Conversation so far:
how many seats are on a boeing 737-800
The Boeing 737-800 seats 162 passengers in a two-class layout or 189 passengers in a one-class layout.
When was the Boeing 737-800 first lounched
The 737-800 Boeing was launched on September 5, 1994.
When was the original Boeing line of airplanes first made
The first Boeing airplane also known as B & W seaplane was completed in June 1916 at Boeing's boathouse hangar on Lake Union in Seattle, Washington.

Question: When did the plane first fly
Self-contained rewrite: When did the Boeing plane first fly