly known as "black boxes", store flight information and audio from the

cockpit A cockpit or flight deck is the area, usually near the front of an aircraft or spacecraft, from which a pilot controls the aircraft. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls that ena ...

. They are often recovered from an aircraft after a crash to determine control settings and other parameters during the incident.

Weather systems

Weather systems such as

weather radar Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.). Modern weather radars are mostly pulse ...

(typically Arinc 708 on commercial aircraft) and

lightning detector A lightning detector is a device that detects lightning produced by thunderstorms. There are three primary types of detectors: ''ground-based'' systems using multiple antennas, ''mobile systems'' using a direction and a sense antenna in the same l ...

s are important for aircraft flying at night or in

instrument meteorological conditions In aviation, instrument meteorological conditions (IMC) is a flight category that describes weather conditions that require pilots to fly primarily by reference to instruments, and therefore under instrument flight rules (IFR), rather than by o ...

, where it is not possible for pilots to see the weather ahead. Heavy precipitation (as sensed by radar) or severe

turbulence In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between ...

(as sensed by lightning activity) are both indications of strong convective activity and severe turbulence, and weather systems allow pilots to deviate around these areas. Lightning detectors like the Stormscope or Strikefinder have become inexpensive enough that they are practical for light aircraft. In addition to radar and lightning detection, observations and extended radar pictures (such as

NEXRAD NEXRAD or Nexrad (Next-Generation Radar) is a network of 160 high-resolution S-band Doppler weather radars operated by the National Weather Service (NWS), an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United S ...

) are now available through satellite data connections, allowing pilots to see weather conditions far beyond the range of their own in-flight systems. Modern displays allow weather information to be integrated with moving maps, terrain, and traffic onto a single screen, greatly simplifying navigation. Modern weather systems also include wind shear and turbulence detection and terrain and traffic warning systems. In‑plane weather avionics are especially popular in Africa,

India India, officially the Republic of India ( Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the ...

, and other countries where air-travel is a growing market, but ground support is not as well developed.

Aircraft management systems

There has been a progression towards centralized control of the multiple complex systems fitted to aircraft, including engine monitoring and management. Health and usage monitoring systems (HUMS) are integrated with aircraft management computers to give maintainers early warnings of parts that will need replacement. The integrated modular avionics concept proposes an integrated architecture with application software portable across an assembly of common hardware modules. It has been used in fourth generation jet fighters and the latest generation of airliners.

Mission or tactical avionics

Military aircraft A military aircraft is any fixed-wing or rotary-wing aircraft that is operated by a legal or insurrectionary armed service of any type. Military aircraft can be either combat or non-combat: * Combat aircraft are designed to destroy enemy equi ...

have been designed either to deliver a weapon or to be the eyes and ears of other weapon systems. The vast array of sensors available to the military is used for whatever tactical means required. As with aircraft management, the bigger sensor platforms (like the E‑3D, JSTARS, ASTOR, Nimrod MRA4, Merlin HM Mk 1) have mission-management computers. Police and EMS aircraft also carry sophisticated tactical sensors.

Military communications

While aircraft communications provide the backbone for safe flight, the tactical systems are designed to withstand the rigors of the battle field. UHF, VHF Tactical (30–88 MHz) and SatCom systems combined with ECCM methods, and

cryptography Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adve ...

secure the communications. Data links such as Link 11, 16, 22 and BOWMAN, JTRS and even

TETRA Terrestrial Trunked Radio (TETRA; formerly known as Trans-European Trunked Radio), a European standard for a trunked radio system, is a professional mobile radio and two-way transceiver specification. TETRA was specifically designed for use by go ...

provide the means of transmitting data (such as images, targeting information etc.).

Radar

Airborne

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, ships, spacecraft, guided missiles, motor vehicles, ...

was one of the first tactical sensors. The benefit of altitude providing range has meant a significant focus on airborne radar technologies. Radars include

(AEW),

anti-submarine warfare Anti-submarine warfare (ASW, or in older form A/S) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms, to find, track, and deter, damage, or destroy enemy submarines. Such operations are typi ...

(ASW), and even

( Arinc 708) and ground tracking/proximity radar. The military uses radar in fast jets to help pilots fly at low levels. While the civil market has had weather radar for a while, there are strict rules about using it to navigate the aircraft.

Sonar

Dipping sonar fitted to a range of military helicopters allows the

to protect shipping assets from submarines or surface threats. Maritime support aircraft can drop active and passive sonar devices (

sonobuoy A sonobuoy (a portmanteau of sonar and buoy) is a relatively small buoy – typically diameter and long – expendable sonar system that is dropped/ejected from aircraft or ships conducting anti-submarine warfare or underwater acoustic resea ...

s) and these are also used to determine the location of enemy submarines.

Electro-optics

Electro-optic systems include devices such as the

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 inform ...

(HUD),

forward looking infrared 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 ...

(FLIR),

infrared search and track An infrared search and track (IRST) system (sometimes known as infrared sighting and tracking) is a method for detecting and tracking objects which give off infrared radiation, such as the infrared signatures of jet aircraft and helicopters. IR ...

and other passive infrared devices (

Passive infrared sensor A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors. PIR sensors are commonly used in security alarms ...

). These are all used to provide imagery and information to the flight crew. This imagery is used for everything from search and rescue to

navigational aid Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...

s and

target acquisition Target acquisition is the detection and identification of the location of a target in sufficient detail to permit the effective employment of lethal and non-lethal means. The term is used for a broad area of applications. A "target" here is an e ...

ESM/DAS

Electronic support measures and defensive aids systems are used extensively to gather information about threats or possible threats. They can be used to launch devices (in some cases automatically) to counter direct threats against the aircraft. They are also used to determine the state of a threat and identify it.

Aircraft networks

The avionics systems in military, commercial and advanced models of civilian aircraft are interconnected using an avionics databus. Common avionics databus protocols, with their primary application, include: *

Aircraft Data Network Aircraft Data Network (ADN) is a concept introduced by the Airlines Electronics Engineering Committee (AEEC) in the ARINC 664 Specification. The specification proposes data networking standards recommended for use in commercial aircraft installat ...

( ADN): Ethernet derivative for Commercial Aircraft * Avionics Full-Duplex Switched Ethernet (AFDX): Specific implementation of ARINC 664 ( ADN) for Commercial Aircraft *

ARINC 429 ARINC 429, "Mark33 Digital Information Transfer System (DITS)," is also known as the Aeronautical Radio INC. (ARINC) technical standard for the predominant avionics data bus used on most higher-end commercial and transport aircraft. It defines the ...

: Generic Medium-Speed Data Sharing for Private and Commercial Aircraft * ARINC 664: See ADN above * ARINC 629: Commercial Aircraft (

Boeing 777 The Boeing 777, commonly referred to as the Triple Seven, is an American long-range wide-body airliner developed and manufactured by Boeing Commercial Airplanes. It is the world's largest twinjet. The 777 was designed to bridge the gap bet ...

) * ARINC 708: Weather Radar for Commercial Aircraft * ARINC 717: Flight Data Recorder for Commercial Aircraft * ARINC 825:

CAN bus A Controller Area Network (CAN bus) is a robust vehicle bus standard designed to allow microcontrollers and devices to communicate with each other's applications without a host computer. It is a message-based protocol, designed originally for ...

for commercial aircraft (for example

Boeing 787 The Boeing 787 Dreamliner is an American wide-body jet airliner developed and manufactured by Boeing Commercial Airplanes. After dropping its unconventional Sonic Cruiser project, Boeing announced the conventional 7E7 on January 29, 2003, ...

and

Airbus A350 The Airbus A350 is a flight length, long-range, wide-body aircraft, wide-body twinjet, twin-engine jet airliner developed and produced by Airbus Commercial Aircraft, Airbus. The first A350 design proposed by Airbus in 2004, in response to ...

) * Commercial Standard Digital Bus * IEEE 1394b: Military Aircraft *

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 wit ...

: Military Aircraft *

MIL-STD-1760 MIL-STD-1760 Aircraft/Store Electrical Interconnection System defines a standardized electrical interface between a military aircraft and its carriage stores. Carriage stores range from weapons, such as GBU-31 JDAM, to pods, such as AN/AAQ-14 L ...

: Military Aircraft * TTP – Time-Triggered Protocol:

Airbus A380 The Airbus A380 is a large wide-body airliner that was developed and produced by Airbus. It is the world's largest passenger airliner and only full-length double-deck jet airliner. Airbus studies started in 1988, and the project was annou ...

, Fly-By-Wire Actuation Platforms from Parker Aerospace

Notes

External links

Avionics in Commercial AircraftAircraft Electronics Association (AEA)''Pilot's Guide to Avionics''The Avionic Systems Standardisation CommitteeAviation Today Avionics magazineRAES Avionics homepage
{{Authority control Aircraft instruments Spacecraft components Electronic engineering