Справочник Пользователя для Garmin gns 500w

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190-00356-00 Rev E

Flying the LP Approach

An LP approach is flown the same as an LPV

approach, except that vertical guidance is not provided. 
Angular scaling is similar to a localizer approach. Most 
LP approaches have step down altitudes associated with 
them. 

1.  Within 30 nautical miles of the destination, the 

400W-series unit switches from en route mode 
to terminal mode and the CDI scale transitions 
from 2.0 to 1.0 nautical miles, full scale deflec-
tion. 

2.  As you approach the IAF, a turn direction mes-

sage appears on the bottom of the screen. 

3.  As the distance (DIST) to the IAF approaches 

zero, the message is replaced by a time to turn 
advisory that counts down 10 seconds prior to 
the turn. 

4.  As you approach the FAF, the 400W-series 

unit will begin to automatically rescale in an 
angular fashion. This will allow the LP approach 
to be flown in the same fashion as a standard 
localizer approach. At 2.0 nautical miles from 
the FAF, CDI scaling is tightened from up to 
either 2° or 0.3 nautical miles, full scale deflec-
tion, whichever is smaller. 

5.  Sixty seconds prior to reaching the FAF, the 

400W-series unit will check the required 
Horizontal Alarm Limit (HAL) to ensure the GPS 
position integrity is within limits to complete 
the LP non-precision approach. In the event 
the HAL limits are exceeded, the approach will 
be downgraded, when available, indicated by 

“LNAV” on the moving map, otherwise the 
approach will be aborted. A message will note 
that the approach is downgraded and the NAV 
indicator will be flagged. You may continue the 
approach using LNAV non-precision minimums 
if there are LNAV minimums for this approach. 
In the rare event the GPS HAL limits cannot 
meet non-precision limits, the 400W-series unit 
will notify the pilot with a message to abort the 
approach. The 400W-series unit will revert to 
terminal limits of 1.0 NM to support navigation 
to the missed approach. 

6.  As you cross the FAF, the destination sequences 

to the MAP. With the needle on the external CDI 
(or HSI) centered, fly toward the MAP, observing 
the altitude minimums dictated by the approach 
plate. 

7. When viewing the Map Page, you’ll note that 

the final course segment is displayed in ma-
genta (the active leg of the flight plan always 
appears in magenta). 

8.  As you approach the MAP, a waypoint message 

(“Arriving at Waypoint”) appears on the bottom 
of the screen. 

9.  At the MAP initiate the missed approach, if 

necessary. Once the 400W-series unit crosses 
the MAP sequencing will be suspended. Prepare 

the aircraft for missed approach operation. 

Press the OBS key to sequence to the Missed 
Approach procedure. 

 

NOTE: For missed approaches with heading legs, 
fly manually until the first active course leg is 
reached, as described in earlier sections. 

10. Fly the guidance provided by the 400W-series 

unit to the MAHP and hold.