A
system and apparatus for acquiring images of electric
transmission line tower structures, equipment attached to said
tower structures, and transmission lines suspended from said towers. The
system uses a
fixed wing aircraft and an arrangement of at least one
still camera, means for detecting a
tower structure, a data storage unit, and a
central processing unit containing operational
software. The
central processing unit is connected to the camera, the means for detecting a tower structure, and the storage unit. The detection means is a
laser altimeter or a combination of preset
longitude /
latitude coordinates for tower locations and a GPS unit which supplies continuous
longitude /
latitude coordinates for the aircraft location for comparison to those preset coordinates. The aircraft is flown along the
transmission line at a predetermined altitude above the tops of said towers (60–100 feet). The
still camera points rearwardly relative to the line of flight of the aircraft and take a picture from between two adjacent towers and along an
exposure line directed downwardly at an angle to the line of flight, 30–60 degrees and preferably 45 degrees. The detecting means transmits a
signal to the central
processing indicative of the presence of a tower to be photographed. The
central processing unit calculates the time
delay necessary for said aircraft to fly past the tower to a predetermined
exposure point located between the tower to be photographed and the next tower in said
transmission line after the tower to be photographed. The
still camera is activated at the
exposure point to acquire an image of the tower structure. The data corresponding to the acquired image is transmitted to a data storage unit for later retrieval and examination to identify defects in the tower or the equipment or transmission lines suspended form the tower. The
system is reset to continue acquiring images along the transmission lines. The system is also provided with a video capability to film the towers and transmission lines and the line right-of-way.