Amateur rocketeers ready Miss September for launch

By CLARE KENNEDY, Owatonna People's Press

DODGE CENTER, Minn. (AP) - Craig Nelson's weekend hobby turns one well-worn cliche on its head. In this case, it is rocket science.

Nelson is a member of Tripoli, a group of amateur rocket builders who will be shooting off a 27-foot-long rocket named Miss September in just a few weeks.

On Sept. 25 the rocket could be flying high over the wastelands of Nevada. Or it could flame out entirely. There will be no dress rehearsal for Miss September when she launches in the Black Rock Desert.

"We have a lot of experience, and we also have a lot of computer simulation software that we can use to get our center of pressure and gravity to where we think it should be," Nelson said. "But to tell you the truth, with everything involved, you have maybe a 50-50 chance. One thing can go wrong and it can be catastrophic."

The element of uncertainty is one of the most addictive aspects of the sport, he said. Nelson can still vividly recall his first launch.

"It's exciting. It's a rush at minimum," Nelson said. "It blows a big hole in the ground and shoots out 20 feet of flame."

The sound of such an explosion is unlike any other, he said, struggling to describe it adequately.

"I was really surprised by the thrust and the sound of that motor when it takes off. It's sometimes like a boom, and others like a scream," Nelson said. "A few launches ago, we sent up a smaller four-pound rocket that broke the sound barrier 25 feet off the pad. Everybody's hats flew off. That's the fun part."

Needless to say, Miss September was not made from a kit. The men built Miss September from scratch, based on plans and specs for the WAC Corporal, a rocket design that dates to 1946. The rocket was originally used as a sounding device by the military - mostly to take atmospheric readings, Nelson said.

It's one of the largest and most complex ventures that the club has attempted to date. Its nearest rival is a rocket the club built two years ago, which was about half the size. Miss September required an ample amount of time, hard work and money.

"You're talking thousands of man hours. I would say we've been working on it - using eight guys on Saturdays - for about a year and half," Nelson said.

The men built all the parts - the metal casing, the motors, the fins - themselves.

"We have engineers and machinists in the group, so they did most of it. Whatever we can't machine we send to professionals," Nelson said.

One man in the club is even concocting the fuel cell, made of ammonium perchlorate, said David Donovan, a prefect for the club.

"For something this size, you have to make your own fuel. You can't buy a motor with 1,500 pounds of thrust at Wal-Mart," Donovan said. "If it burns too quick it could over-pressurize the motor casing and then it will explode. You want a controlled burn."

Once completed, the rocket will have six on board computers to regulate the various stages of its flight - a battery of barometric monitors and inertia sensors, which will regulate ignition and the final deployment of the parachutes.

The hobby does not come cheap, however. On this particular venture, the group has spent "$20,000 for 60 seconds of fun," Nelson said.

If successful, Miss September will reach a maximum height of eight miles, about 40,000 feet, and a speed of Mach 1.4 - about 600 miles per hour. (Its launch requires an altitude waiver from federal regulators, Nelson said.)

"Hopefully she will fly true," Donovan said.

Tripoli is an international organization, which is broken down into smaller chapters called "prefectures." Southern Minnesota's prefecture started up in 1999. It has about 25 members, spread over Minnesota, North Dakota, South Dakota, Wisconsin, and Iowa.

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Information from: Owatonna People's Press

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