Dudester22 Posted April 14, 2014 Share Posted April 14, 2014 I have just got used to most of the weapons now, but then I spotted something I might be doing wrong. I saw that some guy had made a check list on how to use a laser bomb, but the bit I don't understand is step seven on his list. I want to know why he turns on the lasers before selecting his target as SPI and then turns it off again? I thought the only time you needed to turn the laser on was after selecting a target as SPi and when the laser bomb was 8 to 12 seconds away from the target. 1) RMFCD select TGP > A/G OSB 2) RMFCD make SOI 3) China Hat Aft Long slave to SPI 4) Crosshair slew to target 5) TMS Fwd Short. Select AREA/POINT 6) DMS UP/DOWN zoom in/out 7) Laser on, create SPI (TMS Fwd Long), laser off Link to comment Share on other sites More sharing options...
kontiuka Posted April 14, 2014 Share Posted April 14, 2014 Well, step #7 is more important for JDAMs than LGBs. When you make a SPI without the laser, the TGP thinks you're SPIing the ground behind the target - as if the target isn't even there. When you make a SPI with the laser, the TGP makes the SPI right on the target. Without the laser, the SPI could be off just a few feet or several feet and could be the difference between a hit and a miss. Like I said, it's not that big a deal with LGBs because you'll be lasing them to the target anyways after release. But with other munitions it's more important. 1 Link to comment Share on other sites More sharing options...
Yurgon Posted April 14, 2014 Share Posted April 14, 2014 (edited) I want to know why he turns on the lasers before selecting his target as SPI and then turns it off again? I thought the only time you needed to turn the laser on was after selecting a target as SPi and when the laser bomb was 8 to 12 seconds away from the target. 1) RMFCD select TGP > A/G OSB 2) RMFCD make SOI 3) China Hat Aft Long slave to SPI 4) Crosshair slew to target 5) TMS Fwd Short. Select AREA/POINT 6) DMS UP/DOWN zoom in/out 7) Laser on, create SPI (TMS Fwd Long), laser off Step 3 should read "Slave TGP to Steerpoint", shouldn't it? Regarding the question, I only learned about the details of that a short while ago. Turning on the laser in step 7 of that list isn't usually necessary -- when setting the SPI to TGP with TMS Forward Long, it doesn't mean "Set this point as SPI". It actually means "The TGP will continually generate the SPI from now on, until SPI generator is moved to another sensor". Therefore, when the crosshairs are slewed on the TGP (with TGP as SPI generator), the SPI will move along with them. That of course means that it's not really important to get a perfectly accurate range by the time the SPI is set. It's more important to have an accurate range by the time of weapons deployment, which is usually a good bit later. Also, this whole accurate ranging business is most important when looking at the target from a shallow angle (while flying relatively low). LGBs are usually employed from high up, thus from a high angle, and the SPI should be spot-on unless the target is located in very steep terrain. One scenario where the exact range does play an important role is if you create markpoints on a target and then, at a later time, drop weapons on the markpoints rather than on a SPI (*), but that is a technique suited for JDAMs rather than LGBs. In essence, it shouldn't usually be necessary to use the laser as described in that list, but as long as the target isn't fitted with a laser warning system, it shouldn't hurt either. Ermm... and what kontiuka said. :) Edit: @Eddie: I hope I got it right this time :D Edit 2: Bad choice of words, I meant dropping on SPI, slaved to steerpoint. See here for clarification. Edited April 15, 2014 by Yurgon Clarification Link to comment Share on other sites More sharing options...
Dudester22 Posted April 14, 2014 Author Share Posted April 14, 2014 Thanks for the replies, but these answers bring me to another question. I read somewhere on these forums that you only need to use a TGP Spi for JADAM's and not use your laser. Why would a JADAM require a laser when it uses a GPS receiver and the inertial guidance system? Or are you saying it is just away to get the TGP on the exact mark before releasing the JADAM? I also didn't know you could drop JADAM's on markers instead of a SPI, so where in the manual does it explain this? Thanks! Link to comment Share on other sites More sharing options...
baltic_dragon Posted April 14, 2014 Share Posted April 14, 2014 The laser is used to determine exact range from the target, it is not used to guide the bomb to target afterwards. There was a very good video tutorial about it, I will post it once I get to work. Link to comment Share on other sites More sharing options...
Dudester22 Posted April 14, 2014 Author Share Posted April 14, 2014 (edited) The laser is used to determine exact range from the target, it is not used to guide the bomb to target afterwards. There was a very good video tutorial about it, I will post it once I get to work. Now I am confused. I read this article and nowhere here does it say it is to detect exact range. I will look at your video to see what you mean, but it doesn't mention range on that link I posted below. They also call it a Laser guided bomb, so the laser must play a part in guiding the bomb to the target. http://science.howstuffworks.com/smart-bomb1.htm Edited April 14, 2014 by Dudester22 Link to comment Share on other sites More sharing options...
kk0425 Posted April 14, 2014 Share Posted April 14, 2014 Dudester, maybe this will help explain why using a laser to set a markpoint (or SPI) is important for JDAMs. Link to comment Share on other sites More sharing options...
Kaiza Posted April 14, 2014 Share Posted April 14, 2014 (edited) Refer to Yurgons post, the others are not entirely correct.. Setting the SPI with the laser prior to the run in will not increase the accuracy of any LGB dropped from a high pass. Even setting it for JDAMs is pointless, because as Yurgons has said the SPI will continuously update, so as soon as you turn the laser off, your SPI will update and you have lost your so called "extra accuracy". The key is to remember: when you are setting a SPI, you are not setting a point on the ground, you are setting the point that your SOI is pointing at. If your SOI moves, so does your SPI. Your SPI is constantly updated. Step 7 is redundant so you can ignore it (unless you are making a mark point)? Once you have the TGP on the target you just need to keep the crosshairs there, line up in CCRP/CCIP, pickle the weapon and turn the laser on at around 8 secs to impact. Edited April 14, 2014 by Kaiza 1 [url=http://www.aef-hq.com.au/aef4/forumdisplay.php?262-Digital-Combat-Simulator][SIGPIC]http://img856.imageshack.us/img856/2500/a10161sqnsignitureedite.png[/SIGPIC][/url] Link to comment Share on other sites More sharing options...
Dudester22 Posted April 14, 2014 Author Share Posted April 14, 2014 Refer to Yurgons post, the others are not entirely correct.. Setting the SPI with the laser prior to the run in will not increase the accuracy of any LGB dropped from a high pass. Even setting it for JDAMs is pointless, because as Yurgons has said the SPI will continuously update, so as soon as you turn the laser off, your SPI will update and you have lost your so called "extra accuracy". The key is to remember: when you are setting a SPI, you are not setting a point on the ground, you are setting the point that your SOI is pointing at. If your SOI moves, so does your SPI. Your SPI is constantly updated. Step 7 is redundant so you can ignore it (unless you are making a mark point)? Once you have the TGP on the target you just need to keep the crosshairs there, line up in CCRP/CCIP, pickle the weapon and turn the laser on at around 8 secs to impact. Thanks for clearing it up this is what I have been doing all along. I just thought I was doing something wrong when I saw that checklist, but obviously I'm not because I mainly hit all of my targets doing it this way. Link to comment Share on other sites More sharing options...
baltic_dragon Posted April 14, 2014 Share Posted April 14, 2014 Dudester, maybe this will help explain why using a laser to set a markpoint (or SPI) is important for JDAMs. That is exactly the video I wanted to post. Link to comment Share on other sites More sharing options...
kontiuka Posted April 14, 2014 Share Posted April 14, 2014 I do believe the laser makes a difference because I had run a few tests a few months ago. I tried attacking the roof tops of tall buildings with JDAMs. When I made the TGP SPI with the laser off, the JDAM would miss by a hundred feet. With the laser on, it was right on target. If I recall correctly, I left the laser on until bomb release and then turned it off. Link to comment Share on other sites More sharing options...
kontiuka Posted April 14, 2014 Share Posted April 14, 2014 I also didn't know you could drop JADAM's on markers instead of a SPI, so where in the manual does it explain this? Thanks!I wasn't aware of this either. Unless you're talking about making a mark point a SPI. Link to comment Share on other sites More sharing options...
Flagrum Posted April 14, 2014 Share Posted April 14, 2014 I wasn't aware of this either. Unless you're talking about making a mark point a SPI. We can drop JDAMs only onto a SPI, but what that SPI is and where it came from is not relevant. Using markpoints for that usually only makes sense if you want to prepare several targets before running in. And the nice thing with markpoints is, that they are stored in the CDU with elevation (that you measured using the laser range finder when you made the mark points). So you don't have to worry about accuracy later on. Link to comment Share on other sites More sharing options...
kontiuka Posted April 14, 2014 Share Posted April 14, 2014 We can drop JDAMs only onto a SPI, but what that SPI is and where it came from is not relevant. Using markpoints for that usually only makes sense if you want to prepare several targets before running in. And the nice thing with markpoints is, that they are stored in the CDU with elevation (that you measured using the laser range finder when you made the mark points). So you don't have to worry about accuracy later on.Yup. Mark points are pretty handy for that. Only drawback is when the targets move after the first bomb hit. Link to comment Share on other sites More sharing options...
Flagrum Posted April 14, 2014 Share Posted April 14, 2014 Yup. Mark points are pretty handy for that. Only drawback is when the targets move after the first bomb hit. JDAMs are always suboptimal if you have to deal with moving targets, no matther what. That is when LGBs come in handy. edit: disregard ... after re-reading you posting, I now understand what you meant. Yeah, markpoints usually don't help much if the target moves away from it ... for whatever reason. :o) Link to comment Share on other sites More sharing options...
Yurgon Posted April 14, 2014 Share Posted April 14, 2014 I also didn't know you could drop JADAM's on markers instead of a SPI, so where in the manual does it explain this? Thanks! Sorry, my bad. What I meant was: 1. Set TGP as SPI generator 2. Create markpoint 3. Slave TGP to steerpoint 4. Set markpoint as steerpoint 5. Run in and release (guided) bomb The bomb in this example will of course be released on the SPI. If the markpoint from step 2 is perfectly on target, then the SPI should be right on target. By creating markpoints on 6 targets, I was able to drop a JDAM on each of them in a single pass in less than 15 seconds (in a training mission with all targets nicely spaced and aligned). I simply had to switch to the next markpoint after each weapon release. If the markpoints had not been perfectly spot-on, I would have had to adjust the SPI before dropping each of the JDAMs, and that would have taken more time. That's why using the laser to get an accurate range to target is most important in this markpoint scenario. Link to comment Share on other sites More sharing options...
kontiuka Posted April 15, 2014 Share Posted April 15, 2014 Setting the SPI with the laser prior to the run in will not increase the accuracy of any LGB dropped from a high pass. Even setting it for JDAMs is pointless, because as Yurgons has said the SPI will continuously update, so as soon as you turn the laser off, your SPI will update and you have lost your so called "extra accuracy".I just ran some more tests and I can confirm this is true. Turning the laser off will return the TGP to pointing to the terrain behind the target. I actually watched the TGP cursor in my TAD while I toggled the laser on and off and I could see the TGP cursor shift slightly back and forth. I would say, for JDAMs, it's advantageous to turn the laser on just before release and turn it off just after release so that the JDAM is given the most accurate position and elevation data. LGBs are obviously different since they ride the laser to the target anyways. Link to comment Share on other sites More sharing options...
Kaiza Posted April 15, 2014 Share Posted April 15, 2014 (edited) I just ran some more tests and I can confirm this is true. Turning the laser off will return the TGP to pointing to the terrain behind the target. I actually watched the TGP cursor in my TAD while I toggled the laser on and off and I could see the TGP cursor shift slightly back and forth. I would say, for JDAMs, it's advantageous to turn the laser on just before release and turn it off just after release so that the JDAM is given the most accurate position and elevation data. LGBs are obviously different since they ride the laser to the target anyways. I can see how this particular technique would improve your SPI position, but I believe the same effect can be achieved by being smart about where you point your TGP. By aiming the TGP at the base of the target, ie where the wheels/tracks/base meet the earth rather than the top or side of the target you will nullify any grazing angle inaccuracies meaning the laser is not required which will in turn simplify the weapon release procedure. Thats personally how I prefer to attack with JDAM but each to their own I suppose. Obviously in RL (and future CA modules perhaps?) using a laser will potentially alert the enemy. Edited April 15, 2014 by Kaiza [url=http://www.aef-hq.com.au/aef4/forumdisplay.php?262-Digital-Combat-Simulator][SIGPIC]http://img856.imageshack.us/img856/2500/a10161sqnsignitureedite.png[/SIGPIC][/url] Link to comment Share on other sites More sharing options...
kontiuka Posted April 15, 2014 Share Posted April 15, 2014 I can see how this particular technique would improve your SPI position, but I believe the same effect can be achieved by being smart about where you point your TGP. By aiming the TGP at the base of the target, ie where the wheels/tracks/base meet the earth rather than the top or side of the target you will nullify any grazing angle inaccuracies meaning the laser is not required which will in turn simplify the weapon release procedure. Thats personally how I prefer to attack with JDAM but each to their own I suppose. Obviously in RL (and future CA modules perhaps?) using a laser will potentially alert the enemy.Ya, I'd agree with that. Do you target in INR-P mode? I find in Point mode, the TGP usually locks on the centre of the target, not the base. Link to comment Share on other sites More sharing options...
Saruman Posted April 15, 2014 Share Posted April 15, 2014 Obviously in RL (and future CA modules perhaps?) using a laser will potentially alert the enemy. Is the laser visible to human eyes in RL? I don't know why, but I always thought it's not (but never checked for that, so no surprise I was wrong). Link to comment Share on other sites More sharing options...
txmtb Posted April 15, 2014 Share Posted April 15, 2014 Is the laser visible to human eyes in RL? I don't know why, but I always thought it's not (but never checked for that, so no surprise I was wrong). IRL, vehicles can have a laser warning receiver that alerts the crew when they are being lased. CA could have that modeled similar to the RWR in aircraft. Win 10 64 Pro, MSI Z390 I7-9700K @5ghz Kraken Z63, 32Gb Corsair Dominator, MSI RTX-2070, 1TB NVME 2TB SSD's, TM Warthog, Pro Rudders, OpenTrack w/ IR Clip Link to comment Share on other sites More sharing options...
Saruman Posted April 15, 2014 Share Posted April 15, 2014 Oh, I see. Thanks for the link! Link to comment Share on other sites More sharing options...
baltic_dragon Posted April 15, 2014 Share Posted April 15, 2014 Is the laser visible to human eyes in RL? I don't know why, but I always thought it's not (but never checked for that, so no surprise I was wrong). Fly a night mission, employ your laser and then turn on the your night vision goggles. Can't see it without them, but with proper equipment it is visible. Link to comment Share on other sites More sharing options...
Kaiza Posted April 15, 2014 Share Posted April 15, 2014 Ya, I'd agree with that. Do you target in INR-P mode? I find in Point mode, the TGP usually locks on the centre of the target, not the base. No I use area mode for that exact reason. Point mode is only really needed for moving targets and obviously you won't be dropping JDAM on a moving target. Fly a night mission, employ your laser and then turn on the your night vision goggles. Can't see it without them, but with proper equipment it is visible. What you are seeing is the IR pointer, not the laser. The laser is not visible, although it will damage a human retina if you shine it in someone's eyes. That is why there is a "train" mode on the laser which reduces the power of the designator to avoid causing damage to people's vision during training. [url=http://www.aef-hq.com.au/aef4/forumdisplay.php?262-Digital-Combat-Simulator][SIGPIC]http://img856.imageshack.us/img856/2500/a10161sqnsignitureedite.png[/SIGPIC][/url] Link to comment Share on other sites More sharing options...
baltic_dragon Posted April 16, 2014 Share Posted April 16, 2014 What you are seeing is the IR pointer, not the laser. The laser is not visible, although it will damage a human retina if you shine it in someone's eyes. That is why there is a "train" mode on the laser which reduces the power of the designator to avoid causing damage to people's vision during training. I stand corrected! Link to comment Share on other sites More sharing options...
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