Possible Clues:

• Onetime name atop N.Y.C.'s MetLife Building
• Clipper name
• Former intl. airline
• Its first route was Key West-Havana
• Old rival of 41-Across
• Former company with a globelike logo
• First airline with commercial transpacific passenger flights
• One-time intl. airline
• First commercial carrier to use the Boeing 747
• Yankee Clipper company