Indoor Ballooning

What does a model balloonist do, whose hobby is no doubt very much depending on the weather, when it's rainy and stormy for weeks and weeks?
We once had experimented with balloons made of very thin paper, but due to the relatively high weight of that paper, the balloons couldn't be made smaller than a certain size, and the fire danger was also quite high ;-)
Finally, the solution to that problem was: Dustbin foil!

As these balloons are very popular wherever we fly them, and also are quite suitable to start this hobby with, you can find some hints for do-it-yourself building here.

The envelope

a good looking envelope means a lot of work...
The envelope is probably the most difficult thing about an indoor balloon, as far as you want it to look good. In fact, a turned-around dustbin bag would do as well, as long as it's light enough.

Our indoor balloons all consist of dustbin or painting protection foil, which is welded together with a soldering iron. With a weight of only 7 g/m², the painting protection foil is probably the lightest material available to build balloons with. The coloured dustbin bags have an average weight of 15 g/m² and are therefore only suitable for a bit bigger balloons.

The burner

As a burner, we use a tuned soldering torch or self-made constructions, depending from the size of the envelope.

This one here was made out of a 'pencil torch solder' which can be found in every do-it-youself store. The spiral spring was only attached for design reasons. The burner frame was made out of aluminum sheet, it is mounted on four aluminum tubes which are glued to the bottom of the basket (wooden board). The burner is connected to a gas bottle with an adjustable valve by a long, thin plastic hose. Gas bottles with adjustable valves are available at home stores also.
the burner

The basket

the smallest basket
As any other indoor balloon equipment, the basket has to be as light as possible. For the small indoor balloons, where you hold the burner in your hand, baskets are made out of paper or cardboard. This one comes from a paper kit.

If the burner is mounted on the basked (see above), more solid materials have to be used, of course. However, the wall of the basked can always be made of paper or cardboard.

Some of our indoor balloons

Here you can see some of the envelopes which we built over the years. The most difficult and also last project was 'Herbert the rabbit' which was built after a little soft toy animal.
This balloon has even got his own transportation vehicle
The smallest hot air balloon of the world is flying in our living room
Special shapes do work as indoor balloons, too - here a beer glass
The indoor penguin balloon
The little toy animal enjoys the view from the basket. You can see the pencil torch burner held in hand by the operator.
Herbert the rabbit

This little soft toy animal was the model for the indoor balloon

Fascination indoor ballooning at the model balloon meeting at Brigachtal