PRIMUSr 880 Digital Weather Radar System

DThe antenna size used on the aircraft alters the best tilt settings by about 1_. However, tilt management is the same for either size, as shown in figure 5- 16.

10- IN. ANTENNA

HAS 10 BEAM 12- IN. ANTENNA HAS 7.9 BEAM

18- IN. ANTENNA HAS 5.6 BEAM

24- IN. ANTENNA HAS 4.2 BEAM

Antenna Size and Impact on Tilt Management

Figure 5- 16

NOTE: A 10- inch antenna is shown for illustration purposes only.

DSome of the rules of thumb are described below and shown in figure 5- 17.

-A 1_ look down angle looks down 100 ft per mile

-Bottom of beam is 1/2 beam width below tilt setting

-A 12- inch antenna grazes the ground at 100 NM if set to 0_ tilt at 40,000 ft.

TILT

BEAM WIDTH

AD- 35702@

Rules of Thumb

Figure 5- 17

A28- 1146- 102- 00

Radar Facts

 

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Honeywell 880 manual Antenna Size and Impact on Tilt Management, Rules of Thumb