David Wing, Air Traffic Management Researcher, Langley Research Center, Hampton VA
- Wednesday, 01 January 2014
David Wing is the principal investigator for the Traffic Aware Strategic Aircrew Requests (TASAR) concept and software application. The cockpit technology, while taking aircraft traffic, weather, and other data sources into account, will compute trajectory changes during the flight to save pilots time and fuel.
NASA Tech Briefs: What is TASAR?
David Wing: TASAR is a near-term concept for improving aircraft operations that we’ve developed at NASA Langley. It stands for Traffic Aware Strategic Aircrew Requests. Basically, it’s putting technology on the aircraft in the cockpit that is monitoring the aircraft’s route of flight, and looking for opportunities to optimize that route with lateral and/or vertical changes, either to save time or save fuel or both. And in the process, it’s looking at the environment around the aircraft. First and foremost, we’re focusing on traffic awareness. Using airborne surveillance technology, such as ADS-B [Automatic Dependent Surveillance Broadcast], which is a technology where aircraft broadcast their position over a data link,a TASAR-equipped aircraft can receive and process the positions of other aircraft in the vicinity. The cockpit technology takes that data into account when computing optimum trajectory changes, to ensure those changes don’t interfere with the nearby traffic.
The benefit of doing that is when the pilot uses the tool’s recommendations for trajectory change optimizations, and when they make the request to air traffic control, these trajectory changes have already taken into account some of the surrounding traffic aircraft, and the air traffic controller is more likely to be able to approve the pilot’s request.
NTB: What's the main difference between TASAR and how pilots previously used to optimize their flight routes?
Wing: Pilots file a flight plan before the flight, and it’s approved by ATC [air traffic control], with perhaps an amendment by ATC. For the most part, pilots fly that flight path from beginning to end, without making changes. However, pilots occasionally have reason to optimize their flight along the way. They use the information they have available on hand, such as onboard weather data, the experience that the pilot has flying that route. Aircraft operators look for shortcuts they can make, but they don’t have a good source of information about traffic around them. They also don’t necessarily have up-to-date information about the wind field and some weather data.
The idea behind TASAR is to bring that data onboard and to put it into a software application that would be a full-time monitoring tool for trajectory optimization opportunities while the aircraft is en route. It will take into account what a pilot normally doesn’t have information for: traffic, the latest wind data, weather data, and turbulence data. This improves a pilot’s ability to optimize his flight more productive, and it makes their interactions with air traffic control (ATC) more productive, because they will be making requests that already account for ATC objectives like traffic separation. It’ll be a win-win for pilots and controllers.
NTB: How will it make flying more efficient?
Wing: Flights are planned based on the information known at the time of departure or before departure, but things change during the flight. Weather is a dynamic environment. The traffic is dynamic. Even the goals of a flight can change. For instance, pilots may first try to be as fuel-efficient as possible, and then determine based on changes during the flight that they need to get there as fast as possible, so the objective is changed. The idea of having a tool onboard the aircraft for the pilot to use can take that dynamic environment into account and helps the flight to better meet its goals throughout the flight.
NTB: How does it work? How does it find the most efficient route?
Wing: The software application runs on a portable device called an Electronic Flight Bag, or EFB. The Electronic Flight Bag is basically a tablet computer designed for cockpit use. More and more aircraft operators are getting benefits from electronic flight bags. The EFB would be connected to the aircraft avionics, and it only needs to be connected in a read-only mode, which is much cheaper and easier to get certification and operational approval. It would read information from the aircraft systems such as the current position and the route of flight from the flight management system; it will be able to stay up to date on the data all the time. It also would be connected to the ADS-B receiver, if the aircraft has one installed, and will be able to receive and incorporate, in real time, the traffic aircraft positions nearby. In fact, we developed the TASAR concept as a means for pilots or for aircraft operators to gain near-term benefits from equipping with ADS-B.
If you have a broadband Internet access in the aircraft, the software can connect to Internet sources that provide all kinds of useful and relevant information for ways to optimize the flight. An example of that might be connecting to the NOAA [National Oceanic and Atmospheric Administration] website to upload the latest wind forecast, which is currently updated on an hourly basis. We could see that update in real time, and use that information to help optimize the flight based on the very latest data.
NTB: How did the project come about?
Wing: I have been working in aircraft management for the last 15 years or so, and most of my research has been focused on studying advanced concepts of airborne separation. As part of that research, we developed an automation tool for the flight deck to enable aircraft to separate themselves from other traffic, and basically manage and optimize their own trajectory in an airspace that contains other aircraft that might be also self-separating or might be controlled from the ground by ATC.
So, for this self-separation research, we developed a very advanced, state-of-the-art conflict detection and resolution automation system that we have been using in research simulations over the last decade or so. For TASAR, we are leveraging that technology to create a tool that uses the same advanced functionality, but could be used under the current rules and procedures for pilots. Our goal is to make it available to the aircraft operator community in the near term, to help them gain operational benefits from equipping with ADS-B, and to gain benefits from this type of powerful optimization tool right in the cockpit.
NTB: What's next with it? Is TASAR in use? Is it in the testing phase?
Wing: We’ve accomplished a lot in the last year-and-a-half of the TASAR activity. We’ve developed the prototype software application, and we have done a preliminary analysis of user benefits, how aircraft operators benefit by having this technology onboard. We have done an analysis of safety and hazards and of certification requirements for getting this software approved and put on an aircraft. We have conducted a human in-loop simulation with airline pilots using the TASAR software in a high-fidelity flight simulator equipped with an Electronic Flight Bag.
Right now, we are conducting a flight trial out of the Newport News Williamsburg International Airport here at NASA Langley, to test the software on an actual aircraft. Last week and this week [This interview was conducted on Nov. 19, 2013.], we’ve been running flight trials in a Piaggio Avanti aircraft. It’s operated by Advanced Aerospace Solutions, LLC. We are bringing in airline pilots and other experienced aviators to help us test the software in flight.
Our next activity: We’re talking to airlines about having them potentially fly this technology on commercial flights, and we are also adding more information into the TASAR application software to help improve the optimization capabilities. We’re very excited about TASAR. There’s a lot of interest in the user community being expressed to NASA, and interest in putting TASAR technology on their aircraft in the near term.
NTB: What were the biggest technical challenges?
Wing: One of the challenges we’re working on is putting the software system onto the aircraft and connecting it to the avionics systems. We do that in order for the software to gather flight information in real time from the flight management system and other systems. The challenge is that those systems are not designed to share everything that we might need for a good optimization. We are looking into the details of what is available, and what compensations we might need to make in order to have this work in aircraft that are already flying today. Future avionics systems could be designed to share their data more directly and readily, and we certainly hope that will happen. Perhaps an application like this, which provides so many benefits to the operators, will spur that along.
Another one of the challenges, and it’s just a reality: Right now, there aren’t all that many aircraft flying around broadcasting their position over ADS-B. The FAA has established a mandate that by 2020 all aircraft will be required to broadcast their position over ADS-B wherever transponders are required. Nevertheless, in our flight trial, we are already seeing quite a number of aircraft in our vicinity that are broadcasting ADS-B. We have successfully, in this flight trial, been able to compute trajectory changes that save time and fuel and also take the traffic aircraft into account, and that have been requested to ATC and approved.
NTB: How is your team structured?
Wing: The TASAR activity is sponsored by the Concepts and Technology Development (CTD) Project of the NASA Airspace Systems Program. The NASA TASAR team consists of a just few civil servants at the present time. Most of the research and development for TASAR is being conducted under a set of contracts under the NASA Research Announcement (NRA). Engility Corporation is developing the TASAR software prototype application, and they are conducting the benefit analysis. They also are conducting flight trials under a sub-contract with Advanced Aerospace Solutions. Under a separate contract, Rockwell Collins is conducting the certification analysis, and also is conducting human in-loop simulations through a sub-contractor, the University of Iowa Operator Performance Lab.
To download this interview as a podcast, click here.