One of the “bottlenecks” in airplane construction is the driving of thousands of rivets, many of which must be installed in places accessible from only one side. Engineers say an all-metal pursuit plane has as many as 800 fastening points which can be reached on but onk side, while a big bomber may have 10,008, This fabrication bottleneck may be solve§ by the new explosive rivets developed by DuPont, rivets that explode with heat and"set themselves permanently. The whole operation is performed from one side with ease and speed, one man setting 15 to 20 rivets a minute after they have been placed. The rivet itself, weighing about one-fourth as much as the ordinary mechanical “blind” rivet, has a charge of high explosive in a cavity at the end of its shank. Once in place, an electric riveting gun weighing less than five pounds applies heat to the rivet head, and when it reaches 130 degrees Centigrade the charge explodes, expanding the shank and setting it firmly. The explosive charge can be regulated accurately to control the expansion to 20 thousandths inch.