World's first jet aircraft took flight on this day in 1939, just days before World War II began - India Today
1st jet aircraft takes flight, August 27, 1939 - EDN
Heinkel He 178 The First Jet Power Aircraft
Aerospaceweb.org | Ask Us - Jet Engine Development
How superior were the early first generation jet fighters to late piston engine fighters? All these propeller-driven fighters had late war, or post war versions and have served deep into 50s, some
Frank Whittle tested first ever jet engine 80 years ago | Daily Mail Online