In late 1964, Lockheed tried out a novel photographic reconnaissance rocket which they called "Ping-Pong". It had a rocket motor at each end and after reaching an interesting target a few miles away, would take photos through a centrally mounted camera, then fire another rocket in the nose to return to the launch area, where the pictures could be processed and analysed. It was fired out of an inclined tube, about 4 inches in diameter, and cleverly used a sliding fin unit, which on launch, the rocket collected at the top of the tube. When the return motor fired, the fins slid back to the "front" for stability on the second part of the trajectory. The trials conducted at Rosamund Dry Lake, California, were of a prototype system, but little was heard of PING-PONG after those tests.