Su27 vertical&horizontal scan - Help needed

[apocom]

I think the pressure isn't set when u enter your aircraft. That's where the discrepancy comes from...Might be wrong though... I'dont have much experience with this.

 

That doesn't explain why my targets altitude is displayed correctly, I think it's a bug, because it makes zero sense.

 

So basically u are getting the same values as I am..hmhmhm..So if the radar is 6,3°-3,7° it should look like this:

 

I've run again some test and changed my distance to the targets just to see how they (dis)appear from my radar.

I'm not exactly sure if that are the correct values, because we have so many potential errors ingame (radar refresh rate, small errors in altitude and distance) that I think that is the best approximation we can get. I'm not even sure if the radar covers exactly 10° and not something like 10.05°. But with the ingame constraints I think we can't do any better.

 

So, if I should bet some money, I would say +6.3° and -3.7° is how the radar is orientated.

[holimoli]

Have you checked your flight with tacview? That's where my problems occurs. I have no idea what more correct is, tacview or the ingame display.

 

The aircrafts are set to

 

-3.7° | -3.8° | -3.9° | +/-0° | +6.4° | +6.3° | +6.2° | +6.1°

 

According to tacview my overall error is 3m.

 

As you can see -3.8° ,-3.9° and +6.4° are missing.

 

First of all, I have no idea if I've done everything correct. Mostly because the values ingame differ. I belive tacview is right, just because if I put my plane at 5000m ASL, tacview tells me it's 5000m ASL but ingame its 4890m.

 

 

Second, these values seems strange at first sight, but they have their own beauty. For every 10km your radar looks 1km up (more like 1.1) and for every 15km your radar looks 1km down.

 

That doesn't explain why my targets altitude is displayed correctly, I think it's a bug, because it makes zero sense.

 

I see, yeah that makes no sense.:/

 

I've run again some test and changed my distance to the targets just to see how they (dis)appear from my radar.

I'm not exactly sure if that are the correct values, because we have so many potential errors ingame (radar refresh rate, small errors in altitude and distance) that I think that is the best approximation we can get. I'm not even sure if the radar covers exactly 10° and not something like 10.05°. But with the ingame constraints I think we can't do any better.

 

So, if I should bet some money, I would say +6.3° and -3.7° is how the radar is orientated.

 

yep..still I'm gonna do some more tests to be precise as possible. Honestly the best would be if some of the mods could kindly ask one of the devs about the radar. :) :):music_whistling:

 

Thanks though for your help and effort!

[apocom]

Ok, I've run some again some test today, just because the topic bothered me. The question is, how would you position the radar in the aircraft if you were the engineer.

 

1. Using some integer wouldn't help the pilot. It's not that he will start doing some sin/cos calculations during the flight (and integer doesn't help here at all).

2. The way that elevation works in this aircraft doesn't make any sense if you are using degree for the radar orientation.

 

So I would implement the radar with at least -3.814°. This way at 15km the radar scans 1km below your level.

 

I've run again multiple tests, and at 15km I can resolve a target that is 1km below.

 

Why is this interesting?

The SU27 is missing a feature (and some more) the F15 has. At the F15 you see your radar cone at a specified distance. With this information you can now easily calculate your needed elevation.

 

For example you are flying at 6000m and you want to be able to scan ground level 60km ahead of you. Just set the expected target range to 60km, at this distance you know, your radar is scanning down to 2km. So just move the radar 2km down and you are at ground level. The maximum altitude you are scanning now is 10km[6 (your altitude) + 6 (60km) - 2 (radar change)]. You can do this calculation easily while flying.

 

Again I have no idea if I've done everything correctly, I tried to be as precise as possible. Would be glad if someone can confirm or refute.

[Frostie]

Probably best to save complication wind the values in to a more usable figure eg. 1000m and 500m.

But go with what you feel comfortable with.

 

So at 6000m altitude you could use

eg. at 10km your radar sees +1000m -500m

so at 60km you see +6000 -3000

set -2 elevation would give +4000 -5000 ( this may actually see to the ground level but as a solution to workout quick easy math it works, plus setting elevation -3 won't hurt as you get more coverage on the ground)

Edited November 13, 2015 by Frostie

[apocom]

Probably best to save complication wind the values in to a more usable figure eg. 1000m and 500m.

But go with what you feel comfortable with.

 

So at 6000m altitude you could use

eg. at 10km your radar sees +1000m -500m

so at 60km you see +6000 -3000

set -2 elevation would give +4000 -1000 ( this may actually see to the ground level but as a solution to workout quick easy math it works, plus setting elevation -3 won't hurt as you get more coverage on the ground)

 

At 10km your radar sees +1000m -666m at least (overall the radar covers 1763m, and it looks like they used the additional ~100m for the upward scan area).

So at 60km you see +6000 and -4000, set -2 elevation at 60km gives you now +4000 and -6000.

[holimoli]

Ok, I've run some again some test today, just because the topic bothered me. The question is, how would you position the radar in the aircraft if you were the engineer.

 

1. Using some integer wouldn't help the pilot. It's not that he will start doing some sin/cos calculations during the flight (and integer doesn't help here at all).

2. The way that elevation works in this aircraft doesn't make any sense if you are using degree for the radar orientation.

 

So I would implement the radar with at least -3.814°. This way at 15km the radar scans 1km below your level.

 

 

 

I thought about the same...like: What does the pilot use as reference for manipulating the radar and why is it like 6,3 up and 3,8 down.

 

Anyway, I can't continue my tests atm since the ruler on F10 is bugged. Once that has been sorted I'll try to finish my tests :)

 

P.s.: Sry for the late reply

[Santi871]

Ok, I've run some again some test today, just because the topic bothered me. The question is, how would you position the radar in the aircraft if you were the engineer.

 

1. Using some integer wouldn't help the pilot. It's not that he will start doing some sin/cos calculations during the flight (and integer doesn't help here at all).

2. The way that elevation works in this aircraft doesn't make any sense if you are using degree for the radar orientation.

 

So I would implement the radar with at least -3.814°. This way at 15km the radar scans 1km below your level.

 

3 decimal accuracy is a little hard to achieve in real life :) Also, the Su27 and Mig29 were designed to work with GCI, that's why the "expected target range" setting is there - it makes it a lot easier if you were being guided by GCI.

[Frostie]

At 10km your radar sees +1000m -666m at least (overall the radar covers 1763m, and it looks like they used the additional ~100m for the upward scan area).

So at 60km you see +6000 and -4000, set -2 elevation at 60km gives you now +4000 and -6000.

Yes I meant to say -2 @60km gives you +4000 and -5000(edited my original post). This figure is using the calculations rounded up or down to 100, not accurate but close enough and much easier to calculate on the fly.

That is why i'm using the basis of @10km +1000 -500, making simple math.

Edited November 13, 2015 by Frostie

[Ragnarok]

My old pattern of scan scheduling. Calculation of negative tangent. Someone may be helpful.