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Integrated standby instrument system for airliner, helicopter and UAM

As a world market leader in conventional instrumentation, Thales has combined its expertise in both active-matrix LCD technology and solid-state sensors, including inertial and pressure components, to propose a self-contained family of Integrated Electronic Standby Instrument (IESI) products, also known as Integrated Standby Instrument System (ISIS).

With more than 40,000 systems delivered since the creation of the product in 1999 and already more than 250 million flight hours, the Thales IESI is configurable for transport and regional aircraft, business aircraft, civil and military helicopters, mission aircraft applications, in linefit and retrofit.

The Thales IESI is flying on board major civil aircraft programs including the A320 family and Boeing 737.

Capitalizing on this unparalleled experience, Thales offers more proof of reliability than any other manufacturer and continues to set the standards of safety in the industry. The Thales IESI is the first system of its kind that fully complies with DO-254 and DO-178 B DAL B standards, further increasing the level of intrinsic safety. 

Low power consumption instrument

The Thales IESI features extended graphic generation capabilities for fast symbology customization, new transparent symbology, colour control and easy product customization. LED backlighting significantly reduces power consumption while offering high luminosity capabilities, accurate low luminosity control with quick response times, and improved homogeneity.

Compact standby instrument with low maintenance costs

Housed in a single 3-ATI mounting, Thales IESI provides three essential back-up functions – artificial horizon, altimeter and airspeed indicator – all in one place. With three times more functionality in a single piece of equipment, Thales IESI increases reliability while cutting direct maintenance costs compared to other standby instrument solutions.

Integrated electronic standby instrument – how does it work?

The incorporation of the integrated electronic standby instrument (IESI) into the glass cockpit of the majority of aircraft is a major innovation. As its name suggests, the IESI combines – both on a functional level and in terms of display via an LCD screen – the standby instruments that provide pilots with minimum essential data in the event of a general failure of the other cockpit equipment. 

Previously, cockpits were equipped with three individual standby instruments in the form of an attitude indicator, altimeter, and airspeed indicator. The integrated electronic standby instrument comprises, in a single unit, an inertial navigation unit with linked components, and silicon pressure sensors connected to two airspeed indicators: a Pitot tube and a static pressure sensor, which together determine the real speed of the aircraft in relation to the ambient air.

The physical variables measured by an aircraft’s Pitot tubes and static pressure sensors are normally converted into digital information by air data modules (ADMs) and processed by onboard computers. In the case of the integrated electronic standby instrument, however, the physical variable measured by one of the static sensors is not digitised, but transmitted directly to the IESI, positioned in the middle of the central. The pressure measured by a Pitot tube is also sent directly to the IESI’s airspeed indicator.