Transcribed from The Miami News, Miami, Florida, March 2, 1960, page 12C:

Crash Clues Sifted, Then: ‘Blast Came From Within’

By Vern Haugland
AP Aviation Writer

How could they tell what caused it?

The men assigned to investigate the plane tragedy that took 34 lives early last Jan. 6 found wreckage scattered across marshlands near Bolivia, N.C.

There were several large pieces of the plane, including most of the cockpit. And there were more than 2,000 bits of debris. Some of the wreckage was missing. Bodies of two of the victims could not be found.

In the days that followed, there was speculation from Capital Hill that a suicide bomb had blown the plane apart in flight. Linked with this speculation was the name of Julian Andrew Frank, 32, a heavily insured New York attorney. But no evidence was disclosed showing Frank either wittingly or unwittingly carried a bomb aboard the DC-6B.

Then on Feb. 23 the chairman of the Civil Aeronautics Board, James R. Durfee, made an unprecedented progress report to the Senate Aviation subcommittee. Durfee told the senators, in part:

“… the board’s Bureau of Safety, with the assistance of the FBI and the many other laboratories that assisted us in our evaluations, is now prepared to say that we have found evidence that a dynamite explosion, initiated electrically by a dry cell battery, occurred within the aircraft cabin in the vicinity of the seat occupied by Julian Frank.”

The investigation still is going on. But here, in general, is how the investigators operated:

The experts held their first meeting within hours after they arrived at the scene. It was apparent to them that the National Airlines plane bound nonstop from New York to Miami had come apart in the air.

They considered these four possibilities:

  • An airborne collision.
  • Explosive decompression — or a “blowout” of the plane because of structural fatigue of its walls.
  • Explosive decompression because of puncturing by a propellar blade.
  • An explosive force from within.

Teams were set up to broaden the search. Marine helicopters joined the hunt. Twenty miles from the wreckage they made their find — Some 40 pieces of metal from the plane’s right forward side. It was scattered along Kure Beach — the point at which the Miami-bound airliners begin the over-ocean part of the flight.

Apparently it was over this beach that tragedy hit the plane.

A structure team also was organized. It included CAB engineers and representatives of the airline and the plane’s manufacturer.

A human factors team probed the mystery. A specialist from the Armed Forces Institute of Pathology conducted autopsies on five crew members, but reported no significant findings.

A witness group also was set up. There were no eyewitnesses, but 152 persons were questioned in five days.

An operations group checked the history of the plane and the flight. They found that no other aircraft had been in the area at the time. No missiles had been fired.

POSSIBILITY NO. 1 — A collision — could be crossed off.

The investigators set up a full-size wooden model of a DC-6B in a hangar at the Wilmington, N.C., airport. The model was covered with chicken wire. The experts began hanging bits of metal on it.

The wreckage at Kure Beach turned out to include a three-seat unit and large sections of the exterior wall. The sections fit neatly into an eight-foot hole up forward, on the right side, which remained after assemblage of the pieces found near Bolivia.

POSSIBILITY NO. 2 — Metal fatigue — was rules out. The experts said the DC-6B had been provided with a cross-webbed fuselage that would make a hole of such large size extremely unlikely.

Wings and the forward part of the plane had buried themselves deep in the marshland mud. Excavation of the engines was completed on the morning of Jan. 9. None of the propellar blades was missing.

POSSIBILITY NO. 3 — Puncturing by a propellar blade — had been ruled out.

A body was found embedded in mud near Kure Beach. The victim was identified as Frank. Parts of both legs were missing. The limb ends were strangely shredded.

One official said “it was the type of injury that could be caused by an explosion, such as that of a soldier who had stepped on a land mine.”

Later that same day, the CAB teams learned that Frank was under investigation for alleged fraud and that he had more than one million dollars worth of insurance — most of it taken out in the previous year.

At one time 60 different laboratory examinations were under way simultaneously — mostly tests of tissues from Frank’s body and metallurgical studies on the plane’s frame.

It was determined that Frank carried a blue cloth flight bag weighing 20 pounds when he boarded the plane. Such a bag — or what was left of it — was found near his body. Bits of blue fabric, steel wire, brass, wood, pain and other matter were found embedded in his body.

The search for more debris went on after the body of the last victim was found Jan. 14 about 1,000 yards from the main impact area near Bolivia.

The experts frankly were looking for explosives, and their failure to find such materials puzzled them.

But at last, tests of the rug fabrics, seat fabrics and general cabin debris began to turn up traces of nitrate — a basic component of dynamite. Also found were small black deposits of manganese dioxide, which is common to dry cell batteries.

Deep probes of Frank’s body turned up the same materials.

Nitrate and manganese dioxide both are highly soluble in water. Heavy rains had lashed the area. The investigators concluded that the wreckage and the body had been washed clean of all surface deposits of the tell-tale materials.

POSSIBILITY NO. 4 — An explosive force from within — was the one to which the evidence pointed.

Then seven weeks after the crash, Durfee made his report that, “We have found evidence that a dynamite explosion — occurred within the aircraft.”

The CAB will hold a public hearing March 22 at Wilmington.

Many questions remain unanswered. Who? Why? Was it a suicide bomb? A murder bomb?

But some of the biggest questions have been answered in what one CAB official calls “one of the most extensive investigations of its kind in 18 years of CAB operations.”