This proposal is for the development of a long range, multi-point non-destructive system for the detection of subsurface flaws in metallic and composite materials of modern aircraft. This system would improve the test capabilities of NASA's ground facilities, specifically the Flight Loads Laboratory (FLL). MetroLaser proposes to use a multi-beam laser Doppler vibrometer (LDV) capable of arbitrary beam patterns on the target. This system coupled with acoustic or vibration excitation would reveal changes in the stiffness of the material, which are related to internal flaws within the material. This approach, based on the well-known LDV technique, is unique and innovative in the way it addresses the measurement requirement with multiple beams in an arbitrary beam pattern for high-speed coverage of large target areas. The Phase I work would consist of modeling, analysis and experimental work to define the system architecture and the measurement strategy, and would include developing a breadboard sensor to perform proof-of-concept experiments. It would culminate with a conceptual design of a Phase II prototype.