Alignment - Stored versus Complete

[Whozdär]

Hello all! 

 

I had originally posted in a bug report thread after being linked to it but it's more a general question than a bug report, so I'm just reposting it here. Hope that's ok. 

A few updates ago, I noticed that complete alignements in the viper no longer reached value 6 in precision and both stored and complete would just reach 10 and sit there.

Is there no longer any precision gain or any reason (other than immersion / realism) for players to use complete alignments in the game? Possible to get a statement on that?

I got from BigNewy through discord that "a full alignment to 10 will be more precise than a stored alignment", and I wonder if we can have any details on that, what is the advantage currently implemented in the game?

 

 

And the original chatter on discord, for full context:

 

 

Thank you!

 

 

Edited November 16, 2021 by Whozdär

[Frederf]

Status 10 normal alignments are better than status 10 stored alignments in some regards. The status number does not tell you all there is to know about the alignment quality. There are different aspects of alignment quality that can't be boiled into a single number. You might have just as good heading discovery but bad translational velocities at the same status number for instance. It's just a multiplier against a particular standard expectation. "10" means "1.0" or 100% the standard drift expectation. Status 20 is 2.0x or twice as much drift expected relative to standard. I doubt you'd notice the difference much in the real airplane (especially GPS coupled) and probably zero difference in DCS. You can try it, turn off the GPS switch and fly around for an hour and see if the steerpoint diamond drifts relative to a landmark over that time. Without GPS filtering it should and the lesser alignments should drift more.

Honestly I don't think any INS alignment quality is modeled at all. It's a complicated thing to model when the airplane is working perfectly and much more sophisticated to model the imperfections like INS drift. I think status 60 is the highest status in the normal operational range and this could be tested. Take away GPS coupling and fly around with a status 55 alignment and just see if it drifts. Status 10 is supposed to be within approximately 0.8nm per hour so 20, 30, 40, 50, 60 are 1.6, 2.4, 3.2, 4.0, 5.6nm (approx, could be less, could be more) per hour respectively. That should give a feeling or how long you have to test to see a detectable drift.

EDIT: Did the test. 90 minute flight normal alignment status 61 no GPS waypoint displaced 4.3nm drift but I forgot to enter L/L at align (HSI had a degraded flag). Did the test a second time entering L/L same 61 status and drift was about 1.7nm for 30 minutes flight. Both work out to the same rate and less than the dire predictions of the manual. Did a test with status 60 stored alignment and drift was 0.4nm over 30min better than normal which is weird. But it could be random so many trails and an average is best.

The biggest difference is that stored alignments need to be prepared beforehand. A prepared alignment or "cocked jet" is prepared to go very quickly for intercept or base defense missions for example. The whole squadron wouldn't be prepared this way just 2 or so airplanes to have a quick reaction force. You can't tow them around or do maintenance or anything that would move them. An AA mission like an intercept doesn't care about alignment quality so much like an AG mission. Any realistic AG mission would always align as best as possible before takeoff as time is not a factor and precision is key. You're spending 20-30 minutes (or more) typically on the ground in a real F-16 mission. The alignment time is NBD.

Status <10 is reserved for EIA alignment which are special normal alignments that involve reorienting the airplane in the middle of the process. When the airplane detects an EIA it will continue to count down from "1.0" down to at best 0.6 or status 6. DCS doesn't yet model EIA recognition so status 10 is the best possible. I think hot ramp still show status 6 but it's not something a player can achieve.

Edited November 16, 2021 by Frederf

[Machalot]

15 hours ago, Frederf said:

But it could be random so many trails and an average is best.

Should be randomly distributed within the stated accuracy and zero mean. It would be interesting to see if DCS produces random or deterministic nav error. 

[Whozdär]

Thank you @Frederf for an extensive answer.

 

So the bottom line seems to be that there's no gain from doing a complete alignment in the game as long as you wait to reach value 10 on the alignment.

Even less point to care if GPS is on. 

[Carbon715]

In addition to, indication 10 on stored finishes entirely too fast compared to the real thing

Edited November 17, 2021 by Carbon715