Technologia Aeroespacial Mexicana (TAM) has designed a strap-on helicopter. Tiny rockets on the tips of the propellers eliminate the need for a tail rotor, making it possible for the device to be worn on a human body. Credit: TAM. Ever since the first human saw a bird soaring through the clouds, our species has harbored a great envy for the freedom that flying gives. Now a company from Mexico is trying to capitalize on this desire with their design for a strap-on helicopter, which is intended to be worn on the back of an individual and lift them into...