The RQ-4 Global Hawk is the largest remote-controlled aircraft in the US.

The RQ-4 Global Hawk is a high-altitude, long-endurance, remotely piloted aircraft with an integrated sensor suite that provides global all-weather, day or night intelligence, surveillance and reconnaissance (ISR) capability.

Northrop Grumman RQ-4 Global Hawk – Wikipedia tiếng Việt

In the RQ-4 name, the “R” is the Department of defeпѕe designation for Reconnaissance and “Q” means unmanned aircraft system. The “4” refers to the series of purpose-built remotely piloted aircraft systems.

RQ-4 Global Hawk - Siêu máy bay do thám không người lái hiện đại nhất của  quân đội Mỹ - Tạp chí Tài chính

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