A highly experienced Honeywell veteran is leaving the company after more than three decades traveling across the country and around the world on our behalf. Well, “being retired” may be more accurate since we’re really talking about the venerable Sabre 65—originally designed for the U.S. Air Force in the 1950s by North American Aviation and then developed as a mid-sized business jet. The so-called “Mark V” swept-back wing was combined with TFE731 turbofan engines to create the Series 65. As we’ll see, this particular aircraft has played a critical role in the development of Honeywell products that improve both the safety and efficiency of flight, especially collision avoidance. The Sabre was one of six purchased in the early 1980s, replacing AlliedSignal’s Falcon 20s and Aero Commander Westwinds. It originally was based in Morristown, N.J., and used for corporate transportation and later transferred to Allied’s Olathe, Kan., facility in 1985, one of many moves. After AlliedSignal merged with Honeywell in 1999, keeping the Honeywell name, the aircraft was transferred to Honeywell’s Deer Valley Airport (DVT) facility in Phoenix. For various reasons, the Sabreliner did not receive a very warm welcome in the sweltering heat of Deer Valley and was soon nicknamed the “Laborliner.” According to one pilot familiar with DVT, the combination of the Sabre’s swept wing design, Phoenix’s infamous hot weather and DVT’s runways designed for general aviation aircraft, meant that getting the Sabre up into the wild blue yonder was not always a labor of love. “Runway performance was another story,” Markus Johnson, retired Chief Pilot, Flight Test Operations at Everett, Wash., says. “It was built on the foundation of a fighter, and in a lot of ways, it flew like one. It was indeed the sweetest flying machine—once you got it up to 200 knots or so.” After a few years, the aircraft was relocated to the flight test operation at Paine Field in Everett, and later transferred back to Arizona to reside at the Phoenix Sky Harbor flight test operation. But if simply carting around executives was its main mission, the Sabre just would be another check mark in a corporate aviation inventory. No, this particular Sabre was the first jet aircraft to have TCAS and a Mode S transponder installed—an equipage that would lead to an uncomfortable encounter in U.K. airspace. Of course, nowadays we’re all pretty familiar with the life-saving Traffic Alert and Collision Avoidance System and its Mode S transponder that warns pilots of the presence of other transponder-equipped aircraft which may present a threat of mid-air collision. But, although Honeywell’s research into collision avoidance systems had been ongoing since the mid-1950s, the first TCAS manufacturing authorization (awarded to Bendix/King) didn’t happen until 1990. So, on Feb. 23, 1989, when Tommy Littlejohn, Bill Callan and Steve Kilbourne started out on a 31-day around-the-world TCAS demo tour for various airlines, the concept was still pretty new. They had added a Litton LTN 92 inertial navigation system in the cabin that Callan operated for overwater operations. As Kilbourne tells it, they were flying from Iceland to England using their Mode S transponders, sending out, or “squawking” in pilot lingo, aircraft altitude and identity info. As they arrived in U.K. airspace they noticed two high-speed targets on their radar screen rapidly coming up behind them. About that time we got a call from Air Traffic Control asking if we were squawking “mode sierra.” We replied that, as a matter of fact, we were. ATC then asked us in a stern voice to stop squawking mode sierra until we left Her Majesty’s Airspace. It turns out that the U.K. ATC had never seen Mode S before and didn’t like the way it looked on their screens. The two high-speed targets that came up behind us were interceptors. So it was back to mode C transponders. A few days later they were going to fly over the Persian Gulf, not long after the USS Vincennes guided missile cruiser shot down an Iran Air flight because of mistaken identity. “We actually removed the Mode S boxes from the racks before takeoff … just in case,” Kilbourne says. Somehow, they managed a month “on the road” with only one Com failure. Nevertheless, Kilbourne notes that “the lav was loaded to the ceiling with spares” —which led to another term pilots used for using the aircraft on long test runs: “Sabre-bladder.” The Sabre went on to help test many other programs including Honeywell’s Enhanced Ground Proximity Warning System (EGPWS), transponders and terrain-following radar altimeter navigation, to name a few. In addition to numerous EGPWS and TCAS tests (circling the world twice), the Sabre can claim: The first FAA certification of Runway Awareness and Advisory System (RAAS) in a bizjet The first installed Electronic Flight Information System (EFIS 10, brainchild of the late famous Sundstrand engineer Ace Card) One of the first airplanes to have synthetic vision installed. The Sabreliner remained at Sky Harbor until recently being sold. However, this particular aircraft’s legacy lives on in the hearts and minds of those who flew it, knowing it contributed on a grand scale to aviation safety and the saving of countless lives.