On to "Inflation"

No, this won't be a lesson on the economy... it's time to get Aurora ready for launch.

Once everyone's assembled at a suitable launch site, the fun begins. Dave is usually assisted by three crewpeople (though it can be done with fewer if you'd like to help!). It'll only be a few minutes now 'til we're airborne, so let me explain what you're seeing out there on the field...

When we first arrive, you may be a bit puzzled. The balloon basket arrives on a trailer, along with an inflator fan... but where's the envelope? Few people are aware that this fabric bag, which holds 75,000 cubic feet of air, can be compacted into a pack-up bag (similar for all the world to a sleeping-bag packsack) weighing around 125 lbs. and occupying only a couple cubic feet of space in the back of the chase vehicle. Once we're all assembled, the basket and fan are unbolted from the trailer, and the pilot will test the surface wind by launching a pibal- a garden-variety toy balloon (usually black) filled with helium. Careful observation of this balloon as it rises will give a fair indication of the direction of flight and wind currents aloft. This also helps us determine the best way to lay out the balloon for inflation.

The process starts with laying the envelope out on the ground with the mouth facing the direction from which the wind is blowing. Before this is done, the pilot and crew check the ground to be sure there are no rocks, sharp objects, or other debris that could tear the fabric. Next,two crew members are assigned to hold the balloon open at the mouth, so that cold air from the fan can be used for the first stage of inflation.

Next, the cables connecting the envelope to the basket are attached, and the fan is started. One crew member supports the skirt on each side, at the same time keeping a foot on the skirt where it touches the ground to prevent cold air from rushing underneath. Instead, all is directed inward, and the balloon is cold-air inflated in from five to ten minutes. Crew members generally wear gloves to protect their hands from abrasion by the cables if the balloon should shift abruptly during inflation.

While cold-air inflation is going on, the pilot or crew chief seals the valve, or parachute top of the balloon, and does a general walk-around to be sure that the envelope is filling smoothly and evenly. He also will pull out the sides of the envelope manually to hasten the inflation process.

Meantime, an additional crew person or two are manning crown lines that stretch about 50 feet from the crown of the envelope. They are responsible for controlling the balloon during the entire cold-air inflation process. By moving appropriately, they keep the balloon from rolling from side to side if crosswind breezes or gusts should hit. Additionally, once the pilot turns on the burner for hot-air inflation, the crown people provide the "ballast" to prevent the envelope from rising too quickly. They also keep an eye on spectators, to make sure no one will be in the way when the balloon comes upright. This process happens quickly, and unwary spectators could easily become tangled in or trip on a line.

Balloons can inflate in close proximity to each other, provided everyone's paying attention and doing their jobs.