Although I'm not sure, in MAN mode, I can only get ALT HOLD to work. I think it's supposed to be like that in MAN mode. I sometimes have to turn the AP on and off a few times while trying to get TACAN or HDG HOLD to work.

This seems to do the trick for me. Set the Mode Selector knob to TACAN, then set heading bug to your desired heading, then turn the Heading Hold switch on. AFTER doing all that, turn the AP servo switch ON.

And don't forget to turn the Flight Director switch ON (it's behind the Pilots yoke). Failing to turn it on will definitely prevent the AP from working. I have made that mistake a few times. Usually after being away from the B-52 for a while. It has me scratching my head trying to think of what I might have done wrong to prevent the AP from working.

Mark

I don't think I have ever tried to use the Heading Hold while in NOR mode. I'll have to give that a try.

Mark

MustanGrande wrote on Mar 7^th, 2011 at 10:47pm:

I've done a test flight. And the results are as follows.

When the AP is ON and the Nav Mode Selector Switch is TACAN, VOR, ILS and ILS APP and Heading Selector Switch is in MAN, it overrides the NAV mode and so the AP is actually in HEADING HOLD mode and follows the Heading Bug. The Nav Modes work correctly, if the Heading Selector Switch is in NOR mode, the Nav Mode selected is controlling the direction of the flight.

If the Flight Director Switch is OFF, the AP Nav Mode and Heading Hold do not work. Altitude Hold does work with the FD switch OFF.

So after doing all those tests, the AP works as the Manual states it should. Your problem is simply because the Flight Director switch is OFF.

Mark