UAS Integration in the NAS

Activity 3.5

            Much like our nation’s roads has experienced with cars, our National Airspace (NAS) has become increasingly congested as more and more aircraft are crowding our skies. To combat this issue, the Federal Aviation Administration (FAA) has developed a plan of action to increase efficiency and safety within our NAS. This plan of action is known as NextGen. NextGen encompasses a shift from the traditional ground based navigation system currently employed within the NAS to a satellite based navigational system. Currently, the aircraft in our skies fly inefficient indirect routes that waste fuel and time and congest our nation’s airports. The implementation of NextGen between 2012 and 2015 is expected to save billions of dollars in the long run, while increasing efficient use of airport capacity and ground movement, enabling more efficient direct flights and approaches/departures that are safer, reducing delays and costs associated with traffic and maneuvering and reduce stacking at airports. Ultimately, reducing gridlock and increasing the efficient utilization of our NAS will enhance safety and provide additional needed airspace capacity (Federal Aviation Administration, 2013).

Specifically, the goals of NextGen include increased efficiency and advancement of:   “Trajectory-based operations, arrivals/departures at high-density airports, flexible terminals and airports as well as optimized profile descent” (Federal Aviation Administration, 2009). These evolutions will be dependent on Performance-Based Navigation (PBN), which is a framework of performance requirements and are comprised of two main components- Area Navigation (RNAV) and Required Navigation Performance (RNP). “RNAV enables aircraft to fly on any desired flight path within the coverage of ground- or spaced-based navigation aids, within the limits of the capability of the self-contained systems, or a combination of both capabilities” (Federal Aviation Administration, 2009). RNP is essentially RNAV with additional on-board performance monitoring and alert capability (Federal Aviation Administration, 2009).

Unmanned Aircraft have proven to be a challenge for integration into the future NAS, as proven and realistic sense, detect and avoid technologies can sometimes be inhibitive or cost preventative to low weight performance UAS. The added weight of proven cooperative systems such as Traffic Collision Avoidance Systems (TCAS) can restrict the capability of the system, and may not be able to adequately relay required communication. These systems also typically require other aircraft to be equipped with the technology for it to be effective. Non-cooperative active technology such as radar and lasers, or passive technology, such as motion sensing and infrared are increasingly being utilized or incorporated into UAS (Barnhart, Shappee & Marshall, 2011). Lost link conditions are another area of concern, as failure for the UAS to adequately follow flight rules in the case of a lost link has the potential to create a dangerous situation (Mullins, 2012).

Besides the Sense Detect and Avoid issues that can present dangerous situations, one major area of concern for the NextGen system and integration of UAS into the NAS is the difficulty of monitoring and tracking of the aircraft and their associated flight plans. Traditional manned aircraft flight plans are tracked from point to point, which is what the computers are designed to monitor. UAS have the unique ability to remain aloft for days, weeks or potentially years. Additionally, these aircraft also typically fly at a slower pace that other commercial aircraft which may cause additional congestion and avoidance routing (Robertson, 2014).

References

Barnhart, R. K., Shappee, E., & Marshall, D. M. (2011). Introduction to Unmanned Aircraft Systems. London, GBR: CRC Press. Retrieved from http://www.ebrary.com

Federal Aviation Administration. (2009, April 24). Fact Sheet – NextGen Goal: Performance-Based Navigation. Retrieved from http://www.faa.gov/news/fact_sheets/news_story.cfm?newsId=8768

Federal Aviation Administration. (2013, January 14). NextGen – What is NextGen? Retrieved from https://www.faa.gov/nextgen/slides/?slide=1

Mullins, R. (2012, April 25). UAV Sense-And-Avoid Called Biggest Challenge To Integration | AWIN content from Aviation Week. Retrieved from http://aviationweek.com/awin/uav-sense-and-avoid-called-biggest-challenge-integration

Robertson, A. (2014, September 25). FAA says air traffic control isn't ready for drones | The Verge. Retrieved from http://www.theverge.com/2014/9/25/6843303/faa-says-air-traffic-control-isnt-ready-for-drones