We describe the development of a state-of-the-art airborne 3D laser radar system capable of area coverage rates in excess of 150 km2/h. The ladar testbed can operate day and night and uses a low-power, eye-safe, and covert near-IR laser transmitter and a large-pixel-format photon-counting detector array coupled with a precision, fast-scanning, beam pointing mechanism. Mission areas include wide-area down-looking high-resolution open terrain and foliage-penetrating imaging, side-looking and up-looking laser ranging and tracking, and sensor fusion with electro-optical infrared cameras and hyperspectral payloads. We describe the airborne optical systems testbed ladar system, present recently collected 3D data, and discuss testbed configurations that can support advanced imaging applications.