The true/mag BRAA and Bullseye problem

[Robin_Hood]

So the subject has already been touched a couple times, here and here, but I thought I'd bring it back once more, now that we're talking about F/A-18C roadmap and everything.

 

First, there is a strange discrepancy in the F/A-18C, where Bullseye location of contacts in the radar and SA page is always in true bearings, but for BRAA, the radar always shows true while the SA page shows true or magnetic depending on setting in HSI DATA.

 

And secondly, there is still the question of which they should use.

 

So two questions that I hope can be answered :

 

1°) Is it normal that the SA page BRAA depends on the DATA setting, but the bullseye doesn't?

2°) Shouldn't everything use magnetic anyway ? Or is it selectable (for both, for SA page only?)

 

I always heard the USAF and USN use magnetic reference for both BRAA and Bullseye, how can the F/A-18C not be capable of displaying that?

 

Of course, this also raises the question of the AI AWACS, that do give true bearings, which may be the reason behind all this. I'm guessing they could be made to give magnetic bearings, but it would hinder FC3 users. Although right now it hinders everyone else, so...

 

Just for the record, although I don't think it really necessary, here's a track that shows the problem. At 42 seconds, HSI in mag, then true.

TrueMag.trk

[hein22]

Our hornet IRL has both radar and SA formats showing whatever is set in DATA-A/C subpages of HSI format. The reason why in the radar is not the case is simply a forced bug that ED must have done to be able to live with awacs calls. Obviously it would have been much better to simulate it correctly and let the pilot set true in hsi so he or she can correlate with awacs calls. Afaik though, that bearing setting in hsi never worked correctly so maybe that's another reason why the radar is wrong.