U.S. soldiers in Vietnam heard rumors of ghosts; the Viet Cong chalked it up to bad luck.
- By Roger Warner
- Air & Space magazine, May 2004
(Page 4 of 5)
The YO-3A had a 220-horsepower Continental engine mounted in the nose and an ordinary propeller shaft in the traditional location but driven at low rpm by quiet rubber belts. It had retractable landing gear mounted inboard on the wings. The observer sat in the front under a large bubble canopy and the pilot in the back. The engine compartment had several kinds of acoustic insulation and a muffler mounted on the starboard side of the fuselage. It had a brand-new sensor package, including a laser target designator that was not compatible with anything the military services had at the time. But what really set the YO-3A apart from its predecessor was that, at $11 million dollars, the program was big enough to trigger every kind of corporate and military oversight, procurement headache, and interservice backstabbing imaginable. “We could have done better,” says Stanley Hall, nominally in charge of airframe design, in reality a man whose design decisions were overruled by higher-ranking executives. The YO-3As were not only much heavier than the QT-2s (3,700 pounds versus 2,500 pounds) but also a lot noisier, with a quiet cruising altitude of 1,500 instead of 800 feet.
With U.S. forces already starting to withdraw from the war, and funding levels falling, only 11 YO-3As were built. Nine were sent to Vietnam in early 1970. They were flown and maintained by the Army in Hue Phu Bai (where a few Marines flew them too) and Long Thanh North, a big base east of Saigon. The little nocturnal spyplanes, nicknamed Yo-Yos, no longer enjoyed an advocate as high up the command ladder as Westmoreland, who was long gone. There was no effort to see what airborne stealth reconnaissance could achieve if given the right resources. And yet the Yo-Yos did their job well.
Much credit goes to the sensor package, which had leapfrogged several generations of technology from the QT-2’s primitive night vision scopes. Never mind the laser target designator, which didn’t work reliably and was seldom used. Protruding from the fuselage beneath the front seat was an ocular, or eyeball. It was like a periscope but controlled by a joystick, and gimballed, so that the horizon always looked horizontal in the viewer. Equipped with a light amplifier for night vision, along with an infrared viewer that sensed heat, it provided a view as clear as daytime of the nighttime scene below. The infrared viewer moved in tandem with an infrared illuminator, a kind of searchlight mounted in the belly, aft of the other optics.
Mark Kizaric was a YO-3A observer. A few months out of high school and a self-described pimple-faced kid, he became adept at using the ocular and manipulating the joystick. “After a while you’d get in a zone where you didn’t even think of yourself as being up in an aircraft,” he recalls. “You kinda lost contact with the real world. It was more like a video game. You’re just, you know, going along, you’re acquiring targets, noting positions, calling in artillery.
“Most of the time we worked with artillery,” says Kizaric, who is now an engineer in Wisconsin. “One especially strong memory is of a very large sampan moving down a river, 30 to 40 feet in length and riding very low in the water at about three or four o’clock in the morning where nobody’s supposed to be. We directed artillery fire, and though I’ll acknowledge a level of skill on my part, [there was] also an awful lot of luck. I happened to get a direct artillery hit. The sampan had to be loaded from stem to stern with ammunition, because there was a blinding flash that, even outside the ocular, lit up the whole night sky. I lifted my head away and there was this brilliant orange flash. A few seconds later I put my eye back in the ocular and the sampan had literally vanished.”
On other nights and missions, the Yo-Yos worked with the helicopter gunships of the 1st Air Cavalry. “We would go well ahead of the choppers and acquire the targets, because we were silent,” says Kizaric. “We would find, you know, people sitting around campfires, hot truck exhaust, something like that. We could literally see, in some cases, people moving around on the ground. We would note the position, call in the Cobra gunships, and lock onto the target with our ocular and illuminate the target. When people on the ground heard the choppers come in, all the fires go out and they start scrambling. But it was too late then. We had them on the IRI—the infrared illuminator. The gunships had a screen that could also pick up the infrared illuminator, and so they would home in and open fire.
“[The YO-3] was a wonderful aircraft, when it worked,” Kizaric says. Unfortunately, the Yo-Yos didn’t always work. Fuel management glitches led to a few crash landings; one unexplained crash killed the pilot and observer. Though Lockheed fixed some of the fuel problems, morale dropped at the Long Thanh North base, and with it the number of flights per week. The Army discontinued the Yo-Yo flights in August 1971, and the military’s quiet spyplane program ended five years and many evolutionary changes after it began.
How stealthy were the quiet planes? Where they flew, enemy radar was rare. They were seen by the enemy from time to time, usually when the aircraft made silhouettes against cloud layers backlit by a full moon. On moonless nights, the little planes were functionally invisible as well as practically inaudible. None of the unarmed spyplanes was ever shot down, and on a few occasions, the pilots flew less then a hundred feet above and beside enemy truck convoys at night, just to see if they could get away with it. They did.