RWK Radio Balloon Launch Wrap-Up – Saturday 9/21

Update: The Balloon Launch is a wrap!

We had a great crew of at least 46 people at the Aubrey Middle School launch site.

The balloon was launched at 9:38am and reached a peak altitude of 111,315 feet (!)

Josh N4NZ captured drone video of the launch:

We had some spectacular images from the HD video camera. They are all available for viewing (for a couple of days) at ssdv.habhub.org and we will have the entire archive available soon. Here’s the first HD image after launch:

Here’s an image taken from 110,300 feet (take that, flat-earthers!):

Unfortunately the SSTV transmitter got stuck on the first image (still on the ground). The SSTV transmitter continued to transmit (with a voice announcement of altitude) and we had lots of successful decodes but the image never incremented.

The balloon made it to 111,315 feet before it popped, which is way over what was expected (we would have been very happy with 100,000 feet). Here is a still photo from the 360cam of the moment of burst. You can see the shreds of latex and what appears to be a gas bubble that hasn’t dissipated yet.

Here’s the balloon burst moment from the toy platform

The balloon was recovered at 12:58pm just northwest of Celina. Most of the 8 payloads were recovered. It appears that two payloads were lost post burst (one was subsequently recovered after analyzing the 360cam burst footage and following the payload down as it landed about 50 yards from the main balloon string). The payloads were significantly twisted and tangled after the balloon popped, causing a very rapid descent (initially 10,000 ft/min) and likely ground impact at 35mph, but it looks like all the recovered payloads survived.

The balloon path was very similar to the predictions, but the landing was significantly west of Celina given the extra altitude (111,315 feet!) and the fast descent rate (the balloon was expected to decend for about an hour but actually dropped in around 15 minutes due to tangling – initial descent rate was ~10,000 ft/min! and didn’t slow significantly). Here is the actual trajectory (you can compare with the prediction below):

Thanks to all that participated in the Horus Binary telemetry tracking! The participation was excellent and we had excellent balloon position throughout the entire flight and consequently knew exactly where the landing position was (even if it was a bit of a hike to get there). Here are the packet count statistics from all the stations that successfully tracked the balloon:

You can view the full telemetry and statistics here: https://grafana.v2.sondehub.org/d/HJgOZLq7k/basic?var-Payload=KE5GDB&from=now-2d&to=now&orgId=1

The DMR single-frequency repeater (Hytera PD982 HT) generated a lot of traffic with stations as far south as Houston, as far north as Sherman, and east as Tyler and Texarkana. Excellent range as we have come to expect from this payload. Complete recording of the DMR activity coming soon.

We will also have some excellent video soon.

We hope that you had a good time and learned a few things – Thanks for participating!

Video:

Michael Porter KF5LDJ has posted his YouTube video about the launch. Thanks Michael!

Here’s the view of the 360cam showing the moment that the ADS-B payload flew off the payload string. You can follow the payload all the way to the ground (which was ultimately how that payload was recovered the following day).

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Pre-Launch Announcement:

This is just a quick reminder that we’ll be launching the balloon tomorrow morning at Aubrey Middle School in Aubrey TX. Setup begins at 8:00AM and liftoff is at 9:00AM! We fully expect the range of the balloon near apogee to be most of Texas, along with large portions of Oklahoma, Louisiana, and even some Arkansas! Now is a great time to set your radio for the SSTV on 433.5 MHz or the DMR at 441.0 MHz. Bonus points if you can decode the tracking with a sideband radio at 432.630 MHz.

Full information about the tracking software and methods: High Altitude Balloons

Launch site: https://maps.app.goo.gl/gFbNd4CfgbiCUT8q8

Tracking: https://amateur.sondehub.org/ (look for the balloons just north of DFW)

Launch talk-in will be on Allstar node 47841 (Denton 146.92 and Richardson 147.12).