Did you really mean "airplane" - or did you mean airline . -If airline it is Qantas.
A Navy Flight Surgeon uses this very insignia. Airline, I do not know.
Lufthansa. It's a German airline
This aeroplane would belong to QANTAS, the national airline of Australia.
Shamrock, Wisconsin Shamrock, West Virginia Shamrock, Virginia Shamrock, Texas Shamrock, Pennsylvania Shamrock, Oklahoma Shamrock, New York Shamrock, Colorado Shamrock, Florida Shamrock, Georgia Shamrock, Illinois Shamrock, Louisiana Shamrock, Missouri
it is actually a three leaf clover and it is Are Lingus
Ryanair (small Irish airline)
The Delta Air Lines logo (commonly referred to as the Widget) is the fourth greek letter in the Greek alphabet for the word Delta.