GPS Arcing Approach

T-6A INSTRUMENT NAVIGATION

CHAPTER EIGHT

WARNING

The GPS always displays distance TO the active waypoint, which

is different than the DME distance FROM the NAVAID on the

IAP. Pilots must exercise extreme caution to preclude either a

dangerously early or late descent on final. Do not confuse GPS

distance with DME.

Verify APR ARM is annunciated within 30 NM of the airfield.

Select the SuperNav 5 display. Set the scale to AUTO.

NOTE

The CDI scale will smoothly change from + 5.0 NM to + 1.0 NM

full deflection at this time. The CDI scale is in NM not degrees.

Select LEG mode prior to the IAF.

At IAF perform 6 Ts.

Once established on the arc:

Twist in the desired track from the GPS into the CDI.

The Active WPT will now be the point at the end of the arc. This is where the GPS

needle will be pointing.

Configure to BAC 4 NM prior to FAWP.

NOTE

If the aircraft is on the arc, the CDI will be centered. The GPS

needle will point to the next WPT not the NAVAID. Use the CDI

to stay on the arc. The desired track will be located in the bottom

left corner of the GPS in SuperNav 5.

10. Once on the FAC, ensure the Active WPT is the FAWP.

NOTE

The KLN 900 display should indicate a solid line through the

FAWP oriented accurately to display the FAC and the aircraft's

position relative to it.

GLOBAL POSITIONING SYSTEM

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