With runway safety incidents on the rise, Honeywell Aerospace is preparing to introduce Surf-A, a runway surface alert system that will provide a “third set of eyes” for pilots. Honeywell last week demonstrated the Surf-A system in a series of flights between Seattle and Yakima, Washington, using its Boeing 757 testbed. If all goes according to plan, Surf-A could be FAA certified and available for retrofit in the next 12 to 18 months.
Surf-A directly alerts pilots onboard the aircraft to the risk of runway incursions, excursions, or other wrong-surface events. The software uses GPS and ADS-B data in the runway engagement zone to monitor traffic and provides an aural alert to the pilot when its algorithms determine that the airplane is on a trajectory that could result in a collision in the next 30 seconds.
Pilots using the Surf-A software can hear four different alerts: “traffic on final,” “traffic behind,” “traffic on runway,” and “traffic intersecting runway.” In addition to the aural alerts, text messages also appear on the pilot’s navigation display.
“The pilot is the ultimate decision-maker on what to do with this information,” Thea Feyereisen, a senior technical fellow at Honeywell Aerospace who is helping to develop the Surf-A system, told reporters during a briefing at Boeing Field in Seattle last week. “Just as if your copilot had said, ‘Hey, there's someone on the runway,’ this is a third pair of eyes for the pilot.”
Surf-A builds upon Honeywell’s already-certified runway awareness and advisory system and SmartRunway/SmartLanding software, which use the aircraft’s GPS location combined with geographical data to provide onboard alerts when a pilot is at risk of a runway overrun or wrong-surface landing. SmartRunway and SmartLanding can also alert pilots when takeoff flaps are not set, an approach is unstable, or if a runway is too short, for example.
The next evolution of this Honeywell technology is Surf-IA (Situational Awareness on the Airport Surface with Indications and Alerts), which adds more sophisticated visual indicators to the flight displays. Honeywell has been testing this since 2018 in collaboration with Airbus and Dassault.
Whereas Surf-IA is intended for forward fit on new aircraft, the more basic Surf-A system will be available as a retrofit that is affordable and simple to install, Feyereisen explained. “It's our desire to get this not just as a forward-fit option but retrofit, and to get this capability to all levels of capable aircraft.”
After a spate of incidents involving near-misses at airports in the U.S. in the last year, the National Transportation Safety Board (NTSB) has once again called on the FAA to develop a system that alerts flight crews to the risk of a runway incursion.
On June 20, the agency issued investigative reports on two high-profile incidents involving runway incursions at Austin Bergstrom International Airport in Texas and John F. Kennedy International Airport in New York. In those reports, the agency reiterated its recommendation that the FAA collaborate with aircraft and avionics manufacturers to devise an onboard safety alert system.
The same week the NTSB issued those reports, Honeywell Aerospace coincidentally began a three-week-long flight demonstration tour to show a system under development that does exactly what the NTSB requested.
Called Surf-A, Honeywell’s runway surface alert system provides a “third set of eyes” for pilots, Thea Feyereisen, a senior technical fellow at Honeywell Aerospace, told reporters during a flight demonstration at Boeing Field in Seattle.
Honeywell Aerospace has been flight-testing the Surf-A software on a modified Boeing 757 test aircraft, which the team flew around the U.S. and Europe in June to demonstrate the technology to airline officials and other stakeholders. If all goes according to plan, Surf-A could gain FAA certification and availability for retrofit in the next 12 to 18 months.
Surf-A issues aural alerts and optional text warnings on the navigation display to warn pilots of potential runway incursions, excursions, or other wrong-surface events, such as taking off or landing on a taxiway. The software uses GPS and ADS-B data in the runway engagement zone to monitor traffic and provides an aural alert to the pilot when its algorithms determine that the airplane is on a trajectory that could result in a collision in the next 30 seconds.
Increasingly Close Calls
This year has already seen a staggering number of runway incursions. In the first quarter of 2024, the FAA counted 451 runway incursion events, up from 367 during that quarter of 2023.
According to the FAA’s runway safety statistics, about 1,700 runway incursions get reported in the U.S. every year. Roughly two-thirds of them resulted from pilot deviations while air traffic control issues and wayward ground vehicles account for the rest.
The most recent collision on U.S. soil happened in October 2023 at William P. Hobby Airport (KHOU) in Houston, where a Raytheon Hawker 850 attempted to take off and clipped the tail of a Cessna Mustang that approached an intersecting runway to land. Officials reported no injuries, but both jets sustained heavy damage. An NTSB investigation found that the crew of the Hawker business jet did not follow ATC instructions to line up and wait.
While collisions remain rare, close calls in similar situations have become increasingly common. In many cases, those close calls are merely seconds away from a potentially catastrophic accident. By giving pilots earlier notice of a potential collision, Surf-A could save a lot of lives, according to Feyereisen.
On January 2, five people died in a crash at Tokyo Haneda Airport when an Airbus A350 operated by Japan Airlines landed on the same runway where a Japan Coast Guard de Havilland Dash 8 waited to take off. Investigators determined that the Coast Guard aircraft entered the runway without clearance from ATC 40 seconds before the collision. Had the A350 been equipped with Surf-A, the crew would have heard a “traffic on runway” warning in time to execute a go-around.
Although the control towers at Haneda Airport were equipped with a runway collision detection system, ATC failed to notice that the Dash 8 had entered the runway, according to Feyereisen. “There was a flashing red light on the top of the monitor, and nobody was looking at that display,” she said. “Just like on the flight deck, it’s an integration challenge.”
In a subsequent close call in April at JFK, a Swiss Air Airbus A330 received ATC clearance to take off while ATC cleared four other jetliners to cross the same runway. The A330 crew rejected their takeoff clearance when they saw other aircraft crossing the runway.
That incident followed another close call at JFK in January 2023, when distracted pilots in an American Airlines 777-200 missed a turn while taxiing and crossed a runway without ATC clearance, putting them in the path of a Delta Air Lines 737-900ER on its takeoff roll. Airport surveillance detection equipment (ASDE-X) alerted the control tower of a potential collision, and controllers promptly canceled the 737’s takeoff clearance.
If the aircraft had been equipped with Surf-A, the pilots would have received the Honeywell alert 14 seconds before they received the alert from air traffic control, Feyereisen said.
During the April 17 incursion, the ASDE-X system at JFK did not issue an alert to ATC because the Swiss Air A330 “never reached the thresholds of both acceleration and velocity that would indicate to the system that the jetliner was in a ‘departure state,’” the NTSB determined. Surf-A would have audibly alerted the pilot of the A330 of traffic on the runway once the takeoff roll reached an acceleration of 4 knots per second.
The Surf-A system also provides optional situational awareness messages that appear in green on the display but do not issue aural alerts. So, even before commencing the takeoff roll, the A330 crew would have gotten notified about the incursion.
While ASDE-X has proven its worth on multiple occasions, the system has flaws—most notably its susceptibility to human error among air traffic controllers, Feyereisen explained. “They have to hear the alert. They have to cognitively process the alert. They have to then spit out the right instructions,” she said. “ASDE-X adds additional potential for human error and it adds additional delay.” Furthermore, ASDE-X's high cost has limited installation at only 35 of the busiest airports in the U.S. since its inception in 2003.
The Evolution of Runway Surface Alerts
Surf-A builds upon Honeywell’s already-certified runway awareness and advisory system and SmartRunway/SmartLanding software, which use the aircraft’s GPS location combined with geographical data to provide onboard alerts when a pilot runs a risk of a runway overrun or wrong-surface landing. SmartRunway and SmartLanding can also alert pilots when takeoff flaps are not set, an approach is unstable, or if a runway is too short, for example.
The SmartRunway/SmartLanding technology available today enhances the pilot’s awareness of their own aircraft and ground features, and Surf-A aids the technology by incorporating real-time runway traffic from ADS-B equipment.
The next evolution of the Honeywell technology—Surf-IA (Situational Awareness on the Airport Surface with Indications and Alerts)—adds more sophisticated visual indicators to the flight displays. Honeywell has been testing the system since 2018 in collaboration with Airbus and Dassault.
Whereas developers intended Surf-IA for forward fit on new aircraft, the more basic Surf-A system can serve as a retrofit that is affordable and simple to install, Feyereisen explained. “It's our desire to get this not just as a forward-fit option but retrofit, and to get this capability to all levels of capable aircraft,” she said.