CDI Failure (VOR, TAC)

JOINT ADVANCED MULTI-ENGINE T-44A

visually check your radial/DME on the approach plate or enroute chart. If required, make a timed turn

to the reciprocal, rotate the course set knob until the CDI centers with a TO indication, and fly direct to

the station maintaining course using the RMI needles in conjunction with the CDI. At station passage,

make a timed turn to the desired intercept heading, rotate the course set knob to the FAC and track the

outbound course using heading information supplied by the co-pilot. Accomplish the course reversal

using timed turns. When the CDI starts to center commence another 15 second timed turn to final.

Two methods used to track inbound/outbound are:

Method 1. Check the tail of the needle to determine present radial. Visualize the radial, and DME if

available, to determine your position on the approach plate. Turn in the direction required for course

intercept. Make timed turns to maintain the FAC.

Method 2. Set the CDI and heading bug to present a graphic display of FAC and present heading.

Ask the CP for heading calls (off the wet compass) and set the bug on the corresponding

heading.

Utilize the CDI set to the FAC (radial to intercept).

You now have a cockpit presentation of your heading, final approach course (radial to

intercept), and required direction to turn (intercept angle) to return to course.

Configure the aircraft at the normal point and continue the approach using NH procedures.

3. ILS/LOC No Heading Approach. An ILS or LOC approach is possible with no heading information

either by utilizing radar vectors to final or by executing a procedure turn if the IAP contains a LOM

(locator outer marker; an NDB aligned on course centerline). If radar vectors are not available, proceed

direct to the LOM using NDB no heading techniques. At station passage, make a timed turn to the desired

intercept heading, rotate the course set knob to the FAC and track the localizer course outbound using

heading information supplied by the co-pilot and techniques discussed above for CDI tracking. NDB

information (NH) will also be available and can be used throughout the procedure turn to maintain SA and

accomplish the course reversal using NDB NH techniques. In either case, when the localizer "becomes

alive" and starts to move off full deflection, commence a timed turn to final. Once established inbound on

the localizer and at the proper altitude, track the localizer and glideslope as in a normal ILS or LOC

approach using guidance from the needles/CDI. Configure the aircraft as previously discussed.

F. CDI Failure (VOR, TAC).

If the CDI fails, or is found to be out of tolerance during an instrument check, the following procedures

are available:

VOR. A VOR approach can be flown using the needles on the RMI. Use the "RMI only" techniques

described in section 404 and used on all normal NDB approaches. Remember, the needle will always

point to the station, the head of the needle will always "fall" and the tail of the needle will always

"rise".

TACAN. TACAN approaches can be flown using just the bearing pointer and "tail" on the HSI. The

"RMI only" techniques above will be applied using the HSI. Under these circumstances, the following

techniques may be helpful:

Inbound Course Intercept. A common technique to use when intercepting a course inbound is to put

the heading bug on the inbound course; the pointer will "fall" to the heading bug when on an intercept

heading. The intercept is completed by turning to put the pointer under the upper lubber line.

Maintain course by keeping the pointer centered on the heading bug.

Outbound Course Intercept. When intercepting a course outbound, the heading bug is put on the

outbound course; this time, the "tail" will "rise" to the heading bug when on an intercept heading.

Turning to put the heading bug and the "tail" under the upper lubber line completes the intercept.

Maintain course by keeping the "tail" centered on the heading bug.

G. Visual Approach.

Visual approaches reduce pilot/controller workload and expedite traffic by shortening flight paths to

the airport. A visual approach is conducted on an IFR flight plan and authorizes the pilot to proceed

RADIO INSTRUMENTS STAGE

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