Navigation problem.... Help

[friviere]

hi,

I worked on a program witch needed to use the autopilot of flight simulator 2004. But i got some troubles and i hope that someone can help me...

First the heading order : I send an heading order throught the offsets

07C8 (Autopilot heading lock)

07CC (Autopilot heading value, as degrees*65536/360) and the plane displayed the good heading on FCU but the trueHeding (and magHeading) have some degree of difference. The track seems to be more realistic. So do the the heading autopilot is a track autopilot or do i miss something ?

The altitude order : When i wnt to managed aircraft in altitude, i use offsets

07D0 (Autopilot altitude lock)

07D4 (Autopilot altitude value, as metres*65536)

and the plane never goes to the altitude order but just stay at current altitude. Do i something wrong ?

Thanks for helping me....

[Pete Dowson]

I send an heading order throught the offsets

07C8 (Autopilot heading lock)

07CC (Autopilot heading value, as degrees*65536/360) and the plane displayed the good heading on FCU but the trueHeding (and magHeading) have some degree of difference. The track seems to be more realistic. So do the the heading autopilot is a track autopilot or do i miss something ?

No, the autopilot maintains heading if heading hold is engaged. The heading shown (and set) is magnetic, not true.

Don't forget that the autopilot must also be engaged. Setting a heading hold without autopilot is valid, but only gives you flight director guidance, not control.

Generally you would set heading hold then change the heading value -- this is simply because of the way FS works.

The altitude order : When i wnt to managed aircraft in altitude, i use offsets

07D0 (Autopilot altitude lock)

07D4 (Autopilot altitude value, as metres*65536)

and the plane never goes to the altitude order but just stay at current altitude. Do i something wrong ?

Just set the hold then adjust the altitude. The autopilot must be engaged or, again, it is only a flight direction facility.

Test with a default FS aircraft. You talk about the FCU, but none of the defaults have an FCU (the Boeings have MCPs of a sort). Many add-on aircraft panels do not use the FS autopilot facilities so you may be wasting your time writing to these places.

Regards,

Pete

[friviere]

Thank you for answering...

But you said "hold" and not lock... is there a difference ? What's the difference between alt lock and alt hold (07D0 and 07D8)?

Regards...

[Pete Dowson]

... you said "hold" and not lock... is there a difference ? What's the difference between alt lock and alt hold (07D0 and 07D8)?

There's only one altitude hold. Lock is just another word for it, used inside FS -- MCPs/FCUs are generally marked "hold".

You are misreading the other. Offset 07D8 is ATTITUDE hold, not ALTITUDE -- there's quite a difference! Unfortunately I have never known FS's attitude hold to work.

Regards,

Pete

[gr8guitar]

Hello, can someone tell my the flight director (FD) in most aircraft doesn't match the ILS indicator on an approach in manual mode? Is there a setting I'm missing? The FD should give the same direction command as the ILS if radios are set, etc. I have the course (nav set at 110.30, OBS set to 112° - KGJT-rwy 11), and APR selected but I have never been able to trust most of the FD's (whether single or dual cue) command in manual on an ILS approach. The FD's work properly with FeelThere's Embraer 135/145 and and an old 737/727 FD as shown in the picture provided. I saved the picture as an jpg to save size of file.

[gr8guitar]

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