New Tutorial:: F-15C Radar Intro and LRS

[RedTiger]

what do numbers 1,2,3,4 in "1 MED", "2 HI", "3 MED", "4 HI" mean ?

 

as i've known, MED and HI are medium and high pulses repetition frequency

 

MY guess: the numbers refer to the bar scan and the "MED"/"HIGH" refer to the PRF, like you said.

 

The bar scan setting controls how many times the radar sweeps the sky. With 4 its going back and forth in four lines across the sky, one on top of each other:

 

1 >>>>>>>>>>>>>>>>>>>

 

<<<<<<<<<<<<<<<<<<<2

 

3 >>>>>>>>>>>>>>>>>>>

 

<<<<<<<<<<<<<<<<<<<4

 

 

In the real thing (at least with the AN/APG-68, don't see any reason why the Eagle would be any different) you can lower the amount for a quicker scan but at cost of not sweeping as much of the sky. In LOMAC, its stuck on 4 and cannot be changed.

 

The PRF, if we're right, is the same idea as the PRF settings in the Flanker.

Edited August 23, 2008 by RedTiger

[GGTharos]

The F-15C automatically interleaves PRF since it doesn't have to worry much about performance; another little known fact is that part of the ECCM means using a different frequency on each bar scan.

[RvEYoda]

 

Do you mean the elevation scale on the left? Or is there something else I'm not seeing? In some respects it doesn't matter that there isn't one, though the radar's elevation position can be a bit nebulous when the TDC is positioned at ranges less than 25 nm.

 

There are two situations where it is a matter of life and death I would say.

 

1. When you get information like "bandit at -15 degrees", in the Viper

you slew a little blue rotated "T" to the -15 position, rather than

calculate target altitude. In the 15 it is the "<" marker (not working like this in LoFC though, read on)

 

2. You see a bandit between 10-20 nm but at a difficult angle

so you cant use bore sight lock (or Long range bore like real 15).

here normally in a 15 or 16 you would simply read his position on your

pitch ladder and then slew the "<" to the appropriate angle. I will explain

the "<" function a little later.

 

The indicator in the f-16 is a rotated T, and the same thing looks like a "<" in the 15 radar. The graphics are there

in LoFC, but the behaviour is incorrect. It should step (like it does)

4 separate bars (or 1 or 2 if you select that, functionality not in LO).

 

Each line in the scale not only represents 10 angels(or was it 5?) for

the circle indicators, but also represent each 5 or 10 degrees for

the "<".

 

Each radar bar sweep covers approx 2.3-2.5 degrees pitch, and the 4

bars in total make up for a little less than a +-5 degree sweep in pitch.

 

However the lockon "<" moves +- 20 degrees around horizon,

regardless of radar elevation. What it should show is

approx +-5 in a total of 4 2.3-2.5 bars(sweeps. This way you

move the "<" to whatever elevation in degrees you want.

 

This functionality is implemented for russian radar systems in LoFC

but they put in the "step" movement for the 15 "<" just for show, its not

doing what it should ;)

Edited August 23, 2008 by =RvE=Yoda

[RedTiger]

The F-15C automatically interleaves PRF since it doesn't have to worry much about performance; another little known fact is that part of the ECCM means using a different frequency on each bar scan.

 

I meant that it works the same as the Flanker in LOMAC land. :P ;)

[Ironhand]

...You...slew the "<" to the appropriate angle...

Ahhh. So, if I'm understanding you correctly, the antenna elevation carat ("<") should not be bouncing up and down with each bar sweep (as it does in the sim) but simply sit at the elevation angle you have selected?

 

Rich

[RvEYoda]

Ahhh. So, if I'm understanding you correctly, the antenna elevation carat ("<") should not be bouncing up and down with each bar sweep (as it does in the sim) but simply sit at the elevation angle you have selected?

 

Rich

 

No it should bounce - But not like it does right now.

It should bounce in about 2.3 degree steps 1 per sweep(=per "bar"),

and the bounce positions are related to your elevation around horizon

in degrees.

 

Right now it bounces like 10-20 degrees per sweep and positions dont change

regardless of elevation, so its just there for show.

 

I'll make a vid of the f-16 radar. it's very similar.

 

when using smaller azimuth settings, the sweep zone

should also be directly related to cursor position

(azimuth wise). This means you dont need to have a

separate control for moving azimuth left right.

 

there are a few other details as well......but we

could go on all day on whats missing in lockon.

 

Suffice to say F-15 radar is a very simple machine to

handle compared to lockon's variant, because so much

is missing in the lo variant you have many more things

to worry about that are automatic in the real thing.

Edited August 24, 2008 by =RvE=Yoda

[walternowi]

I remember playing Falcon 4, the radar can be adjusted to do 4-bar, 2-bar or 1-bar sweep. Is this a feature that is also available for the F-15C?

[GGTharos]

The F-15C can do 8-bar full azimuth scans if it wants to. Just not in LO.

[RvEYoda]

8 bar....wow

thats almost +- 10 degrees - ME WANTS!

[GGTharos]

... Actually it depends on the distance; the radar scans bars at 1 deg intervals at 40nm, IIRC, 2.5 at 20.

My guess is you can do some funky things with the sidelobes closer in and cover more space.

[RvEYoda]

hmm, interesting.

variable sized bars, i have not heard of this before, at least not for the 16.

This is not implemented in any falcon4 version.

 

Is this feature eagle specific?

 

What controls it, VSD scale setting?

[Ironhand]

No it should bounce - But not like it does right now.

It should bounce in about 2.3 degree steps 1 per sweep(=per "bar"),

and the bounce positions are related to your elevation around horizon

in degrees... I'll make a vid of the f-16 radar. it's very similar.

I think I understand what you're saying but I'd like to see the vid, if you have the chance to make one.

 

when using smaller azimuth settings, the sweep zone

should also be directly related to cursor position

(azimuth wise). This means you dont need to have a

separate control for moving azimuth left right.

That would make life much easier. :)

 

Suffice to say F-15 radar is a very simple machine to

handle compared to lockon's variant, because so much

is missing in the lo variant you have many more things

to worry about that are automatic in the real thing.

I just wonder which variant of the APG-63 they were trying to model at the time they started coding. But I suppose, since production ended in 1986, it ought to be the last one. Hell, the early models didn't even have a bona fide TWS mode.

 

 

 

The F-15C can do 8-bar full azimuth scans if it wants to. Just not in LO.

This wouldn't be the AN/APG-63, though, would it? And that's a full azimuth scan? Not 15 degree?

 

Rich

Edited August 25, 2008 by Ironhand
Add GGTharos quote

[RvEYoda]

Ironhand i have recorded something in fraps.....but.......what format should I compress it with.

 

What do you usually use? I have not much experience with this :).

[Ironhand]

Ironhand i have recorded something in fraps.....but.......what format should I compress it with.

 

What do you usually use? I have not much experience with this :).

I normally use the XviD codec. DivX also compresses well but with slightly less quality. If it's a short video, use Huffy. The file size will be significantly larger than with either of those but the quality will remain excellent.

 

BTW, I like the Desktop image you posted in the other forum. :)

 

Rich

[RvEYoda]

;).

 

Huffy, not quite sure how to get that into vegas.

I will do xvid i think.

[Ironhand]

...I will do xvid i think.

XviD will do just fine. Thanks.

 

Vegas should know what codecs you have installed. If you don't see it listed, in all likelihood you don't have the codec installed.

 

Rich

[RvEYoda]

XviD will do just fine. Thanks.

 

Vegas should know what codecs you have installed. If you don't see it listed, in all likelihood you don't have the codec installed.

 

Rich

 

You have a PM

[RedTiger]

No it should bounce - But not like it does right now.

It should bounce in about 2.3 degree steps 1 per sweep(=per "bar"),

and the bounce positions are related to your elevation around horizon

in degrees.

 

Right now it bounces like 10-20 degrees per sweep and positions dont change

regardless of elevation, so its just there for show.

 

 

I just re-read this thread and I'm glad you mentioned this. After a stint in Falcon, when I came back to LOMAC I found it strange that the scan marker didn't visibly change its sweeps relative to your scan elevation. Its rather disconcerting looking.

[Ironhand]

You have a PM

As do you.

 

Rich