Researchers at the Royal United Services Institute found that during massed attacks on well-defended facilities — salvos of 100 to 150 UAVs — approximately 10 drones typically reach the target, a penetration rate of roughly 10% 1. Attack drone costs range from $20,000 to $80,000 per unit 2. At the upper end, a 150-drone salvo costs $12 million to launch; the ten drones that penetrate defences each cost $1.2 million to deliver — less than the replacement value of most military infrastructure.
The defender's cost curve depends entirely on interceptor selection. A Merops unit brings the per-interception cost within an order of magnitude of the attacking drone; a Patriot PAC-3 round at $13.5 million does not. Intercepting a full 150-drone salvo with Merops costs roughly $2 million; the same task with Patriot would exceed $2 billion. The deployment described at follows directly from this maths — volume of cheap interceptors is the only economically sustainable counter to volume of cheap attackers.
Separately, the International Institute for Strategic Studies characterised drone warfare innovation in Ukraine as "constrained" — iterative adaptation within existing military frameworks rather than a transformation of them 3. The IISS assessment pushes back against the narrative that drones have rewritten the rules of conflict. What Ukraine has demonstrated is rapid improvement within established drone categories — FPV attack, ISR, electronic warfare — not the emergence of new operational concepts. The distinction matters commercially: the investment returns are in production scale and incremental cost reduction, not in speculative next-generation platforms.
Taken together, the RUSI penetration data and the IISS framing point toward the same conclusion for the industry. A stable 10% penetration rate means both sides can plan around known parameters. For attackers, the rational response is more drones at lower unit cost — the logic behind the Pentagon's target pricing under Drone Dominance. For defenders, the answer is cheap interceptors manufactured at scale. The competitive advantage accrues to whoever produces faster and cheaper, which makes factory capacity, supply chain control, and unit economics the determining variables — not patent portfolios or platform sophistication.
