Santa Claus: An Engineer's Perspective:
I. There are approximately two billion children (persons under
18)in the world. However, since Santa does not visit children of Muslim,
Hindu, Jewish or Buddhist religions, this reduces the workload for
Christmas night to 15% of the total, or 378 million (according to the
Population Reference Bureau).
At an average(census) rate of 3.5 children per house hold, that
comes to 108 million homes, presuming that there is at least one good
child in each.
II. Santa has about 31 hours of Christmas to work with, thanks to
the different time zones and the rotation of the earth, assuming he
travels east to west (which seems logical). This works out to 967.7
visits per second. This is to say that for each Christian household with
a good child, Santa has around 1/1000th of a second to park the sleigh,
hop out, jump down the chimney, fill the stockings, distribute the
remaining presents under the tree, eat whatever snacks have been left
for him, get back up the chimney, jump into the sleigh and get on to the
next house.
Assuming that each of these 108 million stops is evenly
distributed around the earth (which, of course, we know to be false, but
will accept for the purposes of our calculations), we are now talking
about 0.78 miles per household; a total trip of 75.5 million miles, not
counting bathroom stops or breaks. This means Santa's sleigh is moving
at 650 miles per second  3,000 times the speed of sound. For
purposes of comparison, the fastest manmade vehicle, the Ulysses space
probe, moves at a poky 27.4 miles per second, and a conventional
reindeer can run (at best) 15 miles per hour.
III. The payload of the sleigh adds another interesting element.
Assuming that each child gets nothing more than a medium sized
Lego set (two pounds), the sleigh is carrying over 500 thousand tons,
not counting Santa himself. On land, a conventional reindeer can pull
no more than 300 pounds. Even granting that the "flying" reindeer could
pull ten times the normal amount, the job can't be done with eight or
even nine of them  Santa would need 360,000 of them. This increases
the payload, not counting the weight of the sleigh, another 54,000 tons,
or roughly seven times the weight of the Queen Elizabeth (the ship, not
the monarch).
IV. 600,000 tons traveling at 650 miles per second crates enormous
air resistance  this would heat up the reindeer in the same fashion
as a spacecraft reentering the earth's atmosphere. The lead pair of
reindeer would absorb 14.3 quintillion joules of energy per second each.
In short, they would burst into flames almost instantaneously, exposing
the reindeer behind them and creating deafening sonic booms in their
wake. The entire reindeer team would be vaporized within 4.26
thousandths of a second, or right about the time Santa reached the fifth
house on his trip.
Not that it matters, however, since Santa, as a result of
accelerating from a dead stop to 650 m.p.s. in .001 seconds, would be
subjected to centrifugal forces of 17,500 g's. A 250 pound Santa (which
seems ludicrously slim) would be pinned to the back of the sleigh by
4,315,015 pounds of force, instantly crushing his bones and organs and
reducing him to a quivering blob of pink goo.
V. Therefore, if Santa did exist, he's dead now.

