Vision of NextGen
|(Video embedded from YouTube on 3 Oct 2009)|
With the dawn of the new millennium, research has shown that the exponential increase in air travel has given rise to a myriad of problems with respect to air capacity. This has resulted in increased delays, environmental degradation and decreasing safety standards in aviation.
- This is due to air travel not being able to meet the high public expectations what with the loads of delays and long waiting time on the tarmac.
- Air traffic is also over taxed and is near capacity; with new aircraft being introduced, more low cost airlines sprouting up, safety could be potential compromised with the continued use of existing technologies in managing.
- There is also presently substantial noise generated, fuel being wasted and increasing carbon emissions due to longer than necessary routes taken in getting from point to point destinations.
NextGen, a revolutionary air transportation system utilising the latest, modern technologies, which is the brainchild of FAA, NASA and other US government bodies promises to solve these problems and make air travel efficient, safe and environmentally friendly by its full implementation in the US between 2018 and 2025. 
How will NextGen work
Surveillance through Technology
With the latest state-of-the-art technologies such as Automatic Dependent Surveillance - Broadcast (ADS-B) and Airport Surface Detection Equipment (ASDE); a common air/ ground picture will be shared by both pilots and ATC.
Dependence on ATC
- Currently, pilots are dependent on ATC to provide traffic information as they are not able to view the same radar picture as ATC with regard to the number of aircraft that is within the vicinity along with its characteristics such as height and speed.
- ADS-B will provide pilots with the latest GPS updates by broadcasting other aircraft's positions to the cockpit, enhancing detection of other planes precise location and performance. Pilots now will have greater situational awareness and are able to make better decisions with regard to traffic avoidance.
- ADS-B can also recommend pilots to fly an optimum path of air traffic and use airspace more efficiently as it is more precise than radar. Presently, aircraft are bounded by air corridors (which "regulates" traffic in a uniflow manner) and existing radar separation standards.
- With up-to-date position on the maps, which navigational aids are available and where are the nearby airports for diversion if required, decisions can be made to get to destinations safely and more directly, thus reducing the dependency of radar vectors by ATC.
- This would mean ATC can increase the number of aircraft to handle as pilots can fly closer together with continuous updates from GPS and reduced separation standards.
- On the ground at airports, ASDE would help to eliminate runway incursions as it provides up-to-date ground traffic information for controllers and pilots to track aircraft and vehicular movements.
- Hence, better situational awareness would prevent aircraft collisions on the ground as pilots and controllers would know where the other is even in adverse weather.
- Another feature would be pilots and ATC having a common weather picture, showing the image of storm activity well ahead which would also enable pilots to make better decisions to avoid the weather and the best route to take. 
The two incidents below illustrates scenarios in which mistakes in ATC and a lack of a common air picture contributed to disastrous results. These could have been averted if NextGen had been in place.
- In the mid air collision between Aeroméxico Flight 498 & Piper 4891, radar could not pick out the Piper 4891 in the control zone and as such could not provide appropriate traffic deconfliction. The Piper 4891, on his part was also unfamiliar with his geographic location and wandered into restricted airspace.
- With NextGen and ADS-B, the positions of both aircraft would have been broadcasted to both pilots and ATC; The Piper 4891, using up to date maps would have known the boundaries of restricted airspace and even if he had deviated into it, he could have been spotted by both ATC and Aeromexico Flight 498 so that avoidance action well in advance could have been taken.
For a more comprehensive analysis of the incident, please refer to Mid Air Collision between Aeroméxico Flight 498 & Piper 4891
- In the second incident involving a mid air collision between Bashkirian Airlines Flight 2937 & DHL Flight 611, a momentary lapse of concentration in monitoring the radar screen allowed two aircraft to converge at the same altitude. Although these two aircraft were equipped with TCAS, the conflicting manner in which the different sets of crew reacted to it were also contributed factors to the collision.
- Similarly to the first incident, NextGen and ADS-B would have allowed a common air picture to have been known to both pilots well in advance so that they would have been warned they were on a conflicting course so that they could have taken different paths or even alerting the controller.
For a more comprehensive analysis of the incident, please refer to Mid Air Collision between Bashkirian Airlines Flight 2937 & DHL Flight 611
- The problem with current day to day communications arise out of misunderstandings between pilots and ATC; this involve the lack of clear and precise language, different accents, bad pronunciation, proficiency in English language and missing out on passing vital information.
- With the use of digital text based technology to the cockpit in the form of electronic data, information can be passed between ATC and pilots in a form similar to text messaging.
- This would eliminate radio chatter, reducing the need to communicate so frequently especially when traversing through different airspace sectors, thus minimizing error. 
- The incident below illustrates a case in which miscommunications between pilots and ATC contributed to the crash of Avianca Flight 52 due to failure in passing vital information that the aircraft was reaching emergency fuel and also the language barrier that hampered communications between the two parties.
- With the use of electronic data, once the correct data is keyed in by the pilots to the controllers, there would be no ambiguity in the problem of the aircraft. ATC would know the severity of the situation without having to keep interrogate the pilots due to the lack of understanding of the accent or language.
For a more comprehensive analysis of the incident, please refer to Avianca Flight 52: Deadly Delay
- Presently, aircraft are prone to circling round the airport whilst waiting for clearance to set course; with Continuous Descent Arrival (CDA) piped with ADS-B, order of arrival of aircraft are planned and sequenced well in advance (100nms) without conflict.
- Hence, each aircraft will have smooth, tailored descents, keeping it at an efficient altitude before it begins its gradual descent to the airport. This would enable aircraft to save fuel and reduce noise as profiles are flown without repeatedly playing with engine and power settings.
- Delays on the ground can also be reduced with flight planning and implementation of precise departure paths. This would improve the traffic flow at airports as there are now continuous and multiple departures routings, enabling aircraft to attain cruise altitudes as quickly as possible, thus saving time and fuel. 
The benefits of NextGen have been extolled and the technologies that are the foundation for NextGen are currently in the testing phase. The US and the world waits with baited breath for its implementation in the hope of for a more efficient aviation experience that is safe and environmentally friendly.
The two videos below provide a good summary, highlighting the key points of NextGen.
|(Video embedded from YouTube on 7 Oct 2009)||(Video embedded from YouTube on 7 Oct 2009)|
Want to know more?
- FAA's NextGen. Implementation Plan 2009
- This article page provides details on FAA's plans and efforts to develop and implement NextGen.