The air force has decided the end has come for the venerable Dornier Do-28 surveillance aircraft after rust was discovered in their frames, military sources said. The German-made, fixed-landing-gear aircraft was the last canvas-covered plane in the air force's inventory and has seen nearly four decades of service. The Defense Ministry is expected to put them up for sale as surplus shortly. For years, the aircraft, dubbed "Agur" or crane, served as a platform for human surveillance. It had mounted binoculars behind the two pilots where a third crewman would scour the countryside to gather intelligence. It was heavily used during the first intifada to monitor Palestinian riots. But its main role was for airborne reconnaissance where it would locate targets and direct fighter jets or ground forces to them. It was heavily used in the 1973 Yom Kippur War and 1982 Lebanon War. The top-wing aircraft were one of the cheapest to maintain and operate in the IAF's inventory. It was equipped later with optic and thermal cameras, but gradually, its role was usurped by the unmanned aerial vehicles (UAVs) which were able to do the same job for longer hours and at less cost. "The Agur was a very primitive surveillance platform, very cheap to operate, and we used it till the last minute," said a senior IAF officer. Still, it was recently determined that the UAVs with their sophisticated but highly focused cameras couldn't provide the simple serendipity of wandering human eyes in flight. The slogan of the Agur squadron was "It's best what you see with your own eyes." The air force has decided continue with this tradition and has outfitted a number of its small Bonanzas, known as "Hofit," to continue with human surveillance. West Germany donated the Dornier Do-28 surveillance aircraft in 1971 and they were promptly renamed "Agur" and deployed in the 100th "Flying Camel" squadron based at Sde Dov north of Tel Aviv. The sight of the Agurs lined up on the tarmac, tilted back on their tail wheel, always brought to mind the heyday of propeller flight. According to The Middle East Military Balance, the air force has 15 Dornier Do-28s. For years, the twin-engine aircraft performed its task in relative obscurity. "I don't know if the public knew about our exploits," said Lior Couriel, who flew air reconnaissance missions with the Agur for nearly two decades. "We were intelligence and the less known the better." Couriel described the aircraft as "an old friend." "It had all the characteristics required for reconnaissance. It was slow and could fly for long periods," said Couriel, 46, who spent many hours on operational missions. "It was very stable and you couldn't shake it up." The aircraft saw missions in the Sinai, Jordan and Syria. Squadron logbooks record numerous cross-border penetration missions. One of its most famous pilots was former chief of General Staff Lt.-Gen. Rafael Eitan, who would fly operational missions as a reserve major after he retired from service. The Agur infamously came to the public's attention in 1990 when a reserve pilot stole one of them one night and took it for a joy ride around the country and then disappeared. The pilot first flew low over his parents' home in north Tel Aviv, buzzed the then chief of General Staff Lt.-Gen. Dan Shomron, and then disappeared. A week later the mystery ended when troops came upon the twisted wreckage of the Dornier on a mountain slope near Ma'aleh Gamla in the Golan Heights, the body of the pilot still inside. The pilot, 33-year-old Lt. (res.) Haggai Mori, did not leave any note behind, but it was assumed to have been a suicide.