Narrative Description of situation: Aircrews are assigned to certain flights. For example crew #007 flies
the Washington D.C. to Miami route. Aircraft are flown by airlines, where a flight occurs on an aircraft with a
specific aircraft tail number. For example on Tuesday, 19 Feb, Boeing 767, tail number 0098 made the flight from Washington D.C. to Miami, designated United Flight 003. Pilots are a special category of crewmember who are qualified to fly specific types of aircraft. For example, Capt. Jones is qualified to fly the Boeing 767 and 757.

Build an entity relationship model for the above scenario.