Probably several (not least Korra herself, whose habitual memo style was unsurprisingly well-known for its informality), but the shortest memo in the project's history was actually written by the Propulsion Specialist, Koharu Shimizu, during personal equipment testing in 197 ASC. Not counting the headers, salutation, and closing, it consisted of one word:

FROM: SHIMIZU Koharu
TO: Materials Selection
IN RE: Flightsuit Sample #23-05

Guys,

Nope.

SHIMIZU

Attached to the bottom of the sheet was a charred fragment of what had been a swatch of the supposedly fireproof material the crew flightsuits were to be made from.

--G.
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Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
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