There are two primary considerations for the balloon launch:
1. Determining the launch location
2. Detailing and following a set of launch procedures
Determining the launch location
Your balloon will likely travel far, maybe more than 100 miles or further from the launch site. You'll need to carefully choose a location such that you have the best chance for a successful recovery.
For flight prediction, the University of Wyoming has a great site that leverages high wind forecast from the GFS to predict the flight path, burst location, and landing site of your high altitude balloon.
Here is the site: http://bit.ly/YzRj1T
For the model, you'll need to specify four inputs
1) Model forecast date and time (Universal Time) which should correspond roughly to your launch date/time. An explanation of Universal time is here: http://bit.ly/10dZTNW
2) The latitude and longitude of your expected launch location. As a starting point you can use your local park. A very handy way of getting the latitude and longitude of any location is to first find the location in Google Maps (https://maps.google.com/), then right click on it and select "What's here?". In the search bar you'll see the lat/long of the site.
3) The expected balloon burst altitude. The balloon manufacture should provide a range for this. As an example here are the Kaymont numbers: http://bit.ly/11bsn29 If you have time, model both the lower and upper range of the burst altitude. Otherwise take the average for the model.
4) The desired output format. I found the Google KML format to be most useful as you can visualize the expected flight path which helps when you need to re-adjust the location. You'll need to install Google Earth to see this data: http://bit.ly/10jiER2
And now the fun begins!
Select "Submit" to run the model. Save the KML file to a local folder and when you double click on the file, the flight path will be displayed in the Google Earth application.
If you are extraordinarily lucky, the predicted landing location of the balloon will be in a nice flat field devoid of trees, mountains, bodies of water, housing developments and other similar obstacles that will prevent you from retrieving your balloon. The more likely scenario is that the program will predict your landing in a location with a number of hazards. If so, select a new location and keeping running the model until you find a good launch location.
Parks, school playgrounds, and empty fields are generally good launch sites as long as there are no large trees present downwind of the launch.
It's really important to practice this process multiple times prior to the launch so that you get the hang of it. Once you have the location finalized, you'll need to inform anyone else who is planning to come help with the launch and recovery.
It's best to plan for an early morning launch as the lower altitude winds are light, and there are few people in the parks to bother you during the launch process.
Detailing and following a set of procedures for the launch process
There are a surprising number of steps required to launch a balloon and there are a number of items you'll need to launch it.
It's really critical to detail these steps into a set of written launch procedures and walk through these procedures with the team. You'll need at least one other person and ideally two people to help you with the launch. You need to walk them through the launch process before the day of the launch and assign your team members specific roles so they understand exactly what to do. The launch process is quite exciting and it's easy for the team to get distracted so that's why it is so important that each person knows exactly what they are expected to do.
There are also many items needed for the launch. It's critical to detail each item into a checklist and then assemble those items the night before the launch to ensure you will be ready. I like to put those items into a launch bag so that everything is properly organized.
You can use the launch procedures and checklist below as a starting point. We borrowed heavily from L. Paul Verhage's guide (http://bit.ly/12DoWvs) and made modifications to fit the specifics of our mission.
If you have kids at the launch, you'll need one adult dedicated to managing them in about a four to one kid to adult ratio. The kid wrangler(s) will be responsible for explaining the launch process and keeping the kids away from the balloon and launch equipment. Also they should ensure all kids are fed, watered, and have had their bathroom break prior to the launch. The balloon chase can take a couple of hours of continuous driving and there will be little time for making bathroom and food stops.
I've seen some debate about the merits of using hydrogen gas rather than helium because helium is a rare, non-renewable resource. While this is true, hydrogen is highly flammable and in my opinion far too dangerous to handle (remember the Hindenburg?). My recommendation is to stick with helium as it's very safe to work with and if you are concerned about the environmental impact, skip the party balloons for your child's next birthday.
Filling the balloon
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|12k||v. 2||Nov 7, 2012, 10:07 PM||Michael Graves|
|12k||v. 2||Nov 7, 2012, 10:06 PM||Michael Graves|
|14k||v. 2||Nov 7, 2012, 10:06 PM||Michael Graves|
|13k||v. 2||Nov 7, 2012, 10:06 PM||Michael Graves|