Figure 6 - P-8010013

INSTRUMENT NAVIGATION

Figure 6

The curvature of the earth will sometimes be a limiting factor in VOR reception, especially

at lower altitudes (See Figure 6 above). Reception range increases with aircraft altitude and is

about 40nm at 1,000' AGL. VOR facilities are spaced about 90 miles apart to ensure adequate

navigational coverage over an airway.

4. In the T-34, VOR bearing information is displayed on the #1 needle of the RMI. The

displayed information has an accuracy of +1.

5. VOR identification signal. All VORs transmit an audio signal which allows the aircrew

to positively determine if the VOR station to which they are tuned is actually the one desired.

The signal may be Morse code, corresponding to the 3 - letter identifier of the station; it may

be a recorded voice which in plain English states the name of the facility; or it may be a

combination of both. The receiver in the aircraft is capable of voice reception. The recorded

message described above is one type of voice message it can receive. If necessary, however,

many VOR stations are capable of sending actual voice transmissions. A VOR equipped

aircraft will not normally receive voice transmission over its VOR equipment; however, in the

event of two-way radio failure it does possess that capability. The aircraft has the capability to

receive voice communications only. VOR stations which are not capable of making voice

transmissions have their frequency underlined on the enroute charts.

TACTICAL AIR NAVIGATION (TACAN):

TACAN is quite similar to VOR; however, it represents an improvement over the VOR and

provides the aircrew with improved accuracy and a means of determining distance from the

selected station. It will be your primary means of instrument navigation here at VT-10.

RADIO AIDS TO NAVIGATION 1-7