Does the AI needs active lock to fire?

[Trueknight (OP)]

In my first combat with Aurora I'm having a lot of troubles from a couple of precursor ship...I got hit by missiles without no trace of the enemy (I know about them because of a recon mission I did before engaging).
I tought that all ships (human or AI) needed active lock before firing but in this case there's no trace of active sensors, and I've quite decent EM sensors on my ships, so I really can't understand. The only logical explanation I've is that AI is using passive sensor to lock fire...

[GreatTuna]

Yes, they need to maintain active sensor lock to fire.

About EM detection, what do you consider "quite decent"? It's usually not easy to detect EM radiation from sensors.
IIRC active sensors emit radiation equal to their strength, meaning that Precursor ship with, for example, 280 str sensor, will be detected with 140 str EM detector in range of 39.2 millions of kilometers.

Again, I may be wrong on that.

[Trueknight (OP)]

If that's the case my EM sensors are not decent at all...

[GreatTuna]

If that's the case my EM sensors are not decent at all...

In that case I'd advice you to invest in thermal sensors instead. They really shine against spoilers especially Invaders, who don't even try to hide their 4000|8000 thermal signatures.
My thermals are usually picking up enemy's engines even before an active sensor picks up enemy ship.

[Haji]

As precursor ships are somewhat randomized, this may not be always true, but my survey ship with EM sensor strength 66 managed to detect their active sensor (with range over 200m kilometers) before entering it. At a guess I'd say that EM strength 50 or lower will not allow you to detect their active sensors before entering their range, so if you have lower than that (say, 30) it's entirely possible to be hit by missiles from unknown source.

[Trueknight (OP)]

I've made it!! I had to rely on thermals, as suggested...that was how I found about the enemy in the first place, so I probably had to go that way from the start.

Anyway, I sent my screening units ahead, moving VERY slowly until I spotted their engines...luckily they were sitting idle, but with engines powered up... if they were on the move I'd would have been though to intercept them as they're faster then anything I've...

I've then sent my main force ahead VERY VERY slow, until I got into missile range. The whole thing took me almost 10 days in-game (and half a night out-game ) but now it's my turn to give them a surprise 

[Trueknight (OP)]

Thanks for the help by the way...this discussion made me wonder...what's the point of having EM passive sensors?
If I understand it correctly, sensors too small are totally useless as they can't detect active emissions before the ships that mounts it is detected by the enemy.
 
I was operating under the assumption that things in Aurora worked like in the real naval warfare, where any passive sensors (ESM for example) had much more range than any active sensor; by definition a passive should detect emissions before those get back to the active emitter, so any passive sensor should at least detect other ship when it enters range... of course since this is Sci-Fi I could think about a lot of possible techno-babble explanations for this not being true anymore.

Anyway, do you use EM passive in your ships at low tech level? What do you think about them?

[GreatTuna]

Anyway, do you use EM passive in your ships at low tech level? What do you think about them?

I put both EM and thermal sensors on my ships: size 1 on commercial ships\main combatants, size 10 on survey ships.
At low TL they're not very useful (in fact, active sensors aren't useful too for detection purposes due to very short range), but get progressively better with better tech.

...this discussion made me wonder...what's the point of having EM passive sensors?

They also detect shield emissions. However, no one ever is using shields, save for players and Swarm queens and matriarchs.
Improving EM sensitivity improves active sensors as well, and they provide some intel data (enemy sensor resolution\range).

[alex_brunius]

I was operating under the assumption that things in Aurora worked like in the real naval warfare, where any passive sensors (ESM for example) had much more range than any active sensor; by definition a passive should detect emissions before those get back to the active emitter, so any passive sensor should at least detect other ship when it enters range...

Is it really true that a crude WW2 radar warning device would be able to detect a modern naval radar with different wavelengths and many many times higher sensitivity??



A radar warning device with same technology/sensitivity per size should logically only need to detect half as strong signal ( since they detect it where it bounce back ).

And a passive device could be made half as big as an Active if we assume 50% of the active device is sender and 50% is reciever.


So using the above logic you should be able to detect the active sensor passivly at 2x range with an active sensor of your own. Or if you have a dedicated passive device of same size at 4x range using same tech level.

I don't know if that is the way Aurora works though.

[Haji]

Thanks for the help by the way...this discussion made me wonder...what's the point of having EM passive sensors?
If I understand it correctly, sensors too small are totally useless as they can't detect active emissions before the ships that mounts it is detected by the enemy.

As far as I can tell, the EM sensors generally detect ships at longer ranges but only those that emit EM signature, which means they have active shields or (more often) active sensors on. Thermal sensors have shorter detection ranges but they can detect any ship. In addition, as was pointed out by GreatTuna, EM sensor sensitivity also improves active sensors, so researching them kills two birds with one stone. As such players usually have higher EM detection tech than thermal detection tech.

In case of one of the spoilers I have detected thermal signature of one of it's ships at about 1/3 - 1/2 (I wasn't actually paying attention to that, so I can't give the exact figures) the distance at which I detected it's active sensors. My ship had EM and thermal sensor of the same exact sensitivity. Also, in the example I have given earlier a three hundred tonnes EM sensors with sensitivity tech 11 (Ion Engines era basically) allowed me to detect active sensors from a much more advanced warship before I entered the range of said active sensor. So they are useful, assuming they are of adequate size.

[Jorgen_CAB]

This is really, really simple math...

If you have EM sensitivity of say 8 and Active Scanner strength 16, just for the sake of experimentation.

If you have a size 5 resolution 1 active sensor it has a reach of 6.4m km for GPS of 5*16*1=80
If you have a size 5 resolution 5 active sensor it has a reach of 14.3m km for GPS of 5*16*5=400
If you have a size 5 resolution 20 active sensor it has a reach of 28.6m km for GPS of 5*16*20=1600
If you have a size 5 resolution 60 active sensor it has a reach of 49.6m km for GPS of 5*16*60=4800
If you have a size 5 resolution 120 active sensor it has a reach of 70.1m km for GPS of 5*16*120=9600

If you have a size 5 EM (40m km for 1000 EM GPS) sensor you pick up the above sensors at...

Res 1 - 3.2m km (6.4m)
Res 5 - 16m km (14.3m)
Res 20 - 64m km (28.6m)
Res 60 - 192m km (49.6m)
Res 120 - 384m km (70.1m)

The breaking point for a same size EM is about resolution 5 for a size five EM, smaller resolution will need a larger EM than active scanner in this particular case.

In the case above you can use roughly a 0.5 size EM to detect a resolution 120 at the same distance. It really don't matter if you make the active scanner twice as big because it just radiate twice the energy. So a 0.5 passive EM is enough to detect it at the same distance.

So, if you put a size 5 EM passive and lets say a size five resolution 120 you are going to detect all but any active at resolution 5 and higher before they detect you. And you may detect any ship at 6000t or more at a distance of 70m km.

You "only" need an EM size ten to detect resolution 1 sensors before they detect you.

Dedicated reconnaissance ships should perhaps mount a size 15 EM to be sure to detect any active at large enough distance.

But in order to detect medium to large resolution scanners you can use very small EM passive sensors.

A few things to note is that a 250t fighter can never mount a big enough EM sensor to know they have been actively scanned by an enemy ship, they need to rely on some early warning type of ship using very sensitive EM to pick up such scanners. Otherwise your fighters might run into a nasty surprise.

Also... be wary of ground based tracking stations. Let's say you are close to a military outpost protected by some FAC and a missile base and they have a level 3 ground based tracking station with a basic strength of say 300. They now have a strength of 900. They will detect a size 5 resolution 5 sensor at a distance of 360m km and a size 5 resolution 120 at 8.6b km. If your ship emit say 500 thermal (10.000t ship traveling at 2500km/s) it is detected at 450m km.

[linkxsc]

Just a stupid random thought. Can planetary sensors be used as the active sensor in combat. Like i doubt it in this game right now, but why not? Or why not a ground based active sensor complex?

[Jorgen_CAB]

You need an active sensor. What you can do is to build a PDC and place a large active sensor in it. But in general it is better with a huge passive complex and a smaller fast scout with a much smaller and cheaper active sensor.

Large active sensors are insanely expensive, both to build but even worse to research.

Remember that as soon as you turn on a decently sized sensor with even a modest resolution you have already lost initiative. You want to detect an enemy using passive sensors so you can be the aggressor not the other way around.

[Person012345]

You need an active sensor. What you can do is to build a PDC and place a large active sensor in it. But in general it is better with a huge passive complex and a smaller fast scout with a much smaller and cheaper active sensor.

Large active sensors are insanely expensive, both to build but even worse to research.

Remember that as soon as you turn on a decently sized sensor with even a modest resolution you have already lost initiative. You want to detect an enemy using passive sensors so you can be the aggressor not the other way around.

There are benefits to having a PDC based sensor though, for example being harder to damage and destroy. And a decent sized colony is going to shine like a beacon anyway.

[Jorgen_CAB]

As long as I don't have to research a specific very large active sensor I would perhaps build a command bunker with an active in it as a backup sensor. I would then have one or more scouts with active sensors as well. Small scouts with active sensors are pretty hard to engage in combat so they don't require much defences.

There is nothing wrong with building a larger active sensor and stick it into a PDC as long as you can afford to invest in the RP needed to design them.

If you also have a small military outpost with no real population it might not actually radiate that much EM or Thermal, then some additional stealth can be useful.