Horizontal situation indicator
The Horizontal Situation Indicator, HSI is an instrument for radio navigation of aircraft . It is used to display flight paths and is mainly used as a backup for other, more modern navigation systems, such as the HSD (Horizontal Situation Display).
Functions of the instrument
It is a combination instrument of VOR receiver , gyrocompass ( Gyrosyn ) and glide slope for the instrument landing system , ILS , combines the various navigation information in a single device and thereby the funknavigatorische work in the cockpit noticeably easier. Compared to separate instruments, the presentation of the HSI provides a faster and more intuitive overview of the spatial relationships and allows the more precise execution of complex instrument flight procedures, e.g. B. of waiting procedures and instrument landing approaches.
The HSI is used in particular in aircraft that are often flown according to instrument flight rules . Some aviation GPS receivers also have an HSI display, but this is limited compared to systems that are permanently installed in the aircraft.
construction
The device is linked to the gyro compass, VOR receiver, glide slope, and autopilot. The glide slope indicator appears as a small yellow triangle on one or both sides.
In contrast to the normal VOR indicator, the HSI has a degree disk that is tracked as a gyro compass, which therefore rotates with the changing course. On the HSI , your own aircraft is miniaturized in the middle of the instrument. VOR or ILS localizers are shown in relation to the miniature aircraft.
Interpretation of the ad
The HSI offers a bird's eye view for navigation. It gives the course, heading and bearing information related to a VOR, control points, runways, or marker points.
With a normal VOR display, RIGHT and LEFT as well as TO / FROM must be interpreted with reference to the set course. If the HSI is set to a VOR station, right and left are also real right and left. TO / FROM is simply represented by a needle display. Your own position (aircraft) is in the middle. If the arrow points upwards (front), it means (TO), if the arrow points backwards (down), it means FROM.
literature
- US Department of Transportation, Federal Aviation Administration - Instrument Flying Handbook , FAA-H-8083-15B, 2012
- Rod Machados's - Instrument Pilot's Survival Manual 1998, ISBN 0-9631229-0-8
- Peter Dogan - Instrument Flight Training Manual 1999, ISBN 0916413128
- Jeppesen Sanderson - Privat Pilot Manual 2001, ISBN 0-88487-238-6
- Wolfgang Kühr - The Private Airplane Pilot , Technology II, Volume 3 1981, ISBN 392127009X