An inspection scanner [1000] is described that has a low profile construction designed to fit into tight spaces and inspect structures [10] such as weld joints [13]. Wheel frame assemblies [1100, 1200] carry a probe holder assembly [1110] with an ultrasonic (US) array [1400] that emits US beams through the structure [10] and receives reflected sound waves. The probe holder assembly [1110] extends and US beam is angled away to inspect in tight locations. The wheel frame assemblies [1100, 1200] roll on wheels [1140, 1240] that drive an encoder [1250]. Encoder [1250] provides the specific locations for the received sound waves with respect to the weld. The locations and received sound waves are used to reconstruct a signal showing imperfections inside of structure [10]. The wheels [1140, 1240] may be magnetic to hold it to the structure [10] being inspected. A brake system [1600] may be employed to hold the inspection scanner [1000] at a given location.