ABOARD A HONEYWELL TEST PLANE — Aerospace giant Honeywell is building new cockpit alerts that developers say will give airline pilots more precious time to react to hazards at airports.

Honeywell senior test pilot Capt. Kirk Vining late last month put the alerts — called Surface Alert, or SURF-A — to the test by recreating some of the most serious near disasters at airports in recent aviation history.

Moments before landing at Topeka Regional Airport, a Gulfstream G550 business jet was stopped on the same runway where Vining was about to touch down at the Kansas airport.

“Traffic on runway!” called out the automated alert in the cockpit of Honeywell’s test plane: a 43-year-old Boeing 757, as Vining pulled up, aborted his landing and flew around the airport safely.

A host of serious close calls in recent years has raised concerns about how to better avoid them in ever-more congested airports. The National Transportation Safety Board and other safety experts have urged more advanced cockpit alerts like the ones Honeywell is testing.

Runway incursions, when a plane, person or vehicle is on the runway when they shouldn’t be, averaged 4.5 a day last year. The Federal Aviation Administration categorizes them by severity, where the top and rarest two are: “a serious incident in which a collision was narrowly avoided” followed by “an incident in which separation decreases and there is a significant potential for collision may result in a time-critical corrective/evasive response to avoid a collision.”

Serious runway incursions at U.S. airports peaked at 22 in 2023, the most in at least a decade. The FAA has added new lighting and other safety technology at airports around the country to try to get to its goal of zero close calls.

“He’s very good at being a bad pilot,” Thea Feyereisen, a distinguished technical fellow for Honeywell Aerospace Technologies, said of Vining. Her unit develops new cockpit features for aviators, and she said she expects the new suite to win regulator certification next year.

“Seconds count when you’re operating near the runway, and the sooner you can let the pilots know of a potential serious situation, the better,” Feyereisen said.

The Honeywell test plane wasn’t configured like a regular passenger jet, and there weren’t any paying customers on board. It had a set of roomy seats toward the front of the plane, but in the back, Honeywell flight engineers were positioned at consoles, monitoring flight data and the alerts in real time. Earlier that day, Honeywell demonstrated the technology on a flight with Department of Transportation, FAA and NTSB officials on board, a company spokesman told CNBC.

Vining performed a simulation of another incident from 2023, when an American Airlines 777 bound for London crossed a runway where a Delta Air Lines 737 was taking off instead of holding short of the runway as an air traffic controller instructed. The Delta pilot in that situation aborted takeoff and both planes landed safely at their destinations.

Honeywell said its SURF-A alerts could have given the pilots 10 additional seconds of reaction time with a potential collision notice. The new program Honeywell is testing uses Automatic Dependent Surveillance – Broadcast, or ADS-B data, a GPS for an airplane.

“It’s usually a very good working environment between pilots, air traffic control, airport management,” Vining said. “We get it done safely, efficiently and smoothly. But you could also see just the slightest interruption, a little variation, and things can go wrong very quickly.”

The aerospace giant already offers another suite of alerts that tells pilots if they’re about to make a mistake like landing or taking off on a taxiway instead of a runway, for example, with visual alerts on a screen as well as aural warnings — “Caution! Taxiway!” The so-called Smart X package also alerts pilots if flaps are not set correctly, if the runway is too short, or if they are coming in too high or too fast, among other situations.

“As aircraft get closer to the airports where there are other airplanes that are also flying low to the ground, attempting to land, that’s the most dangerous spot to have a collision occur,” said Jeff Guzzetti, a retired air safety investigator with the NTSB and the FAA. 

Those alerts have been on Alaska Airlines planes for years and, more recently, Southwest Airlines has added them. Honeywell said the alerts are currently flying on more than 3,000 planes operated by 20 airlines, but that’s still limited adoption with hundreds of carriers operating worldwide.

“Since we’ve implemented the software, I can’t think of an instance where we’ve had a runway incursion,” said Dave Hunt, Southwest’s vice president of safety and security and a 737 pilot.

American Airlines was also training its pilots on those alerts in the second quarter of the year, according to a lesson plan that was seen by CNBC. Last month, American received its first aircraft with the runway awareness and other alerts on board, a spokeswoman said, adding that its Boeing 737 pilots have now been trained on the tools.

The alerts aren’t required by regulators, but the FAA said it is “reviewing recommendations” from the Runway Safety Alerting Subgroup “to determine next steps,” referring to a group of airline, aerospace, pilot union, government and industry officials that last year recommended new planes include more advanced cockpit alerts in case of situational awareness issues at airports.

“The alerts occur further away from the runway so that if there’s an aircraft on the runway, you’re not having to make that decision very low to the ground,” said Jon Sites, director of flight operations safety at Alaska Airlines.

The United States is the busiest aviation market in the world, with 44,000 flights, carrying 3 million travelers a day. Serious aviation accidents are rare, and fatal crashes are rarer still.

But a nearly 16-year streak without a fatal incident was broken on Jan. 29 when an Army Black Hawk helicopter collided into an American Airlines regional jet that was moments away from landing at Washington Reagan National Airport, killing the 67 people aboard the two aircraft and raising concerns about congested U.S. airspace to a fever pitch. 

The aviation industry relies on a so-called Swiss cheese safety model, where each slice provides protection but comes with holes that are ideally covered when safety measures are stacked on top of one another.

“Aviation is built on layers of safety upon layers,” said Sites at Alaska Airlines.

Honeywell’s demonstration flight last month from Charles B. Wheeler Downtown Airport in Kansas City, Missouri, recreated a real incident that took place on a foggy morning in February 2023 in Austin, Texas, when a FedEx Boeing 767 plane aborted landing seconds before touching down on the same runway from which an air traffic controller cleared a Southwest 737 to take off.

The FedEx pilot had seen the outline of the Southwest plane through the fog and pulled up and later landed safely. Both flights continued to their destinations safely, but the two aircraft had gotten as close as 150 feet apart, less than the length of the FedEx 767, according to federal safety investigators.

Feyereisen said Honeywell’s technology could have provided the FedEx pilots in the 2023 Austin incident 28 seconds of advanced notice of traffic on the runway, when they only had a few moments to react, according to a report from the NTSB.

Feyereisen said the new technology could be retrofitted on older aircraft and is available for new jets.

“In general, the software costs tens of thousands of dollars [per plane], but not hundreds of thousands of dollars,” Feyereisen said. “So if you’re looking at [a] $150 million aircraft … it is less than a half a penny per passenger cost to the operation.”

Southwest this year added the software to its fleet of about 800 Boeing 737s. It cost between $20 million and $30 million to outfit the planes, Hunt said.

“It is cheaper than an accident,” he said.

On Feb. 25, a Southwest plane aborted its arrival after it was cleared to land at Chicago Midway International Airport when a Bombardier Challenger 350 business jet advanced onto its runway, with the Southwest jet passing less than 200 feet between the aircraft, before safely landing after a go-around, according to the NTSB.

Such close calls “are very, very rare, but obviously they’re something that are concerning and that we would try to mitigate as much as possible,” said Hunt. The Honeywell software is “very effective at ensuring our pilots are aware of where they are on the airport” and “does a really good job of preventing inadvertent runway incursions while taxiing,” he added.

When developing the warnings, Feyereisen said it’s key not to overwhelm pilots with too much information, known as “nuisance alerts,” which could end up being a distraction from critical safety tasks rather than a help.

“If you’re blasting alerts through a cockpit speaker at low altitudes during a critical phase of flight, such as approach to landing or takeoff, where pilots’ attention needs to be fully focused … you create too many distractions,” Southwest’s Hunt said.

There are also limitations to the existing alerts and the new programs Honeywell is testing. To avoid in-air collisions, commercial aircraft are required to have what’s called the Traffic Alert and Collision Avoidance System, or TCAS, which helps them see traffic around them in displays in the cockpit. But that system is generally used for altitudes of at least 1,000 feet.

That would not have necessarily helped the pilots on the American Airlines plane that was below 400 feet in the fatal collision with the Black Hawk helicopter in January in Washington, D.C.

“We are exploring alternatives to close that gap where you kind of can merge TCAS and ADS-B-type information together,” Feyereisen said. 

Sites, the safety director at Alaska, said the D.C. crash was “a huge, unexpected event in the industry, but it’s just, I think, our track record through the last 50 years shows that this is a very, very rare event.”

“That’s why we continue as an industry to try to find even better technology out there and enhancements to the current technology to keep this from ever happening and take the probability down to as low a level as possible,” he said. “I don’t know if in any aviation system you’ll ever get to zero, but I mean, we’re going to try to get as close to zero probability as we can.”

— CNBC’s Erin Black contributed to this report.