AD 3

AD 3 or AD-3 may refer to:

• A year of the 0s decade in the in the Julian calendar
• Salmson AD.3, an aircraft piston engines of the 1920s
• Adaridi AD 3, a Finnish experimental aircraft of the 1920s
• AD-3, the third production variant of the Douglas AD Skyraider aircraft
• One of the experiments running on the Antiproton Decelerator
• USS Dobbin (AD-3), a US Navy destroyer tender