Even while the F-22 is equipped with both guns and missiles, only the approximately $400,000 AIM-9X guarantees the ability to destroy targets with a narrow radar cross area, such as a balloon.
A Chinese airship was destroyed by an AIM-9X Sidewinder missile fired from an American F-22 stealth fighter on February 4. While China maintained that the balloon was a civilian one used for meteorological research, the US military’s defence establishment suspected otherwise and accused China of using the balloon for spying.
The US military began considering shooting down the balloon in the middle of last week. Two F-22 stealth planes were sent all the way from the Nellis base in Nevada, some 1,100 kilometres away from South Carolina, to carry out the operation.
Because the F-22 can fly higher than older fighters like the F-15 and F-16, it can get more detailed information on the balloon through its cameras.
For its air defence role, the F-22 stealth fighter is equipped with a 20mm M61 gun, a short-range surface-to-air missile (AIM-9X Sidewinder), and a medium-range air-to-air missile (AIM-120C/D AMRAAM). Most military analysts agree that the AIM-9X missile, which costs close to $400,000, is the best choice for the United States to shoot down the airship.
“Shooting down balloons at such a high altitude is not a small challenge. They pose a lot of problems with the missile’s guidance system,” wrote expert Tyler Rogoway on the US military website War Zone.
It is nearly impossible to track and lock the target using conventional methods due to the airship’s extremely weak radar and heat signal. A single balloon’s radar reflection area is roughly the same as that of a bird. They’re in motion, too.
“Moving very slowly compared to typical flying targets, making them often not detectable by contemporary Doppler radars,” says a report published by the Air Force Research Institute (AFRI) of the US Air Force in 2005.
Even if the fighter aimed and fired, the missile may pass through the balloon’s outer shell without exploding. This makes it more challenging to collect the equipment, as the balloon is less likely to fall to the ground and more likely to stay floating in the air.
In order to destroy or severely damage the enemy’s armaments, most modern air-to-air missiles are equipped with a near-target fuse that causes the missile to detonate near the target. Short-range AIM-9X projectiles use lasers, whereas longer-range AIM-120 missiles use radar-activated near-target fuzes.
“Due of the limited radar reflection area of a balloon, the AIM-120 missile’s radar-activated near-target detonator may not work, resulting in the project continuing to fly freely until it self-destructs or crashes to the ground. The AIM-9X’s laser fuse is better suited for this task “said Rogoway.
While the F-22’s 20mm cannon is certainly less expensive than the AIM-9X missile, it is not without its drawbacks. Because the F-22’s M61 gun has a 600-meter effective range, it must approach the balloon quite closely to fire.
Due to the airship’s operating height of around 18.3 km and the F-22’s ceiling of 18 km, the US aircraft cannot approach the target at a diving angle.
If the plane can’t get high enough to shoot down the balloon, it has to turn its nose up. Threatening safety, the bullets can travel in an arc for kilometres before crashing to the ground over a wide area.
Experts in the United States have voiced concern that the F-22’s poor low-altitude manoeuvrability may make it more challenging for pilots to maintain aim when firing weapons like artillery shells that lack guidance systems.
The 20 mm cannon’s fragmentation shell is inactive against the airship’s thin shell but goes off against solid material like an airplane’s fuselage or engine.
While the use of non-explosive, non-armor-piercing training ammunition may lessen the likelihood of an accident, it does not ensure that the balloon can be shot down immediately.
After more than a thousand rounds from 20 mm cannon were shot at the weather balloon from a distance of less than 12 km by CF-18 aircraft of the Canadian Air Force in 1998, the balloon did not come to rest but instead continued to move. Days that effect transatlantic flight schedules.
“Bombarding the equipment hangar below could disable the airship but would cause more debris to fall along its flight path, as well as limit its ability to gather intelligence after it’s down. The small size of this compartment makes it difficult for pilots to aim accurately,” Rogoway said.
The US military had no option but to shoot down the balloon with an anti-aircraft missile because only the Patriot system could destroy such high-altitude targets in the atmosphere. However, reconnaissance complexes and Patriot missiles also have problems due to the balloon’s very small radar reflection area.
There are no Patriot batteries in a state of readiness to fight on US soil; apart from a number of complexes used for training and testing, the deployment process also takes a long time and cannot keep up with the movement of the enemy Chinese airship.