The hot air balloon or war balloon is an experimental weapon that the mechanist originally developed for the Fire Nation in exchange for the safety of the Northern Air Temple. The mechanist had difficulty figuring out how to control the balloon, but resolved this issue with assistance from Sokka. The key was creating a small valve in the top of the balloon that allowed the pilot to release the hot air at will, thereby controlling the up and down movement of the balloon.
The mechanist and Sokka used a war balloon against Fire Nation soldiers attempting to invade the Northern Air Temple by dropping bombs on them. Having run out of bombs, they used the ship's furnace as an explosive to detonate a gas pocket in a nearby chasm, causing a huge explosion that forced the invaders to retreat. Their victory also caused the balloon to lose altitude due to the loss of its heat source. The mechanist and Sokka were forced to abandon it in mid-flight, enabling War Minister Qin to capture its remnants later on in the woods. Upon discovering the remnants of the balloon, Qin stated, "This defeat is the gateway to many victories."
After the failed invasion on the Day of Black Sun, the Fire Nation unleashed a whole armada of these war balloons on the invaders. Much to the mechanist's despair and that of the rest of the invasion force, the troops discovered that the War Minister had adapted the war balloon's technology for use on the newer and much larger Fire Nation airships. These were used to bomb the invaders' submarines, trapping them on the Fire Nation mainland. After the invasion failed, Zuko commandeered one of these balloons to follow Aang and his friends all the way to the Western Air Temple so he could join them.
Before Zuko was accepted into the group, he used the sail of his balloon as shelter. Later, he used the balloon again when he and Sokka traveled to the Boiling Rock Prison to save Sokka's father, Hakoda. The balloon was destroyed in a crash landing when the intense heat from the surrounding boiling lake equaled that of the balloon's heat and rendered it unable to fly. Sokka disposed of the wreck in the boiling lake to prevent the prison guards from finding it, where it was lost forever.
A year after the Hundred Year War, the Earth Kingdom acquired the specifications for hot air balloons and incorporated the aircraft in their own line of warfare, albeit modified to now sport the Earth Kingdom emblem and colors. One such unit was used to transport Earth King Kuei to Yu Dao, a strategy which would allow him to command his army from the front and enforce the Harmony Restoration Movement.
A crew of two firebenders typically work together to operate the balloon: one to keep it in the sky by controlling the heat and the other one in charge of its offense by attacking enemies below or flying near the balloon.
- ↑ From older Avatar: The Last Airbender official site, originally on Nick.com (link). No longer updated.
- ↑ "The Northern Air Temple". Elizabeth Welch Ehasz (writer) & Dave Filoni (director). Avatar: The Last Airbender. Nickelodeon. November 4, 2005. No. 17, Book One: Water
- ↑ "The Day of Black Sun, Part 2: The Eclipse". Aaron Ehasz (writer) & Joaquim Dos Santos (director). Avatar: The Last Airbender. Nickelodeon. November 30, 2007. No. 11, Book Three: Fire
- ↑ "The Western Air Temple". Elizabeth Welch Ehasz, Tim Hedrick (writers) & Ethan Spaulding (director). Avatar: The Last Airbender. Nickelodeon. July 14, 2008. No. 12, Book Three: Fire
- ↑ "The Boiling Rock, Part 1". May Chan (writer) & Joaquim Dos Santos (director). Avatar: The Last Airbender. Nickelodeon. July 16, 2008. No. 14, Book Three: Fire
- ↑ Gene Yang (w), Gurihiru (a). The Promise Part 2 (May 31, 2012), Dark Horse Comics