Hello!

I'm trying to follow the JustFlight 737 Professional tutorial provided in the manual but am having persistent problems getting the autopilot to intercept the ILS for runway 9R at KORD.

Everything goes smoothly until the bottom of page 106 of the manual, when on a heading of 040 to intercept the ILS, the course deviation indicatior starts to center (so I know the correct frequency is set on NAV1, plus the DME checks out) so I set the autopilot mode to VOR LOC to start tracking the ILS to 9R, and the plane starts turning away from the runway to a heading of 360!

I have the NAV/GPS mode selector in the NAV position, so am really stumped at this behaviour!

Has anyone else had a similar experience, or could there be something I don't have set correctly for the plane just to start heading north!?

Thanks for your time,

Harry

Your interception angle is some high 50 degrees. You should lower that to no more than 30 degrees but I doubt that will resolve the issue of the plane turning the opposite direction.

Thanks for the reply Olli, I guess it is an unnecessarily sharp turn, highlighted by the speed in which the course deviation indicator come accross the HSI(!), however it is what is stated in the tutorial.

I'm wondering if there is some connection I'm not making between NAV1, my desired course and the autopilot... North seems an intriguingly 'default' course!

Seems like you're waiting too long to arm NAV/LOC on the autopilot; you don't need to wait until the needle is alive.  Use a heading of 060 and arm the autopilot as soon as the 060 heading is established.

What airspeed?

Thank you Tube and Rag, I will try that, however I still would have thought the autopilot would make some effort to steer the plane towards the localiser, even if I had overshot my desired radial before engaging it.

 

Ryan, I'm aiming for 154 knots at this point of the approach...

 

The thing that gets me is that its not like the plane does nothing, but makes a very definite turn to a seemingly arbitrary heading!

I may be very wrong here, but when I did something similar in the PMDG tutorial #1, it said to set both NAV1 AND NAV2, to the ILS frequency..

Does yours say that at all?

Hi Richard,

 

Nope, it just states to set the NAV1 frequency to 111.10 and set the course selector to 090.

 

I did however, try an approach on 14R instead, and everything worked as expected.

 

I think I've solved it now, the manual states 110.10 for 09R, however looking here...

 

http://www.fltplan.com/airportinformation/ord.htm

 

110.10 is the frequency for 04R, guess it must be a typo, which is obviously fantastic for people who are a bit green and following a tutorial!