Related Clues:

• P, on a fraternity jacket
• Forum letter
• Airport posting: Abbr.
• JFK letters
• 7th Greek letter
• Symbol for viscosity
• Metal core?
• When tripled, a crew member's fraternity?
• In-flight info
• In-flight announcement
• Pi Sigma separator
• When a plane is due in: Abbr.
• H, in Greece
• Homeric H
• Pi's successor