EXHIBIT 21 SUBSIDIARIES OF UNITED INDUSTRIAL CORPORATION MARCH 1, 1994 Approximate State Percentage of (or Jurisdiction) Voting Securities in which Owned by Name Incorporated Immediate Parent ------------------------------------------------------------------------------------ AAI Corporation Maryland 100% (a) A.A.I. Engineering Support, Inc. Maryland 100 (b) A.A.I. International, Inc. Delaware 100 (b) Seti, Inc. Pennsylvania 100 (b) AAI Systems Management, Inc. Maryland 100 (b) AAI Medical, Inc. Maryland 100 (b) AAI MICROFLITE Simulation Maryland 100 (b) International Corporation AAI/ACL Technologies, Inc. Maryland 100 (b) AAI California Carshells, Inc. Maryland 100 (b) Electric Transit, Inc. Ohio 53 (b) Detroit Stoker Company Michigan 100 (a) Midwest Metallurgical Laboratory, Inc. Michigan 100 (c) Neo Products Co. Illinois 100 (a) Symtron Systems, Inc. New Jersey 100 (a) U.I.C. -Del. Corporation Delaware 100 (a) <FN> (a)--Percentage owned by United Industrial Corporation ("United"). (b)--Percentage owned by AAI Corporation. (c)--Percentage owned by Detroit Stoker Company. All of the subsidiaries listed above are included in the consolidated financial statements of United. NYFS11...:\95\78495\0001\1196\EXH3295V.420