reported INS OFF behavior

[SexyTomato]

The INS keeps working even I set the knob to OFF. The alignment just keeps working.

If I set it to ATT and then back to NORM, then to OFF and back to NORM, the normal alignment does not seem to work. As you can see in the track, the true heading completely froze up.

Viper INS doesn't stop working with knob in OFF.trk

[Lord Vader]

Hello @SexyTomato

I don't know what you're trying to achieve by doing what you're doing in this track. You stop and restart the alignment procedure various times, moving the aircraft between attempts and not inputting and confirming new coordinates when you do so. I can't imagine why would a pilot do this. Of course the system will fail.

Please follow the correct procedures for alignment contained in our DCS: F-16C manual page 163.

[SexyTomato]

Hello @Lord Vader

11 minutes ago, Lord Vader said:

Hello @SexyTomato

I don't know what you're trying to achieve by doing what you're doing in this track. You stop and restart the alignment procedure various times, moving the aircraft between attempts and not inputting and confirming new coordinates when you do so. I can't imagine why would a pilot do this. Of course the system will fail.

Please follow the correct procedures for alignment contained in our DCS: F-16C manual page 163.

Well just test things out in case I would like to restart normal alignment.

First, the INS shouldn't be working when I set it to off, that's the bottom line.

Second, in Normal alignment, the INS should begin to attain true heading and attitude information from 98-90 according to the manual page 164. It doesn't do so when I turn it off and on again, that's what I am trying to say.

[SexyTomato]

Not sure why you are ignoring this obvious bug, so I am gonna further explain it.

As you can see in the track, after I turn the INS knob to OFF and wait for 10 seconds according to the manual, the INS is still working apparently. On the INS page, the LAT/LONG coordinate, altitude, true heading, and ground speed still change, the pitch ladder in the HUD still has relative movement relative to the aircraft movement. And in the previous track, the INS doesn't stop aligning as you can see the pitch ladder still moves after I switch it to OFF, indicating that it still tries to find the attitude.

Viper INS doesn't stop working with knob in OFF.trk

[Lord Vader]

@SexyTomato

This is a different item you're presenting now. Above you were inducing several errors on the alignment, expecting the system to proceed as if you didn't. 
Now you're presenting an apparent issue with navigation continuing to update data if INS (even GPS, I tested) is deliberately turned off.

We designed this system to be operated according to procedures. And those procedures tells us that if you lose INS data or it becomes degraded mid flight, with or especially without GPS, you would need to perform an IFA. You're not supposed to fly with no data unless you get a complete system loss. 

Currently in DCS, if the pilot (for whatever reason) wishes to completely turn off INS (and GPS) he does get some level of data loss, you'll lose weapon guidance (CCRP, PRE) and the FPV, for example. I will present this situation internally to see if we can degrade the data any further. 

[SexyTomato]

@Lord Vader

18 hours ago, Lord Vader said:

This is a different item you're presenting now.

On 1/31/2025 at 12:21 AM, SexyTomato said:

The INS keeps working even I set the knob to OFF. The alignment just keeps working.

This is the first item I presented but whatever, I am not gonna argue about it.

18 hours ago, Lord Vader said:

Above you were inducing several errors on the alignment, expecting the system to proceed as if you didn't.

Yeah this is the second item. Normally, if you do a normal alignment on the ground, the INS will do the true heading and attitude alignment from 98-90. But if you turn it off and do the normal alignment again (I think it is legit when I am on the ground and not moving), the INS wouldn't do the true heading and attitude alignment again. Because when you do it the first time, you will notice the pitch ladder on the HUD moves as the INS tries to do the attitude alignment. When I turn it off and NORM again, the pitch ladder doesn't move anymore. I don't know if this behavior is simulated intentionally or not and currently in DCS the true heading continues to be updated even I turn it OFF. So in order to prove it, I did the trick to get the true heading stuck (which I think it is another bug?). Then when I did the realignment again, you will notice the INS doesn't do its job to align the true heading. However as you judged that it got stuck because I broke the system and the true heading may keep working in degraded navigation mode, I guess only your team can clarify it.

[Lord Vader]

I meant this was not what you demonstrated in your first track. Again, please follow procedures regarding aligning INS correctly. We can't be focused on incorrect procedures as you did in your track, hence my replies. 

We're just evaluating what to do when INS is off. 

Thanks for your patience.