advance ratio


noun aeronautics

the ratio of wind speed along the axis of a rotor or propeller to the speed of the blade tip
the ratio of forward flight speed to the speed of the rotor tip of a helicopter

QUIZZES

IS YOUR DESERT PLANT KNOWLEDGE SUCCULENT OR DRIED UP?

Cactus aficionados, don't get left in the dust with this quiz on desert plants. Find out if you have the knowledge to survive this prickly foray into the desert!
Question 1 of 7
This tall, horizontally branched cactus is probably the most recognizable cactus in Arizona. What is it called?
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012