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(a) Can be ejected from the seat onto which they are screwed, followmg fracture of their lower portion, by pressures ranging between 110 and 136 p.s.i. or thereabouts, namely, a pressure much higher than that which will, in fact, cause the tank structure to collapse and the fuel intake pipe (P.N. E78301) to crack;

(b) Cannot oe damaged, by stresses deriving from pressures of various strength, in such a wayr as to cause a breaking down of the various component parts resulting in the separation of the upper plate only [and no other damage}.

On the heels of these tests, it was definitely agreed that

the cap to which the plate belonged could not have been ejected from its seat (in the upper surface of the Wing) as a result

of explosnre forces (see pOint b).

Tests on the vent? outlets for the escape of gasoline vapors from the fuel tanks of the Super Constellation plane type 1619-11

These tests were made in order to ascertain whether the gasoline vapors, assumed to be flama‘ole, emerging from the vents, can be ignited electrically, and if so, whether the resulting fire, through the outlets, will spread to the interior of the tanks.

Under the conditions in which the tests were made, it was established that the gasoline vapors will ignite under certain conditions, but the flames W111 not Spread to the tanks.

Inspection of the inner surfaces of some pieces of pipes of the vent outlets for the escape of gasoline vapors, Helongmg to

wrecked plane Re. 7515; C.

The inspection was made in order to ascertain whether the condition of the surfaces gave physical evidence of the spreading of flames through these pipes.

The result of the inspection was negative.

Study of the p0531blli‘b3” of sabotage

This study was undertaken in order to ascertain whether it is possﬂole to introduce, through the fueling ports and into the fuel tanks, suitable compounds, properly prepared, which will later ignite the gasoline vapors existing in the tanks and cause them to explode, 1without leaVing any physmal eVidence.

It was concluded that such a pDSSibility existed and some examples are mentioned [later in the report].