Field Mods Protect Mass Production

In WWII, William Knudsen froze factory designs and shifted upgrades to field‑mod depots so assembly lines could run uninterrupted. Ford’s B‑24 plant at Willow Run shipped aircraft fast, then in‑theater teams retrofitted improvements, avoiding redesign churn that would have stalled throughput. Adopting this 'field‑mod first' rule can prevent modern programs from dying under pre‑production change orders. — It offers a clear procurement and manufacturing heuristic for scaling drones, vehicles, and energy hardware quickly without sacrificing improvement.