Day 244/22. Wokka Wokka

The Boeing CH-47 Chinook is a tandem rotor helicopter developed in the 1960's. Advanced versions are now serving in the Royal Air Force.
This is an RAF  Chinook during its flying display at the Bournemouth Airshow today. They are pretty common in the air around here ferrying cargo and personnel into the military ports in the region.
Why Wokka Wokka? Because that's the very distinctive noise that the rotors of a Chinook make. You cannot mistake it for anything else.
The Chinook is a heavy-lift helicopter that is among the heaviest lifting Western helicopters. Its name, Chinook, is from the Native American Chinook people of Oregon and Washington state.