RagnarDa 3rd Party Developer



Join Date: Mar 2012 Posts: 1,960

Quote: some1 Originally Posted by I have a shooting range set up on a flat airfield by the sea, dive more than 5 degrees, have radar ranging indicator on the HUD, stable aim, trigger unsafe, wait few seconds for the blinking firing cue and still, the bullets consistently fall short before the target. not the flashing line but the "wings" that are displayed around the sight dot. It is more important to fire at exactly this cue (or rather 0.5 second after this cue) when using the guns, when using the rockets you can fire a little earlier and still somewhat hit the target. You are also supposed to hold the trigger for 1 second and the gun strafe will be centered around your aim point.



I think it is worthwhile to explain the standard ("short") sight for the ARAK/AKAN in Viggen since it is quite difficult to figure out (I know I had trouble understanding how it worked at first). First of all, it is important to know that it is not a CCIP-sight which shows where the rockets/bullets will hit if you fire right now (the ARAK long-range mode is like this however). It is a little piece of SAAB-oddity that has the following design-goals if you will:



1) Provide a sight solution that is as accurate as possible. This also includes limiting the amount of ammunition dispersal so the rockets will be as concentrated as possible. I think the idea was maybe that it would be used against armored ships. The solution to this is firing the rockets/guns at the latest possible point in time (when closest to the target) while still have time to pull out and not being caught in the explosion from the rockets.



2) Provide a steady aim point on the ground. If you notice the sight stays pretty much at one point relative to the ground unless you move your stick or throttle. This allows the velocity measurement function where you can track the target and measure its speed and then the sight will compensate and show where to fire to hit a moving target. This would not have been possible with a regular CCIP-sight.



It works like this (a little simplified): it takes the indicated vertical velocity (barometric - hence you should still set the QFE even though using radar measurement, the sight would spaz out if using the radar height), indicated height (barometric or from the radar) and indicated forward speed and calculates the time it will take for the plane to reach the minimum selected safe height. It subtracts the time it would take for the plane to pull up into level-flight and also a little margin for the pilot to react. Now we have the last firing time. The computer then calculates the height the plane will have when this point in time is reached. The ballistics calculations is then done using the speed, height and orientation that the plane will have when it is at this point in time and displays to the pilot an aim point that shows where the rockets/bullets will hit if the trigger is pulled at that point in time. The pilot then waits for the timer to reach last firing timepoint (wings shown) and pulls the trigger and then immediately pulls up at 5G, and if everything is correct the rockets will hit with very high accuracy while the plane just avoids getting hit by shrapnel from the explosion.



Another way to think about the sight is that it is like a velocity vector indicator that shows where you will hit once you reach the safe altitude (plus time to level out). Ooops, I just discovered that the AKAN (guns) fireing cue was displayed exactly 1 second too early. If you wait an additional 1 second before firing your solution should be accurate. This bug doesnt affect the rockets. Also, for reference, the firing cue isthe flashing line but the "wings" that are displayed around the sight dot. It is more important to fire at exactly this cue (or rather 0.5 second after this cue) when using the guns, when using the rockets you can fire a little earlier and still somewhat hit the target. You are also supposed to hold the trigger for 1 second and the gun strafe will be centered around your aim point.I think it is worthwhile to explain the standard ("short") sight for the ARAK/AKAN in Viggen since it is quite difficult to figure out (I know I had trouble understanding how it worked at first). First of all, it is important to know that it isa CCIP-sight which shows where the rockets/bullets will hit if you fire right now (the ARAK long-range mode is like this however). It is a little piece of SAAB-oddity that has the following design-goals if you will:1) Provide a sight solution that is as accurate as possible. This also includes limiting the amount of ammunition dispersal so the rockets will be as concentrated as possible. I think the idea was maybe that it would be used against armored ships. The solution to this is firing the rockets/guns at the latest possible point in time (when closest to the target) while still have time to pull out and not being caught in the explosion from the rockets.2) Provide a steady aim point on the ground. If you notice the sight stays pretty much at one point relative to the ground unless you move your stick or throttle. This allows the velocity measurement function where you can track the target and measure its speed and then the sight will compensate and show where to fire to hit a moving target. This would not have been possible with a regular CCIP-sight.It works like this (a little simplified): it takes the indicated vertical velocity (barometric - hence you should still set the QFE even though using radar measurement, the sight would spaz out if using the radar height), indicated height (barometric or from the radar) and indicated forward speed and calculates the time it will take for the plane to reach the minimum selected safe height. It subtracts the time it would take for the plane to pull up into level-flight and also a little margin for the pilot to react. Now we have the last firing time. The computer then calculates the height the plane will have when this point in time is reached. The ballistics calculations is then done using the speed, height and orientation that the plane will haveand displays to the pilot an aim point that shows where the rockets/bullets will hit if the trigger is pulled at that point in time. The pilot then waits for the timer to reach last firing timepoint (wings shown) and pulls the trigger and then immediately pulls up at 5G, and if everything is correct the rockets will hit with very high accuracy while the plane just avoids getting hit by shrapnel from the explosion.Another way to think about the sight is that it is like a velocity vector indicator that shows where you will hit once you reach the safe altitude (plus time to level out). __________________

DCS AJS37 HACKERMAN



There will always be bugs. If everything is a priority nothing is.