One of the victims was retired U.S. Navy Vice Admiral Edward Orrick McDonnell, a Medal of Honor recipient and veteran of both World Wars.

[1] The windshield replacement procedure would take eight hours to perform, so National Airlines transferred the passengers of Flight 601 to two propliner aircraft it had in reserve.

[1] The crew consisted of stewardesses Mary O'Dell (24) and Valery Stewart (25), pilot Dale Southard (45), copilot Richard L. Hentzel (31), and flight engineer Robert R. Halleckson (34).

[6] He called Wilmington Airport to report the downed plane at approximately 7:00 a.m.[4] When Highway Patrol officers responded, he led them to the crash site.

[15] A fragment of aluminum, believed to be a piece of the airplane's skin, was found on Kure Beach, 25 miles (40 km) from the rest of the wreckage.

Investigators did not recover material from an irregular, triangularly shaped area positioned above the leading edge and extending forward ahead of the wing.

[17] The bodies were taken to the local high school gymnasium to await autopsy and identification by a Federal Bureau of Investigation (FBI) fingerprinting team.

[13] One of the victims was Vice Admiral Edward Orrick McDonnell, U.S. Navy (retired), a recipient of the Medal of Honor and a veteran of both World Wars.

[1] Other victims included a vice president of the Continental Bank of Cuba, a pharmacist, a student at the University of Miami, and an insurance adjuster.

[19] The autopsy revealed that his lower extremities had been ripped off; his muscle tissue was extensively mutilated and torn; small pieces of wire, brass, and miscellaneous articles including a hat ornament were embedded in various limbs; the fingers of his right hand were fractured and the bones splintered; and the distal phalanx of each finger on his left hand was missing.

The cause of the explosion was believed to be a bomb in the luggage of one of the passengers, Robert Vernon Spears, who enlisted a substitute to board the plane in his place.

Similarly, Julian Frank was covered by almost $900,000 (roughly equivalent to $7.1 million in 2023 dollars) in life insurance policies,[24][25] including some purchased the day of the crash.

[23] A life jacket from Kure Beach, found with parts of a flight bag embedded in it, tested positive for nitrate residue.

[21] In addition to the evidence collected from Frank's body, there were also samples of residue taken from the air vents and hat rack located on the right side of the aircraft near the leading edge of the wing.

[27] The Civil Aeronautics Board concluded the severity of Frank's injuries and the numerous particulates found embedded in his body could only be attributed to his proximity to an explosion.

The manganese dioxide samples collected from the seats near the focal point and from Frank's body indicated a dry cell battery was located very near the explosive.

[25] One of the first theories considered by investigators was that Flight 2511 was involved in a collision with another airliner, given the crash site's proximity to Wilmington Airport.

Alternatively, Julian Frank, who was known to be desperately afraid of flying, may have panicked and hit the window, weakening it in such a manner it subsequently blew out.

[29] This theory was supported by the wide right turn the aircraft appeared to make prior to disintegrating and crashing,[29] as well as the fact some of the passengers were found wearing life jackets.

In the telegram, they made a claim that the routine proficiency flights performed by pilots caused unnecessary stress on the aircraft.