A flight recorder is an electronic recording device placed in an aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft 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 engines.Although...
for the purpose of facilitating the investigation of an aircraft accident
Aviation accidents and incidents
An aviation accident is defined in the Convention on International Civil Aviation Annex 13 as an occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight and all such persons have disembarked, in which a...
or incident. For this reason, flight recorders are required to be capable of surviving the conditions likely to be encountered in a severe aircraft accident. They are typically specified to withstand an impact of 3400 g
The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...
and temperatures of over 1,000 °C (1,832 °F) (as required by EUROCAE ED-112). There are two common types of flight recorder, the flight data recorder
Flight data recorder
A flight data recorder is an electronic device employed to record any instructions sent to any electronic systems on an aircraft. It is a device used to record specific aircraft performance parameters...
(FDR) and the cockpit voice recorder
Cockpit voice recorder
A cockpit voice recorder , often referred to as a "black box", is a flight recorder used to record the audio environment in the flight deck of an aircraft for the purpose of investigation of accidents and incidents...
(CVR). In some cases, the two recorders may be combined in a single FDR/CVR unit.
Since the 1970s most large civil jet transports have been additionally equipped with a "quick access recorder
Quick access recorder
A quick access recorder is an airborne flight data recorder designed to provide quick and easy access to raw flight data, through means such as USB or cellular network connections and/or the use of standard flash memory cards...
" (QAR). This records data on a removable storage medium. Access to the FDR and CVR is necessarily difficult because of the requirement that they survive an accident. They also require specialized equipment to read the recording. The QAR recording medium is readily removable and is designed to be read by equipment attached to a standard desktop computer. In many airlines the quick access recordings are scanned for 'events', an event being a significant deviation from normal operational parameters. This allows operational problems to be detected and eliminated before an accident or incident results.
Many modern aircraft systems are digital or digitally controlled
Fly-by-wire 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 computers determine how to move the actuators at each control...
. Very often the digital system will include Built-In Test Equipment which records information about the operation of the system. This information may also be accessed to assist with the investigation of an accident or incident.
SpecificationsEUROCAE ED-112 (Minimum Operational Performance Specification for Crash Protected Airborne Recorder Systems) defines the minimum specification to be met for all aircraft requiring flight recorders for recording of flight data, cockpit audio, images and CNS/ATM digital messages and used for investigations of accidents or incidents. When issued in March 2003 ED-112 superseded previous ED-55 and ED-56A that were separate specifications for FDR and CVR. FAA TSO
Technical Standard Order
A Technical Standard Order is a minimum performance standard issued by the United States Federal Aviation Administration for specified materials, parts, processes, and appliances used on civil aircraft. Articles with TSO design approval are eligible for use on the United States type certificated...
s for FDR and CVR reference ED-112 for characteristics common to both types.
In order to facilitate recovery of the recorder from an aircraft accident site they are required to be coloured bright yellow or orange with reflective surfaces. All are lettered "FLIGHT RECORDER DO NOT OPEN" on one side in English and the same in French on the other side. To assist recovery from submerged sites they must be equipped with an underwater locator beacon
Underwater locator beacon
An underwater locator beacon or underwater acoustic beacon is a device fitted to aviation flight recorders such as the cockpit voice recorder and flight data recorder. ULBs are also sometimes required to be attached directly to an aircraft fuselage...
which is automatically activated in the event of an accident.
HistoryAs with many successful devices, probably no single person could be credited with the invention of the flight recorder. One of the earliest and proven attempts was made by François Hussenot
François Hussenot was a French engineer, credited with the invention of one of the early forms of the flight data recorder.He attended the Ecole Polytechnique from 1930 to 1932...
and Paul Beaudouin in 1939 at the Marignane
Marignane is a commune in the Bouches-du-Rhône department in the Provence-Alpes-Côte d'Azur region in southern France.-Geography:It is a component of the metropolitan Marseille Provence Métropole, and the largest suburb of the city of Marseille...
flight test center, France; they were essentially photograph-based flight recorders since the record was made on a scrolling photographic film
Photographic film is a sheet of plastic coated with an emulsion containing light-sensitive silver halide salts with variable crystal sizes that determine the sensitivity, contrast and resolution of the film...
. The latent image
A latent image on photographic film is an invisible image produced by the exposure of the film to light. When the film is developed, the area that was exposed darkens and forms a visible image...
was made by a thin ray of light deviated by a mirror tilted according to the magnitude of the data to record (altitude, speed, etc). Since the inside of the recorder was pitch black, this may be the origin of the "black box
Black Box (transportation)
The term black box is a placeholder name used casually to refer to a collection of several different recording devices used in transportation: the flight recorders in aircraft, the event recorder in railway locomotives, the event data recorder in automobiles, message case in ships, and other...
" name, often used as a synonym for a flight recorder. In 1947, Hussenot founded the Société Française des Instruments de Mesure with Beaudouin and another associate, so as to market his invention, which was also known as the "hussenograph"; the SFIM went on becoming a successful equipment company and a major flight recorder supplier, and is today part of the Safran
Safran is a French conglomerate involved in defense, aerospace propulsion and equipment, and security. It is the result of a merger between the propulsion and aerospace equipment group SNECMA and the defense conglomerate SAGEM. Its headquarters are located in Paris.The name Safran, literally...
The first modern flight recorder called "Mata Hari" was founded 1942 by Finnish aviation engineer Veijo Hietala. This black high-tech mechanical box was able to record all important aviation details during test flight of WWII fighters Finnish army repaired or built in their main aviation factory Tampere, Finland. The black box is in museum Vapriikki, Tampere, Finland.
In 1953, Australian engineer David Warren
David Warren (inventor)
David Ronald de Mey Warren AO was an Australian scientist, best known for inventing and developing the flight data recorder and cockpit voice recorder .-Early life:...
conceived a device that would record not only the instruments reading, but also the cockpit voices, when working with the Defence Science and Technology Organisation
Defence Science and Technology Organisation
The Defence Science and Technology Organisation is a branch of the Australian Department of Defence which researches and develops technologies for use in the Australian defence industry....
s' Aeronautical Research Laboratory (Melbourne, Australia). He built the first prototype in 1958. It was not until after the 1956 Grand Canyon mid-air collision
1956 Grand Canyon mid-air collision
The 1956 Grand Canyon mid-air collision occurred on Saturday, June 30, 1956 at 10:30 AM Pacific Standard Time when a United Airlines passenger airliner struck a Trans World Airlines airliner over the Grand Canyon in Arizona, resulting in the crash of both planes and 128 fatalities...
that black boxes of any kind were installed on commercial airplanes. In 1965 black boxes were redesigned and moved to the rear of airplanes to improve the probability of successful data retrieval after a crash. To facilitate their being found after a crash, they are bright orange, as shown in the picture, but the inaccurate nickname remains.
Cockpit image recorder recommendationThe U.S. National Transportation Safety Board
National Transportation Safety Board
The National Transportation Safety Board is an independent U.S. government investigative agency responsible for civil transportation accident investigation. In this role, the NTSB investigates and reports on aviation accidents and incidents, certain types of highway crashes, ship and marine...
has asked for the installation of cockpit image recorders in large transport aircraft to provide information that would supplement existing CVR and FDR data in accident investigations. They also recommended image recorders be placed into smaller aircraft that are not required to have a CVR or FDR. The rationale is that what is seen on an instrument by the pilots of an aircraft is not necessarily the same as the data sent to the display device. This is particularly true of aircraft equipped with electronic displays (CRT
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
Liquid crystal display
A liquid crystal display is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals . LCs do not emit light directly....
). A mechanical instrument is likely to preserve its last indication but this is not the case with an electronic display.
Such systems, estimated to cost less than $8,000 installed, typically consist of a camera and microphone located in the cockpit to continuously record cockpit instrumentation, the outside viewing area, engine sounds, radio communications, and ambient cockpit sounds. As with conventional CVRs and FDRs, data from such a system is stored in a crash-protected unit to ensure survivability.
- Annex: Acronyms and abbreviations in avionics
- Black box (transportation)Black Box (transportation)The term black box is a placeholder name used casually to refer to a collection of several different recording devices used in transportation: the flight recorders in aircraft, the event recorder in railway locomotives, the event data recorder in automobiles, message case in ships, and other...
- Charlie Victor RomeoCharlie Victor RomeoCharlie Victor Romeo is a 1999 play whose script consists of almost-verbatim transcripts from six real-life aviation accidents and incidents. "Charlie Victor Romeo," or CVR, derived from the NATO phonetic alphabet, is aviation lingo for cockpit voice recorder...
- Event recorderEvent recorderA Train event recorder is similar to the flight data recorder found on aircraft. It records data about the operation of train controls and performance in response to those controls and other train control systems.Data storage is provided by magnetic tape, battery-backed RAM and, most recently,...
- Voyage Data RecorderVoyage Data Recorderthumb|A fixed Data Capsule of VDR mounted on a [[container ship]].Voyage Data Recorder, or VDR, is a data recording system designed for all vessels required to comply with the IMO's International Convention SOLAS Requirements in order to collect data from various sensors on board the vessel...
- Distress radiobeacon
- List of unrecovered flight recorders
- Korean Air Lines Flight 007