History of Aerospace Engineering

• Unmanned sky lanterns have been documented in use as early as the 3rd Century BCE, in ancient China

• Sky lanterns used during wars to scare enemy troops

2,000 Years Ago

• General Zhuge Liange (181-234 CE) used sky lanterns as a war tactic

• ​Lanterns took flight by an oil lamp or waxy flammable material being lit on fire under paper lantern

​Why do lanterns float?

• The flame heats the air inside the bag, making it less dense than the air outside of the bag, which causes the bag to rise

• These particular "lanterns" are some of the oldest forms of hot air balloons in history

• Density is the degree of compactness of a substance

• The density of material shows the denseness of that material in a specific given area.

• A material’s density is defined as its mass per unit volume.

• Density is essentially a measurement of how tightly matter is packed together.

• It is a unique physical property of a particular object.

• The principle of density was discovered by the Greek scientist Archimedes.

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• September 19, 1783

• 1st hot air balloon flights with passengers launched

• Montgolfier Brothers

• Made of paper and cloth in Versailles, France

• To inflate the craft they burned combination of straw, chopped wool, & dried horse manure underneath the balloon

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​200 Years Ago

• As the straw burned it released heat that helped the balloon float

• Wool & manure made lots of smoke and helped keep the burning flame low

• The Brothers were too nervous to try out invention so they sent a sheep, duck, and a rooster

• Balloon traveled about 2 miles and safely landed 8 minutes later

​Montgolfier Brothers