Scan Zone

[williehayesjr]

Help please. In the F15, whenever I try to lower my scan zone range, so that I can detect a far away target below me, the range automatically jumps to some high numbers. E.g., my scan zone is between 35 and 20 (35,000 AND 20,000 FT), I try to lower (RShift/.)it maybe to 10 to 20, it jumps back up to the 35 to 20 range; this happens each time I try to lower the scan elevation. The result is that, enemy fighters get much too close, because I could not detect them at their lower altitude.

[pr1malr8ge]

I bound my elevation scan control to my joy stick. But keep in mind that the altitude is based also on where your curser is. if its on the bottom of the scope you are going to have a very small range of altitude. If you want to widen the elevation you need the tdc up at the top. If you have the TDC up at the top this also allows you to more fine tune what altitudes you're looking at meaning you can use the elv control to look only low up to from 0 to 30+ then from say mid to High.

[Joni]

Just set the TDC on the upper side of the radar screen and then play with the scan zone up and down. That way you will see all your enemies. :)

[williehayesjr]

Scan Zone

 

Thanks guys. I figured it out. I had both the slider and a knob mapped to RShift/. or ;. One of them was turned all the way up preventing the other from operating properly.

 

Again, thanks a lot for your help.

[=4c=Nikola]

Just set the TDC on the upper side of the radar screen and then play with the scan zone up and down. That way you will see all your enemies. :)

 

That's not entirely true. In perfect scenario, he will see all contacts in an altitude range he set and at the range he set with TDC. Any contact that is closer than TDC position at radar screen and that is, in the same time, at the vertical border of the cone will be invisible.

 

The vertical range is computed as an cone-plane intersection, where position of the plane is determined by position of TDC. If a target aircraft is in different plane than TDC placed plane, the computed vertical range doesn't apply.

 

That's why it's important to set TDC at the range you expect your target and not at the upper side.

[Joni]

That is not correct. But in order not to start a discussion I will post a screenshot when I return home so the OP does not get confused.

 

Ill get home in a couple of hours.

 

I'm a naval aviator by the way ;)

[=4c=Nikola]

That's interesting, while we're waiting for your data which I'm interested to see, here is a little demonstration.

 

Aircraft is set at 18km (~10nm) ahead of me at ~19650ft (6000m).

 

 

First case, TDC is set at the distance of the target, and vertical range at 8-19. The target is invisible as it's above the cone.

 

 

Second case, TDC is set at the distance of the target, and vertical range at 9-20. The target is visible.

 

 

Now, third case, TDC is set at the upper side (~17.5nm), and vertical range is 2-20. Aircraft is inside projected range but it's invisible.

 

 

Fourth case, TDC is set at the upper side (~17.5nm), and vertical range is 11-29. Aircraft is still invisible.

 

 

Fifth case, TDC is set at the upper side (~17.5nm), and vertical range is 12-31. Finnaly, the aircraft is visible.

 

 

Now, I allow the possibility that I'm wrong, so I would like to read Piston85's interpretation, and how, I quote, "That way you will see all your enemies." adds up to this case?

Edited August 13, 2015 by =4c=Nikola

[Joni]

Im not going to get home till 5 more hours, but I do have this one that shows clearly how many contacts are shown closer to the TDC (much closer actually).

[Svend_Dellepude]

That's not entirely true. In perfect scenario, he will see all contacts in an altitude range he set and at the range he set with TDC. Any contact that is closer than TDC position at radar screen and that is, in the same time, at the vertical border of the cone will be invisible.

 

The vertical range is computed as an cone-plane intersection, where position of the plane is determined by position of TDC. If a target aircraft is in different plane than TDC placed plane, the computed vertical range doesn't apply.

 

That's why it's important to set TDC at the range you expect your target and not at the upper side.

 

In the SU-27 this is true, but in the F-15 it's not.

In the F-15 you have the full vertical sweep available all the time regardles of the position of the TDC.

[Frostie]

In the SU-27 this is true, but in the F-15 it's not.

In the F-15 you have the full vertical sweep available all the time regardles of the position of the TDC.

 

What Nikola says is that for example the TDC at 40nmi at an altitude of 1/0 depending on your own altitude you could be missing bandits at 10nmi who are flying low because the elevation doesn't give a reading below 0/0, there is no indication that you have more radar elevation available. The only way to realise this extra elevation is reduce the range the TDC is set at. Though saying the TDC controls the elevation is wrong.

Edited August 13, 2015 by Frostie

[=4c=Nikola]

Im not going to get home till 5 more hours, but I do have this one that shows clearly how many contacts are shown closer to the TDC (much closer actually).

 

That doesn't work in my DCS:

 

[Joni]

im thinking perhaps PRF setting? Was that target getting away?

[Exorcet]

Nikola is correct, unless I'm reading something incorrectly. The position of TDC has no effect on what the radar can see.

[Frostie]

Just set the TDC on the upper side of the radar screen and then play with the scan zone up and down. That way you will see all your enemies. :)

 

This is not fool proof. At altitude you will miss low and high bandits that are close unless you go out of bounds in the elevation readings.

[Joni]

Nikola is correct, unless I'm reading something incorrectly. The position of TDC has no effect on what the radar can see.

 

you mean Piston85 is correct? :music_whistling:

[=4c=Nikola]

im thinking perhaps PRF setting? Was that target getting away?

 

Yes, it's getting away. The same with any PRF.

[Joni]

Yes, it's getting away. The same with any PRF.

 

I think it has to be MED PRF for low closure target detection.

[=4c=Nikola]

In the SU-27 this is true, but in the F-15 it's not.

In the F-15 you have the full vertical sweep available all the time regardles of the position of the TDC.

 

That's impossible by the laws of physics.

 

For instance, if you fly at 6500ft, and set TDC at 5nm, the highest you can set vertical range is 22-27. What makes you think that if you set TDC at 160nm, you get 0-60 vertical range at 5nm?

 

I think it has to be MED PRF for low closure target detection.

 

That's true, and was the primary PRF for the test, but I tried with the other two just to make sure.

[Joni]

That's impossible by the laws of physics.

 

For instance, if you fly at 6500ft, and set TDC at 5nm, the highest you can set vertical range is 22-27. What makes you think that if you set TDC at 160nm, you get 0-60 vertical range at 5nm?

 

 

 

That's true, and was the primary PRF for the test, but I tried with the other two just to make sure.

 

 

Thats correct, and it is why when changing TDC positions the radar automatically changes the scan zone. But I guess my point is that radar coverage is set by scan zone and distance regardless of TDC position as long as it does not change the scan zone.

 

 

As for the test, I am not sure how well it is modeled in DCS since we are talking about a low fidelity module (or whatever it is called when it's not fully simulated) so we cant be sure.

[Exorcet]

you mean Piston85 is correct? :music_whistling:

I misunderstood your first post. Though I don't see why you would set the TDC to the top of the display. It won't give you additional coverage over setting it toward the bottom.

[Joni]

I misunderstood your first post. Though I don't see why you would set the TDC to the top of the display. It won't give you additional coverage over setting it toward the bottom.

 

Just to make the scan zone as bigger as possible

[=4c=Nikola]

Thats correct, and it is why when changing TDC positions the radar automatically changes the scan zone. But I guess my point is that radar coverage is set by scan zone and distance regardless of TDC position as long as it does not change the scan zone.

 

That's what I said. TDC doesn't affect scan zone itself, but computer calculates scan area at the distance set with TDC by pilot.

 

What you do by setting TDC to 160nm: You basically lose altitude range indication because it will read 0-60 and in that case your scan range for (for example) 20nm can be anywhere from 0-14 to 5-26 (if you're at 6500ft), which you don't know. If target is at 20nm at 0-5k ft or at 14-26k ft, you may see it or not, pure luck. If a the same target is above 26k you will not see it at all.

Edited August 13, 2015 by =4c=Nikola

[Joni]

thats right, but that was only an exagerated example, i dont set the radar that way.

 

we are on the same page then

[=4c=Nikola]

:thumbup:

[Svend_Dellepude]

That's impossible by the laws of physics.

 

For instance, if you fly at 6500ft, and set TDC at 5nm, the highest you can set vertical range is 22-27. What makes you think that if you set TDC at 160nm, you get 0-60 vertical range at 5nm?

sure.

 

C'mon man.

I never mentioned 0-60K feet, which i assume is what you mean.

I said you had the full vertical sweep range available, which means +/- 60° from your nose, regardless of the TDC. So if you point the radar 10° up with the TDC at 10nm and then move it to lets say 40nm, the radar is still pointed up 10°.

The cone of the radar is BTW also ~10° vertical.

Edited August 13, 2015 by Svend_Dellepude