The Vought-Sikorsky VS-300 became the first successful helicopter to fly.
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The people of Estonia voted to approve joining the European Union.
14-year-old Ahmed Mohamed was arrested at school after bringing in a homemade clock, which was mistaken for a bomb.
Singer Selena Gomez shared on Instagram that she had a kidney transplant due to her struggle with lupus.
Mary Ann Fischer gave birth to quintuplets, who became the first US quintuplets to survive past infancy.
The Ottoman Empire signed the Treaty of Adrianople with Russia, which ended the Russo-Turkish War.