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As we all know, Santa loads his sleigh with gifts for millions of children around the world and sets about distributing them during the night of December 24/25. To make them all fit in his stylish truck-sized sleigh, he obviously uses the same compression technology that enables him to jimmy up and down chimneys, infiltrate through A/C units, drink milk and eat cookies while evading bio-containment filters, intruder alarms, and such. We won't worry about that at the moment, but we can assume that the device does not modify mass (otherwise it would break all sorts of conservation laws, and make our physicists look silly indeed).

santa sleigh

How much does Santa's sleigh weigh when he sets off with a full load from the North Pole? Specifically, is it heavier than the USS Gerald R. Ford aircraft carrier?

Bonus questions for extra credit:

  1. Estimate the per reindeer power output level that allows the fully-loaded sleigh to perform essentially VTOL.
  2. Total dollar value of the presents, and the size of the annuity needed to pay for them each year. (For simplicity, the manufacturing Elves can be assumed to be enslaved by Sandy Claws, to require no maintenance and to have no form of organized labor activity)
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  • $\begingroup$ Are you just looking for an equation? Seems like there would be some wildly uncertain variables here... $\endgroup$ – apaul Dec 15 '15 at 0:10
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    $\begingroup$ @apaul34208, I was hoping for a Fermi approximation? $\endgroup$ – Serban Tanasa Dec 15 '15 at 0:11
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    $\begingroup$ It's actually a rather small part of the world where Santa brings presents on the 24th/25th. In many places Santa shows up at different dates. Or the Christmas presents don't come from Santa, but (what boils down to) the holy spirit (and Santa is just punishing kids). Then there are all the Orthodox Christians, Muslims, Jews, Hindus, Buddhists, you-name-it, - they don't have Santa either... $\endgroup$ – fgysin Dec 15 '15 at 10:27
  • $\begingroup$ @fgysin Orthodox Christians have a Santa (Mos Craciun or Ded Moroz), and, at least where I was born, it arrives on Dec 24/25. $\endgroup$ – Serban Tanasa Dec 15 '15 at 12:42
  • $\begingroup$ @Serban Tanasa: My bad, must have mixed something up. $\endgroup$ – fgysin Dec 15 '15 at 13:12
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Okay, let me take a shot at this.

Let's figure out some unknowns first:

  • What is the weight of all the presents?
  • How many kids in the world?

When you say Santa leaves the North Pole on a full load, let's assume he means to deliver some Christmas cheer to every kid in the world.

Based on this website here, there are 1.9 billion children in the world right now. Now, we can assume each kid gets 2 presents and that each present is 2 lbs. With that information we get:

1,900,000,000 x 4 lbs. = 7,600,000,000 lbs [3,447,337.38547 metric tons]

wow.....

That is a scenario where every kid is a good kid and none are bad...

Now the USS Gerald R. Ford aircraft carrier weighs about 100,000 metric tons. Comparing that with our calculations, Santa's sled is WAY HEAVIER, by about 3,347,337 metric tons.


But in an ideal scenario, not every kid is good. Let's say that 1 in 15 kids is on the naughty list:

1,900,000,000 kids x 1/15 ratio of bad kids to good kids = 126,666,667 bad kids

Now every bad kid gets some coal from Santa, let's say a 3 lb. lump of coal

126,666,667 x 3 lbs. = 380,000,001 lbs. [172,365.1 metric tons]

BUT there are still some good kids in the world, about 1,773,333,333 left.

1,773,333,333 x 4lbs. = 7,093,333,332 [3217481.87 metric tons]

So in all the weight in a realistic situation would be:

3217481.87 metric tons + 172365.1 metric tons = 3,389,846.97 metric tons

Which is still heavier than the USS Gerald R. Ford aircraft carrier, and the sleigh is even heavier than if all the kids were good in the world.

Note: my first answer is based on the fact every kid in the world gets a present.

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  • $\begingroup$ Every? What about bad kids? $\endgroup$ – JDługosz Dec 16 '15 at 6:01
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    $\begingroup$ @JDługosz Coal isn't massless... $\endgroup$ – Scott Downey Dec 16 '15 at 10:29
  • $\begingroup$ @JDługosz hmm... I'll edit the answer. $\endgroup$ – Kit Dec 16 '15 at 21:41
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    $\begingroup$ 1 in 15 on the naughty list is hardly worth recalculating for. You replaced a 4 pounds of present with a 3 pound lump of coal (that's a lot of coal), reducing the total weight by 1/60th (just over 1%). 1/15 * 1/4 = 1/60. You also incorrectly calculated the mass difference to the aircraft carrier. 3,447,337 - 100,000 is not 3,447,237 (you subtracted 100, not 100,000). $\endgroup$ – Draco18s Dec 16 '15 at 22:13
  • $\begingroup$ You're using "ideal scenario" for two different scenarios which is awfully confusing. Could you take a look at your answer and clarify it? $\endgroup$ – Mast Dec 23 '15 at 8:22
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NORAD has been tracking Santa for years. According to their website (under the library), Santa's sleigh weighs 75,000 gd before flight, and 80,000 gd at landing (due to snow and ice accumulation).

Additionally, Santa is 260 lbs before landing and 1260 lbs after, and the gifts 60,000 tons.

(Why Norad is using different units for each thing is beyond me.)

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    $\begingroup$ Because NORAD is a joint effort by the U.S. (we can't ever settle on one thing) and Canada (which uses British measurements, which we don't want to use). $\endgroup$ – Frostfyre Dec 15 '15 at 0:42
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    $\begingroup$ Consulting sites for gumdrops, I see that 40 gumdrops per pound is occasionally referenced. So 75000 gd is about 1875 pounds. $\endgroup$ – Gary Walker Dec 15 '15 at 2:04

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