On October 16, Coloradans (including me)witnessed what appeared to be a little boy floating above the ground in a saucer shaped balloon. Some people have suggested this is a hoax. There are no solid indications of this, so the TV stations both local and national followed this story as though there actually was a little boy in this saucer balloon.
What is disturbing is the lack of a reality check by these stations. Some simple engineering calculations show that the likelihood of a little boy being taken aloft by a ballon of this size is remotely small.
And yet, the TV stations seemed to be more interested in the sensationalism of the story, rather than the reality. They were buoyed by reports that the sheriff had talked to someone at CSU who claimed that the balloon could lift 80 pounds. Either the Sheriff's department asked the wrong questions or someone at CSU needs to take some classes.
Do you think there could have been a boy in the saucer balloon? As an Aerospace engineer, I did some calculations to see what the real possibilities are.
The saucer shaped ballon is about 6 meters in diameter and 2 meters high at the thickest point. If the balloon were a cylinder, it could hold about 56 cubic meters of helium. But, it is highly tapered especially on the bottom, so I will conservatively knock off a 1/3 of this volume.
balloon volume --> about 37.7 cubic meters
At ground level, 37.7 cubic meters can support about 37.7 kgs of mass. But, that means support, not fly or climb with.
But, let's investigate that idea of ground level. Without allowing for Colorado's ground level, the mere fact that this device climbed to 3,500 feet above the ground (maybe more) means that the lower density at altitude will allow less weight or mass to be carried by the balloon. About 15% less.
balloon total weight at altitude --> 32 kg
In fact, the weight the ballon could carry would be less due to the mile high ground level as the starting point. But, we are being ultra-conservative in these calculations.
A couple of other factors to consider: the saucer was not completely filled with helium taking advantage of the full volume, although we have assumed this to be the case. Also, filling a balloon with helium without allowing heavy air to leak in is very, very difficult. It is not unusual for the real lifting power of a balloon to be half of simple assumptions. But here, we will only knock off another 10%.
total possible balloon weight --> 28.9 kgs
or 62 lbs
Now, this must include the weight of the balloon and all equipment, plus the weight of the boy.
How much does a large mylar balloon weigh? How about with those 2 or 3 longrope lines that were trailing the balloon? 10 lbs, 15 lbs?
A balloon this light could only be built with materials so flimsy that a boy in the tiny capsule under the balloon could not be structurally supported. To support any significant weight would increase the total ballon structure weight to 25 lbs or so. We are now in pounds rather than kilograms:
63 lbs - 25 structural lbs --> 38 lbs payload
So this leaves 38 lbs for a 6 year old boy, including his clothes or the balloon will not readily leave the ground. Highly unlikely, given this is the maximum weight due to the very conservative nature of these calculations.
And the father was very concerned about the boy being electrocuted, apparently due to high-voltage equipment in the capsule. We didn't account for this. So, if there is *any* equipment on board, there is no weight allowance left for the boy.
And, the helicopter video of the saucer floating at 3,500 feet showed a third of the helium envelope collapsed. This would have reduced the total weight of balloon and boy from 63 pounds to 42 pounds. Obviously, there could have been no boy on board at that time.
So, if the authorities had asked an engineer or experienced balloon pilot, they could have been told there was only a very remote chance there was any little boy on board this saucer balloon.
But, the authorities didn't want to know this, and neither did the TV stations carrying this sensational news live.
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