Masters Theses

Date of Award


Degree Type


Degree Name

Master of Science


Aviation Systems

Major Professor

Richard Ranaudo

Committee Members

U. Peter Solies, Rodney Allison


Currently one of the most arduous and dangerous aviation missions for the military attack helicopter pilot is the night combat mission. The mission entails flight at close proximity to the ground and obstacles such as wires, trees, and buildings in an effort to avoid detection by enemy air defense and insurgent small arms fire. Night flight requires the use of augmented vision systems and enhanced aircraft stability and control systems to allow pilots to effectively see and negotiate those hazards that would otherwise be visible during daylight.

The U.S. Army currently fields two variants of augmented visionics, the Aviator Night Vision Imaging System (ANVIS) and the Pilot Night Vision System/Target Acquisition and Designation System (PNVS/TADS). ANVIS is a portable Image Intensification (I2) system usable by all Army airframes whereas PNVS and TADS are both forward looking infrared (FLIR) subcomponents attached to the nose of the AH-64 attack helicopter. Since aviators began using augmented vision systems complaints have been registered regarding loss of static and dynamic cues, presence of visual illusions and other visual symptoms. Currently the mission has grown to encompass urban and suburban reconnaissance and security operations using systems designed in the late 1970’s for transitioning to a "battle position" and near stationary engagement of heavy armor forces.

This study evaluated both systems in use by AH-64D aviators serving in and around Baghdad, Iraq from November 2005 thru October 2006. Whereas previous studies concentrated solely on visual symptoms and complaints associated with IHADSS use, this was the first study of both the FLIR and I2 used in combination by AH-64 cockpit crews.

In the constant-moving environment of aerial reconnaissance and security, I2 is preferable to the IHADSS by a majority of AH-64D pilots. Additionally, results showed a predominant favoring of the ANVIS over the PNVS/TADS for wire and aircraft avoidance due in large part to the enhanced visual acuity (20/25) of the ANVIS as compared to the 20/60 visual acuity of the IHADSS. The visual acuity disparity led to consistent reporting of insufficient visual cues by IHADSS users. The primary benefit, as seen by pilots, of the PNVS/TADS system was the flight symbology cues provided through the helmet mounted display. Through training and education the data is received as stimuli and converted into usable 3-D cues for improved situational awareness. As with all previous studies, visual symptoms associated with IHADSS use were present.

Files over 3MB may be slow to open. For best results, right-click and select "save as..."