空中领航学(E06).ppt

北京航空航天大学飞行学院
空中领航学
Air Navigation
课件制作
课程讲授
王惠民
NM
340M
A correctly tuned ADF indicates the direction of a selected NDB from the aircraft.
NDB-bination
The NDB (non-directional beacon) is a ground radio transmitter; and
the ADF (automatic direction finder) is a receiver in the aircraft.
The pilot is able to determine with reference to the aircraft ic heading a position line between the aircraft and NDB.
The NDB-ADF system is used for the following
purposes:
• orientation (where am I?);
• en route navigation (tracking from
point to point);
• holding over specified points; and
• instrument approaches.
Non-directional beacons are simple ground-based transmitters that radiate an omni-directional (all directions) signal. Nearly all NDBs in Australia operate on frequencies between 200 kHz and 400 kHz.
Most NDBs are primarily short-distance navigation aids, useful for distances less than 200 nm.
Non-Directional Beacon (NDB)
Non-Directional Beacon (NDB)
Two types of NDB transmission antennas.
The transmitter power of most NDBs is between 100 W and 3,000W.
Most NDBs are installed in pairs, with a main and standby in case of failure, and are extremely reliable aids.
Civil Aviation Safety Authority personnel at nearby aerodromes monitor the NDBs within range, but NDBs in remote areas should be monitored by pilots and any faults reported by radio to allow early rectification.
NDB Reliability
NDB frequencies, ident codes and geographical positions are found in the following publications:
• En Route Supplement Australia (ERSA);
• en route charts (ERC);
• visual navigation charts (VNC); and
• visual terminal charts (VTC).
Where to Find Details of an NDB
Detailed information for each NDB is presented in the ERSA.
Rated coverage
Position
Ident
Ident
Ident
Frequency
212 KHz
NDB details on an ERC-L.
NDB details on a VTC.