EOSS 73 Prediction from 1450 Miles

Ok, so how do you make a balloon prediction when you are 1450 miles from home? As it turns out, it isn't so much of a problem as I first thought it might be.

The internet makes one place much the same as any other with the obvious exception that you aren't physically present at a remote spot and can only gather data relayed from that location by internet enabled devices.

In the case of predicting where a balloon will travel, this is no obstacle at all. While I was sitting in my Father's place in Hilton Head Island, South Carolina, I just fired up my programs on my notebook instead of the desktop machine I normally use and once I was connected to the net did all that I would have done at home. This is so un-noteworthy that I wouldn't have even began this article.

However, there were some much more interesting and exciting things available.

During EOSS's recent flights we have been relaying data into the APRS-IS system on the internet. Specifically, the positional information, as captured aboard the balloon by a GPS receiver and converted into APRS formatted data by the on board Kantronics KPC-3 TNC is transmitted to ground stations which instantly relay it on to the internet.  We do this primarily as a means of keeping the FAA up to date on the current position of the balloon and its payload train. However as a side benefit anyone can have access to near real time data from the flight regardless of their location on planet Earth.

Usually I am sitting somewhere within radio receive range of the balloon. I monitor the flight making comparisons between the actual flight track and the preflight prediction in order to keep the tracking teams appraised as to the accuracy of the prediction. This assists the Tracking and Recovery guys by letting them know that things are going as planned or, the balloon is off on its own and a revised flight prediction is in order to help them to reposition around a different landing spot.

By connecting to Findu.com I was able to download the latest tracking information transmitted by the balloon and keep an eye on things. It turned out that this was especially necessary for the flight of EOSS-73 as we seem to have had some kind of flight hardware failure which resulted in a floating balloon after ascending to a maximum altitude of 40K feet. Since the prediction was based on a nominal flight to 95,000 feet a new prediction was required. Fortunately, I had fairly up to date data. However, bad news, Findu.com became unavailable to me during the float phase. During the point leading up to the failure, I had noted a steady decrease in ascent rate starting when the balloon reached around 30K feet. So, I was fully aware of what was happening and was actually anticipating a question that would come in from the field.

Another interesting aspect to running the prediction center 1450 miles from the flight ... EchoLink. Without the assistance of the Denver Radio Club's 449.350 MHz repeater which is linked into the internet via EchoLink, I would have either had to use the phone to keep Marty up to date on my predictions or more likely, I'd have done it by email. However, with the availability of this repeater, I just sat in my Dad's easy chair with the notebook on my lap and plugged in a headset and kept Marty up to date on the latest prediction information by "radio".

The ground station and the chase teams had decided it would be best to execute a cut down of the payload systems rather than allow it to cruise east in an uncontrolled manner. The FAA was certainly happy with that decision. And so, in came the call I was expecting, "If we cut the balloon down at this point where will it land?" At first I was a bit flustered. I didn't have a live feed and so didn't know exactly where the balloon was. However, I soon realized all the tracking and recovery guys needed was a range and bearing from the cut down location. Armed with this information they could easily compute the actual location on a map. So, I ran the prediction using the winds aloft as observed by our ascending payload and gave the results to Marty. Essentially I was saying if you cut down at 40K feet it will fly around 12 miles on a bearing of 88 degrees true.

That was a pretty good prediction and enabled the T&R guys to preposition themselves for a quick recovery.

All in all, this was a very interesting flight for me even though I was a great many miles distant. If you ever find yourself in the awkward position of being responsible for running predictions and being out of town at the same time, you might actually be able to fulfill your role. I did and I found it fun and pretty easy.