[robryk]

Both lift and drag are aerodynamic forces, so your approximation causes one to conclude that one need to simply spin everything faster. (And then we run into problems with transonic blades.)

> It's roughly equivalent to flying at 40,000 ft on Earth with an electric helicopter. The world record for highest helicopter ever flown is 42,500 ft on Earth.

The record was established in a jet-engined helicopter, whose service ceiling is largely a function of engine power at appropriate altitudes (e.g. it varies a lot with temperature and humidity).