Would multiple bunker busters really do more damage if they aren't going deep enough
Executive summary
Multiple smaller or repeated bunker-buster strikes can increase overall damage when a single weapon cannot reach the protected depth or to defeat layered defenses; depth capability depends on weapon model and ground material — reported penetration ranges run from under 2 feet (BLU-109) to claims of up to ~200 feet for the GBU-57/MOP [1] [2]. Experts and reporting note that penetration is limited by soil/rock/concrete hardness and that effects can be achieved by producing destructive shock waves or targeting auxiliary systems even when full structural collapse isn’t achieved [3] [4].
1. Why “drilling” with multiple bombs is a plausible tactic
Dropping multiple bunker busters in the same shaft or sequence is a tactic discussed in contemporary reporting: successive penetrations can exploit an initial cavity or weakened concrete to let later charges go deeper or to collapse protective layers that a single strike cannot breach (news graphics and operational descriptions referenced in reporting on recent strikes) [5] [2]. JINSA commentary and news coverage of operational planning explicitly note commanders weigh using multiple 5,000‑pound-class bombs or very large MOP‑class weapons in numbers based on facility depth and construction [6] [2].
2. Limits set by weapon design and materials encountered
Penetration is fundamentally a function of warhead mass, casing strength, impact velocity, and the medium it hits. Different munitions have very different real-world ranges — examples cited in recent journalism put BLU‑109s at shallow penetration and large designs like the GBU‑57/MOP described by the Air Force as able to reach “up to 200 feet,” though exact classified performance varies [1] [2]. The New York Times analysis reiterates that “maximum penetration depth” depends on what the bomb encounters — dense concrete and hard rock sharply reduce depth compared with soft soil [3].
3. Why one “deep” weapon is not a guaranteed solution
Even very large penetrators face geologic and engineering countermeasures. Reporting on the GBU‑57 notes advanced fuzes and preprogrammed detonation depths designed to optimize effect, yet analysts flag that ultra‑hard concrete (and variable rock like limestone) can defeat or blunt penetration and that builders deliberately harden key facilities to reduce weapon effectiveness [7] [3]. Wikipedia summaries of penetrator theory and the use of rocket‑boosted penetrators underline that speed and high‑density design help, but are not absolute guarantees against super‑hardened sites [8].
4. Alternative effects besides “burrowing to the room”
Sources describe multiple pathways to mission success besides literally reaching the central chamber: detonating at or near the facility depth can transmit shock waves through rock, cause “scabbing,” or fill/disable ventilation, power or access points, making operations (like centrifuge operation) impossible even if core infrastructure remains partially intact [4] [6] [3]. Analysts and operators therefore consider “success” as degrading or denying the site’s function, not always total physical destruction [6].
5. Conflicting claims and secrecy — what the public record shows
Public figures for penetration differ: some outlets quote Air Force claims of “up to 200 feet” for the MOP while other analyses and historical analogs produce lower estimates or ranges (e.g., BLU‑109 “just under 2 feet,” other large penetrators tens of feet) [1] [2] [5]. Independent technical estimates and community analysis note that figures can be optimistic and that many exact performance numbers remain classified; reporting and commentary therefore offer competing interpretations rather than a single certitude [5] [9].
6. Practical takeaway for the original question
Available reporting supports the conclusion that multiple bunker‑busters can produce greater effect when a single bomb won’t reach or destroy a hardened target — by exploiting cavities, weakening layers, or producing cumulative shock and debris effects — but their success depends on weapon type, fuze/sensing tech, and the geology and construction of the target [6] [3] [8]. Sources do not provide an unambiguous, empirical formula that “x bombs = y additional feet”; exact effectiveness in any scenario remains dependent on classified performance data and the local materials and engineering of the bunker (not found in current reporting).
Limitations and agendas: military sources emphasize capability (e.g., “up to 200 feet”) for deterrence and operational rationale [2]; think‑tank and defense outlets frame multi‑strike options as plausibly useful for achieving mission goals short of annihilating a facility [6]. Independent analyses and journalistic graphics stress geological variability and secrecy, cautioning that public claims may overstate consistent performance [3] [5].