WASHINGTON, Aug. 30 (AP) - The development of a paint that so reduced the visibility of an airplane that it was able to run a gauntlet of searchlights without being detected was reported by Army AirCorps officers today.

  Commenting on reports from Berlin that the British were using a sooty coating to black out their bombers, the officers disclosed that the United States Army had been experimenting for years with various so-called "invisible" paints.

  In contrast to the reported British method, the Army has been using a special buff paint that absorbs light so that when subjected to the glare of a searchlight it reflects few rays that can be seen by observers.

  For daytime use a two-tone coating is employed, with light blue hues on the under side of the plane to blend in with the sky and darker colors on the top side to blend with the ground. By that method the plane's visibility is reduced to observers both above and below.

  Experiments with "invisible" paints have been conducted for some time at Maxwell Field, Ala.