Exhibit 21 DYNCORP AND SUBSIDIARIES Aerotherm Corporation Anedyn, Inc. Anedyn Power Company AT/Mexico Holdings Inc. Dyn Funding Corporation Dyn Logistics Services Inc. Dyn Marine Services, Inc. Dyn Marine Services of Virginia, Inc. Dyn/Mexico Holdings Inc. Dyn Network Management, Inc. Dyn Pacific Aerospace Services, Inc. Dyn Realty Corporation Dyn Systems Technology, Inc. Dyn Trade Systems, Inc. DynAir Technical Services, Inc. Dynalectron Corporation Dynalectron Systems Inc. DynCIS, Inc. DynComm 2000 LLC DynCorp DynCorp Advanced Repair Technology, Inc. DynCorp Aerospace Operations Inc. DynCorp Aerospace Operations (UK) Ltd. DynCorp Aviation Services, Inc. DynCorp Biotechnology and Health Services, Inc. DynCorp Information & Enterprise Technology, Inc. DynCorp Information Systems LLC DynCorp International Services, GmbH DynCorp International Services, Inc. DynCorp International Services, Ltd. DynCorp of Colorado, Inc. DynCorp Panama, Inc. DynCorp Procurement Systems, Inc. DynCorp Property Management, Inc. DynCorpServices.com, Inc. DynCorp Technical Services, Inc. DynCorp Tri-Cities Services, Inc. DynCorp Viar Inc. DynCorp West Virginia Inc. DynEDRS, Inc. DynEx, Inc. DynMeridian Corporation DynPar LLC DynSpace Corporation DynTel Corporation Electric Utility Construction, Inc. FMAS Corporation Grupo DynCorp de Mexico S.A. de C.V. Kwajalein Services, Inc. OLDHD Systems, Inc. Pacific TSD Corporation Sea Mobility Inc. TAI Realty Corporation