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Posted by: Charlie Beeler
« on: September 12, 2013, 01:50:25 PM »

Missile guidence was re-written in '09. 

If a target is lost/destroyed missiles with onboard sensors will continue to the last know target location unless a new target is detected.  All control by the launching MFC ends with the loss of the orginal target.

Relevent discussion(s) are circa June 2009.
Posted by: Erik L
« on: September 05, 2013, 08:13:18 AM »

Quote from: Paul M on September 05, 2013, 03:46:31 AM
Eric...this is really something for Steve.

My take on it is (if it is correct I haven't a clue):

Ship 1 is targeting fighter A.  Missiles launched from the group including Ship 1 destroy fighter A, but some missiles Ship 1 fired remain.  Fire Control on Ship 1 is now without a target.  Missiles remaining at the end of the turn will use onboard sensors to switch to the nearby fighter B as they can see it.

Next turn Ship 1 targets fighter C and launches new missiles.  Those missiles target fighter C, the other missiles target fighter B as they are self guiding at this point.

I would assume that once the seeker head on the missile activates to control the missile the fire control of the launching ship is no longer relevant.  While it could go either way it does sort of defeat the purpose of putting sensors in the missile (baring the fact that without them they would self destruct) and it means that it doesn't matter what level of sensors you put in so long as the launching ship acquires a new target the missiles acquire it.  But that is all...best guesses and may have no resemblance to the code.



Like I said, the post where Steve mentions ship board targetting trumping missile targetting is 5 years old, so from an earlier version. My read on what he said is as long as the ship has a viable fire control, it has control. Obviously, without looking at the code or Steve saying, all we have is guesswork.
Posted by: Paul M
« on: September 05, 2013, 03:46:31 AM »

Eric...this is really something for Steve.

My take on it is (if it is correct I haven't a clue):

Ship 1 is targeting fighter A.  Missiles launched from the group including Ship 1 destroy fighter A, but some missiles Ship 1 fired remain.  Fire Control on Ship 1 is now without a target.  Missiles remaining at the end of the turn will use onboard sensors to switch to the nearby fighter B as they can see it.

Next turn Ship 1 targets fighter C and launches new missiles.  Those missiles target fighter C, the other missiles target fighter B as they are self guiding at this point.

I would assume that once the seeker head on the missile activates to control the missile the fire control of the launching ship is no longer relevant.  While it could go either way it does sort of defeat the purpose of putting sensors in the missile (baring the fact that without them they would self destruct) and it means that it doesn't matter what level of sensors you put in so long as the launching ship acquires a new target the missiles acquire it.  But that is all...best guesses and may have no resemblance to the code.

Posted by: Erik L
« on: September 04, 2013, 02:01:35 PM »

Quote from: wobbly on September 04, 2013, 01:40:10 PM
Is there a way to get the game to dump a detailed log of combat? If so is it readable?

You can export the event log. That is about as much detail as you'll get I believe.
Posted by: wobbly
« on: September 04, 2013, 01:40:10 PM »

Is there a way to get the game to dump a detailed log of combat? If so is it readable?
Posted by: Erik L
« on: September 04, 2013, 01:36:34 PM »

Quote from: Paul M on September 04, 2013, 01:22:27 PM
From the list you give sensor update is made at the end of the turn.  So the missiles acquire the new target at that point. 
I agree. However, read the caveat. If the ship that fired the missile still has an active fire control, any missiles left over will target the new target. Ship FC override missile sensors for targetting.

So missile sensors come into play in the following situations:
1. Firing ship destroyed/FC destroyed.
2. Firing ship can no longer see any targets and hence target anything.
3. Firing ship does not target anything, regardless of being able to or not.

So in the situation where you have 2 ships next to each other, and one is destroyed; any missiles that targetted that ship will NOT target anything until the firing ship does if it can.

That does leave a murky area that we would need a definitive answer from Steve on. Situation 3 should allow the on-board sensors to guide the missile. I can see it going either way.
Posted by: Paul M
« on: September 04, 2013, 01:22:27 PM »

From the list you give sensor update is made at the end of the turn.  So the missiles acquire the new target at that point.  It is up to Steve at this point to say how it works because I have to admit I would assume* this is how it has to be inorder for the onboard missile sensors to have any worth what so ever.

*Assume:==means "To make an ASS out of yoU and ME."
Posted by: Erik L
« on: September 04, 2013, 10:29:57 AM »

Quote from: Paul M on September 04, 2013, 12:23:24 AM
Erik the end of the turn x or the start of the turn x+1 are the same point in time so it doesn't matter when it happens.  If in turn x there are targets in detection range due to the primary target being destroyed, the missile acquiring the target at the end of the turn or the start of the turn x+1 has the same result.  The missile enages.  For a missiles orbiting and waiting to pick up the next target it should again not matter as the target basically has to end the turn in the detection radius for the seeker head to kick in.

It all depends on when movement takes place versus sensor checks. If we have the following order: Move, Sensor. Then if a ship is destroyed post-Sensor, they can very easily move out of range prior to the next check.
Per http://aurora2.pentarch.org/index.php/topic,532.0.html this is the Movement phase:
 
Quote
- Fleets Move
- Fighter Groups Move
- Fighter Groups Reload (remaining rearm time is reduced)
- Monsters Move (including precursors)
- Missile Salvos move (including intercept, point blank point defence and damage allocation\planetary bombardment)
- Life pod Endurance Check (any lifepods that have exhausted their endurance are removed)
- Sensor Update (all sensors are checked for new contacts)
So my read on this is Ship moves, Missile moves and hits, ship blows up, missiles look for new targets. So in theory, a missile with sensors will target a new ship. With one caveat.
Quote from: Steve Walmsley on June 03, 2008, 11:16:02 AM

The missiles will target whatever the fire control linked to their launchers is targeted upon. Once a target is destroyed, the missiles will hold position waiting for a new target to be selected.

Missiles with onboard sensors will use them to select a target if they are not currently under shipboard control

Steve
This is from a very old post (June 2008) and I couldn't find any newer posts that contradicted this.
Posted by: Paul M
« on: September 04, 2013, 09:49:32 AM »

Before this get too far off track...  the utlity of a sensor on an AAM is going to be very situationally dependent.  The one case Alex mentions is the primary time it would have value and there are other cases it might come into play but the real reason to put a sensor in an AAM is for when the AAM is used in anti-fighter or anti-ship mode.

And for this is more likely then not a better idea to use active sensors.

But from my point of view what I am trying to point out is that it isn't completely daft (at higher tech levels) and that things I would ordinarily have not thought possible have happened so..."never say never" sort of thing.
Posted by: alex_brunius
« on: September 04, 2013, 07:45:31 AM »

Quote from: Hawkeye on September 03, 2013, 01:50:13 PM
Conclusion:
No matter what I tried, the active sensor missile always performed better than the thermal sensor one. The only exception would be an ASM, that is used vs. a target, smaller than the sensor-resolution. Then the thermal is better.
Vs. missiles, sensors, at least at my tech level, are absolutely, totaly useless.

Are you sure about being useless against missiles? If the enemy firing missiles is stationary ( for example a PDC or a hostile ship with knocked out engines ) this should mean that the next missile salvo always moves exactly in the same spots (assuming you are travelling directly towards or away from it).

In theory this would give your AMMs with minimal sensors a 100% chance to re-target, correct?
Posted by: Paul M
« on: September 04, 2013, 12:23:24 AM »

Erik the end of the turn x or the start of the turn x+1 are the same point in time so it doesn't matter when it happens.  If in turn x there are targets in detection range due to the primary target being destroyed, the missile acquiring the target at the end of the turn or the start of the turn x+1 has the same result.  The missile enages.  For a missiles orbiting and waiting to pick up the next target it should again not matter as the target basically has to end the turn in the detection radius for the seeker head to kick in.

Ralf...you have just proven the adage "there are lies, damn lies and statistics."  Clearly "bigger is better" in terms of detection radius but while I'd not touch what the chance of detection is with a 10' pole for missiles for ships or fighters it is solely a question of target spread vrs detection radius.  So unless your fighter squadron has a seperation between fighters of greater than 16K km for the IR or 60K km for the active seeker then they will be engaged.

If you like active or passive is probably equally a matter of taste but also of what your enemies are like, I don't think there is a universal answer.

If at the end of the day it is sensible to do it for AAMs is a function of tech level, and frankly I would only think about doing it once my tech level is very high.  For missiles intended for AF or AS work it makes sense since it is likely that there will be other ships/fighters close enough to be easily detected near a target that is destroyed.
Posted by: Hawkeye
« on: September 03, 2013, 01:50:13 PM »

Ok, I did throw together a few missiles with thermal and active sensors.

My techs are:
   Magneto Plasma Drive
   Max. Engine Power Modifier    x2
   Warhead Strength per MSP   5
   Active Grav Sensor Strength:    21
   EM Sensor Sensitivity:       11
   Thermal Sensor Sensitivity:    11

First an ASM-6. Both variants dedicate 0.6 MSP to sensors/reactor

Quote
Missile Size: 6 MSP  (0.3 HS)     Warhead: 5    Armour: 0     Manoeuvre Rating: 10
Speed: 31200 km/s    Engine Endurance: 33 minutes   Range: 62.3m km
Active Sensor Strength: 0.3706   Sensitivity Modifier: 110%
Resolution: 100    Maximum Range vs 5000 ton object (or larger): 400,000 km
Cost Per Missile: 4.1829
Chance to Hit: 1k km/s 312%   3k km/s 100%   5k km/s 62.4%   10k km/s 31.2%

Quote
Missile Size: 6 MSP  (0.3 HS)     Warhead: 5    Armour: 0     Manoeuvre Rating: 10
Speed: 31200 km/s    Engine Endurance: 33 minutes   Range: 62.3m km
Thermal Sensor Strength: 0.2414    Detect Sig Strength 1000:  241,400 km
Cost Per Missile: 3.9763
Chance to Hit: 1k km/s 312%   3k km/s 100%   5k km/s 62.4%   10k km/s 31.2%

A hostile ship of 5000+ tons would have to have a thermal sig of more than 1657, to be spottet at greater range from the thermal sensor ASM than the active sensor ASM.
Of course, the thermal gets better, the smaller the enemy ship gets, as the thermal sig (and thus the range it can be spotted) decreases linearly, while the range of the active is reduces by the square.


Now an anti-figher missile:

Quote
Missile Size: 3.999 MSP  (0.19995 HS)     Warhead: 4    Armour: 0     Manoeuvre Rating: 13
Speed: 40000 km/s    Engine Endurance: 12 minutes   Range: 29.2m km
Active Sensor Strength: 0.2468   Sensitivity Modifier: 110%
Resolution: 5    Maximum Range vs 250 ton object (or larger): 60,000 km
Cost Per Missile: 3.6504
Chance to Hit: 1k km/s 520%   3k km/s 169%   5k km/s 104%   10k km/s 52%

Quote
Missile Size: 4 MSP  (0.2 HS)     Warhead: 4    Armour: 0     Manoeuvre Rating: 13
Speed: 40000 km/s    Engine Endurance: 12 minutes   Range: 29.2m km
Thermal Sensor Strength: 0.1612    Detect Sig Strength 1000:  161,200 km
Cost Per Missile: 3.5135
Chance to Hit: 1k km/s 520%   3k km/s 169%   5k km/s 104%   10k km/s 52%

My current scout-fighter design moves at 13,800 km/s, but I could probably get a smaller figher-bomber to move at up to 15,000 km/s, so lets run with those numbers. At that speed, it moves 75,000 km per 5-sec tic, giving my active sensor missile a 80% chance, the fighter will be in range after a 5-second tic.
That fighter has a thermal sig of 96, which means, the thermal sensor AFM will pick it up at a range of 15,475 km, which translates to a 20.6% chance to be picked up after a 5-second tic.


Finally an AMM

Quote
Missile Size: 1 MSP  (0.05 HS)     Warhead: 1    Armour: 0     Manoeuvre Rating: 11
Speed: 38400 km/s    Engine Endurance: 2 minutes   Range: 4.4m km
Active Sensor Strength: 0.105   Sensitivity Modifier: 110%
Resolution: 1    Maximum Range vs 50 ton object (or larger): 10,000 km
Cost Per Missile: 0.9236
Chance to Hit: 1k km/s 422.4%   3k km/s 132%   5k km/s 84.5%   10k km/s 42.2%

Quote
Missile Size: 0.999 MSP  (0.04995 HS)     Warhead: 1    Armour: 0     Manoeuvre Rating: 11
Speed: 38400 km/s    Engine Endurance: 2 minutes   Range: 4.4m km
Thermal Sensor Strength: 0.0682    Detect Sig Strength 1000:  68,200 km
Cost Per Missile: 0.8643
Chance to Hit: 1k km/s 422.4%   3k km/s 132%   5k km/s 84.5%   10k km/s 42.2%

1) Putting the space the sensor takes into agility doubles the to-hit chance.
2) A size-6 ASM, moving at 32000 km/s I threw together has a thermal sig of 9.6 and will move 160,000 km per 5-second tic.

a) The active sensor AMM will pick up a size-6 or smaller missile at a range of 1089km, giving it a  0.68% chance to notice an enemy missile after a 5-second tic

b) The thermal sensor AMM will pick up that missile at a range of 654km, which gives it a chance of 0.41% to pick up a new ASM after a 5-second tic.

Conclusion:
No matter what I tried, the active sensor missile always performed better than the thermal sensor one. The only exception would be an ASM, that is used vs. a target, smaller than the sensor-resolution. Then the thermal is better.
Vs. missiles, sensors, at least at my tech level, are absolutely, totaly useless.










Posted by: Erik L
« on: September 03, 2013, 10:18:21 AM »

If a missile (AMM or ASM) targets a ship at location A, and by the time they are near, the ship is destroyed; then missiles without on-board sensors destruct. Missiles with on-board sensors will only react to anything in their radius. Since sensor checks are made (I don't recall which) either at the start of the increment, or the end; the new potential target needs to be in that radius to be considered. If it is just outside the radius, and moves completely through the radius during the increment, it is not eligble for targetting. If the missiles do not find anything, they will "circle" until they find an eligible target.

The reason a lot of people consider missile sensors impractical, is that the radius on them is so small most things can cross it without being "detected".
Posted by: Paul M
« on: September 03, 2013, 09:17:43 AM »

Quote from: Erik Luken on September 03, 2013, 08:49:26 AM
Just remember, if the missile sensor has a radius of say 25km, the potential target needs to be in that radius at the boundaries of the time increment. If it crosses the entire radius during the increment, it won't be targetted.

This is true but the fact your missiles made contact and there is another missile group reload seconds behind that means that it is likely that the missiles will (if flying recipricol courses) actually end up right on top of each other or within engagement range if the sensor has a fairly reasonable range.  The question is more if the course is recipricol enough for this to happen.

While it is a long shot and will be exceptionally hit and miss in practice the alternative is your AAM self destructing so in this case any chance of it happening is an infinite improvement over no chance at all.

But again this is something that makes no sense in the case of low tech level missiles but might be a worthwhile option at higher tech levels....especially since in this case you might have a detection radius against a missile drive in the thousands of km for a relatively modest investment in seaker hardware.

Added In Edit:  Or I missunderstand the situation about what the missiles will do without a target as mine have always self destructed (the counter missiles).  I am assuming they continue to fly the course they were on but if they do something else then the utility of the seaker head would likely be less.  It would then be only of interest for the times when you use your counter missiles against fighters...and here I would think it would be worth while.
Posted by: Erik L
« on: September 03, 2013, 08:49:26 AM »

Just remember, if the missile sensor has a radius of say 25km, the potential target needs to be in that radius at the boundaries of the time increment. If it crosses the entire radius during the increment, it won't be targetted.