An integrated standby instrument system (ISIS) is an electronic aircraft instrument. It is intended to serve as backup in case of a failure of the standard

glass cockpit A glass cockpit is an aircraft cockpit that features an array of electronic (digital) flight instrument display device, displays, typically large liquid-crystal display, LCD screens, rather than traditional Analog device, analog dials and gauges ...

instrumentation, allowing pilots to continue to receive key flight-related information. Prior to the use of ISIS, this was performed by individual redundant mechanical instrumentation instead. Such systems have become common to be installed in various types of aircraft, ranging from

airliners An airliner is a type of airplane for transporting passengers and air cargo. Such aircraft are most often operated by airlines. The modern and most common variant of the airliner is a long, tube shaped, and jet powered aircraft. The largest o ...

helicopter A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and ...

s and smaller

general aviation General aviation (GA) is defined by the International Civil Aviation Organization (ICAO) as all civil aviation aircraft operations except for commercial air transport or aerial work, which is defined as specialized aviation services for other ...

aircraft. While it is common for new-built aircraft to be outfitted with ISIS, numerous operators have opted to have their fleets retrofitted with such apparatus as well. Typically there are 3 instruments: an airspeed indicator, an altimeter and an attitude indicator. Cessna Citation Mustang glass cockpit

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An ISIS is designed to combine the functions of separate equivalent mechanical instruments that had previously been included as backup in such cockpits, including

altimeter An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level. The measurement of altitude is called altimetry, which is related to the term bathymetry, the measurement of depth under water. Ty ...

airspeed indicator The airspeed indicator (ASI) or airspeed gauge is a flight instrument indicating the airspeed of an aircraft in kilometres per hour (km/h), knots (kn or kt), miles per hour (MPH) and/or metres per second (m/s). The recommendation by ICAO is to u ...

, and

attitude indicator The attitude indicator (AI), also known as the gyro horizon or artificial horizon, is a flight instrument that informs the pilot of the aircraft Orientation (geometry), orientation relative to Earth's horizon, and gives an immediate indication of ...

. Various aspects of ISIS are defined by its function of being a backup to conventional instrumentation. In accordance with this principal, it has been designed to operate with a high level of availability and reliability, as well as being as independent as possible from the aircraft's primary instrumentation and sensors alike. It is commonplace for an ISIS to work in conjunction with provisions for auxiliary power (typically a battery unit), as well as harnessing embedded sensors for its readings wherever possible. When all onboard instrumentation is performing normally, the readings indicated by an ISIS are identical to that of the

primary flight display A primary flight display or PFD is a modern aircraft instrument dedicated to flight information. Much like multi-function displays, primary flight displays are built around a Liquid-crystal display or CRT display device. Representations of ol ...

. Advantages presented by ISIS over traditional systems include improved safety, greater ease of operation, and reduced operating costs. A number of aircraft have been produced with relatively sophisticated integrated standby systems which may include additional functions. For example, the

Rockwell Collins Rockwell Collins, Inc. 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 Radi ...

Pro Line 21 flight deck, which is fitted to aircraft such as the Cessna Citation XLS+

business jet A business jet, private jet, or bizjet is a jet aircraft designed for transporting small groups of people, typically business executives and high-ranking coworker, associates. Business jets are generally designed for faster air travel and more ...

, features a standby navigation display and engine gauges.

Thales Group Thales S.A., Trade name, trading as Thales Group (), is a French multinational corporation, multinational aerospace and defence industry, defence corporation specializing in electronics. It designs, develops and manufactures a wide variety of aer ...

produce their own ISIS, which is installed on the

Airbus A320 The Airbus A320 family is a series of narrow-body airliners developed and produced by Airbus. The A320 was launched in March 1984, Maiden flight, first flew on 22 February 1987, and was introduced in April 1988 by Air France. The first membe ...

narrow-body A narrow-body aircraft or single-aisle aircraft is an airliner arranged along a single aisle, permitting up to 6-abreast airline seat, seating in a aircraft cabin, cabin less than in width. In contrast, a wide-body aircraft is a larger airliner ...

and

Airbus A330 The Airbus A330 is a wide-body airliner developed and produced by Airbus. Airbus began developing larger A300 derivatives in the mid–1970s, giving rise to the A330 twinjet as well as the Airbus A340 quadjet, and launched both designs along ...

wide-body airliner A wide-body aircraft, also known as a twin-aisle aircraft and in the largest cases as a jumbo jet, is an airliner with a fuselage wide enough to accommodate two passenger aisles with seven or more seats abreast. The typical fuselage diameter is . ...

s amongst other aircraft; it allowed for one single instrument to replace four standby instruments that had been traditionally used. Thales also produced an Integrated Electronic Standby Instrument (IESI) dedicated for use on

s; in excess of 6,000 such units have reportedly been sold as of July 2020. Another such system is manufactured by

L3Harris Technologies L3Harris Technologies, Inc. is an American technology company, defense contractor, and information technology service (economics), services provider that produces products for command and control systems, wireless equipment, tactical radios, avi ...

, intended for both helicopters and

purposes. Additional companies specialising in avionics, such as

GE Aviation General Electric Company, doing business as GE Aerospace, is an American aircraft engine supplier that is headquartered in Evendale, Ohio, outside Cincinnati. It is the legal successor to the original General Electric Company founded in 1892, wh ...

Smiths Group Smiths Group plc is a British, Multinational corporation, multinational, diversified engineering business headquartered in London, England. It operates in over 50 countries and employs 15,000 staff. Smiths Group is listed on the London Stock Ex ...

, and

Meggitt Parker Meggitt (legally Meggitt Ltd) is a British international company specialising in components and sub-systems for the aerospace, defence and selected energy markets. It was listed on the London Stock Exchange and was a constituent of the F ...

, have also marketed ranges of standby instrumentation using both standalone and ISIS-compliance principles. Several companies have produced

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling discl ...

able innovations related to ISIS, including large aerospace players such as Airbus Group. In addition to such technology being adopted upon new-build aircraft, several operators have opted to retrofit their existing aircraft fleets with current generation ISIS, such as UPS's

Airbus A300 The Airbus A300 is Airbus' first production aircraft and the world's first Twinjet, twin-engine, double-aisle Wide-body aircraft, (wide-body) airliner. It was developed by ''Airbus Industrie GIE'', now merged into Airbus SE, and manufactured f ...

freighters. Along these lines, Rockwell Collins developed a retrofit package for the

Boeing 757 The Boeing 757 is an American Narrow-body aircraft, narrow-body airliner designed and built by Boeing Commercial Airplanes. The then-named 7N7, a twinjet successor for the trijet Boeing 727, 727, received its first orders in August 1978. The ...

and

Boeing 767 The Boeing 767 is an American wide-body airliner developed and manufactured by Boeing Commercial Airplanes. The aircraft was launched as the 7X7 program on July 14, 1978, the prototype first flew on September 26, 1981, and it was certified ...

that incorporates ISIS. During the 2010s, the cost of performing such cockpit display retrofits reportedly dropped substantially.

References

External links

Industry Scan via aviationtoday.com

Chapter 2: Electronic Flight Instruments via faa.gov

Electronic Flight Instrument System via skybrary.aero
{{Flight instruments Aircraft instruments

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See also

References

External links