Area Navigation (RNAV)

JOINT ADVANCED MULTI-ENGINE T-44A

The point with the greater range is established at the outer edge of the compass card. The point with

the lesser range is visualized at a place proportional to the distance represented by the outer edge of the

compass card.

Determine Heading. Determine a precise heading from the aircraft position to the desired point.

Determine the heading to the point by connecting the aircraft position to desired point with an

imaginary line. Establish another line in the same direction, parallel to the original line through the

center of the compass card. This will establish a no-wind heading to the desired point.

Adjust Heading. Adjust aircraft heading as necessary and proceed to the point.

Drift. Apply any known wind drift correction. The effect of wind drift and any inaccuracy of the

initial solution may be compensated for by repeating the previous steps while enroute.

Distance. The distance to the desired point can be estimated since the distance between the aircraft

position and the desired point is proportionate to the distance established from the center to outer edge

of the compass card.

Update. Update heading enroute to refine your solution and correct for winds.

NOTE: The same problem can be easily and accurately solved on the CPU/26A computer (preflight planning, etc.).

This is done on the wind face by imagining the center grommet is the station and applying the same basic techniques

as above.

I. Area Navigation (RNAV). Pilots are encouraged to utilize RNAV on cross country flights when

feasible. This will result in more direct routing and reduced fuel consumption. The majority of VT-31

aircraft have now been modified with FMS/GPS, thus rendering RNAV somewhat obsolete (when the GPS

is working). If you do not have GPS or it is not operational, RNAV is a good substitute for providing direct

routing off airways.

RNAV Usage. Many fleet aircraft utilize self-contained RNAV equipment (inertial nav). The T-44

requires reception of an external signal (radial and DME) to provide course information. The following

points may help in utilizing the system:

Consult the Enroute Supplement to determine the elevation for each VOR or TACAN which will

be utilized to define a waypoint. Remember field elevation is often different from NAVAID

elevation. Example: San Antonio International elevation 809'; VORTAC elevation 1160'. Round

elevation to the nearest hundred. For instance 1160 would equal 12. Pencil the elevation on your

chart (next to the NAVAID) for future reference.

Prepare a "mileage ruler." Place a jetlog card next to the mileage scale of the appropriate high/low

chart; tick off and label mileage. This will be a handy reference both before and during flight.

Pack a straightedge for use in flight.

Utilize charted crossing radials/airways or defined fixes (if possible) to plan the waypoints you

intend to use for navigation. If a charted radial is not available, utilize a cardinal radial from the

NAVAID compass rose and extend it to cross your course. Pencil a small circle over each

waypoint. Use the "mileage ruler" to gauge distance if DME is not charted. Acceptable radial

input is 000.0 to 359.9 degrees. Acceptable DME input is 000.0 to 249.9 NM.

RNAV Waypoint Usage (VOR). VOR RNAV is preferred over TACAN RNAV because it is easier to use.

Enter VOR frequency in the desired waypoint. Type in an extra zero on the frequency. This lets the "box"

know that you intend to enter an RNAV waypoint and not just a standard VOR frequency. Enter NAVAID

elevation (215 ft would be 02). Enter radial, including tenths (090 would be 090.0). Enter distance,

including tenths (23 DME would be 23.0). If any mistakes are made, press "Clr" and enter the correct input.

Press "Pre" (preset). This will save the waypoint. When ready, D-U-D the stored RNAV waypoint.

Radial/DME information from the NAVAID must be receivable to utilize RNAV. Check "Linear Deviation"

and "RNAV" illuminated. The DME Indicator Panel will display mileage to the VOR. Groundspeed

displayed on the DME Indicator Panel is accurate only when transiting directly to or away from the

NAVAID.

RADIO INSTRUMENTS STAGE

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