A typical "sensor fused weapon" is a CBU-105. This ordnance weighs about 1,000 pounds and carry a whole bunch of submunitions which disperse high over the enemy, search for heat signatures from engines and such, then launch a precision missile which penetrates the enemy vehicle/armor. The system is launched from an aircraft well outside the engagement area. Sensors (observers on the ground, airborne, satellite, etc.) are networked to tell the aircraft where the bad guys are. The pilot aims his weapon into a piece of sky over the target area and pulls the trigger. The weapon takes over... approaching, identifying and attacking the target(s) with a high degree of precision.
Rockets are a different world. They are like bullets. You aim and fire. Like a bullet, they are unguided in flight and go where aimed. Rockets are an "area weapon" and not a "precision weapon". Precision weapons are guided in flight to track os moving target, either autonomously or by the gunner. Bullets and iron bombs are "dumb weapons". TOW, DRAGON and SAL HELLFIRE are "smart weapons". They are guided by the gunner during flight either by wire (as in TOW and DRAGON) or by laser (as in SAL HELLFIRE). JAVELIN and LONGBOW HELLFIRE are examples of "brilliant weapons" which guide themselves to the target. JAVELIN, for example, uses TV to identify a straight line, right angle or some other feature on the target which does not exist in nature. It "locks on" to this feature and guides itself to the moving or stationary target.
Helicopters are much better at evading enemy fire than fast movers. They both carry an IRCM suite that jams heat seekers, IR seekers and other guidance systems and the flare dispenser they both carry. But as countermeasures get better, so do the attacking weapons. The original REDEYE air defense system had to attack an aircraft from the rear where the exhaust was. (After the attacking aircraft had dropped its ordnance on you... bad idea.) The original Stinger (BASIC STINGER) allowed a front attack. The next generation Stinger (Stinger POST... Passive Optical Sensing Technique) enhanced these abilities. Then the countermeasures learned to change the IR signature so that the incoming missile couldn't see it. This led to STINGER RMP (Reprogrammable MicroProcessor) which allowed sensing across the spectrum no matter what the target did to confuse the missile.Both helos and fixed wing have these countermeasures. In that, they are equally protected. But a helicopter is comfortable flying even BELOW tree level or hovering behind a rock. Fast movers can't do that. The key is to engage the target from a position where the firing platform cannot be seen or detected. Modern aircraft, both fixed wing and rotary wing are now networked with ground, air and even satellite sensors to tell them exactly where the bad guys are without being anywhere near them. Using things like sensor-fused weapons and LONGBOW HELLFIRE, they can use this data to strike the enemy WITH PRECISION from standoff ranges which ensure their survival. Guns are simply too short range to be able to do this.
A couple of other thoughts.. the gun of an A-10 destroys armor by setting up harmonic distortions within the enemy armor. The gun does NOT PIERCE armor. It set up multiple vibrations which literally cause the metal to crack, vibrate and shake itself apart. Multiple hits are required. That means gunner exposure time... not good. Anti-armor weapons like HELLFIRE, JAVELIN and CBU-105 use "shaped cahrges" even tandem mounted multiple shaped charges which FOCUS the explosive force to actually PIERCE the armor.
And finally, Apaches are a lot more AVAILABLE than fast movers. Fast movers come from an airstrip typically far from the combat area. When I was in Iraq they came from bases far from our AO. I remember one day sitting on the roof of our Ops Center watching F-16's dropping JDAMS (laser guided bombs) on SADR City. They would drop the bombs and disappear... coming back sometime later refueled and rearmed. Meanwhile, Kiowa Warrior (OH-58D) helicopters right in front of me stayed hidden behind a tree line, exposing only their laser in its mount above the blades (MMS) to laser "designate" the targets and guide the JDAMS to their target WITH PRECISION. They took turns rearming and refueling at a mobile FAARP located about 100 yards from me. They never left the battle area. Meanwhile, Apaches attacked escaping bad guys over and over... refueling quickly and efficiently only miles away from their firing points.
The Army doesn't use Cobra;s anymore, although the last time I looked, the Marines still did. New versions with all sorts of gizmos... can even fire a Maverick and HELLFIRES.
