At some point prior to your completion of the Instrument Checklist, your instructor will direct
you to take avionics command. This will be necessary for you to complete the final items on the
checklist. When you take avionics command, first ensure the UHF is set to the same channel your
instructor had previously selected, then check the transponder is in STBY with the correct code
The NAVAID test will be the same as that in Contact Stage with one addition. Since you will be
using the IND350 on your RI flights, it is necessary to check this instrument. Accomplish this as
follows: while depressing the SYS TEST button, twist the OBS to the same course indicated by
the head of the VOR needle. Select VOR on the VOR/TACAN switch. The CDI should center
and the TOFROM indicator should indicate TO. Repeat the procedure for the TACAN. While
conducting the system test the DME should indicate 0.0 or 0.1. Bring any difficulty in
completing the checklist to your instructor's attention at once.
The above NAVAID test is accomplished using internal selftest
circuitry. In addition, test your NAVAIDS prior to flight using
ground checkpoints or VOR Test facilities (VOT) if available.
Ground checkpoints: Airfields normally provide specific ground points to check
VOR/TACAN accuracy. Azimuth must be within +4º of the designated radial and DME within ½
mile or 3% of the distance to the station, whichever is greater.
Certified airborne checkpoints have been established on airways and near VOR stations to
check the accuracy of VOR azimuth in flight. VOR airborne checkpoints are published in FLIP
Area Planning (AP1) under country listing.
"CRESTVIEW, FL (Bob Sikes) 106, 8.6 NM; over rot bcn; 1200 feet."
For the example above, flying directly over the rotating beacon at Bob Sikes airport with
Crestview VORTAC tuned, the VOR needle and IND350 should indicate a radial of 106 with
8.6 in the DME.
With an error in excess of "4° during a ground check or 6° during
an airborne check", IFR flight should not be attempted.
VOR test facility (VOT): Some airfields are equipped with a VOT. The VOT transmits a
test signal identified by a continuous series of dots or a continuous 1020 hertz tone. With the
IND350 should center the CDI with a "TO" indication. Some VOTs are available to the user
while airborne, others are limited to ground use only. VOT frequencies are listed in the IFR
Enroute Supplement opposite "Radio Aids to Navigation."
RADIO INSTRUMENT FLIGHT PROCEDURES 6-3