So you've put together a nice package of cameras and sensors, and plan to launch your hard work skyward. Thanks to publicly available winds-aloft data, you have a pretty good idea where it will come down... but what if Mother Nature throws you a curveball? With so many unknowns - the burst altitude, the exact speed and direction of the wind, equipment malfunctions that could cause you to lose contact with the craft - your payload could end up almost anywhere. Will your recovery team be able to stay in front of the device as it flies downrange? Will you need additional cars in the chase team for contingencies?
The Balloon Recovery Simulator is a tool that may help you explore these scenarios.
BRS is a Google Maps-based app specifically intended to simulate a high-altitude balloon mission. You are the commander of the recovery mission, and it is your job to dispatch the chase cars in the field, so that they can be close to the balloon when it comes down, while also ensuring that you have options in reserve in case the balloon flies farther and faster than you expect.
Yours is a tactical view of the mission - you will see where the balloon is, and where your chase cars are, on Google Maps. You decide where each chase vehicle will be positioned at launch time, and as the mission progresses, you can send each vehicle to new destinations, or order them to stop in their tracks, at any time. Your vehicles' rates of travel across the map are realistic, based on the roads and terrain they are driving through. This limited travel speed is what makes the game challenging - just as in a real recovery, you have to anticipate where the balloon will go next and how quickly it will get there, then watch anxiously as your team tries to get there in time. It's a lot harder than you might think!
Here's how to play (or feel free to dive right in).
1. First, you'll need to provide some data about the winds aloft. A link to the University of Wyoming balloon track calculator is provided. On their site, enter the details for your flight, then copy the resulting data (without the headers) and paste it into the data field of the BRS. For your first time out, though, skip all of that and just click the "Use test data" button to populate the data field automatically. BRS will show your launch point, your estimated landing point. Bear in mind, though that just like a real balloon the ACTUAL landing point in this simulation may be quite different!
2. Next, decide how many chase cars you would like to have (one to four), and where those cars should be stationed when the balloon is launched. If you are using the test data, you might want to start your cars in the towns of Charlottesville, Crewe, and South Boston, plus one at the launch site (so that your launch team can also help with recovery). You can use the drop-down list to select from a few likely towns in central Virginia, or type in a location for Google Maps to geocode. For city names, be sure to include the state (eg., "Schuyler, VA").
3. Now that everyone is ready, it's time to start the simulation! Click "Play" on the control panel to launch the balloon and start the clock. The elapsed time within the game will begin ticking away at roughly 10x normal speed. You may click "Pause" at any time to stop the clock. Selecting a new destination for a chase car automatically pauses the simulation (so you won't miss anything!). Once you have made your selection, the clock will resume automatically.
4. While the clock is running, you will see telemetry come in from the balloon at various intervals, updating its location. Keep an eye on it's flight path and speed - it may be flying very differently from the predictions!
Your chase cars will also start to move once you have given them destinations. The cars move at a realistic speed (matching the speed of the simulation), so you may need to zoom into the map to see them moving. Naturally they will drive quite a bit faster on highways than on city streets. They may even encounter traffic jams. Once they arrive at destinations you provide, your chase cars will stop there and wait patiently for further instructions. To specify a new destination, you can again use either common cities in the drop-down list, or type in a new city name or address. You may also be able to name an intersection... but note that if you use something super-common ("10th and Main"), there's no telling which city Google Maps might pick. To be safe, always enter the city name ("10th and Main, Lynchburg, VA"). If you find that your driver starts heading off in the wrong direction, you can either stop him in his tracks (New destination... Stop at current location), or simply give him the destination you originally intended, but perhaps with a bit more detail (so not "Cumberland", but "Cumberland, VA").
5. Eventually your balloon will succumb to the high altitudes. Once it bursts, the payload will begin to descend very rapidly (descent parachutes are not effective until the payload has free-fallen a few miles). You will see the climb rate display go negative and turn red... and now the pressure really starts! You have a limited amount of time to get your cars as close as possible to the balloon as it comes down, so that they can either spot it visually, or begin tracking it using RDF techniques. Just like in real life, your cannot tell your drivers to drive at dangerous speeds - you will need to make a good educated guess about where the payload will land, and have your cars nearby to intercept.
6. Assuming all goes well, the balloon will return to the Earth two or three (simulated) hours after launch. When it does, its climb rate will become zero, and its altitude will reflect the elevation of the landing zone. To get your chase cars as close as possible, you may want to start using intersection descriptions as the vehicles' destinations. At this point, you may also want to switch your Google Maps display to Satellite, to get an idea what kind of conditions your recovery team will face. Is your gear up in a tree? Behind a hill? On the roof of a mall? Twenty miles out to sea? Take a look, and imagine how you would explain to a real recovery team how to get to the equipment.
The simulation will run for a couple of (simulated) hours after touchdown, to give your team a chance to get to the scene even if they were way out of position.
Now you're ready - click here to start your mission!
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After your time expires, think about what you have seen. Did things go as expected? Was the flight/landing prediction useful? Do you maybe need an extra car WAY downrange in case the winds pick up? Did your cars go where you expected, taking the routes you expected? Would you have staged them in different locations? Feel free to run the simulation again with different data, or even with the same data - the results will be different every time, giving you an opportunity to see and learn from different scenarios.