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concurrence Wlth the existence of two vent outlets in tank No. 7, may have made it possible for the flames to spread to the interior of tank No. 7, causmg it to explode.

Similarly, in said tests no consideration was given to the possibility, howeVer improbable it might be, of the loss in flight of cap P.N. 750343843 (see par. 1h.LL.2.3, hypotheSis c), supposedly belonging to tank No. 7 (see par. 11, pOint 1), cap located on the upper surface of the Wing. This circumstance, whether or not in concurrence With other factors (see preceding par.),ma;y' in fact, have caused the fire to Spread to tank No. 7.

Lastly, the fact that the inspection of the inner surfaces of some sections of the outlet pipes taken from the wrecked plane showed no traces of the passage of flame (see par. 11.143), does not appear to be sufficient proof that such a circumstance did not actually take place. In fact, if flames had actually passad through the outlet pipes, their speed would have been too great to leave any traces on the inner walls of the pipes.

The likelihood of the hypothesis contemplated in this par. 11.h.2.6 requires the assumption that in the past, in spite

of the continuous operation of the Super Constellation 16149-11 planes, none of the aircraft of this type was ever involved

in that set of circumstances and conditions which, having occurred in the case of plane N. 7313-0, caused its destruction.

Such an assumption, although only a pos51bility, must be regarded as a matter for conSideration. In fact, no Super Constellation planes of the 16,494 model were, at least up to some time after the crash of the plane N.7313-C (see annex XIV-l), equipped With an anti-flame screen at the vent outlets and, at least on short or medium—length flights, they flew With tanks 5—6-7 empty.

Therefore, also because of the considerations mentioned above, the hypothesis in question, although based on some factual elements, can be proved orﬂy by a suitable series of tests on the ground and In flight.

This much havmg been said, it can be pOinted out that the

said hypothesis appears to be, indirectly, in agreement with almost all the statements made by the witnesses, regardless of the relative value at which such statements are taken; in

fact, in these statements the crash of the plane is closely associated with a lightning strike, with the follow1ng succession of events: