IRST targeting range?

Unread postPosted: 26 Apr 2018, 02:32
by armedupdate
Are there targeting range to IRSTs? Lets say it spots a target head on at 50 km. Using triangulation can it target at those distances?

I remember the targeting range against a stationary target in the Chinese EOTS version to be 50 km despite it can see out to 100 km.

One thing that seems to concern me is that even if the target is spotted and ID'd using IFF, is the amount of vapor in the atmosphere is going to throw the actual coordinate way off due to refraction. IR missiles have this problem as well however they can correct it when they are approaching the target.

Re: IRST targeting range?

Unread postPosted: 26 Apr 2018, 03:05
by SpudmanWP
An IRST can determine rage in one of several ways.

1. Single-Ship triangulation: In a head-on scenario this is more problematic than a side shot.

2. Multi-Ship triangulation: Mutch faster and more accurate than #1 and no real limit to range. More an issue of ID'ing the target rather than range.

3. Laser range-finder: Quick and accurate but range limited. Public Russian numbers have a number of 20km for the laser.

4. Shape ID: If the target plane can be ID'd then the range can be estimated based on the length of the shape.

Re: IRST targeting range?

Unread postPosted: 26 Apr 2018, 03:17
by armedupdate
SpudmanWP wrote:An IRST can determine rage in one of several ways.

1. Single-Ship triangulation: In a head-on scenario this is more problematic than a side shot.

2. Multi-Ship triangulation: Mutch faster and more accurate than #1 and no real limit to range. More an issue of ID'ing the target rather than range.

3. Laser range-finder: Quick and accurate but range limited. Public Russian numbers have a number of 20km for the laser.

4. Shape ID: If the target plane can be ID'd then the range can be estimated based on the length of the shape.

Multi-ship triangulation is the best way practically. LRFs are limited by range, shape ID is too iffy due to pixels count being inaccurate, and single ship is not good against moving targets.

Re: IRST targeting range?

Unread postPosted: 26 Apr 2018, 11:26
by hornetfinn
SpudmanWP wrote:3. Laser range-finder: Quick and accurate but range limited. Public Russian numbers have a number of 20km for the laser.


High-powered diode-pumped lasers can have higher range than that, something like 50 km is possible depending on target features. Naturally target reflectivity and atmospheric visibility affect the range a lot.

Interesting datasheet about L3 diode-pumped laser performance:
http://www2.l3t.com/alst/pdfs/datasheets/DP_ELRF-V.pdf

Re: IRST targeting range?

Unread postPosted: 26 Apr 2018, 16:53
by SpudmanWP
US systems don't advertise range so I was limited to stating the range of Russian systems.

Re: IRST targeting range?

Unread postPosted: 26 Apr 2018, 22:41
by armedupdate
Does Russian figures 20 km mean with triangulation or just LRF?

Re: IRST targeting range?

Unread postPosted: 27 Apr 2018, 13:38
by sprstdlyscottsmn
That is the LRF range of a single OLS system.