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CARC supports C.A. Johnson high-altitude balloon project (photos and video)


The weather balloon launches from Chapin High School, on it’s way to 96,000 feet.

C.A. Johnson High School’s Air Force JROTC program instructor, Maj. Reginald Slade, uses words like “very determined” and “tenacious” to describe his teaching style. That attitude led him this semester to devise a plan for his students to launch a weather balloon to the edge of space.

“I wanted to do some kind of project to inspire them,” Slade said. “The legacy of our school warrants the project.”

Aerospace is a recurring theme at C.A. Johnson, which is located near downtown Columbia. Current NASA administrator Charles Bolden is a 1964 graduate of C.A. Johnson High School.

Slade’s predecessor is Col. Walter L. Watson, also a C.A. Johnson graduate, and the first and only African-American to fly the nation’s highest and fastest aircraft, the SR-71 “Blackbird,” a long-range “strategic reconnaissance aircraft,” capable of flying an estimated maximum altitude of around 85,000 feet.

On May 24, Slade’s weather balloon project would ascend higher than the SR-71. But to get there, he first needed an amateur radio operator. Working from a donated budget of around $1,000, Slade’s team pieced together all the parts they needed to send a weather balloon and a small payload to an estimated 80,000 feet.

Several weeks before the scheduled launch, Slade decided to add an APRS tracking system to the payload to complement the onboard GPS. APRS, short for automatic packet reporting system, is an amateur radio-based network used to share information on telemetry, such as position, weather information, etc. In the case of the weather balloon, using APRS would allow Slade and his team to track the location, altitude, speed, barometric pressure and temperature of their payload, using the aprs.fi website.

The balloon's flight computer.

The balloon’s flight computer.

But using the APRS network requires an amateur radio license, and with launch just two weeks away, he feared he wouldn’t be able to secure a Technician-class license and callsign in time for lift-off. He reached out to the Columbia Amateur Radio Club for help.

Club president, Andy Haworth, KK4DSD, met with Slade’s team a week before the launch to confirm the 250mW APRS system was beaconing packets. The system runs on four AA batteries and transmits a packet every minute through a half-wave wire dipole antenna on the 2-meter band.

On the morning of May 24, the C.A. Johnson team traveled to their launch site at Chapin High School and assembled their balloon. It was predicted to ascend to a burst altitude of 80,000 feet and land somewhere in Orangeburg County based on computer models plotted several days before.


Slade, with assistance from his students, inflates the weather balloon before launch.

Once in the air, the balloon showed up immediately on the APRS network using the callsign KK4DSD-11 (11 is the APRS designator for weather balloons).

It was in the air for more than five hours, tracking a course largely parallel to I-26, reaching more than 95,000 feet before bursting between lakes Moultrie and Marion near the eastern tip of Orangeburg County.

The descent took more than an hour and it sped eastward across the state, resting in a lightly wooded area in the Francis Marion State Forest, only about 20 miles from the Atlantic Ocean.

Slade recovered the payload several days later, along with hours of GoPro video. The data from the flight computer was intact and contained thousands of datapoints related to the balloon’s position, altitude and weather conditions. Slade said he will be using the launch and data in future classes.


The balloon's journey.

The balloon’s journey.

Haworth took the opportunity to talk about the value of ham radio with the students involved.

“I’ve always wanted to launch a balloon,” he said. “I told them I was living vicariously through them. I was honored to help.”

Slade said he intends to add an amateur radio station to his classroom with his remaining funds, and hopes his future students will consider getting their amateur license. He’s particularly excited at the prospect of listening for the International Space Station.

“There’s all kinds of ways I can leverage the experience,” he said.


Photo Gallery and Graphics

Photos by Andy, KK4DSD

Permanent link to this article: http://w4cae.com/carc-supports-c-a-johnson-high-altitude-balloon-project/

1 comment

  1. Reginald Slade


    This is an awesome article. Thank you for publishing and getting our students some well deserved publicity!

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