OPERATING MANUAL FLARM COLLISION WARNING UNIT
Version 4.06E
Page 10 of 12
March 28, 2009
12.
Obstacle Warnings
The standard obstacle data bank (as of Jan 2009) has about 33,000 coordinates locating about
11,000 Alpine obstacles
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. This data bank is loaded by FLARM at manufacture; subsequently the user may
upload but not alter up-dated information via a PC. Special data banks, corrections and amendments can be
reported to us.
The FLARM display flashes when there is warning of obstacles. The warning always relates to obstacles
straight in-line with the current flight heading. In other words there is no horizontal or vertical bearing given to
the obstacle. The threat level depends upon the time remaining to impact; the flash and beep frequency
increases with reducing distance from the obstacle. The display is refreshed every second.
A warning is given if an aircraft flies under a cable or power line.
An acoustic warning (beep) is given at the same time as the flashing fixed obstacle warning. The time
between warning and possible collision is brief, just a few seconds. However, warnings are given of fixed
obstacles earlier than those for other aircraft.
Obstacles are indicated as follows:
A toggling pair of two LED’s is shown, with the toggle frequency
depending on the threat.
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For details on the data sources and status, consult the ‚Obstacle Data Format Specifications’ manual.
Neither FLARM Technology nor these organisations accept any responsibility for the accuracy, completeness or up-to-date
status of the data or any direct or indirect damage resulting from using such data. Official data sources only collect data
which have been reported by those who own, construct or operate constructions which represent an obstacle, and do not
check these reports.
