Related Clues:

• Summation signs
• When planes are due, for short
• Cockpit announcements: Abbr.
• Hellenic H's
• Some guesses, briefly
• Terminal figs.
• Airport-board listings: Abbr.
• Brief guesses?
• Station info
• Platonic H's
• ''H'' look-alikes
• Weather may affect them: Abbr.
• LAX stats
• Certain Greek letters
• Zetas' followers