Vy & Vmc questions
1)*Why does Vy decrease with altitude?
Since a lighter plane produces a smaller horizontal component of lift when banked several degrees into the good engine, requiring more rudder travel to correct for sideslip—resulting in a higher Vmc than in a more heavily loaded plane, thus Vmc is tested on lightly loaded planes.
FAR, Sec. 23.149 says that “VMC must be determined with the most unfavorable weight.”*
2)*How, practically, does the FAA determine and load the “most unfavorable weight” for airplane it tests for Vmc? Do they use midget pilots, remote controls, partial fuel, or ghosts?
3)*Is there a quantifiable definition the FAA uses for "most unfavorable weight" among all planes it tests? All the other “specific circumstances” the FAA uses to test Vmc are specific; weight seems to be an ambiguous anomaly.