Publication Date


Document Type


Committee Members

Jennie Gallimore (Advisor), Clark Shingledecker (Committee Member), Ganapathy Subhashini (Committee Member)

Degree Name

Master of Science in Engineering (MSEgr)


Air Traffic has shown a steady increase since the institution of commercial aviation in the first quarter of the last century, and the use of the United States National Airspace System (NAS) is expected to increase by 45 percent more passengers by the year 2015 (Smith, 2004). The increasing demands of the NAS require preventive measures in order to preserve the safety of operations. NextGen is a transformative program expected to enhance the safety and effectiveness of NAS operations. One of the ways that it will achieve these goals is by improving air-ground communications.

In the current system, communications between pilots and Air Traffic Control (ATC) is accomplished via voice radio; controllers have the task of communicating clearance information to aircraft in their designated airspace. This method of communication proves to be effective when used during urgent situations utilizing short messages. Voice communication can be ineffective and inefficient under various other circumstances. For example, message length and complexity can burden pilot memory. For NextGen, the use of data link allows for the creation of data communication (DataComm) messages and clearances sent directly to flight deck displays, thereby reducing the need for voice. DataComm will enable future communication systems to relieve the pilot from retaining immediate fight path information as it is communicated. This information may overload their cognitive processing abilities resulting in a reduced ability to make accurate and correct decisions.

There have been several studies evaluating the effects of DataComm using textual message displays on the flight deck. To date there is no evidence of major research investigation of the use of graphics and or hybrid techniques for DataComm message display .

The objectives of this research were to investigate the effects of text and graphics formats on pilot interpretation of spatial clearances given en route. Pilot performance was evaluated for five communication formats (TEXT only, Graphics+Text, Graphics+Text+updated UM, Graphics+Text+Altitude Situation Display, and Graphics+Imbedded Text+Altitude Situation Display). The performance measures were time to interpret an uplink message (UM) from ATC, and percentage of correct responses, including correct acceptance and correct rejection of a clearance. The findings indicated that there are statistically significant differences in pilot performance when using graphics to communicate ATC uplink clearances. As the number of elements in a clearance increased, pilot performance with respect to response time and percent correct was significantly improved with combined graphics and text formats compared to a text-only format.

Page Count


Department or Program

Department of Biomedical, Industrial & Human Factors Engineering

Year Degree Awarded