Flight director in TACAN and ILS working properly?

[vvince]

Hello,

I have been trying several times TACAN / ILS approaches, and it seems that the flight director on the ADI is not reliable...

TACAN navigation:
TACAN is selected with the navigation mode selector knob, a valid TACAN signal is tracked, the course is set, and the heading marker is set to coincide with the course arrow : the bank steering bar does not properly guide to intercept the selected radial (as set on the course selector). See the first picture bellow : way off course, bank steering bar centered.

ILS approach :
ILS is selected with the navigation mode selector knob, ILS is ON and a chanel with valid ILS frequency is selected, the heading marker is set to coincide with the course arrow : see pictures 2 and 3 (3 shows the PAPI lights at the same time than picture 2) : the pitch steering bar (centered) does not guide properly, it is not consistant with the glide slope as displayed y the Vertical Displacement Pointer of the ADI, and also not with the PAPI lights. And the bank steering bar does also guide a bit off the runway...
The situation of pictures 2 and 3 results from an approach done by following the ADI steering bars in ILS mode from about 10-15nm.

This was done between EDON (take off) toward EDDT (Berlin Tegel, landing) with TCN of 70X, ILS 110.1MHz, and a course of 259 degrees.

Any idea? Am I doing something wrong?

Thanks, cheers
Vvince

[JonathanBleeker]

Ouch....Will see what I can come up with. I can't promise a soon fix though due to a heavy workload at the moment.