59-20-02 LOCKHEED: Applies to All Model 1649A Aircraft.
Compliance required on items (1) and (2) by October 15, 1959; compliance required on item (3) by December 1, 1959.
As a result of a recent accident involving a suspected explosion of a wing tank, the following shall be accomplished to prevent the possible recurrence of such an explosion:
(1) Remove the static wick on the inboard wings adjacent to the tank vents.
(2) Install temporary placard at engineer's station reading as follows: "In order to maintain a nonexplosive rich mixture in tanks, do not use fuel out of auxiliary tanks Nos. 5, 6, and 7 below 50 gallons. In operations which involve use of fuel from main tanks only, the 50 gallons of residual fuel in the auxiliary tanks must be replaced with 50 gallons of fresh fuel or mixed with at least 150 gallons of fresh fuel at the end of every 12 flight-hours or 5 flights, whichever occurs first."
(3) Install P/N 634014-1 or equivalent flame arrestors in the tank vent outlets.
After installation of flame arrestors described in item (3), item (2) may be disregarded.