FIFTY years ago today, the Soviet Union announced that it had shot down an American U-2 spy plane and that its pilot, Francis Gary Powers, was alive.It seems like a long-ago event from the cold war. That may be why, in this era of satellites and drones, most people are surprised to learn that the U-2 is not only still in use, but that it is as much a part of our national security structure as it was a half-century ago.

Every decade or so there is chatter about replacing the U-2. And yet, thanks to its remarkable technological and operational capacity and flexibility, the U-2 has in recent years been used to find homemade bombs in Afghanistan, drug lords in Colombia, mass graves in the former Yugoslavia and budding nuclear weapons programs in the Middle East. It has also been critical in non-military missions like measuring ozone levels and mapping disaster zones.

This time, though, it looks pretty certain that the Air Force will follow through on its plans to retire the U-2 as soon as it can field a Global Hawk drone retrofitted with electronic eavesdropping devices.

I flew the U-2 during the 1990s, and I received this news as if I had learned that an old friend was dying. It may seem odd to grieve for a machine. But the U-2 is no ordinary vehicle. Some in my world call flying the plane a religion, others a calling. For me it was a gift.

The U-2 is nicknamed the Dragon Lady for good reason. You never knew what to expect when you took it into the air, no matter how seasoned a pilot you were. This was an unfortunate consequence of its design. The trade-off of a plane built light enough to fly above 70,000 feet is that it is almost impossible to control. And 13 miles above the ground, the atmosphere is so thin that the “envelope” between stalling and “overspeed” — going so fast you lose control of the plane, resulting in an unrecoverable nose dive — is razor-thin, making minor disruptions, even turbulence, as deadly as a missile. The challenge is even greater near the ground, since to save weight, the plane doesn’t have normal landing gear.

As I was told before one of my tryout flights, “Landing the U-2 is a lot like playing pool. It’s not so much how you shoot as how you set up your shot.” Or, as my former wing commander said, “We’ve all had moments when we could just as easily have made one tiny move the other way and ended up dead.”

Getting the plane up and down was not the only challenge. Staying airborne — and alert — for countless hours, looking at nothing but sky, was another. I learned the hard way, for example, that you can get diaper rash from Gatorade.

Other risks were less benign, as I found when I was the ground officer for a pilot who radioed, “My skin feels like it’s crawling.” He had the bends so badly from changes in pressure that when he landed his body was covered with huge welts. Had the weather not cleared in time for him to land, these bubbles of nitrogen might have lodged in his brain or optical nerve — as they had in other U-2 pilots.

Were the risks worth it? Absolutely. The advantage of having a human being in the pilot’s seat of a reconnaissance plane is overwhelming. A person can troubleshoot problems in mid-flight, with creativity that a computer lacks and a proximity to the problem that a remote-control pilot can never achieve. A pilot also has unique situational awareness: I’ve been on more than one mission in which I was able to distinguish promising details that a drone would have missed.

It was worth it personally, too. I’ll never forget the adrenaline surge of landing what was basically a multimillion-dollar jet-powered glider on its 12-inch tail wheel from a full stall while wearing a space suit. And I’ll always remember the peace of sitting alone on the quiet edge of space, out of radio contact for hours.

The new generation of drones have their merits. But flying robots, no matter how advanced, can’t measure up to the courage and commitment of a pilot who is risking her life for the sake of the mission.

Reconnaissance will outlive the U-2, but there will always be a divot in the hearts of those who have seen the curvature of the earth, the stars seemingly close enough to touch, and known the satisfaction of having completed a mission with the Dragon Lady.