BRUNSWICK, Ohio USA — Investigators trying to determine what caused a Monday blast at the home of a Brunswick mail carrier now think an explosive substance found by bomb experts was used for the man's model rocket-building hobby.

Officers from the Southwest Enforcement Bureau Bomb Squad discovered a 3-pound coffee can containing black powder pellets in the Keller Hanna Drive home of Patrick C. Ralph. The search was conducted at the request of Brunswick police after the 39-year-old postal employee was injured in an explosion in his basement. Neighbors were evacuated from their homes for about one hour while SEB bomb unit officers searched the house for additional explosives.

A coffee can filled with black powder pellets and several 5- to 6-foot tall model rockets were found in the search. "He possibly was involved in improvising some type of rocket engine," said SEB Bomb Unit Capt. Wayne Schmigel. "There were no other explosives or bomb making parts there, but we found an extensive collection of rockets there, some taller than I am."

Investigators would not confirm that the black powder found in Ralph's basement caused the first explosion. "We don't know what detonated," Schmigel said. "That's the only substance we found, so I wouldn't call him a mad bomber or anything like that. All the evidence at the scene, in my opinion, indicates that it was a mishap."

"Brunswick Police are still investigating the cause of the blast. Ralph has not been charged. He is scheduled to be questioned today or Friday by Brunswick detectives," Sgt. Nick Solar said yesterday. Black powder pellets can be purchased legally by certain hobbyists, but many amateur rocketeers discourage its use as a fuel.

"You can buy it for use in sport shooting, and get a 50-pound exemption from the Bureau of Alcohol, Tobacco and Firearms, but you need a federal law explosion permit for anything else," said aerospace engineer John Wickman, spokesman for the High Plains Rocket Society in Casper, Wyoming. "Most builders use the same solid rocket propellant used in the space shuttle. It's a rubbery compound that is much more stable. If you light it, it burns like a candle.

"It doesn't take much to ignite black powder," Wickman said. "A spark will do, and when it's lit a tremendous amount of gas is released. It's a very high speed burn."

Ralph could not be reached for comment yesterday. He is currently in stable condition at MetroHealth Medical Center in Cleveland. A hospital spokeswoman said his left hand was seriously injured and he had cuts on one thigh.

U.S. Postal inspectors joined the investigation Monday when police learned Ralph is employed as a letter carrier at the Midpark post office in Middleburg Heights. He has been a postal service employee for 13 years. Cleveland Postal District Communications Specialist Mark Reynolds said Ralph is currently on paid medical leave while the postal inspectors conduct their own investigation of the incident.

"He is not suspended and there has been no disciplinary action at this time. "A range of things could happen from nothing to removal. A lot depends on his work history. All indications are that there are no red flags on his work record."

Copyright © 1999 Akron Beacon Journal.