We're just coming back from a rather unsuccessful Sunday afternoon of balloon mapping in Mexico City's beautiful Chapultepec park. In the spirit of learning from other people's mistakes, we'd like to share how we could have gotten the balloon in the air where we wanted:
1. Get enough helium
The pink one-way bottles of helium that you see in the first picture are commonly sold in Mexico City, but one of them won't be enough for filling your kit balloon. You'll see the balloon fly in the last picture, but that's without a camera. Get a larger bottle, or at least two of those for a fill, which might be easier.
2. Get a permit
If you look at the pictures below, you'll see first the police idling as we're inflating the balloon, but then intercepting us before we can fly it. The day being a Sunday, we were told to get a permit at the Park Authority on Tuesday or Wednesday. We tried to convince the police what we were doing wasn't an "actividad" (requiring a permit), put rather "jugar" = play. They didn't buy into our pitch. Neither had they heard of OpenStreetMap or OpenAerialMap before, effectively delivering the fatal blow to us mapping Chapultepec that day.
I recommend double checking the date and calling ahead if you'd like to get that permit.
I hope I could share some useful information for your next Mexico City park mapping trip. Here are the pictures, they neatly tell our story.
