Development of a new day bombardment technique, employing latest scientific devices to enable bombing through solid cloud cover -- "10/10ths" cloud, airmen call it -- was announced yesterday by Eighth Air Force Bomber Command headquarters.
    Announcement of the new technique had been withheld until its value had been tested in actual operation. Many of Eighth Air Force missions during the last three months against targets in Germany have been conducted over a solid cloud cover which blanketed most of Europe.

    While accuracy is not equal to that usually attained in high altitude attacks when the target can be seen, Eighth Air Force Bomber Command officials stated accuracy is satisfactory and gives promise of improvement. It was explained that the new technique is regarded as a logical outgrowth of American bombardment doctrine made possible by scientific advances and does not involve any basic change in the American conception of bombardment.
    Additional details of the technique are withheld for security reasons.
    The new method has been used on missions involving more than 8,000 bombers and fighters. Included were the successful attacks upon U-boat and shipbuilding facilities at Wilhelmshaven and at Kiel on Dec. 13. In both attacks the entire target areas were blanketed by solid cloud. At Wilhelmshaven, for instance, the aiming point for the bombers was the Bauhafen area.

    Results of the attack were not known until several days later when visibility permitted photographic reconnaissance. Pictures disclosed the aiming point well hit, with considerable damage to installations in the Bauhafen area.
    In the Marine-Werft, a number of buildings, chiefly on the south and west side of the Bauhafen, were damaged, including the lathe shop and joiners' shop, which was gutted, and a machine shop, which was severely damaged.
    A concentration of bombs fell in an area under reclamation to the north of the peninsula, and some damage was done to buildings of the Pulverhof ammunition depot. Several direct hits were scored on railways, breakwater and constructional installations in that region.
    Another concentration of bombs was seen to have fallen on the eastern edge of the new inner harbor with damage to dockside buildings.
    At Kiel, when visibility over the target area permitted photo reconnaissance, the photographs showed severe damage to the important shipbuilding yards of the Deutsche Werke, a top-priority target.
    Among the many buildings destroyed or damaged were the boat-building shops, plate shed, carpenter shop, iron stores, turbine engine workshop, engineering workshop, factory workshop, and slipways.
    Bremen and Emden were also targets of the overcast bombing technique.