US bunker buster bombs vulnerable to anti-aircraft shells, claim China's scientists

Yahoo

20-07-2025

Chinese military scientists have proposed a way to counter the US Air Force's famed GBU-57 Massive Ordnance Penetrators (MOP) or bunker busters by revealing an alleged flaw with their design.
In a study published in China's Journal of Gun Launch and Control, researchers led by Cui Xingyi from the country's Northwest Institute of Mechanical and Electrical Engineering, found a potential weakness in the GBU-57. The study noted that while the MOP's nose is heavily reinforced, its steel sides are just a few centimeters thick, making the weapon vulnerable to anti-aircraft shells.
Using computer simulations, the team tested Swiss Oerlikon GDF guns, widely used in the Middle East, including Iran. These guns can fire 36 shells in two seconds, with a 42% kill probability at 1,200 meters.
However, the researchers cautioned that this countermeasure requires precise radar tracking, effective electronic warfare strategy, and defense against any incoming attacks.
Vulnerable to side strikes
On June 22, when the US B-2 stealth bombers launched the GBU-57 bunker busters against Iran's nuclear sites, reports suggested that the strikes faced minimal resistance. These powerful bombs, designed to penetrate deep underground bunkers, successfully hit their targets without encountering significant air defenses or interception attempts.
However, Chinese researchers explain that while the GBU-57's egg-shaped nose deflects direct frontal hits, its sides betray a vulnerable area which could be shattered by a couple of anti-aircraft projectiles.
For a shell to penetrate, it must strike at an angle under 68 degrees; otherwise, it will simply glance off. Tests show that penetration fails beyond 4,900 feet; but within 3,900 feet, heat and shrapnel can ignite the bomb's inert explosives, the South China Morning Post reported.
The method relies on basic World War II armor-piercing calculations. But, there is a tactical challenge: the interceptors must be pre-aimed at a specific point along the MOP's flight path. The closer this aim point is, the more stable the barrels remain, a strategy researchers call 'sniper fire control' tactic.
Strategy comes with caveats
Cui's team noted that this sniper-style interception method offers several key advantages. Pre-aiming the guns at a specific point along the bomb's path reduces the demands on the servo systems and removes the need for repeated calculations, cutting the response time down to just 1 millisecond.
The researchers also emphasized that this approach is feasible with existing technology, making it a practical option for quickly targeting and neutralizing incoming bunker buster bombs.
However, while these sniper-style interception tactics sound promising in theory, the realities of combat are far harsher. Air forces can launch mass raids to destroy anti-aircraft interceptors before bomber missions begin, eliminating any potential defense.
Additionally, smart bombs often perform final manoeuvres just before impact, making their flight path unpredictable and limiting the opportunity to target within the narrow 3,900-foot effective range, which only lasts for a split second.
Furthermore, study experts also cautioned that strategies developed for China's defense systems may not be effective in other regions due to differences in terrain, threat environments, and available technologies.