No known species of reindeer can fly. BUT there are 300,000 species of living organisism yet to be classified, and while most of these are insects and germs, this does not COMPLETELY rule our flying reindeer, which only Santa has ever seen.
There are 2 billion children (persons under 18) in the world. But since Sanata doesn't (appear to) handle the Muslim, Hindu, Jewish and Buddist children, that reduces the workload to 15% of the total - or 378 million according to the Population Referance Bureau. At an average (cencus) rate of 3.5 children per household, that is 91.8 millions homes. One presumes there's at least one "good" child in each.
Santa has 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 822.6 visits per second. This is to say that for each Christian household with good children, Santa has 1/1000th of a second to park, hop out of the sleigh, jump down the chimney, get back into the sleigh and move on to the next house. Assuming that each one of these 91.8 million stops are evenly distributed around thwe earth (which, of course, we know to be false, but for the purpose of our calculations we will accept), we are now talking about .78 miles per household, a total trip of 75 and a half million miles, NOT counting stops to do what most of us must do at least once every 31 hours, plus feeding etc. This means Santa's sleigh is moving at 650 miles per second, 3000 times the speed of sound. For purpose of comparison, the fastest man made vehicle on earth, the Ulysses space probe, moves at a poky 27.4 miles per second - a conventional reindeer can run, tops, 15 miles per hour.
The payload on the sleigh adds another interesting element. Assuming that each shild gets nothing more than a medium sized Lego Set (2 lbs), the sleigh is carrying 321,300 tons, not counting Santa, who is invariably described as overweight. On landing, conventional reindeer can pull no more than 330 pounds. Even granting that "flying reindeer" (see point 1) could pull TEN TIMES the normal amount, we cannot do the job with eight, or even nine reindeer. We need 214,200 reindeer. This increases the payload, not even counting the weight of the sleigh, to 353,430 tons! Again for comparison - this is four times the weight of the Queen Elizabeth!
353,430 tons travelling at 650 miles per second creates enormous air resistance. This will heat the reindeer up in the same fashion as space craft re-entering the earths atmosphere. The lead pair of reindeer will absorb 14.3 QUINTILLION joules of enery ... per second ... EACH! In short, they will burst into flame almost instantaneously, exposing the reindeer behind them, and creating deafening Sonic Booms in their wake. The entire reindeer team will be vapourized within 4.26 thousandths of a second. Santa, meanwhile, will be subject to centrifugal forces 17,500.06 times greater than gravity. A 250 pound Santa (which seems ludicrosly slim) would be pinned to the back of his sleigh by 4,315,015 pounds of force.
In conclusion - If Santa ever DID deliver presents on Christmas Eve ...
he's dead now :-)
[This was extracted from cafe.australia who pinched it from SPY magazine January 1990!]