Charlottesville police have released pictures of a plastic device found during a Sept. 9 traffic stop that officers believed could have been a pipe bomb.
Police released the photos after Robert Jamal Pryor, 34, who is charged with possessing an explosive device, said that the object was actually an air pump.
Once the device was discovered, police called the department’s new bomb-sniffing dog to investigate; the dog alerted that the device could contain explosives. The investigation also led to road closures and a response from the Virginia State Police bomb squad.
“Based on the pipe-bomb design of the pressurized device, inaccurately characterized as an ‘air pump,’ and the circumstances surrounding the encounter, [city police] officers and [state police] responded appropriately by containing and then disrupting the device,” Tyler Hawn, city police spokesman, said in an email.
The email included photos of the device and a picture of the X-ray taken by state troopers before the device was submerged in water and broken up by a controlled explosion. The picture shows an oblong object created out of sections of polyvinyl chloride (PVC) plastic pipe connected by PVC adapters, sealed with purple solvent welding material commonly used in plumbing.
One end of the object has a metallic protrusion that, in the X-ray, appears to be a Schrader valve like those used in automobile and bicycle tires to allow compressed air to flow in and out.
The email also included photos and diagrams of homemade pipe bombs made with the exact same materials that appear to be similar to those used in the device.
An internet search shows a variety of do-it-yourself compressed air containers being built of the same materials with a Schrader valve used to fill the container, including instructions published by the University of Virginia School of Engineering and Applied Sciences.
The devices may be filled with air using a simple bicycle pump, according to the instructions.
The school instructions include connecting the device to a solenoid valve to use the compressed air in a container for a variety of uses, including stagecraft.
“There are nearly limitless applications of a small portable compressed air effect in theater,” the instructions state. “You can connect the outlet of the solenoid valve to a small piston and push an object forward. Another possibility is to screw the outlet into an open-ended PVC tube, creating [an] air cannon. Regardless of the end application, the PVC air tank is a flexible, useful piece of theater technology.”
Other online sources recommend against using such a homemade device for storing compressed air because of the possibility that the container could violently rupture under pressure.
Glues used in connecting the plastic pipe pieces include potentially explosive chemicals such as tetrahydrofuran, acetone, methyl ethyl ketone, cyclohexanone and fumed silica. Bomb dogs are trained to smell a variety of chemicals used in constructing bombs, including 2,4,6-trinitrotoluene (TNT), triacetone triperoxide (TATP) and other vapor plumes that explosive materials emit.
Remnants of the device are currently being analyzed by the state’s crime lab to determine if it was actually an explosive device. State law allows charging persons who possess devices that look like explosive devices even if the devices are inert.
Pryor is charged with possession of an explosive device, possession of marijuana, having an expired registration and not having a valid inspection sticker. He is slated for a 1 p.m. hearing in Charlottesville General District court on Nov. 7, at which time the evidence against him will be explained to a judge to determine if there is enough evidence of a crime to proceed with the case.