RWK May 31 2025 High-Altitude Balloon Launch Wrap-Up

By Chip Coker KD4C

The Richardson Area Balloonatics successfully launched (and mostly successfully recovered) another High-Altitude Balloon (HAB) on May 31 2025. Launch location was Gainesville TX and the landing/recovery location was Celeste TX (about 9 miles north of Farmersville TX). Highest Altitude was 120,042 Feet – an new RWK record (around 22 miles high, or one third of the way to space)!

We had around 60 people at the launch site, including at least 20 RWK members and several UTD students (some from their AIAA group) and a number of DCARA members. We even had a pilot ham (Greg KF5TU) that flew from McKinney to Gainesville and took the FBO courtesy shuttle to the launch site. On the ground he worked stations over the DMR repeater and attempted more DMR contacts on the return trip. Definitely one of the most interesting launch participants!

Launch preparations went mostly according to plan, with inflation of the balloon and assemblage of the launch tether and payload string. Joe W5MGY was in charge of balloon inflation, with handling/launch assistance from Travis KI5PGM and Ken N2VIP. Even though it was a hike to Gainesville, it was a beautiful day to launch and the weather couldn’t have been much better (light to no winds and clear skies). We had lots of help with the actual launch and many spectators were just along to see what it takes to launch a balloon.

After launch we quickly got into tracking the balloon and working the payloads from the launch location. We had an on-site tracking station with an AZ-EL rotator that was literally pointing to the balloon as it rose. The launch crew started packing the launch equipment and hung around for about 30 minutes after the launch while the balloon rose and started its travel southeast. And then it was time to chase!

For chase/recovery, I counted 8 vehicles and around 16 people (not including the group that drifted in from Greenville).

You can see the list of planned payloads on the launch announcement. Most of the payloads worked very well! We flew 3 different tracker payloads and the K5RWK Horus tracker performed excellently. The K5PRK and KE5GDB trackers lost GPS lock mid flight (thus no accurate position) but continued to operate through landing. The Wenet HD camera performed well and we received almost 200 images throughout the flight (including several of the camera sitting in the tree after landing!). The pictures were not as clear as the last launch due to a lot of atmospheric haze and smoke from the Canadian fires as well as a persistent camera focus issue with the HD camera.

The DMR Single-Frequency Repeater was again very popular and activity started almost immediately after launch and continued throughout the ascent. I haven’t (yet) calculated the total number of stations, but we heard several from the Houston area (JSC/Clear Lake, Pearland, Humble, Huntsville), and a couple from the Texarkana area (the Quad-states hamfest was going on), as well as lots from all around the North Texas area. I have the full DMR audio recording (with silence removed) and it is over 32 minutes of audio. It will be posted here soon.

The SSTV payload was a major success and we’ve gotten many reports of successful image reception from the downsampled HD cam images. Andrew was especially proud of his “90s WordArt” callsign.

We did have a few payload issues, which is to be expected. Doug’s “digi-talker” voice telemetry module worked from launch up through about 10,000 feet and then went silent – not sure just yet how it failed. The WSPR payload from K5UTD was never received and may have suffered an early antenna loss due to twisting. The new 360 cam suffered from a new “twist to start/stop record” feature that wasn’t discovered until it was too late, so we missed the spectacular footage of the balloon bursting like we had from the last launch.

I was particularly pleased by the number of tracking stations that were contributing to the amateur.sondehub.org tracking site. If you built a tracker, you can see where you were on the list of received packets. As expected, the satellite stations at K5UTD, KE5GDB, and KD4C and the tall receivers at W5NGU and N5COR did the best, but every packet contribution helps to complete a full launch-to-recovery dataset, even the ones from “NOCALL” and “CHANGEME”.

Recovery was definitely a challenge as the payload string landed in the top of a tree canopy (this is primarily why the launch location was changed at the last minute – to avoid trees – but the balloon found them anyway). We (actually it was Alice KI1TEN) spotted the parachute and Doug’s orange digitalker box right away, but then spent the next 2-1/2 hours trying to get it out of the trees.

Special thanks to Al KN5EEE and new RWK Member Jayson KJ5AXE for their persistent efforts to extract the payloads with a 35 foot extension pole and several improvised implements. We needed a good pole-mounted tree trimming saw to deal with a couple of very difficult branches! Alas, it seems that a sacrifice must be made to the balloon gods on each flight, and on this flight it was the UTD WSPR payload – location still TBD!

[recovery photo]

Again, thanks to Jeff KI5SDS whose family made a generous donation after the launch last fall to finance this one! These are expensive activities (the balloon and hydrogen alone cost between $500-600) and we appreciate the financial support.

We will have a special event QSL card available shortly if you received data/images from the balloon or made contact through the DMR repeater. We’ll also have a Worked All Payloads award for the certified radio freaks. Be sure to submit your entry for a QSL card and/or Worked All Payloads award (form below – entries will be closing soon).

HAB Launch on YouTube

Michael Porter was with us most of the day and covered the launch and recovery. He has a good view of the launch and overall event.

Paul K5VOP covered the tracking with a livestream. He had some early confusion so feel free to ship the first hour or so.

Apply for QSL Card or “Worked All Payloads” Award

After the launch, tell us all the ways that you interacted with the Balloon and possibly earn the prestigious “Worked All Payloads” award.