1959 MIDWAY AIRPORT, CHICAGO. When the TWA flight from Chicago to Los Angeles took off from Midway Airport, a fire developed in one engine and in attempting to circle back, the plane hit the ground and fire ensued. All the crew members and passengers were killed. Of 4,100 lbs. of mail aboard, about 85% was recovered and sent on to addressees without any endorsement, as was the case with this cover.