On May 20, 1958 a Vickers Viscount airliner operating Capital Airlines Flight 300 was involved in a mid-air collision with a United States Air Force T-33 jet trainer on a proficiency flight in the skies above Brunswick, Maryland. All 11 people on board the Viscount and one of the two crew in the T-33 were killed in the accident. Flight 300 was the second of four fatal crashes in the space of two years involving Capital Airlines Vickers Viscounts; the other were Capital Airlines Flight 67 (April 1958) Capital Airlines Flight 75 (May 1959) and Capital Airlines Flight 20 (January 1960).