Page:CAB Accident Report, TWA Flight 891.pdf/37

 _37- Other installations

The remzximng installations, of lesser importance, were crammed and tested in a general way, but nothing abnormal was found.

11.2.3.6. Damage fromiightning

The wreckage was closely examined for eVidence of damage from lightning; when necessary, the examination was done with the aid of a magnifying glass.

No traces or Signs of structural damage of any significance due to lightning were found; in particular, the structures of tanks Nos. 6 and 7 showed no traces or Signs of damage of this kind (see par. 11.2.3.1).

However, Signs of lightning Strikes were found on many

parts of the plane, but they were no greater than those normally found on all planes; it was not possible to ascertain whether they had been produced during the plane‘s last flight or in previous flights.

Specifically, the following facts were ascertained:

[l] The lightning arrester ere of the RADAR cone on the plane's nose was burned and broken into two parts at a point 77 inches away, measured around its circumference, from the rear end of the cone's axis;

[2] Melted points, measuring 1 x 1/16 and l x 1/8 inches, were found, respectively, on the trailing edge of the left and right wing tips;

[3} Fifty—one caVities, or melted paints, in all, warying in diameter from 1/16 to 3/16 of an inch, and one hole 3/11 of an inch in 5126, were found on the upper outer surface of the left aileron;

[LL] Five small caVities, the largest of which was 1/1; of an inch in Size, were found on the right aileron;

[5] A hole 3/11 of an inch in Size and another 1 1/1; x 3/16 inches in size Were found on the lower trailing edge of the right rudder;

{6] A small melted paint about 1/1; of an inch in diameter was found on the lower trailing edge of the left rudder.

No Signs of lightning strikes were found on the static dischargers or the areas near them. Likewise, no endence of lightning strikes was found on the collectors of the fuel tank vent cutlets.