We use latex party balloons in five different sizes(see left).
The larger the balloon, the more lift it provides which means
it will go higher in the atmosphere and hopefully travel a
greater distance.
When using a 9" balloon you may need to tie two of them together to get any lift at all, but if you tie any size balloons together the wind wisps the balloons around more rather than them just going in a straight direction in flight.
Nine and 12 inch balloons will not gain altitude very quickly which
makes them subject to become caught in surrounding trees or other
obstructions. We have used 16" the most because they are the largest
for the best price. A bag of assorted color 16" balloons cost about $5
The more you inflate your balloon with helium, the greater the risk of balloon bursting if it comes in contact with a tree branch. Also, when filling a 16" or larger balloon with helium, try to leave enough room for the helium to expand in the heat of sunlight or from the decrease in atmospheric pressure as the it rises in the atmosphere which could cause the balloon to burst.
Mylar balloons are the shiny foil-like balloons. We have used mylar
balloons twice. One was a leftover "Happy Birthday" balloon and the
other was a $6 jumbo blimp that said "Congrats!". The only advantage
to mylar balloons is can hold their helium for weeks, where as latex
balloons can only hold their helium for a few hours depending on the
size and quality. Mylar costs about $5 for one balloon. A disadvantage of mylar
is that they don't expand in heat or low air pressure which could cause them to
burst. The major problem with mylar balloons is that they can conduct electricity.
They could cause serious problems if they got entangled in power lines.
There is even a warning printed on the balloon thats says not to release it
outdoors. We were not aware of this at first, but we don't plan on releasing
anymore mylar balloons.
If you really want your balloon to fly a really long way, you might consider buying a 60" balloon or even a weather balloon. Sixty-inch latex balloons cost about $7. We have one, but we haven't used it yet. Weather balloons cost about $10 - $15 in sporting good catalogs. It would probably take 2-3 medium size tanks of helium to fill a weather balloon, but they provide 6 pounds of lift. With a weather balloon, you could send up a lot more than just a card and envelope.
One idea that we haven't tried yet, is to use a large trash bag and
fill it with as many helium-filled latex balloons as it will hold,
and then tie the bag shut. We would then tie our balloon card to the
knot in the trash bag. This would make one large balloon. It would
have much more lift and have more surface area for the wind to push
against. If a one of the latex balloons bursted, the helium would stay
inside the trash bag if it was sealed proporly.
Some people are allergic to latex balloons, click here for more information.
If you questions or comments about balloons, please e-mail me.