loki1120 wrote:please do good sir
EDIT: This is in regards to the LJDAM, the laser-guided/assisted version. The standard JDAM works similar as mentioned below, but instead of acquiring the laser source it instead just picks up the GPS signal and homes in to that location. The LJDAM usually only activates the laser portion of the guidance system if the GPS signal is lost, if the target is moving slowly, or if the exact point of impact needed has changed after release. JDAM munitions can not change their target coordinates after release, there is no magic update feature. Release heights are still about the same for both the JDAM and LJDAM models.
Well, basically like any other laser-guided munition, they use a seeker head that is able to look downwards onto the target area in a cone-like view. As long as the laser designator beam is within this cone of view and the frequency is coded into the munition, it can track the beam and ride it home.
The catch is that the munition must be fired from a high enough altitude and released from the correct angle in order to get the "cone" within the area of the target and the laser mark. If the munition is dropped too low, the cone is too small. If the munition is dropped too fast, the cone will overshoot the target area or the munition will be traveling too fast to be capable of steering itself while still keeping the cone in the target zone.
This means that aircraft needing to use laser-guided munitions must drop them from a high enough altitude to give the munition's cone enough range to allow maneuvering and ensure a good hit. The higher the release, the wider the bottom of the cone's radius. This is generally done at altitudes of FL200 to FL300 (20,000 to 30,000 feet), and the higher the altitude then the more precise the weapon will be.
The problem with using the JDAM on aircraft in PR is that the pilots (players) will not be flying their aircraft at a realistic height in order to use the JDAM effectively. In all honesty, the height at which PR aircraft operate would actually make the use of any LGB munitions unrealistic. At those heights, they would be engaging targets with either a CCIP or CCRP targeting method, using non-laser munitions. Low-flying aircraft like the A-10 would also have a higher chance of sticking to their other guided munitions such as the AGM-65.
Another issue with releasing a large munition at low-altitude is the fact that if the munition is not retarded, there is the chance that the detonation could cause a portion of the blast wave or fragments/debris to strike the aircraft as it makes its pass. An example would the the Mk 82 Snakeye.
In real combat, the decision to use a JDAM munition must be weighed against the individual theater and circumstances. Due to the high altitude required for JDAM release, this puts the aircraft at risk of SAM hits. You will usually have a SEAD strike in the area before any such JDAM runs, and even then there is still risk of hidden or "silent" SAM sites will become active. This is why we have several other precision weapons available, such as the infamous "cruise missile" and the 155mm Copperhead munition. If the area is unsafe for air release, these other methods would be used instead.
People need to realize that the 2000-pound JDAM munition is not going to be used against troops, and will probably not be used against armor or other vehicles. A smaller munition payload is capable of taking out those targets with much less risk of collateral damage, and at a much cheaper price tag. The 2000-pounders are often reserved specifically for engaging hard targets such as bunkers, caves, factories, or other structures that a lighter payload might not be capable of defeating even with a penetrating fuze.
The JDAM was designed for precision strikes against stationary targets, usually those that were not capable of being engaged by other means without putting soldiers or equipment at risk or when other munitions would not be effective.
So for those wondering why we have a JDAM in PR, it's to offer the team a limited-use (either by time delay or quantity) precision-strike weapon with a payload larger than what is normally available on aircraft of that map. Examples of proper PR JDAM use would be when you have a bunker or base that needs knocked out and flying an attack sortie with low-alt aircraft would be too risky, or if you need to hit a precision target and no other immediate support is available. And I'm talking about life-and-death win-or-lose targets here like a group of armor or the enemy building an FB right outside your camp. You should not be using the JDAM to smash a single tank or flatten just one squad of infantry. This is what the other assets are for.