It is important not to confuse IMC with IFR (instrument flight rules) â IMC describes the actual weather conditions, while IFR describes the rules under which the aircraft is flying. Aircraft can (and often do) fly IFR in clear weather, for operational reasons or when flying in airspace where flight under VFR is not permitted; indeed by far the majority of commercial flights are operated solely under IFR.
Norbert Rillieux. Norbert Rillieux (1806-1894) was the inventor of the multiple-effect vacuum evaporator, which revolutionized the processing of sugar. He gained recognition as one of the prime architects of the modern sugar industry.
Mae Jemison (born October 17, 1956) American physician and NASA astronaut known for being the first black woman to travel in space. Marie Maynard Daly (April 16, 1921 â October 28, 2003) The first African American woman to earn a Ph.D. in Chemistry. American inventor and engineer, best remembered for his invention of the multiple-effect evaporator. American ophthalmologist and inventor known for being the first African American woman doctor to receive a patent for a medical invention.