It was announced last night that James Heilbrun '46, of the V-12 unit, will replace Frederic de Hoffmann '45, as chairman of the Harvard Council on Post-War Problems. De Hoffmann is leaving this week to enter government work.

Aviation problems in the post-war world will be discussed at a forum presented by the Post-War Council on Thursday, January 20, at 8 o'clock, in Pierce Hall, Harvard Engineering Building, on Oxford Street.

R. Dixon Speas, Assistant Vice-President of the American Airlines, who has just returned from a special assignment with the Army, will speak. John R. Markham, M. I. T. professor of Aeronautical Engineering and Massachusetts State Commissioner of Airports, will replace Otto C. Koppen, originally scheduled as the other speakers. They will discuss international and domestic aspects of post-war aviation, the political and economic importance of aviation, the problems of reconversion of aircraft industries.